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Data: Good

Hydroquinone

IMAGE SOURCE: PubChem

SEARCH PRODUCTS

Other Concerns

Use restrictions (high), Non-reproductive organ system toxicity (high), and Ecotoxicology (low)

SYNONYMS

● 1,4-BENZENEDIOL
● 1,4-DIHYDROXYBENZENE
● 1,4BENZENEDIOL
● 4-HYDROXYPHENOL
● HYDROQUINONE
● P-DIOXYBENZENE
● P-HYDROXYPHENOL

Unacceptable

Unacceptable: EWG VERIFIED products cannot contain this ingredient


Hydroquinone is an aromatic organic compound. In the United States, Hydroquinone may be used as an active ingredient in OTC drug products. When used as an active drug ingredient, the established name is Hydroquinone.

Common concerns

See how this product scores for common concerns.

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

Ingredient concerns

  • CONCERNS
  • DATA SOURCES

Products with this Ingredient

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facial moisturizer/treatment3 products

Organ system toxicity (non-reproductive)

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CONCERN REFERENCE
Known human respiratory toxicantEPA Hazardous Air Pollutants
Classified as a high human health priorityEnvironment Canada Domestic Substance List
Classified as expected to be toxic or harmfulEnvironment Canada Domestic Substance List
One or more animal studies show classified as toxic effects at low dosesEPA Categorized List of Inert Pesticide Ingredients
Limited evidence of cardiovascular or blood toxicityNational Library of Medicine HazMap
Limited evidence of sense organ toxicityScorecard.org Toxicity Information
One or more animal studies show classified as toxic effects at moderate doses (low dose studies may be unavailable for this ingredient)EPA Toxic Release Inventory PBTs

Use restrictions

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CONCERN REFERENCE
Violation of government restrictions - Banned or found unsafe for use in cosmeticsCosIng
Violation of industry recommendations - Restricted in cosmetics; use, concentration, or manufacturing restrictions - Safe for brief discontinuous use followed by thorough rinsingCosmetic Ingredient Review Assessments
Restricted in cosmetics (recommendations or requirements) - use, concentration, or manufacturing restrictions - Use is restricted in Canadian cosmeticsCanada - Prohibited and Restricted Cosmetics Ingredients
Determined safe for use in cosmetics, subject to concentration or use limitations - anyCTFA International Cosmetic Ingredient Dictionary and Handbook
Determined safe for use in cosmetics, subject to concentration or use limitations - Safe for use in cosmetics with some qualificationsCosmetic Ingredient Review Assessments

Allergies/immunotoxicity

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CONCERN REFERENCE
Human skin toxicant or allergen - strong evidenceEWG Assessment of Open Scientific Literature
Human skin toxicant or allergen - strong evidenceCosmetic Ingredient Review Assessments
Limited evidence of immune system toxicity or allergiesScorecard.org Toxicity Information
Limited evidence of immune system toxicity or allergiesNational Library of Medicine HazMap

Cancer

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CONCERN REFERENCE
Limited evidence of carcinogenicityAmer Conf of Gov't Industrial Hygienists - Carcinogens
Limited evidence of carcinogenicityCPS&Q - Classification & Labelling
Cancer - limited evidenceScorecard.org Toxicity Information
Cancer - limited evidenceCTFA International Cosmetic Ingredient Dictionary and Handbook
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

Developmental/reproductive toxicity

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CONCERN REFERENCE
Limited evidence of reproductive toxicityScorecard.org Toxicity Information

Ecotoxicology

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CONCERN REFERENCE
Wildlife and environmental toxicityCPS&Q - Classification & Labelling
Suspected to be an environmental toxinEnvironment Canada Domestic Substance List

Data gaps

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CONCERN REFERENCE
Risk assessment method deficiencies and data gaps - Maximum reported "as used" concentration is basis of safety assessment by industry safety panel (Cosmetic Ingredient Review, CIR) - implicit safe concentration limit in productCosmetic Ingredient Review Assessments
6109 studies in PubMed science library may include information on the toxicity of this chemicalNLM PubMed

Persistence and bioaccumulation

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CONCERN REFERENCE
Not suspected to be bioaccumulativeEnvironment Canada Domestic Substance List
Not suspected to be persistentEnvironment Canada Domestic Substance List

Informational

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CONCERN REFERENCE
Industry or government recommendations for safe use: restrictions on concentration, impurities, product types, or manufacturing methods - Safe for brief discontinuous use followed by thorough rinsingCosmetic Ingredient Review Assessments
  • 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.
  • EPA (U.S. Environmental Protection Agency). 1987 & 2005. Office of Pesticide Programs. Inert (other) Pesticide Ingredients in Pesticide Products - Categorized List of Inert (other) Pesticide Ingredients.
  • 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.
  • European Commission. 2013. Cosing, the European Commission database with information on cosmetic substances and ingredients. Accessed on March 1, 2013 at http://ec.europa.eu/consumers/cosmetics/cosing/ .
  • CIR (Cosmetic Ingredient Review). 2006. CIR Compendium, containing abstracts, discussions, and conclusions of CIR cosmetic ingredient safety assessments. Washington DC.
  • Health Canada. 2007. List of Prohibited and Restricted Cosmetic Ingredients. Canada's Cosmetic Ingredient Hotlist. March 2007.
  • CTFA (Cosmetic, Toiletry and Fragrance Association). 2006. International Cosmetic Ingredient Dictionary and Handbook, 11th Edition. Color Additive Information. Washington, DC.
  • EWG Assessment of Open Scientific Literature
  • ACGIH (American Conference of Governmental Industrial Hygienists) 2008. ACGIH cancer classification system. www.acgih.org.
  • 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.
  • 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).
  • 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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