Other ConcernsUse restrictions (high), Neurotoxicity (low), Ecotoxicology (low), and Irritation (skin, eyes, or lungs) (moderate)
SYNONYMS2-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, and METHYLISOTHIAZOLINONE
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.
See how this product scores for common concerns.
HIGHAllergies & Immunotoxicity
LOWDevelopmental and Reproductive Toxicity
- DATA SOURCES
Products with this Ingredient
|body wash/cleanser||382 products|
|liquid hand soap||357 products|
|hair color and bleaching||59 products|
|hair treatment/serum||57 products|
|bubble bath||54 products|
|facial cleanser||41 products|
|recreational sunscreen||19 products|
|hair styling aide||18 products|
|styling gel/lotion||16 products|
|bath oil/salts/soak||16 products|
|baby shampoo||15 products|
|facial moisturizer/treatment||14 products|
|baby wipes||10 products|
|baby bubble bath||10 products|
|daily use with SPF||9 products|
|beard cleanser||7 products|
|baby soap||6 products|
|serums & essences||5 products|
|hair spray||3 products|
|hand sanitizer||3 products|
|body firming lotion||2 products|
|after sun product||2 products|
|eye liner||2 products|
|shaving cream||2 products|
|nail polish||2 products|
|bar soap||2 products|
|baby oil||2 products|
|baby lotion||2 products|
|beard care||2 products|
|muscle/joint soreness||2 products|
|foot moisturizer||1 products|
|styling mousse/foam||1 products|
|around-eye cream||1 products|
|hair relaxer||1 products|
|sunless tanning||1 products|
|body spray||1 products|
|foot cleansing||1 products|
|baby sunscreen||1 products|
|after shave||1 products|
|eyelash glue||1 products|
|damaged skin treatment||1 products|
|Violation of government restrictions - Banned or found unsafe for use in cosmetics||Open scientific literature|
|Violation of government restrictions - Banned or found unsafe for use in cosmetics||Canada - Prohibited and Restricted Cosmetics Ingredients|
|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 cosmetics||Canada - Prohibited and Restricted Cosmetics Ingredients|
|Determined safe for use in cosmetics, subject to concentration or use limitations - Safe for use in cosmetics with some qualifications||Cosmetic Ingredient Review Assessments|
|Known human immune toxicant or allergen||Open scientific literature|
|Human sensitizer toxicant or allergen - strong evidence||Open scientific literature|
|Human skin toxicant or allergen - strong evidence||Cosmetic Ingredient Review Assessments|
|Human any toxicant or allergen - moderate evidence||Open scientific literature|
|One or more human case studies show significant skin or allergenic effects||Open scientific literature|
|Limited evidence of immune system toxicity or allergies||National Library of Medicine HazMap|
Irritation (skin, eyes, or lungs)
|Possible human skin sensitizer irritant||Open scientific literature|
|One or more in vitro tests on mammalian cells demonstrate neurotoxicity||Open scientific literature|
|Wildlife and environmental toxicity||Open scientific literature|
|Not suspected to be an environmental toxin||Environment Canada Domestic Substance List|
|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 product||Cosmetic Ingredient Review Assessments|
|331 studies in PubMed science library may include information on the toxicity of this chemical||NLM PubMed|
Persistence and bioaccumulation
|Not suspected to be bioaccumulative||Environment Canada Domestic Substance List|
|Not suspected to be persistent||Environment Canada Domestic Substance List|
Organ system toxicity (non-reproductive)
|Classified as not expected to be potentially toxic or harmful||Environment Canada Domestic Substance List|
- Open scientific/peer reviewed literature
- Health Canada. 2007. List of Prohibited and Restricted Cosmetic Ingredients. Canada's Cosmetic Ingredient Hotlist. March 2007.
- 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.
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
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.
The Skin Deep data availability rating reflects the number of scientific studies about the product or ingredient in the published scientific literature.