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Data: Robust

Thimerosal

IMAGE SOURCE: PubChem

SEARCH PRODUCTS

Other Concerns

Use restrictions (high), Neurotoxicity (high), Endocrine disruption (low), Persistence and bioaccumulation (high), Non-reproductive organ system toxicity (high), Ecotoxicology (low), and Occupational hazards (high)

SYNONYMS

● ETHYL(2-(MERCAPTO-K S)BENZOATE(2-)-K O)- SODIUM MERCURATE(1-)
● ETHYL(2-(MERCAPTPO-K S)BENZOATO(2-)-K O)- SODIUM MERCURATE(1-)
● ETHYL(2-MERCAPTOBENZOATO-S)MERCURY, SODIUM SALT
● MERCURATE(1), ETHYL[2MERCAPTOBENZOATO(2)O,S], SODIUM
● MERCURATE(1-), ETHYL(2-(MERCAPTO-K S)BENZOATE(2-)-K O)-, SODIUM
● MERCURATE(1-), ETHYL(2-(MERCAPTPO-K S)BENZOATO(2-)-K O)-, SODIUM
● MERCURATE(1-), ETHYL[2-(MERCAPTO-.KAPPA.S)BENZOATO(2-)-.KAPPA.O]-, SODIUM
● SODIUM ETHYLMERCURITHIOSALICYLATE
● SODIUM MERCURATE(1-), ETHYL(2-(MERCAPTO-K S)BENZOATE(2-)-K O)-
● SODIUM MERCURATE(1-), ETHYL(2-(MERCAPTPO-K S)BENZOATO(2-)-K O)-
● SODIUM SALT ETHYL(2-MERCAPTOBENZOATO-S)MERCURY
● THIMEROSAL
● THIOMERSAL

Unacceptable

Unacceptable: EWG VERIFIED products cannot contain this ingredient


Thimerosal is a mercury-based preservative used in some vaccines and cosmetics. According to FDA, 'Mercury compounds are readily absorbed through the skin on topical application and tend to accumulate in the body. They may cause allergic reactions, skin irritation, or neurotoxic manifestations.' Mercury is considered particularly toxic to the developing brain during pregnancy, infancy and childhood. FDA has banned the use of mercury compounds in all cosmetics except those used around the eyes, where levels are limited to 65 parts per million (ppm). In 2007 the use of mercury in all cosmetics was banned in Minnesota.

Common concerns

See how this product scores for common concerns.

  • LOW
    Cancer
  • MODERATE
    Allergies & Immunotoxicity
  • MODERATE
    Developmental and Reproductive Toxicity
  • HIGH
    Use Restrictions

Ingredient concerns

  • CONCERNS
  • DATA SOURCES

Products with this Ingredient

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Organ system toxicity (non-reproductive)

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CONCERN REFERENCE
Known human respiratory toxicantEPA Hazardous Air Pollutants
Classified as expected to be toxic or harmfulEnvironment Canada Domestic Substance List
Classified as toxic or harmfulCPS&Q - Classification & Labelling
Limited evidence of kidney toxicityNational Library of Medicine HazMap
Limited evidence of sense organ toxicityScorecard.org Toxicity Information
reproductive - weight of evidence unknown/unassessed/unreview: published lit review or major tox studyNational Library of Medicine HazMap

Persistence and bioaccumulation

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CONCERN REFERENCE
Persistent, bioaccumulative in wildlife and humansEPA Toxic Release Inventory PBTs
Persistent, bioaccumulative in wildlife and humansNational Library of Medicine HazMap
Persistent, bioaccumulative in wildlifeEPA PBTs - Waste Minimization Program (RCRA)
Persistent, bioaccumulative in wildlifeGreat Lakes BTS (Binational Toxics Strategy) PBTs
Persistent, bioaccumulative in wildlifeCanada PBTs - Accelerated Reduction/Elimination of Toxics (ARET)
Persistent, bioaccumulative in wildlifeNational Library of Medicine HazMap
Not suspected to be bioaccumulativeEnvironment Canada Domestic Substance List

Neurotoxicity

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CONCERN REFERENCE
Known human nervous system toxicantOpen scientific literature
Limited evidence of any toxicityOpen scientific literature
nervous system - weight of evidence unknown/unassessed/unreview: published lit review or major tox studyNational Library of Medicine HazMap

Use restrictions

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CONCERN REFERENCE
Violation of government restrictions - Banned or found unsafe for use in cosmeticsCanada - Prohibited and Restricted Cosmetics Ingredients
Restricted in cosmetics (recommendations or requirements) - use, concentration, or manufacturing restrictions - Restricted for use in cosmetics by the FDA (US)U.S. - Ingredients Prohibited and Restricted in Cosmetics by FDA Regulations

Occupational hazards

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CONCERN REFERENCE
Allowed workplace exposures restricted to low dosesCPS&Q - Classification & Labelling
Strong evidence of occupational hazardsCPS&Q - Classification & Labelling

Developmental/reproductive toxicity

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CONCERN REFERENCE
Possible human developmental toxicantCalifornia EPA Proposition 65
Limited evidence of any toxicityOpen scientific literature
Limited evidence of reproductive toxicityNational Library of Medicine HazMap
Limited evidence of reproductive toxicityCPS&Q - Classification & Labelling
Limited evidence of reproductive toxicityScorecard.org Toxicity Information

Allergies/immunotoxicity

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CONCERN REFERENCE
Limited evidence of immune system toxicity or allergiesScorecard.org Toxicity Information
Limited evidence of immune system toxicity or allergiesNational Library of Medicine HazMap

Endocrine disruption

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CONCERN REFERENCE
Limited evidence of endocrine disruptionScorecard.org Toxicity Information
endocrine - weight of evidence unknown/unassessed/unreview: published lit review or major tox studyOur Stolen Future Endocrine Disruptors
endocrine - weight of evidence unknown/unassessed/unreview: published lit review or major tox studyIllinois EPA Chemicals Associated with Endocrine System

Cancer

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CONCERN REFERENCE
Mutagen - limited evidenceCPS&Q - Classification & Labelling
Limited or incomplete evidence of cancer according to safety/hazard data – government assessment cannot classify as human carcinogen due to data gapsInt'l Agency for Research on Cancer (IARC) - Carcinogens
Limited or incomplete evidence of cancer according to safety/hazard data – government assessment cannot classify as human carcinogen due to data gapsEPA Integrated Risk Information System (IRIS)

Ecotoxicology

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CONCERN REFERENCE
Wildlife and environmental toxicityCPS&Q - Classification & Labelling
Wildlife and environmental toxicityEPA Clean Water Act - Priority Pollutants
Suspected to be an environmental toxin and be persistent or bioaccumulativeEnvironment Canada Domestic Substance List
Wildlife and environmental toxicityEuropean Union - Water Framework Directive
Wildlife and environmental toxicityIllinois EPA Chemicals Associated with Endocrine System
Suspected to be an environmental toxinEnvironment Canada Domestic Substance List

Data gaps

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CONCERN REFERENCE
Insufficient data to determine safetyEPA Integrated Risk Information System (IRIS)
307891 studies in PubMed science library may include information on the toxicity of this chemicalNLM PubMed

Miscellaneous

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CONCERN REFERENCE
Occupational hazards related to handlingCPS&Q - Classification & Labelling
  • EPA (U.S. Environmental Protection Agency). 2005. Office of Air. The 112(b)1 Hazardous Air Pollutants List (as modified). Last modified: 12 Dec 2005.
  • EC (Environment Canada). 2008. Domestic Substances List Categorization. Canadian Environmental Protection Act (CEPA) Environmental Registry.
  • CPS&Q (Consumer Products Safety & Quality) formely known as ECB (European Chemicals Bureau). 2008. Classification and Labelling: Chemicals: Annex VI of Directive 67/548/EEC through the 31st ATP.
  • NLM (National Library of Medicine). 2006. HazMap — Occupational Exposure to Hazardous Agents.
  • ED (Environmental Defense). 2006. Scorecard _ The Pollution Information Site. http://www.scorecard.org.
  • EPA (U.S. Environmental Protection Agency). 1999. Toxics Release Inventory Program. PBT Chemical Rule.
  • EPA (U.S. Environmental Protection Agency). 1998. Resource Conservatin and Recovery Act (RCRA) Waste Minimization Program - priority chemicals for elimination or reduction.
  • Great Lakes BTS (Binational Toxics Strategy). 1997. Canada-United States Strategy for the Virtual Elimination of Persistent Toxic Substances in the Great Lakes. Appendix I - Level 1 and Level 2 substances.
  • EC (Environment Canada). 1994. Accelerated Reduction/Elimination of Toxics (ARET). ARET substance list of persistent, bioaccumulative and toxic chemicals.
  • Open scientific/peer reviewed literature
  • Health Canada. 2007. List of Prohibited and Restricted Cosmetic Ingredients. Canada's Cosmetic Ingredient Hotlist. March 2007.
  • FDA (U.S. Food and Drug Administration), 2006. Ingredients Prohibited and Restricted by FDA Regulations. FDA Center for Food Safety and Applied Nutrition, Office of Cosmetics and Colors. Downloaded from http://www.cfsan.fda.gov/~dms/cos-210.html.
  • California EPA (California Environmental Protection Agency). 9/2008. Office of Environmental Health Hazard Assessment. Safe Drinking Water and Toxic Enforcement Act of 1986. Chemicals known to the State to cause cancer or reproductive toxicity.
  • Colborn T, D Dumanoski, JP Myers. 2006. Widespread Pollutants with Endocrine-disrupting Effects. Updated from original listing in "Our Stolen Future" (1996).
  • Illinois EPA (Illinois Environmental Protection Agency). 2000. Preliminary list of chemicals associated with endocrine system effects in animals and humans (*) or in vitro (+). In EPA (U.S. Environmental Protection Agency) 2000. Handbook for Non-Cancer Health Effects Valuation, Appendix C.
  • IARC (International Agency for Research on Cancer). 2008. Overall Evaluations of Carcinogenicity to Humans, as evaluated in IARC Monographs Volumes 1-99 (a total of 935 agents, mixtures and exposures).
  • EPA (U.S. Environmental Protection Agency). 2008. Integrated Risk Information System (IRIS). Evidence for human carcinogenicity based on 1986-2005 guidelines.
  • EU (European Union). 2000. Water Framework Directive (Directive 2000/60/EC ) - integrated river basin management for Europe. List of priority substances.
  • NLM (National Library of Medicine). 2012. PubMed online scientific bibliography data. http://www.pubmed.gov.

Understanding scores

Cosmetics and personal care products are not required to be tested for safety before being allowed on the market. The Skin Deep® scoring system was designed to help the public understand whether a product is safe to use or whether it contains ingredients of concern.

Every product and ingredient in Skin Deep gets a two-part score – one for hazard and one for data availability. The safest products score well by both measures, with a low hazard rating and a fair or better data availability rating.

HOW WE DETERMINE SCORES

Hazard score

The Skin Deep ingredient hazard score, from 1 to 10, reflects known and suspected hazards linked to the ingredients. The EWG VERIFIED® mark means a product meets EWG’s strictest criteria for transparency and health.

Score legend

Data availability

The Skin Deep data availability rating reflects the number of scientific studies about the product or ingredient in the published scientific literature.

NONE LIMITED FAIR GOOD ROBUST
Low Availability
Moderate Availability
High Availability

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