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Data: Fair

Methylisothiazolinone

IMAGE SOURCE: PubChem

SEARCH PRODUCTS

Other Concerns

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

SYNONYMS

● 2-METHYL- 3(2H)-ISOTHIAZOLONE
● 2-METHYL-2H-ISOTHIAZOL-3-ONE
● 2-METHYL-3(2H)-ISOTHIAZOLONE
● 2-METHYL-4-ISOTHIAZOLIN-3-ONE
● 3(2H)-ISOTHIAZOLONE, 2-METHYL-
● 3(2H)ISOTHIAZOLONE, 2METHYL
● METHYLCHLOROISOTHIAZOLINONE225METHYLISOTHIAZOLINONE SOLUTION
● METHYLISOTHIAZOLINONE

Unacceptable

Unacceptable: EWG VERIFIED products cannot contain this ingredient


Methylisothiazolinone is a widely-used preservative; has been associated with allergic reactions. Lab studies on the brain cells of mammals also suggest that methylisothiazolinone may be neurotoxic.

Common concerns

See how this product scores for common concerns.

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

Ingredient concerns

  • CONCERNS
  • DATA SOURCES

Products with this Ingredient

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shampoo552 products
conditioner440 products
liquid hand soap375 products
body wash/cleanser334 products
moisturizer49 products
bubble bath46 products
hair treatment/serum44 products
hair color and bleaching40 products
facial cleanser36 products
bath oil/salts/soak26 products
styling gel/lotion20 products
exfoliant/scrub18 products
facial moisturizer/treatment17 products
hair styling aide17 products
recreational sunscreen16 products
mask16 products
baby shampoo13 products
baby wipes12 products
beard cleanser8 products
daily use with SPF7 products
baby soap7 products
baby bubble bath6 products
body cleansing wipes6 products
shaving cream5 products
serums & essences5 products
styling mousse/foam4 products
toners/astringents4 products
hand sanitizer3 products
3 products
baby oil3 products
anti-aging2 products
hand cream2 products
hair spray2 products
detangler2 products
body firming lotion2 products
eye liner2 products
foot odor control2 products
baby lotion2 products
beard care2 products
antiperspirant/deodorant1 products
mascara1 products
concealer1 products
after sun product1 products
hair relaxer1 products
bronzer/highlighter1 products
blush1 products
foundation1 products
depilatory1 products
makeup remover1 products
BB cream1 products
nail polish1 products
body spray1 products
bar soap1 products
baby sunscreen1 products
lipstick1 products
after shave1 products
eyelash glue1 products
muscle/joint soreness1 products
nail glue1 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 - Banned or found unsafe for use in cosmeticsOpen scientific literature
Restricted in cosmetics (recommendations or requirements) - use, concentration, or manufacturing restrictions - Japan - concentration limit in some types of cosmetics when combined with certain other ingredient(s)Japan'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

Allergies/immunotoxicity

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CONCERN REFERENCE
Known human immune toxicant or allergenOpen scientific literature
Human skin toxicant or allergen - strong evidenceCosmetic Ingredient Review Assessments
Human sensitizer toxicant or allergen - strong evidenceOpen scientific literature
Human any 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 allergiesNational Library of Medicine HazMap

Irritation (skin, eyes, or lungs)

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CONCERN REFERENCE
Possible human skin sensitizer irritantOpen scientific literature

Neurotoxicity

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CONCERN REFERENCE
One or more in vitro tests on mammalian cells demonstrate neurotoxicityOpen 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
331 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

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
  • 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.
  • 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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