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Data: Fair

Methylchloroisothiazolinone

IMAGE SOURCE: PubChem

SEARCH PRODUCTS

Other Concerns

Use restrictions (high), Ecotoxicology (low), and Irritation (skin, eyes, or lungs) (moderate)

SYNONYMS

3(2H)ISOTHIAZOLONE, 5CHLORO2METHYL, 4-ISOTHIAZOLIN-3-ONE, 5-CHLORO-2-METHYL-, 5-CHLORO-2-METHYL- 4-ISOTHIAZOLIN-3-ONE, 5-CHLORO-2-METHYL-2H-ISOTHIAZOL-3-ONE, 5-CHLORO-2-METHYL-4-ISOTHIAZOLIN-3-ONE, METHYLCHLOROISOTHIAZOLINONE, and METHYLCHLOROTHIAZOLINONE

Restricted

Restricted: EWG VERIFIED products cannot contain this ingredient without adequate substantiation


Methylchloroisothiazolinone is a widely-used preservative; has been associated with allergic reactions.

Common concerns

See how this product scores for common concerns.

  • LOW
    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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shampoo445 products
conditioner429 products
body wash/cleanser379 products
liquid hand soap368 products
hair color and bleaching60 products
bubble bath55 products
hair treatment/serum47 products
facial cleanser46 products
baby shampoo14 products
bath oil/salts/soak14 products
exfoliant/scrub12 products
baby bubble bath10 products
hair styling aide10 products
mask9 products
styling gel/lotion9 products
baby wipes8 products
moisturizer8 products
baby soap7 products
beard cleanser6 products
bar soap3 products
toners/astringents3 products
hand sanitizer3 products
3 products
baby oil2 products
hair spray2 products
muscle/joint soreness2 products
eyelash glue2 products
baby lotion2 products
shaving cream2 products
after sun product2 products
beard care2 products
hair relaxer1 products
damaged skin treatment1 products
eye liner1 products
body spray1 products
foot cleansing1 products
anti-aging1 products
sunless tanning1 products
styling mousse/foam1 products
detangler1 products
body firming lotion1 products

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
Violation of government restrictions - Restricted in cosmetics; use, concentration, or manufacturing restrictions - anyOpen scientific literature
Restricted in cosmetics (recommendations or requirements) - use, concentration, or manufacturing restrictions - Japan - prohibited for use in some types of cosmetics when combined with certain other ingredientsJapan's Standards for Cosmetics
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 - Safe for use in cosmetics with some qualificationsCosmetic Ingredient Review Assessments

Irritation (skin, eyes, or lungs)

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CONCERN REFERENCE
Possible human skin irritantOpen scientific literature

Allergies/immunotoxicity

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CONCERN REFERENCE
Human skin toxicant or allergen - strong evidenceCosmetic Ingredient Review Assessments
Human skin toxicant or allergen - moderate evidenceOpen scientific literature
One or more human case studies show significant skin or allergenic effectsOpen scientific literature
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
Mutagen - limited evidenceOpen scientific literature

Ecotoxicology

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CONCERN REFERENCE
Wildlife and environmental toxicityOpen scientific literature
Not 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
232 studies in PubMed science library may include information on the toxicity of this chemicalNLM PubMed

Organ system toxicity (non-reproductive)

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CONCERN REFERENCE
Classified as not expected to be potentially toxic or harmfulEnvironment Canada Domestic Substance List

Persistence and bioaccumulation

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CONCERN REFERENCE
Not suspected to be persistentEnvironment Canada Domestic Substance List
Not suspected to be bioaccumulativeEnvironment Canada Domestic Substance List
  • Health Canada. 2007. List of Prohibited and Restricted Cosmetic Ingredients. Canada's Cosmetic Ingredient Hotlist. March 2007.
  • Open scientific/peer reviewed literature
  • Japan Ministry of Health, Labour and Welfare. 2006. Standards for Cosmetics. Evaluation and Licensing Division. Pharmaceutical and Food Safety Bureau.
  • CIR (Cosmetic Ingredient Review). 2006. CIR Compendium, containing abstracts, discussions, and conclusions of CIR cosmetic ingredient safety assessments. Washington DC.
  • ED (Environmental Defense). 2006. Scorecard _ The Pollution Information Site. http://www.scorecard.org.
  • NLM (National Library of Medicine). 2006. HazMap — Occupational Exposure to Hazardous Agents.
  • EC (Environment Canada). 2008. Domestic Substances List Categorization. Canadian Environmental Protection Act (CEPA) Environmental Registry.
  • 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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