Draft Decision Guidance Document
Mercury
Rotterdam Convention
Operation of the prior informed consent procedure
for banned or severely restricted chemicals
Secretariat of the Rotterdam Convention
on the Prior Informed Consent Procedure for
Certain Hazardous Chemicals and Pesticides in International Trade
Table of Contents
Table of Contents 2
Introduction 3
Standard core set of abbreviations 5
1. Identification and uses (see Annex 1 for further details) 7
2. Reasons for inclusion in the PIC procedure 8
2.1 Final regulatory action (see Annex 2 for further details) 8
2.2 Risk evaluation (see Annex 1 for further details) 8
3. Protective measures that have been applied concerning the chemical 10
3.1 Regulatory measures to reduce exposure 10
3.2 Other measures to reduce exposure 11
3.3 Alternatives 11
3.4 Socio-economic effects 11
4. Hazards and risks to human health and the environment 12
4.1 Hazard Classification 12
4.2 Exposure limits 12
4.3 Packaging and labelling 13
4.4 First aid 13
4.5 Waste management 14
Annex 1: Further information on the substance 15
1. Physico-chemical properties 15
2. Toxicological properties 15
3. Human exposure/risk evaluation 20
4. Environmental fate and effects 22
5. Environmental exposure/risk evaluation 23
Annex 2: Details on final regulatory actions reported 25
Annex 3: Addresses of designated national authorities 31
Annex 4: References 32
1. Regulatory actions 32
2. Supporting Documentation 32
3. Other Documents 32
Introduction
The objective of the Rotterdam Convention is to promote shared responsibility and cooperative efforts among Parties in the international trade of certain hazardous chemicals in order to protect human health and the environment from potential harm and to contribute to their environmentally sound use, by facilitating information exchange about their characteristics, by providing for a national decision-making process on their import and export and by disseminating these decisions to Parties. The Secretariat of the Convention is provided jointly by the United Nations Environment Programme (UNEP) and the Food and Agriculture Organization of the United Nations (FAO).
Candidate chemicals1 for inclusion in the prior informed consent (PIC) procedure under the Rotterdam Convention include those that have been banned or severely restricted by national regulatory actions in two or more Parties2 in two different regions. Inclusion of a chemical in the PIC procedure is based on regulatory actions taken by Parties that have addressed the risks associated with the chemical by banning or severely restricting it. Other ways might be available to control or reduce such risks. Inclusion does not, however, imply that all Parties to the Convention have banned or severely restricted the chemical. For each chemical included in Annex III of the Rotterdam Convention and subject to the PIC procedure, Parties are requested to make an informed decision whether they consent or not to the future import of the chemical.
At its […] meeting, held in […] on […], the Conference of the Parties agreed to list [chemical name] in Annex III of the Convention and adopted the decision-guidance document with the effect that this group of chemicals became subject to the PIC procedure.
The present decision-guidance document was communicated to designated national authorities on […], in accordance with Articles 7 and 10 of the Rotterdam Convention.
Purpose of the decision guidance document
For each chemical included in Annex III of the Rotterdam Convention, a decision-guidance document has been approved by the Conference of the Parties. Decision-guidance documents are sent to all Parties with a request that they make a decision regarding future import of the chemical.
Decision-guidance documents are prepared by the Chemical Review Committee. The Committee is a group of government-designated experts established in line with Article 18 of the Convention, which evaluates candidate chemicals for possible inclusion in Annex III of the Convention. Decision-guidance documents reflect the information provided by two or more Parties in support of their national regulatory actions to ban or severely restrict the chemical. They are not intended as the only source of information on a chemical nor are they updated or revised following their adoption by the Conference of the Parties.
There may be additional Parties that have taken regulatory actions to ban or severely restrict the chemical and others that have not banned or severely restricted it. Risk evaluations or information on alternative risk mitigation measures submitted by such Parties may be found on the Rotterdam Convention website (www.pic.int).
Under Article 14 of the Convention, Parties can exchange scientific, technical, economic and legal information concerning the chemicals under the scope of the Convention including toxicological, ecotoxicological and safety information. This information may be provided directly to other Parties or through the Secretariat. Information provided to the Secretariat will be posted on the Rotterdam Convention website.
Information on the chemical may also be available from other sources.
Disclaimer
The use of trade names in the present document is primarily intended to facilitate the correct identification of the chemical. It is not intended to imply any approval or disapproval of any particular company. As it is not possible to include all trade names presently in use, only a number of commonly used and published trade names have been included in the document.
While the information provided is believed to be accurate according to data available at the time of preparation of the present decision-guidance document, FAO and UNEP disclaim any responsibility for omissions or any consequences that may arise there from. Neither FAO nor UNEP shall be liable for any injury, loss, damage or prejudice of any kind that may be suffered as a result of importing or prohibiting the import of this chemical.
The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of FAO or UNEP concerning the legal status of any country, territory, city or area or of its authorities or concerning the delimitation of its frontiers or boundaries.
Standard core set of abbreviations
<
Less than
<
Less than or equal to
>
Greater than
>
Greater than or equal to
µg
Microgram
m
Micrometre
ARfD
Acute reference dose
a.i.
Active ingredient
ADI
Acceptable daily intake
AOEL
Acceptable operator exposure level
b.p.
Boiling point
bw
Body weight
oC
Degree Celsius (centigrade)
CAS
Chemical Abstracts Service
cc
Cubic centimetre
cm
Centimetre
DNA
Deoxyribose nucleic acid
DT50
Dissipation time 50%
EC50
Median effective concentration
ED50
Median effective dose
ECHA
EEC
European Chemicals Agency
European Economic Community
EHC
Environmental Health Criteria
EU
European Union
FAO
Food and Agriculture Organization of the United Nations
g
Gram
h
Hour
ha
Hectare
i.m.
Intramuscular
i.p.
Intraperitoneal
IARC
International Agency for Research on Cancer
IC50
Median inhibitory concentration
ILO
International Labour Organization
IPCS
International Programme on Chemical Safety
IPM
Integrated Pest Management
IUPAC
International Union of Pure and Applied Chemistry
JMPR
Joint FAO/WHO Meeting on Pesticide Residues (Joint Meeting of the FAO Panel of Experts on Pesticide Residues in Food and the Environment and a WHO Expert Group on Pesticide Residues)
kg
Kilogram
Koc
Soil organic partition coefficient.
Kow
Octanol–water partition coefficient
kPa
Kilopascal
L
Litre
LC50
Median lethal concentration
LD50
Median lethal dose
LOAEL
lowest-observed-adverse-effect level
LOEL
Lowest-observed-effect level
m
Metre
m.p.
Melting point
mg
Milligram
ml
Millilitre
mPa
Millipascal
MRL
Maximum residue limit
MTD
Maximum Tolerated Dose
ng
Nanogram
NOAEC
No-observed-adverse-effect concentration
NOAEL
No-observed-adverse-effect level
NOEC
No-observed-effect concentration
NOEL
No-observed-effect level
OECD
Organisation for Economic Co-operation and Development
PEC
Predicted environmental concentration
Pow
Octanol-water partition coefficient, also referred to as Kow
PPE
Personal protective equipment
ppm
Parts per million (used only with reference to the concentration of a pesticide in an experimental diet. In all other contexts the terms mg/kg or mg/L are used).
RfD
Reference dose (for chronic oral exposure; comparable to ADI)
SMR
Standard(ized) mortality ratio
STEL
Short-term exposure limit
TER
Toxicity exposure ratio
TLV
Threshold limit value
TWA
Time-weighted average
UNEP
United Nations Environment Programme
USEPA
United States Environmental Protection Agency
UV
Ultraviolet
VOC
Volatile organic compound
w/w
Weight for weight
WHO
World Health Organization
wt
Weight
Decision guidance document for a banned or severely restricted chemical
Mercury
Published:
1. Identification and uses (see Annex 1 for further details)
Common name
Mercury
Chemical name and other names or synonyms
Mercury
Molecular formula
Hg
Chemical structure
Hg
CAS No.
7439-97-6
Harmonized System Customs Code
2805.40
Other numbers
EC number 231-106-7
Category
Industrial
Regulated category
Industrial
Use(s) in regulated category
In Colombia, mercury was used in mining, chlor-alkali industry, production of fluorescent lamps and in the manufacture of dental amalgams. The final regulatory action prohibited the marketing and use of mercury in the different industrial activities on July 15, 2013, the use of mercury in mining activities from July 15, 2018, and all other industrial activities including the manufacture of dental amalgams from July 15, 2023.
In the European Union, mercury was used in mining, chlor-alkali industry, the production of lamps, electrical and electronic devices. The final regulatory action notified by the European Union severely restricts the industrial use of mercury in several sectors through different Directives and Regulations.
The Minamata Convention on Mercury aims to protect human health and the environment from anthropogenic emissions and releases of mercury and mercury compounds. The Convention addresses all aspects of the life cycle of mercury, including:
• the direct mining of mercury, its export and import, its safe storage and its disposal once it becomes waste,
• the reduction and where feasible the elimination of the use and release of mercury from artisanal and small-scale gold mining,
• the control of mercury air emissions from coal-fired power plants, coal-fired industrial boilers, certain non-ferrous metals production operations, waste incineration and cement production,
• the phase-out or reduction of mercury use in certain products such as batteries, switches, lights, cosmetics, pesticides and measuring devices, and creating initiatives to reduce the use of mercury in dental amalgam, and
• the phase out or reduction of the use of mercury in manufacturing processes such as chlor-alkali production, vinyl chloride monomer production, and acetaldehyde production
Trade names
Colloidal mercury, Quicksilver, Liquid silver, Hydrargyrum. This is an indicative list. It is not intended to be exhaustive.
Formulation types
Elemental Mercury
Uses in other categories
Use as a chemical intermediate in the manufacture of various industrial chemicals and processes (UNEP 2017).
Basic manufacturers
Avantor, Inc. (Thermo Fisher Scientific), AHSA, Aldrett Hermanos SA de CV., Merck KGaA. This is an indicative list of current and former manufacturers. It is not intended to be exhaustive.
2. Reasons for inclusion in the PIC procedure
Mercury is included in the PIC procedure as an industrial chemical. It has been listed on the basis of the final regulatory actions to severely restrict its use, notified by Colombia and the European Union. Contact details of the designated national authorities of these two Parties are set out in annex 3 to the decision guidance document.
2.1 Final regulatory action (see Annex 2 for further details)
Colombia
Based on Law 1658 of 15 July 2013, the government of Colombia prohibited the marketing and use of mercury. The regulation eradicates the use of mercury in the national territory in: 1) all industrial and production processes within a period not exceeding 10 years (until 15 July 2023), and 2) for mining within a maximum period of 5 years (until 15 July 2018). The deadline for industrial uses other than mining has not been met; this is the reason why the use of mercury in the production of dental amalgam will continued until 15 July 2023.
Reason: Human Health and Environment
European Union
The use of mercury as an industrial chemical is severely restricted in the European Union pursuant to Regulation (EU) 2017/852 on mercury, Regulation (EC) 1907/2006 (REACH), Directive 2011/65/EU (RoHS) and Directive 2006/66/EC (batteries and accumulators). More specifically:
(a) In 2006, Directive 2006/66/EC introduced a prohibition on the placing on the market of batteries and accumulators containing mercury;
(b) In 2007, Directive 2007/51/EC introduced a restriction under Directive 76/769/EEC on the placing on the market of mercury in fever thermometers and in other measuring devices intended for sale to the general public;
(c) Regulation (EC) No 1907/2006 (REACH) repealed Directive 76/769/EEC. Commission Regulation (EC) No 552/2009 amended Annex XVII to REACH by incorporating in entry 18.a the restrictions on certain measuring devices containing mercury that was adopted under Directive 2007/51/EC;
(d) In 2011, Directive 2011/65/EU (RoHS) established a restriction on the placing on the market of electric and electronic equipment to a maximum concentration value of 0.1% of mercury, allowing exemptions for certain applications for a limited time period;
(e) Commission Regulation (EU) No 847/2012 amended Annex XVII to REACH by incorporating in entry 18.a. a restriction on the placing on the market of mercury-containing and mercury- using measuring devices intended for industrial and professional uses. The restriction started to apply from 10 April 2014.
Regulation (EU) 2017/852 on mercury was adopted in May 2017. This regulation complements the European Union acquis and lays down the provisions that are needed to ensure the complete alignment of the European Union acquis with the Minamata Convention on Mercury establishing measures and conditions concerning the use and storage of and trade in mercury, mercury compounds and mixtures of mercury, and the manufacture and use of and trade in mercury-added products, and the management of mercury waste.
Reason: Human Health and Environment
2.2 Risk evaluation (see Annex 1 for further details)
Colombia
According to the evaluation related to human health and the environment, the following information was identified:
(a) The data includes extensive neuro-epidemiological studies in exposed populations (occupational and general population) and studies in different environmental compartments (freshwater, soil, sediment, biota, etc.), food (fish), with a view of establishing the levels of mercury and the perception of risk, and generating scientific, regulatory and technical evidence on the mercury problem both at the national and international level of the health sector and other related sectors. Mercury measurements have been made in humans, mainly in workers and communities surrounding mining activities or adjacent to riverine areas;
(b) The evaluation conducted establish that mercury is a toxic substance, that when entering the human body produces disorders, mainly at the central nervous system level. The presence of mercury in the air, water, soil and food (mainly fish) in concentrations above the allowed limit has caused a serious public health problem in Colombia. Regions such as the Northeast of Antioquia, the South of Bolívar, Chocó, Santander, Nariño, Caldas, Vaupés, among others, carry out artisanal gold mining and for the final extraction of this precious metal, mercury is used. Its use occurs in an indiscriminate and poorly controlled way, a situation that has caused environmental contamination and has affected people's health. Exposure to mercury is also increased in industrial areas that use this substance;
(c) Studies conducted by the Government of Antioquia in the municipalities of Segovia and Remedios, in the Northeast of the department, found a concentration of mercury of approximately 340 μg/m³ in the air (300 times higher than the guideline of the World Health Organization for public maximum exposure to vapour of mercury). Approximately 26 to 6,118 ppm of Hg is discharged into rivers by miners in the region. Additionally, the main food of these communities is fish, which has been shown to be affected by the emission of mercury. Studies completed by Corantioquia, the University of Antioquia, and the University of Cartagena have revealed a concentration above 1.06 μg Hg/g in most of the species found in the rivers of the surrounding area;
(d) Mercury contamination in Colombia was originated in the gold benefit processes in which the mineral containing the precious metal is extracted by joining with the mercury, forming the amalgam. During the process, mercury spills into water bodies and the environment. Subsequently, the amalgam obtained is burned in the open air, leaving the gold and releasing the toxic mercury vapours into the atmosphere. All these activities are performed very close to the miners' households, in such a way that families breathe a large part of the volatilized mercury vapour. Even remote populations can be affected by the mobilization of this substance (Protocol for Surveillance and Control of Acute Mercury Poisoning);
(e) Studies carried out in exposed populations (occupational and general population) to mercury have made it possible to establish its relationship in the development of the observed manifestations (Fawer et al 1983, Piikivi 1989, Marh et al 1987). The neuroepidemiological and toxicological study of the Suratá river pollutants carried out in the mining population of that region (Santander, 1992) raised the possible relationship of chronic exposure to mercury with the presence of neurological diseases. Tirado et al (2000) suggest that this form of exposure can cause neuropsychological and behavioural deficits in the population. In 1995, Olivero et al reported that the inhabitants of southern Bolívar presented signs of mercury intoxication such as hand tremors, neurological disorders and visual problems, among others. In this region, frequent cases of congenital malformations have also been reported, although without evidence of association with mercury exposure;
(f) According to National Public Health Surveillance System - SIVIGILA, during 2010 and in the first half of 2011, 201 cases of mercury poisoning were reported in Colombia- 96% of the cases were of occupational or accidental origin as follows: 85% (n = 171) occupational, 11% (n = 22) accidental;
(g) Occupational exposure is the most frequent in the reported cases, where mining and quarrying occupations are the ones with the highest number of cases associated with the use of mercury as an input for gold mining. The most significant conclusions indicate that the most frequent notifiers during the period were Antioquia, followed by Bogotá, Bolívar, Risaralda, Santander and Valle del Cauca. The highest percentage of intoxications reported were occupational, been respiratory the most frequent route of exposure, and according to the analysis by occupation, the highest number of intoxicated were miners or stonemasons (Scientific, Regulatory and Technical Evidence on the Mercury Problem at the Level National and International Health Sector and Other Related Sectors);
(h) It was identified that there are some population groups that deserve special attention in relation to exposure to mercury, since they have a greater probability of exposure to dangerous levels, or because carriers of disease, the intoxication effects can be exacerbated:
(i) Workers exposed to mercury;
(ii) General population next to sources of mercury contamination (mines, industries);
(iii) Populations in areas contaminated by mercury, especially indigenous and riverine, whose main source of proteins is fish;
(iv) People using mercury-containing medications for a long time;
(v) People with central nervous system diseases, patients with chronic kidney and bronco pulmonary failure;
(vi) Pregnant women and toddlers.
European Union
According to the evaluation related to human health and the environment, the following information was identified:
(a) While this risk assessment was conducted in the context of the restriction on mercury-containing measuring devices intended for industrial and professional uses, it includes information on the risks associated with mercury that is not limited to those measuring devices and that could support the other Directives and Regulations that comprise the final regulatory action notified by the European Union.
(b) According to the ECHA Committee for Risk Assessment (RAC) Opinion and its background document, mercury and its compounds are highly toxic to humans, ecosystems and wildlife, with amongst others serious chronic irreversible adverse neurotoxic and neurodevelopmental effects. The RAC opinion includes a PBT assessment for mercury-methylmercury concluding an equivalent level of concern in terms of persistency, due to mercury cycling and methylation versus demethylation rates under anaerobic conditions, as well as the clear potential for bioaccumulation and toxicity identified for methylmercury.
(c) The hazard and fate of mercury and its compounds are described in numerous peer-reviewed reports, which were referenced in the Documentation provided:
(i) ‘Global Mercury Assessment’, published by UNEP in 2002 (and UNEP 2008a and b);
(ii) ‘Methylmercury’ (WHO, 1990);
(iii) ‘Risks to Health and the Environment Related to the Use of Mercury Products’ prepared for the Commission by RPA in 2002.
(d) It is estimated that 3.5–7.6 tonnes of mercury are placed on the market in mercury containing measuring devices in 2010. These amounts are used to estimate the maximum potential for mercury emissions to the environment that might ultimately occur. This assumption is considered appropriate because of an estimated low separate collection rate of mercury waste and resulting inadequate waste treatment of a substantial part of the devices. This inappropriate waste collection leads in the long term to a relatively high share of mercury used in these devices being released to the environment. For measuring equipment using mercury (porosimeters, mercury probes used for capacitance-voltage determinations and mercury electrodes used in voltammeters) the total use is 5–15 tonnes per year (mostly porosimeters 5–14 tonnes per year). It should be noted that these figures are the amount of mercury the laboratories purchase and cannot be used to estimate maximum potential for emission as is the case for the measuring equipment containing mercury. To estimate emissions several additional factors need to be considered. These include number of measurements carried out, practices to purify and regenerated used mercury and the risk management measures and operational conditions applied to control the emissions and exposures.
(e) The total mercury consumption in Europe was in 2007 estimated to be 320–530 tonnes. 160–190 tonnes of the total amount were used in the chlor-alkali production and 90–110 were used in dental amalgams. The amount used in mercury measuring devices thus equals about 4% of the total, while the restricted devices will be lower due to the large use in porosimeters.
(f) Once released to the environment, mercury persists in the environment, where it circulates between air, water, sediments, soil and biota in various forms. Mercury can be transformed to methylmercury, the most toxic form, which biomagnifies especially in the aquatic food chain, making populations and wildlife with a high intake of fish and seafood particularly vulnerable.
(g) Several existing pieces of legislation in the European Union abate the risks arising from mercury in different stages of the life cycle of measuring devices. However, none of the measures currently in place is sufficient to remove the concern fully, although there is a difference between their observed effectiveness with regard to measuring devices containing mercury and measuring devices using mercury.
(h) The emissions from mercury measuring devices, although relatively small, contribute to the overall emissions of mercury to the environment and thereby also to the exposure of species and of humans via the environment. Therefore, measuring devices containing or using mercury are of concern.
3. Protective measures that have been applied concerning the chemical
3.1 Regulatory measures to reduce exposure
Colombia
The government of Colombia prohibited the marketing and use of mercury in the different industrial activities under Law 1658 on July 15, 2013, the use of mercury in mining activities from 15 July 2018, and all other industrial activities including the manufacture of dental amalgams from 15 July 2023.
European Union
The final regulatory action notified by the European Union severely restricts the industrial use of mercury in several sectors through different Directives and Regulations. More specifically:
(a) In 2006, Directive 2006/66/EC introduced a prohibition on the placing on the market of batteries and accumulators containing mercury;
(b) In 2007, Directive 2007/51/EC introduced a restriction under Directive 76/769/EEC on the placing on the market of mercury in fever thermometers and in other measuring devices intended for sale to the general public;
(c) Regulation (EC) No 1907/2006 (REACH) repealed Directive 76/769/EEC. Commission Regulation (EC) No 552/2009 amended Annex XVII to REACH by incorporating in entry 18.a the restrictions on certain measuring devices containing mercury that was adopted under Directive 2007/51/EC; In 2011, Directive 2011/65/EU (RoHS) established a restriction on the placing on the market of electric and electronic equipment to a maximum concentration value of 0.1% of mercury, allowing exemptions for certain applications for a limited time period;
(d) Commission Regulation (EU) No 847/2012 amended Annex XVII to REACH by incorporating in entry 18.a. a restriction on the placing on the market of mercury-containing and mercury- using measuring devices intended for industrial and professional uses. The restriction started to apply from 10 April 2014.
Regulation (EU) 2017/852 on mercury was adopted in May 2017. This regulation complements the European Union acquis and lays down the provisions that are needed to ensure the complete alignment of the European Union acquis with the Minamata Convention on Mercury establishing measures and conditions concerning the use and storage of and trade in mercury, mercury compounds and mixtures of mercury, and the manufacture and use of and trade in mercury-added products, and the management of mercury waste.
3.2 Other measures to reduce exposure
Colombia
None reported.
European Union
None reported.
3.3 Alternatives
Colombia
No information was provided.
European Union
No information was provided.
General
The Minamata Convention on Mercury addresses all aspects of the life cycle of mercury, including requiring controls and reductions across a range of products, processes and industries. Updated information on the phase out of products containing mercury and available alternatives to these products, including alternatives to the use of mercury in manufacturing processes and mining is available on the Convention’s website at https://minamataconvention.org
3.4 Socio-economic effects
Colombia
No assessment of socio-economic effects was reported.
European Union
No assessment of socio-economic effects was reported.
4. Hazards and risks to human health and the environment1
4.1 Hazard Classification
WHO / IPCS
Mercuric chloride, Class Ib
Mercuric oxide, Class Ib
Mercurous chloride, Class II
IARC
Group 3 (not classifiable as to their carcinogenicity to humans)
Methylmercury, Group 2B (possibly carcinogenic to humans)
European Union
Acute Tox 2 : H330 - fatal if inhaled.
STOT RE 1: H372 – causes damage to organs through prolonged or repeated exposure .
Aquatic Acute 1: H400 – very toxic to aquatic life.
Aquatic Chronic 1: H410 – very toxic to aquatic life with long lasting effects.
Repr. 1B: H360D – may damage the unborn child.
US EPA
Carcinogenicity classification:
Mercury, elemental D (IRIS 1995a)
Mercuric chloride C (IRIS 1995b)
Methylmercury C (IRIS2001)
1: Elemental mercury is ionized and methylized in the environment and therefore this chapter includes information on hazard, exposure and risk of mercury compounds.
4.2 Exposure limits
WHO (2021)
In 2003 the Joint FAO/WHO Expert Committee on Food Additives (JECFA) established a tolerable intake of 1.6 µg/kg body weight per week for dietary exposure to methylmercury in order to protect the developing foetus from neurotoxic effects. In 2006, JECFA clarified that life stages other than the embryo and foetus may be less sensitive to the adverse effects of methylmercury. For adults, up to about twice the tolerable intake per week would not pose any risk of neurotoxicity. However, available data did not allow firm conclusions to be drawn for children (aged up to about 17 years), as they may be more sensitive than adults. Hence the tolerable intake established in 2003 applies also to children.
In 2010 JECFA established a provisional tolerable weekly intake for inorganic mercury of 4 μg/kg body weight, applicable to dietary exposure to total mercury from foods other than fish and shellfish.
Drinking water: 6 µg/litre for inorganic mercury.
Air: 1 µg/m3 (annual average).
WHO estimated a tolerable concentration of 0.2 µg/m3 for long-term inhalation exposure to elemental mercury vapour, and a tolerable intake of total mercury of 2 µg/kg body weight per day (17).
SCOEL/SUM/84 (2007)
Occupational exposure:
8-hour Total Weight Average (TWA): 0.02 mg mercury/m3
Biological limit values (BLV): 10 µg Hg/l blood; 30 µg Hg/g creatinine in urine
4.3 Packaging and labelling
The United Nations Committee of Experts on the Transportation of Dangerous Goods classifies the chemical in:
Hazard Class and Packing Group:
UN Hazard Class: 8
UN subsidiary risk: 6.1
UN pack Group III
Source: ICSC 0056 - MERCURY (inchem.org)
UN shipping names
ADR/RID/IMDG: MERCURY
International Maritime Dangerous Goods (IMDG) Code
According to UN GHS Criteria
DANGER
May be corrosive to metals
Fatal if inhaled
May damage fertility or the unborn child
Causes damage to central nervous system and kidneys
Causes damage to the central nervous system and the kidneys through prolonged or repeated exposure
Very toxic to aquatic life with long lasting effects
Transport Emergency Card
ICSC 0056 - MERCURY (inchem.org)
4.4 First aid
NOTE: The following advice is based on information available from the World Health Organisation and the notifying countries and was correct at the time of publication. This advice is provided for information only and is not intended to supersede any national first aid protocols.
International Chemical Safety Cards (ICSCs): ICSC 0056 - MERCURY (inchem.org)
Description of first aid measures
AVOID ALL CONTACT! IN ALL CASES CONSULT A DOCTOR!
SYMPTOMS
PREVENTION
FIRST AID
Inhalation
Cough. Sore throat. Shortness of breath. Fever. Vomiting. Diarrhoea. Abdominal pain. Headache. Weakness.
Use local exhaust or breathing protection.
Fresh air, rest. Artificial respiration may be needed. Refer immediately for medical attention.
Skin
MAY BE ABSORBED! Redness.
Protective gloves. Protective clothing.
Remove contaminated clothes. See Notes. Rinse and then wash skin with water and soap. Refer for medical attention.
Eyes
Wear face shield or eye protection in combination with breathing protection.
First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.
Ingestion
Do not eat, drink, or smoke during work. Wash hands before eating.
Refer for medical attention.
Fire-fighting measures
In case of fire in the surroundings, use appropriate extinguishing media. In case of fire: keep drums, etc., cool by spraying with water.
Spillage disposal
Evacuate danger area! Consult an expert! Personal protection: chemical protection suit and filter respirator for mercury adapted to the airborne concentration of the substance. Ventilation. DO NOT let this chemical enter the environment. Collect leaking and spilled liquid in sealable non-metallic containers as far as possible. Then store and dispose of according to local regulations.
Storage
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. Well closed. Store in an area without drain or sewer access.
4.5 Waste management
Regulation (EU) 2017/852 on mercury was adopted in May 2017. This regulation complements the European Union acquis and lays down the provisions that are needed to ensure the complete alignment of the European Union acquis with the Minamata Convention on Mercury establishing measures and conditions concerning the use and storage of and trade in mercury, mercury compounds and mixtures of mercury, and the manufacture and use of and trade in mercury-added products, and the management of mercury waste.
Basel Technical guidelines on the environmentally sound management of wastes consisting of, containing or contaminated with mercury or mercury compounds are available - Adopted by COP-15, June 2022 (Technical guidelines).
Annexes
Annex 1:
Further information on the substance
Annex 2:
Details on final regulatory action
Annex 3:
Address of designated national authorities
Annex 4:
References
Annex 1: Further information on the substance
The information presented in this annex reflects the conclusions of the notifying Parties: Colombia and the European Union. The notification from Colombia was published in PIC Circular LII of December 2020. The notification from the European Union was published in PIC Circular LVI of December 2022.This information has been taken from the notifications of the final regulatory actions to ban mercury and the supporting documents.
The toxicity of mercury is very well documented internationally and only a brief summary of data to supplement information provided in the notifications is included in this annex. This annex is not meant to be a comprehensive review of the toxicological profile of mercury.
More detailed information is available in the following UNEP Mercury Assessments:
(a) Global Mercury Assessment 2002;
(b) The Global Atmospheric Mercury Atmospheric Assessment 2008: Sources, Emissions and Transport;
(c) Global Mercury Assessment 2013: Sources, emissions, releases, and environmental transport;
(d) Global Mercury Assessment 2018.
The global lifecycle of mercury is addressed under the Minamata Convention on Mercury.
1. Physico-chemical properties
1.1
Identity
Mercury
1.2
Formula
Hg
1.3
Molecular weight
200.6 g/mol
1.4
Colour and Texture
Silver-white liquid at room temperature
1.5
Melting point
Melting point: -39C (at 101 325 Pa)
1.6
Boiling point
Boiling point: 357C (at 101 325 Pa)
1.7
Density
13.5 g/cm3 at 25C
1.8
Solubility in water
none
1.9
Vapour density
(air=1) 6.93
1.10
Vapour pressure
0.26 Pa at 20C
1.11
Viscosity
1.55 mPa s at 20C
1.12
Relative density vapour/air-mixture
1.009 (ait=1) at 20C
2. Toxicological properties
2.1
General
European Union
Mercury is a chemical of global concern owing to its long-range atmospheric transport, its persistence in the environment once anthropogenically introduced, its ability to bioaccumulate in ecosystems and its significant negative effects on human health, which include significant adverse neurological and other health effects, with particular concerns expressed about its harmful effects on infants and unborn children.
Mercury can be transformed to methylmercury, the most toxic form, which biomagnifies especially in the aquatic food chain, making populations and wildlife with a high intake of fish and seafood.
2.1.1
Mode of Action
European Union
Elemental mercury is very toxic to humans via inhalation. About 80 percent of inhaled vapours are absorbed by the lung tissues. This vapour easily penetrates the blood-brain barrier and is a well documented neurotoxicant causing neurological and behavioural disorders in humans when inhaled. Specific symptoms include tremors, emotional lability, insomnia, memory loss, neuromuscular changes, and headaches. Intestinal absorption of elemental mercury is low.
WHO (2003)
At high levels of exposure, elemental mercury induces adverse effects in most organ systems in the body. Respiratory failure, cardiac arrest, and cerebral oedema are the causes of death in fatal cases.
The central nervous system is the most sensitive target for elemental mercury vapour exposure. Similar effects are seen following all durations of exposure, but their severity increases as exposure duration and/or concentration increase. Long-term exposure to elemental mercury may lead to changes in renal function.
2.1.2
Symptoms of poisoning
WHO (2003)
Prominent symptoms include tremors, emotional lability, insomnia, memory loss, neuromuscular changes, headaches, polyneuropathy, and performance deficits in tests of cognitive or motor function.
2.1.3
Absorption, distribution, excretion and metabolism in mammals
WHO (2003)
Inhalation is the primary route of entry into the body for elemental mercury, while oral exposure is the primary route for inorganic mercury salts. Dermal penetration is usually not a significant route of exposure to inorganic mercury.
Approximately 80% of inhaled elemental mercury is absorbed through the lungs by rapid diffusion. In contrast, only 0.01% of elemental mercury is absorbed through the gastrointestinal tract, possibly because of its enterogastric conversion to divalent mercury and subsequent binding to sulfhydryl groups. Dermal absorption of elemental mercury is limited. Dermal absorption is estimated to contribute approximately 2.6% of the absorbed mercury following exposure to elemental mercury vapour in the air; the other 97.4% occurs through inhalation.
The absorption, blood levels, and excretion of mercury evaluated in nine healthy volunteers (two males, seven females) exposed to mercury vapour in air at 400 µg/m3 for 15 min corresponded to a dose of 5.5 nmol mercury/kg body weight. Samples of exhaled air, blood, and urine were collected for 30 days after exposure. The median retention of elemental mercury after 30 days was 69% of the inhaled dose. This corresponds to the estimated half-life of approximately 60 days for elemental mercury.
The lipophilic nature of elemental mercury results in its distribution throughout the body. Elemental mercury dissolves in the blood upon inhalation, and some remains unchanged. Elemental mercury in the blood is oxidized to its divalent form in the red blood cells. The divalent cation exists as a diffusible or non-diffusible form. The non-diffusible form exists as mercuric ions that bind to protein and are held in high-molecular-weight complexes, existing in equilibrium with the diffusible form. In the plasma, the mercuric ion is predominantly non-diffusible and binds to albumin and globulins.
The high lipophilicity of elemental mercury in solution in the body allows it to readily cross the blood– brain and placental barriers. In mice, the uptake of mercury across the placenta appears to increase as gestation progresses. Levels of mercury in the foetus are approximately 4 times higher after exposure to elemental mercury vapour than after mercuric chloride administration for mice and 10– 40 times higher for rats. The transport of the mercuric ion is limited at the placental barrier by the presence of high-affinity binding sites.
Mercury distributes to all tissues and reaches peak levels within 24 h, except in the brain, where peak levels are achieved within 23 days. The longest retention of mercury after inhalation of mercury vapour occurs in the brain. Japanese workers who died 10 years after their last exposure to elemental mercury vapours still had high residual levels of mercury in their brains.
While the primary organs of mercury deposition following inhalation exposure to elemental mercury vapours are the brain and kidney, the extent of deposition is dependent upon the duration of exposure and, to a greater extent, the concentration to which the organism is exposed.
The available evidence indicates that the metabolism of all forms of inorganic mercury is similar for humans and laboratory mammals. Once absorbed, elemental and inorganic mercury enter an oxidation– reduction cycle. Elemental mercury is oxidized to the divalent inorganic cation in the red blood cells and lungs. Evidence from animal studies suggests the liver as an additional site of oxidation. Absorbed divalent cation from exposure to mercuric mercury compounds can, in turn, be reduced to the metallic or monovalent form and released as exhaled elemental mercury vapour.
Elimination of mercury occurs primarily through the urine and faeces, with the expired air, sweat, and saliva contributing to a much lesser extent.
2.2
Toxicology studies
ECHA Registration Dossier 5169
2.2.1
Acute toxicity
In an acute oral toxicity study in rats of different age groups, the highest oral toxicity was found in the youngest group of rats (two-week-old sucklings) as indicated by the lowest LD50 value of 35 mg/kg bw mercury chloride (26 mg Hg/kg bw). In six-week-old animals, a LD50 of about 92 mg/kg bw HgCl2 (78 mg Hg/kg bw) was determined, and in older animals (up to 54 weeks) the LD50 values were only about 1.4 times higher than in sucklings (50 mg/kg bw HgCl2 corresponding to 37 mg Hg/kg bw).
The LD50 (rats) was higher than 2000 mg/kg for the test item MISCELA HY-TQS. Since only about 24.8% of mercury are included in the test item, this can be recalculated to > 496 mg/kg mercury.
A concentration level of 27 mg/m3 Hg was lethal in the majority of animals exposed by inhalation for 2 hours, but no death occurred in animals exposed only for 1 hour.
Limited information on acute dermal toxicity in rabbits indicated lethality after application of high dermal doses of mercury from ointments.
Mild to moderate morphological changes were observed in the kidneys of rats at lower oral dose levels in the range of 10.0 and 12.5 mg/kg bw (7.4 and 9.2 mg Hg/kg bw/d). Morphological changes in kidneys were also found in animals treated dermally with high doses of mercury. Biochemistry revealed decreased levels of lactate dehydrogenase (LDH) activity and an increase in serum cholesterol and phosphorus, and hematology showed decreases in red blood cell parameters in the oral study.
2.2.2
Short term toxicity
ECHA Registration Dossier 5169
Repeated dose toxicity, oral:
Data on repeated dose toxicity by the oral route in animals are available. In a NTP study, mice and rats were administered orally by gavage for 2 weeks, 26 weeks or 2 years. The lowest LOAEL of 0.312 mg HgCl2/kg bw/d (0.23 mg Hg/kg bw/d) was identified in the 26-week NTP study in rats based on effects on kidney weights and nephropathy. Results from the subsequent 2-year carcinogenicity study in rats revealed the lowest dose level of 2.5 mg/kg bw/d HgCl2(1.9 mg Hg/kg bw/d) representing also only a LOAEL based on morphological changes of nephropathy.
Repeated dose toxicity, dermal:
There is almost no information available on systemic toxicity resulting from repeated dermal exposure of animals. The evaluation of human literature revealed some information about clinical findings in subjects using skin lightening creams containing mercuric ammonium chloride. It could be concluded that a urinary mercury concentration of 29 µg/l (range 0 -90 µg/l) must be regarded as a LOAEL based on established mercury induced nephrotic syndrome.
However, absorption through the skin is very limited [“... a very small amount of mercury (about 2% of what is taken up by the lungs) enters the body through the skin”], and thus systemic toxicity following repeated dermal exposure appears to be not of major concern.
Repeated dose toxicity, inhalation:
The biological effects of long-time low to moderate exposures to metallic mercury vapours under occupational settings were evaluated in depth by EuroChlor (2009):
It was concluded that with the exception of urinary excretion of N-acetyl-beta-D-glucosamidase (NAG) from the proximal tubular kidney cells, it seems from the review of scientific literature that effects on the central nervous system are the most sensitive indicator of Hg toxicity. It is considered that the toxic effects from high level exposure are sufficiently well known. Sufficient knowledge for defining reasonably tenable occupational exposure limits also seems to be in place. This is based on recent epidemiological studies on cohorts under current or historical low-level exposures. The conclusion of the author of this review, putting a particular emphasis on the latest Ellingsen et al studies encompassing the magnitude of reversibility after cessation or reduction of exposure, there are reasons to support a NOAEL (no adverse effect level) of 30 μg Hg/g creatinine.
2.2.3
Genotoxicity (including mutagenicity)
ECHA Registration Dossier 5169
In vitro and in vivo genotoxicity studies showed equivocal results.
2.2.4
Long term toxicity and carcinogenicity
ECHA Registration Dossier 5169
The evidence for a mutagenic or carcinogenic potential of Hg in both animal (oral exposure) and epidemiological studies (occupational inhalation exposure) is equivocal, and it is so far lacking in humans at low exposure concentrations < 50 µg/g creatinine in urine. The mutagenic or carcinogenic potential of Hg seems to be related to metal induced oxidative stress and thus, if a potential is present in humans, a threshold effects is hypothetically possible.
IARC (1993)
Metallic mercury is not classifiable as to its carcinogenicity to humans (Group 3)
2.2.5
Effects on reproduction
ECHA Registration Dossier 5169
Toxicokinetic animal data has shown that mercury does penetrate the placental barrier and accumulates in the foetus when the mother is exposed to metallic Hg vapour. Even though there are inter-species differences, limited epidemiological studies in humans show that there is a transfer from mother to foetus during Hg vapour exposure. Only a few epidemiological studies have been performed and these were mostly in the field of dentistry. As a whole, the limited data presently available provide no conclusive evidence for occupational exposure to mercury vapour being harmful to reproduction. There is no link to an increase in teratogenic or other adverse pregnancy outcomes.
2.2.6
Neurotoxicity/ delayed neurotoxicity, Special studies where available
European Union
Methylmercury is highly toxic especially to the nervous system. Methylmercury toxicity has been demonstrated at low exposure levels. In adults, the first effects at the lowest doses are nonspecific symptoms such as paresthesia, malaise and blurred vision. This may progress to cerebellar ataxia (clumsiness or unsteadiness), dysarthria (speech disorder), constriction of the visual fields and loss of hearing. With increasing exposure there are signs such as construction of the visual field, deafness, dysarthria and ataxia, and ultimately leading to coma and death.
Methylmercury exhibits severe neurodevelopmental effects. It passes both the placental barrier and the blood-brain barrier. The developing nervous system in unborn and newborn children is the most sensitive target organ. The effects can take place even at exposure levels where the mother remains healthy or suffers only minor symptoms due to mercury exposure. At lower exposure levels, the effects may only become apparent later during the development as psychomotor and mental impairment and persistent pathological reflexes. In infants exposed to high levels of methylmercury during mothers pregnancy, the clinical picture can be indistinguishable from cerebral palsy caused by other factors, the main pattern being microcephaly, hyperreflexia and gross motor and mental impairment, and in rare cases, blindness or deafness. Some studies suggest even small increases in methylmercury exposures may cause adverse effects on the cardiovascular system, thereby leading to increased mortality.
The examples of mercury poisoning in Japan and Iraq have shown on a population scale the severe neurological effects of methylmercury to humans.
ECHA Registration Dossier 5169
Marked cellular degeneration and widespread necrosis were observed in the brains of rabbits following exposures to elemental mercury vapour at 28.8 mg/m3 for durations ranging from 2 to 30 h, whereas exposure of rabbits to mercury vapour at 6 mg/m3 for periods ranging from 1 to 11 weeks produced effects ranging from mild, unspecified pathological changes to marked cellular degeneration and some necrosis in the brain. More serious degenerative changes were observed at longer exposure durations (i.e., 8 and 11 weeks). Mild to moderate pathological changes were observed in the brains after exposure to 0.86 mg/m3 for 12 weeks. Slight tremors and clonus were observed in two of six rabbits exposed for 13 weeks to an elemental mercury vapour concentration of 4 mg/m3. Neurobehavioural deficits were also observed in the offspring of mother monkeys and rats that were exposed to mercury vapours during gestation. Exposure of neonatal rats to elemental mercury vapour at 0.05 mg/m3 for 1 or 4 h/day for 1 week during a period of rapid brain growth (postpartum days 11–17) resulted in subtle behavioural changes when the rats were tested at 4 and 6 months of age. The severity of effect was directly related to the duration of individual exposures.
2.2.7
Summary of mammalian toxicity and overall evaluation
WHO 2021
Elemental mercury and methylmercury are toxic to the central and peripheral nervous system. The inhalation of mercury vapour can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested. Neurological and behavioural disorders may be observed after inhalation, ingestion or dermal application of different mercury compounds. Symptoms include tremors, insomnia, memory loss, neuromuscular effects, headaches and cognitive and motor dysfunction. Mild subclinical signs of central nervous system toxicity can be seen in workers exposed to an elemental mercury level in the air of 20 µg/m3 or more for several years. Kidney and immune effects have been reported. There is no conclusive evidence linking mercury exposure to cancer in humans. Children are especially vulnerable and may be exposed directly by eating contaminated fish. Methylmercury bioaccumulated in fish and consumed by pregnant women may lead to neurodevelopmental problems in the developing foetus. Transplacental exposure is the most dangerous, as the fetal brain is very sensitive. Neurological symptoms include intellectual disability, seizures, vision and hearing loss, delayed development, language disorders and memory loss. In infants and young children, a condition called acrodynia (or “pink disease”), characterized by red and painful extremities with local swelling and intense itching, and which can be accompanied by insomnia, irritability, and sensitivity to light, has been reported to result from chronic mercury exposure
3. Human exposure/risk evaluation
3.1
Food
WHO (2003)
Eating contaminated fish and shellfish is the main source of methylmercury exposure, especially in populations that rely heavily on consumption of predatory fish. Cooking does not eliminate mercury from fish. FAO and WHO guidance exists for national food safety authorities to assess the net health benefits or risks of fish consumption, taking into account the existing information on the benefits of eating fish
3.2
Air
Colombia
Studies conducted in Colombia by the Government of Antioquia in the municipalities of Segovia and Remedios, in the Northeast of the department, found a concentration of mercury of approximately 340 μg/m³ in the air (300 times higher than the guideline of the World Health Organization for public maximum exposure to vapour of mercury).
WHO (2000)
The atmosphere and dental amalgam are the sole sources of exposure to mercury vapour, whereas the diet is the dominant source of methylmercury compounds.
Current levels of mercury in outdoor air, except for regional “hot spots”, are typically in the order of 0.005–0.010 µg/m3 and thus are marginal compared to exposure from dental amalgam. The exposure to mercury from outdoor air at these air levels is not expected to have direct effects on human health.
The LOAELs for mercury vapour are around 15–30 µg/m3.
Applying an uncertainty factor of 20 (10 for uncertainty due to variable sensitivities in higher risk populations and, on the basis of dose–response information, a factor of 2 to extrapolate from a LOAEL to a likely NOAEL), a guideline for inorganic mercury vapour of 1 µg/m3 as an annual average has been established. Since cationic inorganic mercury is retained only half as much as the vapour, the guideline also protects against mild renal effects caused by cationic inorganic mercury. Present knowledge suggests, however, that effects on the immune system at lower exposures cannot be excluded.
3.3
Water
Colombia
Studies conducted in Colombia by the Government of Antioquia in the municipalities of Segovia and Remedios, in the Northeast of the department, reported that approximately 26 to 6,118 ppm of Hg is discharged into rivers by miners in the region. Additionally, the main food of these communities is fish, which has been shown to be affected by the emission of mercury. Studies completed by Corantioquia, the University of Antioquia, and the University of Cartagena have revealed a concentration above 1.06 μg Hg/g in most of the species found in the rivers of the surrounding area.
3.4
Occupational exposure
Colombia
Occupational exposure is the most reported cause of mercury poisoning in Colombia, mining and quarrying occupations have the highest number of cases due to the use of mercury in gold mining. The most frequent notifiers of poisoning cases during the review period were Antioquia, followed by Bogotá, Bolívar, Risaralda, Santander and Valle del Cauca. The highest percentage of intoxications reported were occupational, predominantly miners or stonemasons, with inhalation being the most frequent route of exposure.
3.5
Medical data contributing to regulatory decision
Colombia
According to the National Public Health Surveillance System - SIVIGILA, during 2010 and in the first half of 2011, 201 cases of mercury poisoning were reported in Colombia- 96% of the cases were of occupational or accidental origin as follows: 85% (n = 171) occupational, 11% (n = 22) accidental.
3.6
Public exposure
Colombia
Studies on populations with known exposures to mercury, including occupational and general population exposures, show a link between exposure and adverse health effects. The neuroepidemiological and toxicological study of the Suratá river pollutants carried out in the mining population of that region raised the possible relationship of chronic exposure to mercury with the presence of neurological diseases. It was further reported that the inhabitants of southern Bolívar presented signs of mercury intoxication such as hand tremors, neurological disorders and visual problems, among others. In this region, frequent cases of congenital malformations have also been reported, although without evidence of association with mercury exposure.
3.7
Summary-overall risk evaluation
Colombia
Data in the Colombian notification includes extensive neuro-epidemiological studies in exposed populations (occupational and general population) and studies in different environmental compartments (freshwater, soil, sediment, biota, etc.) and food (fish). Mercury measurements have been made in humans, mainly in workers and communities surrounding mining activities or adjacent to riverine areas.
The evaluation established that mercury is a toxic substance, that when entering the human body produces disorders, mainly at the central nervous system level. The presence of mercury in the air, water, soil and food (mainly fish) in concentrations above the allowed limit has caused a serious public health problem in Colombia. Regions such as the Northeast of Antioquia, the South of Bolívar, Chocó, Santander, Nariño, Caldas, Vaupés carry out artisanal gold mining using mercury for the final extraction of gold form ore. Its use occurs in an indiscriminate and poorly controlled way that has caused environmental contamination and has affected people's health. Exposure to mercury is also increased in industrial areas that use this substance.
European Union
While the European Union’s risk assessment was conducted in the context of the restriction on mercury-containing measuring devices intended for industrial and professional uses, it includes information on the risks associated with mercury that is not limited to those measuring devices and that could support the other Directives and Regulations that comprise the final regulatory action notified by the European Union.
According to the ECHA Committee for Risk Assessment (RAC) Opinion and its background document, mercury and its compounds are highly toxic to humans, ecosystems and wildlife, with amongst others serious chronic irreversible adverse neurotoxic and neurodevelopmental effects. The RAC opinion includes a PBT assessment for mercury-methylmercury concluding and equivalent level of concern in terms of persistency, due to mercury cycling and methylation versus demethylation rates under anaerobic conditions, as well as the clear potential for bioaccumulation and toxicity identified for methylmercury.
4. Environmental fate and effects
4.1
Fate
European Union
Once released to the environment, mercury persists in the environment, where it circulates between air, water, sediments, soil and biota in various forms. Mercury can be transformed to methylmercury, the most toxic form, which biomagnifies especially in the aquatic food chain.
4.1.1
Soil
European Union
Mercury in soil is mostly bound to bulk organic matter and is susceptible to wash out in runoff only when attached to suspended soil or humus. Mercury has a long retention time in soil and as a result, the mercury accumulated in soil may continue to be released to surface waters and other media for long period of time, possibly hundreds of years.
4.1.2
Water
UNEP (2002)
From open ocean studies, it is apparent that elemental mercury, dimethylmercury and, to a lesser extent, methylmercury are common constituents of the dissolved mercury pool in deep ocean waters. In open ocean surface waters dimethylmercury is lacking, maybe as a result of decomposition in the presence of light and an additional potential loss via evapouration from the water surface. Results suggest that low oxygen conditions are not necessary for the formation of dimethylmercury in the open oceans. This contrasts with temperate lake waters where methylmercury is more commonly occurring than dimethylmercury. Studies in freshwater and estuarine environments have shown that methylation of mercury is primarily taking place under low oxygen conditions and mainly by sulphate-reducing bacteria. Here methylmercury is the product of methylation of ionic mercury.
4.1.3
Air
European Union
Once released into the atmosphere, mercury can undergo long-range atmospheric transport, hence the atmosphere is the most important pathway for the worldwide dispersion and transport of mercury in the environment. Elemental mercury in the atmosphere can undergo transformation into inorganic mercury forms, providing a significant pathway for deposition of emitted elemental mercury. Mercury vapour has an atmospheric residence time that is between 0.4 and 3 years. Emitted mercury vapour is converted to soluble forms, these soluble forms have residence times of a few weeks. Soluble forms of mercury are deposited by rain into soil and water.
4.1.4
Bioconcentration
European Union
The bioconcentration factor (BCF) of methylmercury in fish can range from 8140 to 85 700. Methylmercury' biomagnification is very high with a typical increase of more than 1 log unit between trophic levels, and the bioaccumulation factor BAF can reach values 107 times higher than the concentration measured in water.
4.1.5
Persistence
European Union
Elemental mercury can be considered persistent, as it is not removed from the environment through degradation processes and will always be potentially available for cycling into methylmercury (through complex processes under appropriate conditions, even at equilibrium there is a near constant level of methylmercury in sediment). Any increase in the environmental pool of inorganic mercury will provide an additional source of methylmercury, and this source will persist for many years.
4.2
Effects on non-target organisms
N/A
4.2.1
Terrestrial vertebrates
European Union
As in humans, mercury exposure of animals may result in severe neurological effects. These effects were clearly seen in the Minamata poisoning, where birds experienced severe difficulties in flying, and domestic animals, especially cats, showed signs of severe neurological intoxication. In birds, methylmercury has been associated with eggshell thinning in the 1950's and 1960's. Methylmercury was used as a fungicidal seed dressing, and severe poisoning of wildlife was observed in Scandinavia and North America. Populations of pheasants and other seed-eating birds, as well as birds of prey were drastically reduced and, in some areas, nearly disappeared. Adverse effects of mercury on reproduction can occur at egg concentrations as low as 0.05 to 2.0 mg/kg (wet weight). Eggs of certain Canadian species were reported to be in this range, and concentrations in the eggs of several other Canadian species were said to continue to increase and were approaching these levels.
4.2.2
Aquatic species
European Union
To adult fish, direct exposure to methylmercury from the surrounding water is generally not a serious concern. However, evidence suggests that mercury exposure to early life stages of some fish can affect growth, development and hormonal status at levels within a factor of 10 of levels encountered in “pristine” lakes. Effects from indirect exposure via dietary uptake and maternal transfer of methylmercury to eggs and developing embryos might be of concern.
4.2.3
Honeybees and other arthropods
Not available
4.2.4
Earthworms
Not available
4.2.5
Soil microorganisms
European Union
Mercury is toxic to micro-organisms and has long been used to inhibit the growth of bacteria in laboratory experiments. Evidence suggests that mercury is responsible for a reduction of micro-biological activity vital to the terrestrial food chain in soils over large parts of Europe – and potentially in many other places in the world with similar soil characteristics.
4.2.6
Terrestrial plants
UNEP (2002)
Terrestrial plants are fairly insensitive to the toxic effects of mercury compounds. Mercury is, however, accumulated in higher plants, especially in perennials. The primary effect observed in plants is associated with root tips.
5. Environmental exposure/risk evaluation
5.1
Terrestrial vertebrates
UNEP (2002)
On the global scale, the Arctic region has been in focus because of mercury’s particular tendency to long-range transport. It is important to acknowledge, however, that impacts of mercury are by no means restricted to the Arctic region. The same food web characteristics and similar dependence on a mercury contaminated food source are found in specific ecosystems and human communities in many countries around the world, particularly where a fish diet is predominant. Consequently, fish-eating birds and mammals are more highly exposed to mercury than any other known denizens of the aquatic ecosystem.
5.2
Aquatic species
European Union
The elimination of methylmercury from fish is very slow, which causes fish to accumulate methylmercury over time. Moreover, methylmercury biomagnifies throughout the many aquatic trophic levels. The highest levels in the aquatic food web are found in fish that are apical predators of older age (such as king mackerel, pike, shark, swordfish, walleye, barracuda, large tuna, scabbard, and marlin) and fish-consuming mammals such as seals and toothed whales.
5.3
Honeybees
Not available
5.4
Earthworms
Not available
5.5
Soil microorganisms
Not available
5.6
Summary – overall risk evaluation
European Union
Mercury occurs both naturally and as an introduced contaminant in the environment. Anthropogenic emissions have widespread impacts on human and environmental health.
Mercury is a global pollutant that cannot be broken down in the environment to any harmless form. Once emitted, mercury enters the complex biogeochemical cycle. After intensive use of mercury over many years mercury can be found in almost all environmental compartments, like the atmosphere, soil and water systems and in biota all over the world. The formation of methylmercury and subsequent biomagnification in food chains considerably increases risks posed by mercury causing, among others, chronic intoxications of people, although it is difficult to determine the proportion of mercury contaminating the environment, which is turned into methylmercury. Therefore, it is necessary to reduce the risk of exposure to mercury for humans and the environment. The key, long term benefit of reducing mercury emissions will be decreased levels of mercury in the environment. This, in turn, will lead to lower levels of human exposure to mercury, including methylmercury in fish, with resultant health benefits. It will also reduce the impacts of mercury on soils and biodiversity.
Annex 2: Details on final regulatory actions reported
Colombia
1.
Effective date(s) of entry into force of actions
15 July 2013
Reference to the regulatory document
Ley 1658 de 2013 (Anexo I)
DIARIO OFICIAL AÑO CXCLIX. N. 48.852. 15, JULIO, PAG.6
http://www.suin-juriscol.gov.co/viewDocument.asp?ruta=Leyes/1685943
2.
Succinct details of the final regulatory action(s)
Based on Law 1658 of 15 July 2013, the government of Colombia prohibited the marketing and use of mercury. The regulation eradicates the use of mercury in the national territory in: 1) all industrial and production processes within a period not exceeding 10 years (till 15 July 2023), and 2) for mining within a maximum period of 5 years (till 15 July 2018). Currently the deadline for industrial uses other than mining has not been met; this is the reason why the use of mercury in the production of dental amalgam will continue until 15 July 2023.
3.
Reasons for action
The government of Colombia prohibited the marketing and use of mercury under Law 1658 of 15 July 2013. It was determined that in order to protect and safeguard the human health and preserve renewable natural resources and the environment, the use, import, production, marketing, handling, transportation, storage, final disposal and release into the environment of mercury in industrial activities, whatever they may be, must be regulated throughout the national territory.
Specifically, Article 3 of the law establishes the measures to reduce and eliminate the use of mercury in the country as follows: "Article 3. Reduction and elimination of the use of mercury. The Ministries of Environment and Sustainable Development; Mines and Energy; Health and Social Protection and Work, will establish the necessary regulatory measures that will allow to reduce and eliminate, in a safe and sustainable way, the use of mercury in the different industrial activities of the country. Eradicate the use of mercury throughout the national territory, in all industrial and productive processes within a period not exceeding ten (10) years and for mining within a maximum period of five (5) years.
4.
Basis for inclusion into Annex III
The final regulatory action was taken to protect human health and the environment. The regulatory action was based on a risk evaluation taking into account the prevailing conditions in Colombia.
4.1
Risk evaluation
According to the evaluation related to human health and the environment, the following information was identified (UNEP/FAO/RC/CRC.19/11 and UNEP/FAO/RC/CRC.19/INF/24):
(a) The data includes extensive neuro-epidemiological studies in exposed populations (occupational and general population) and studies in different environmental compartments (freshwater, soil, sediment, biota, etc.), food (fish), with a view of establishing the levels of mercury and the perception of risk, and generating scientific, regulatory and technical evidence on the mercury problem both at the national and international level of the health sector and other related sector. Mercury measurements have been made in humans, mainly in workers and communities surrounding mining activities or adjacent to riverine areas.
(b) The evaluation conducted establish that mercury is a toxic substance, that when entering the human body produces disorders, mainly at the central nervous system level. The presence of mercury in the air, water, soil and food (mainly fish) in concentrations above the allowed limit has caused a serious public health problem in Colombia. Regions such as the Northeast of Antioquia, the South of Bolívar, Chocó, Santander, Nariño, Caldas, Vaupés, among others, carry out artisanal gold mining and for the final extraction of this precious metal, mercury is used. Its use occurs in an indiscriminate and poorly controlled way, a situation that has caused environmental contamination and has affected people's health. Exposure to mercury is also increased in industrial areas that use this substance.
(c) Studies conducted by the Government of Antioquia in the municipalities of Segovia and Remedios, in the Northeast of the department, found a concentration of mercury of approximately 340 μg/m³ in the air (300 times higher than the guideline of the World Health Organization for public maximum exposure to vapour of mercury).
(d) Approximately 26 to 6,118 ppm of Hg is discharged into rivers by miners in the region. Additionally, the main food of these communities is fish, which has been shown to be affected by the emission of mercury. Studies completed by Corantioquia, the University of Antioquia, and the University of Cartagena have revealed a concentration above 1.06 μg Hg/g in most of the species found in the rivers of the surrounding area.
(e) Mercury contamination in Colombia is mostly caused by its use in the extraction of gold from ore. In this process, elemental mercury is added to gold containing ores and minerals to form a gold amalgam. Mercury used this way may spill into water bodies and the environment. Subsequently, the gold amalgam is recovered and burned in the open air to extract the gold, which release toxic mercury vapours into the atmosphere. All these activities are performed very close to the miners' households, in such a way that families breathe a large part of the volatilized mercury vapour. Even remote populations can be affected by the mobilization of this substance (Protocol for Surveillance and Control of Acute Mercury Poisoning. INF/30, Annex III).
(f) Studies on populations with known exposures to mercury, including occupational and general population exposures, show a link between exposure and adverse health effects (Fawer et al 1983, Piikivi 1989, Marh et al 1987). The neuroepidemiological and toxicological study of the Suratá river pollutants carried out in the mining population of that region (Santander, 1992) raised the possible relationship of chronic exposure to mercury with the presence of neurological diseases. Tirado et al (2000) suggest that this form of exposure can cause neuropsychological and behavioural deficits in the population. In 1995, Olivero et al reported that the inhabitants of southern Bolívar presented signs of mercury intoxication such as hand tremors, neurological disorders and visual problems, among others. In this region, frequent cases of congenital malformations have also been reported, although without evidence of association with mercury exposure.
(g) According to National Public Health Surveillance System - SIVIGILA, during 2010 and in the first half of 2011, 201 cases of mercury poisoning were reported in Colombia- 96% of the cases were of occupational or accidental causes as follows: 85% (n = 171) occupational, 11% (n = 22) accidental.
(h) Occupational exposure is the most reported cause of mercury poisoning in Colombia. Mining and quarrying occupations have the highest number of cases due to the use of mercury in gold mining. The most frequent notifiers of poisoning cases during the review period were Antioquia, followed by Bogotá, Bolívar, Risaralda, Santander and Valle del Cauca. The highest percentage of intoxications reported were occupational, predominately miners or stonemasons, with inhalation being the most frequent route of exposure (Scientific, Regulatory and Technical Evidence on the Mercury Problem at the Level National and International Health Sector and Other Related Sectors. Revision Systematics of Literature, INF/30, Annex IV).
(i) Some population groups may need special consideration in relation to exposure to mercury, since they have a greater probability of exposure to dangerous levels, or because carriers of disease, the intoxication effects can be exacerbated:
(i) Workers exposed to mercury;
(ii) General population next to sources of mercury contamination (mines, industries);
(iii) Populations in areas contaminated by mercury, especially indigenous and riverine, whose main source of proteins is fish;
(iv) People using mercury-containing medications for a long time;
(v) People with central nervous system diseases, patients with chronic kidney and bronco pulmonary failure;
(vi) Pregnant women and toddlers.
4.2
Criteria used
Risks to human health and the environment.
Relevance to other States and Region
The notification states that mercury can be used in other countries for the manufacture of products with added mercury and in gold extraction, mainly in developing countries. Therefore, the considerations leading to the final regulatory action being taken are expected to be applicable to other geographical area where mercury is used in similar conditions.
5.
Alternatives
None reported
6.
Waste management
None reported
7.
Other
None reported
European Union
1.
Effective date(s) of entry into force of actions
(a) Directive 2006/66/EC entered into force on 26 September 2006;
(b) Directive 2007/51/EC started to apply on 3 April 2009;
(c) Commission Regulation (EC) No 552/2009 entered into force 27 June 2009;
(d) Directive 2011/65/EU entered into force 21 July 2011;
(e) Commission Regulation (EU) No 847/2012 started to apply on 10 April 2014;
(f) Regulation (EU) 2017/852 entered into force on 13 June 2017.
Reference to the regulatory document
Directive 2006/66/EC of the European Parliament and of the Council of 6 September 2006 on batteries and accumulators and waste batteries and accumulators and repealing Directive 91/157/EEC.
http://data.europa.eu/eli/dir/2006/66/2018-07-04
Directive 2007/51/EC of the European Parliament and of the Council of 25 September 2007 amending Council Directive 76/769/EEC relating to restrictions on the marketing of certain measuring devices containing mercury.
http://data.europa.eu/eli/dir/2007/51/oj
Commission Regulation (EC) No 552/2009 of 22 June 2009 amending Regulation (EC) No1907/2006 of the European Parliament and of the Council on the Registration, Evaluation,Authorisation and Restriction of Chemicals (REACH) as regards Annex XVII.
http://data.europa.eu/eli/reg/2009/552/oj
Commission Regulation (EU) No 847/2012 of 19 September 2012 amending Annex XVII to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards mercury.
http://data.europa.eu/eli/reg/2012/847/oj
Directive 2011/65/EU of the European Parliament and of the Council of 8 June 2011 on the restriction of the use of certain hazardous substances in electrical and electronic equipment.
http://data.europa.eu/eli/dir/2011/65/2020-09-01
Regulation (EU) 2017/852 of the European Parliament and of the Council of 17 May 2017 on mercury, and repealing Regulation (EC) No 1102/2008.
http://data.europa.eu/eli/reg/2017/852/oj
2.
Succinct details of the final regulatory action(s)
The use of mercury as an industrial chemical is severely restricted in the European Union pursuant to Regulation (EU) 2017/852 on mercury, Regulation (EC) 1907/2006 (REACH), Directive 2011/65/EU (RoHS) and Directive 2006/66/EC (batteries and accumulators). More specifically:
(a) In 2006, Directive 2006/66/EC introduced a prohibition on the placing on the market of batteries and accumulators containing mercury;
(b) In 2007, Directive 2007/51/EC introduced a restriction under Directive 76/769/EEC on the placing on the market of mercury in fever thermometers and in other measuring devices intended for sale to the general public;
(c) Regulation (EC) No 1907/2006 (REACH) repealed Directive 76/769/EEC. Commission Regulation (EC) No 552/2009 amended Annex XVII to REACH by incorporating in entry 18.a the restrictions on certain measuring devices containing mercury that was adopted under Directive 2007/51/EC;
(d) In 2011, Directive 2011/65/EU (RoHS) established a restriction on the placing on the market of electric and electronic equipment to a maximum concentration value of 0.1% of mercury, allowing exemptions for certain applications for a limited time period;
(e) Commission Regulation (EU) No 847/2012 amended Annex XVII to REACH by incorporating in entry 18.a. a restriction on the placing on the market of mercury-containing and mercury- using measuring devices intended for industrial and professional uses. The restriction started to apply from 10 April 2014;
(f) Regulation (EU) 2017/852 on mercury was adopted in May 2017. This regulation complements the European Union acquis and lays down the provisions that are needed to ensure the complete alignment of the European Union acquis with the Minamata Convention on Mercury establishing measures and conditions concerning the use and storage of and trade in mercury, mercury compounds and mixtures of mercury, and the manufacture and use of and trade in mercury-added products, and the management of mercury waste.
3.
Reasons for action
The final regulatory action has been taken in order to protect human health and the environment and further explains that mercury is a chemical of global concern owing to its long-range atmospheric transport, its persistence in the environment once anthropogenically introduced, its ability to bioaccumulate in ecosystems and its significant negative effects on the environment and on human health, which include significant adverse neurological and other health effects, with particular concerns expressed about its harmful effects on infants and unborn children. Mercury can be transformed to methylmercury, the most toxic form, which biomagnifies especially in the aquatic food chain, making populations and wildlife with a high intake of fish and seafood particularly vulnerable.
4.
Basis for inclusion into Annex III
The final regulatory action was taken to protect human health and the environment. The regulatory action was based on a risk evaluation taking into account the prevailing conditions of use of mercury in the European Union.
4.1
Risk evaluation
According to the evaluation related to human health and the environment, the following information was identified (UNEP/FAO/RC/CRC.19/11 and UNEP/FAO/RC/CRC.19/INF/22):
(a) While this risk assessment was conducted in the context of the restriction on mercury-containing measuring devices intended for industrial and professional uses, it includes information on the risks associated with mercury that is not limited to those measuring devices and that could support the other Directives and Regulations that comprise the final regulatory action notified by the European Union;
(b) According to the ECHA Committee for Risk Assessment (RAC) Opinion and its background document, mercury and its compounds are highly toxic to humans, ecosystems and wildlife, with amongst others serious chronic irreversible adverse neurotoxic and neurodevelopmental effects. The RAC opinion does not explicitly conduct a PBT assessment for mercury-methylmercury, but it does note that it should be considered with an equivalent level of concern in terms of persistency, due to mercury cycling and methylation versus demethylation rates under anaerobic conditions, as well as the clear potential for bioaccumulation and toxicity identified for methylmercury;
(c) The hazard and fate of mercury and its compounds are described in numerous peer-reviewed reports, which were referenced in the Documentation provided:
(i) ‘Global Mercury Assessment’, published by UNEP in 2002 (and UNEP 2008a and b);
(ii) ‘Methylmercury’ (WHO, 1990);
(iii) ‘Risks to Health and the Environment Related to the Use of Mercury Products’ prepared for the Commission by RPA in 2002;
(d) It is estimated that 3.5–7.6 tonnes of mercury are placed on the market in mercury containing measuring devices in 2010. These amounts are used to estimate the maximum potential for mercury emissions to the environment that might ultimately occur. This assumption is considered appropriate because of an estimated low separate collection rate of mercury waste and resulting inadequate waste treatment of a substantial part of the devices. This inappropriate waste collection leads in the long term to a relatively high share of mercury used in these devices being released to the environment. For measuring equipment using mercury (porosimeters, mercury probes used for capacitance-voltage determinations and mercury electrodes used in voltammeters) the total use is 5–15 tonnes per year (mostly porosimeters 5–14 tonnes per year). It should be noted that these figures are the amount of mercury the laboratories purchase and cannot be used to estimate maximum potential for emission as is the case for the measuring equipment containing mercury. To estimate emissions several additional factors need to be considered. These include number of measurements carried out, practices to purify and regenerated used mercury and the risk management measures and operational conditions applied to control the emissions and exposures;
(e) The total mercury consumption in Europe was in 2007 estimated to be 320–530 tonnes. 160–190 tonnes of the total amount were used in the chlor-alkali production and 90–110 were used in dental amalgams. The amount used in mercury measuring devices thus equals about 4% of the total, while the restricted devices will be lower due to the large use in porosimeters;
(f) Once released to the environment, mercury persists in the environment, where it circulates between air, water, sediments, soil and biota in various forms. Mercury can be transformed to methylmercury, the most toxic form, which biomagnifies especially in the aquatic food chain, making populations and wildlife with a high intake of fish and seafood particularly vulnerable;
(g) Several existing pieces of legislation in the European Union abate the risks arising from mercury in different stages of the life cycle of measuring devices. However, none of the measures currently in place is sufficient to remove the concern fully, although there is a difference between their observed effectiveness with regard to measuring devices containing mercury and measuring devices using mercury;
(h) The emissions from mercury measuring devices, although relatively small, contribute to the overall emissions of mercury to the environment and thereby also to the exposure of species and of humans via the environment. Therefore, measuring devices containing or using mercury are of concern.
4.2
Criteria used
Risks to human health and the environment
Relevance to other States and Region
The notification states that similar human health and environmental problems are likely to be encountered in other regions where the substance is used, particularly in developing countries and especially for women and children, and, through them, future generations.
5.
Alternatives
None reported.
6.
Waste management
Regulation (EU) 2017/852 on mercury was adopted in May 2017. This regulation complements the European Union acquis and lays down the provisions that are needed to ensure the complete alignment of the European Union acquis with the Minamata Convention on Mercury establishing measures and conditions concerning the use and storage of and trade in mercury, mercury compounds and mixtures of mercury, and the manufacture and use of and trade in mercury-added products, and the management of mercury waste.
7.
Other
None reported.
Annex 3: Addresses of designated national authorities
Colombia
Rotterdam Convention Designated national authority for industrial chemicals (DNA C)
Name: Ms. Andrea Patricia Soler Galindo
Job title: Coordinadora Grupo Desarrollo y Salud
Department: Subdirección de Salud Ambiental
Institution: Ministerio de Salud y Protección Social
Postal address: Carrera 13 # 32 - 76 Piso 14, Edificio Urano
Bogotá D.C.
Colombia
Phone: +57 1 330 5000 ext. 1241
Email:
[email protected];
[email protected]
European Union
Rotterdam Convention Designated national authority for industrial chemicals and pesticides (DNA CP), Rotterdam Convention Official contact point (OCP).
Name: Mr. Juergen Helbig
Job title: International Chemicals Policy Coordinator
Department: DG Environment, Unit ENV.B2 - Safe and Sustainable Chemicals
Institution: European Commission
Postal address: 1049 Brussels
Belgium
Phone: +32 2 298 8521
Fax: +32 2 298 8874
Email:
[email protected]
C Industrial chemicals
CP Pesticides and industrial chemicals
P Pesticides
Annex 4: References
1. Regulatory actions
Colombia
Ley 1658 de 2013 (Anexo I)
DIARIO OFICIAL AÑO CXCLIX. N. 48.852. 15, JULIO, PAG.6
http://www.suin-juriscol.gov.co/viewDocument.asp?ruta=Leyes/1685943
European Union
Directive 2006/66/EC of the European Parliament and of the Council of 6 September 2006 on batteries and accumulators and waste batteries and accumulators and repealing Directive 91/157/EEC.
http://data.europa.eu/eli/dir/2006/66/2018-07-04
Directive 2007/51/EC of the European Parliament and of the Council of 25 September 2007 amending Council Directive 76/769/EEC relating to restrictions on the marketing of certain measuring devices containing mercury
http://data.europa.eu/eli/dir/2007/51/oj
Commission Regulation (EC) No 552/2009 of 22 June 2009 amending Regulation (EC) No1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards Annex XVII
http://data.europa.eu/eli/reg/2009/552/oj
Commission Regulation (EU) No 847/2012 of 19 September 2012 amending Annex XVII to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards mercury
http://data.europa.eu/eli/reg/2012/847/oj
Directive 2011/65/EU of the European Parliament and of the Council of 8 June 2011 on the restriction of the use of certain hazardous substances in electrical and electronic equipment.
http://data.europa.eu/eli/dir/2011/65/2020-09-01
Regulation (EU) 2017/852 of the European Parliament and of the Council of 17 May 2017 on mercury, and repealing Regulation (EC) No 1102/2008.
http://data.europa.eu/eli/reg/2017/852/oj
2. Supporting Documentation
Mercury: notifications of final regulatory action. UNEP/FAO/RC/CRC.19/11
Supporting documentation provided by Columbia. UNEP/FAO/RC/CRC.19/INF/22
Supporting documentation provided by the European Unions. UNEP/FAO/RC/CRC.19/INF/24
3. Other Documents
ECHA registration dossier 5169 (Mercury), accessed at: https://echa.europa.eu/registration-dossier/-/registered-dossier/5169
IARC (1993), IARC Monographs on the Evaluation of Carcinogenic Risks to humans, Beryllium, Cadmium, Mercury and Exposures in Glass Manufacturing Industry, Volume 58. https://publications.iarc.fr/_publications/media/download/1954/ed5ada49ff1536d1474abdb982ee69583dbf1bc2.pdf
IRIS (1995a). Mercury elemental; CASRN 7439-97-6. https://cfpub.epa.gov/ncea/iris/iris_documents/documents/subst/0370_summary.pdf
IRIS(1995b). Mercuric chloride (HgCl2); CVASRN 787-94-7. https://cfpub.epa.gov/ncea/iris/iris_documents/documents/subst/0692_summary.pdf
IRIS (2001). Methylmercury (MeHg); CASRN 22967-92-6. https://cfpub.epa.gov/ncea/iris/iris_documents/documents/subst/0073_summary.pdf
SCOEL/SUM/84 (2007). Recommendation from the Scientific Committee on Occupational Exposure Limits for elemental mercury and inorganic divalent mercury compounds. May 2007. http://ec.europa.eu/social/BlobServlet?docId=3852&langId=en
UNEP (2002): Global Mercury Assessment. UN Environment Programme, Chemicals Branch, Geneva, Switzerland. https://www.unep.org/globalmercurypartnership/resources/report/global-mercury-assessment-2002
UNEP (2008): The Global Atmospheric Mercury Assessment: Sources, Emissions and Transport. UN Environment Programme, Chemicals Branch, Geneva, Switzerland. https://www.unep.org/globalmercurypartnership/resources/report/global-atmospheric-mercury-assessment-sources-emissions-and-transport-2008.
UNEP (2013): Global Mercury Assessment 2013: Sources, Emissions, Releases and Environmental Transport. UNEP Chemicals Branch, Geneva, Switzerland. Global Mercury Assessment 2013: Sources, emissions, releases, and environmental transport (unep.org)
UNEP (2017). Global mercury supply, trade and demand. United Nations Environment Programme, Chemicals and Health Branch. Geneva, Switzerland. https://www.unep.org/resources/report/global-mercury-supply-trade-and-demand
UNEP (2019): Global Mercury Assessment 2018. UN Environment Programme, Chemicals and Health Branch, Geneva, Switzerland. https://www.unep.org/resources/publication/global-mercury-assessment-2018?_ga=2.172454499.1370957274.1702051132-948088036.1661281591
WHO (2000). Air quality guidelines for Europe, 2nd ed.. World Health Organization. Regional Office for Europe. https://iris.who.int/handle/10665/107335
WHO (2003). Elemental mercury and inorganic mercury compounds: human health aspects, Concise International Chemical Assessment Document 50. World Health organization. https://www.inchem.org/documents/cicads/cicads/cicad50.htm
WHO (2021). Exposure to mercury: a major public health concern, second edition. Preventing disease through healthy environments. World Health Organization. https://www.who.int/publications/i/item/9789240023567
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