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Data: Good

Methylisothiazolinone

IMAGE SOURCE: PubChem

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Other Concerns

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

SYNONYMS

● DB-005250
● FT-0601044
● X5929
● Q423870
● 2-METHYL-4-ISOTHIAZOLIN-3-ONE, ANALYTICAL STANDARD
● AB0011560
● 682M204
● CAS-2682-20-4
● SC-16032
● K-6885

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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after shave2 products
after sun product8 products
anti-aging11 products
antiperspirant/deodorant7 products
around-eye cream2 products
Baby Bath Treatments, Tablets and Powders1 products
baby bubble bath10 products
baby lotion3 products
baby oil8 products
baby shampoo30 products
baby soap13 products
baby sunscreen1 products
baby wipes10 products
bar soap12 products
Bath and Body Wipes2 products
bath oil/salts/soak64 products
BB cream2 products
recreational sunscreen12 products
beard care4 products
beard cleanser10 products
blush6 products
body firming lotion16 products
body powder1 products
body spray6 products
body wash/cleanser1028 products
bronzer/highlighter10 products
bubble bath159 products
concealer1 products
conditioner1111 products
damaged skin treatment2 products
detangler17 products
exfoliant/scrub76 products
Exfoliants4 products
eye liner6 products
eye makeup remover1 products
eye shadow3 products
eyelash glue1 products
facial cleanser143 products
Facial Cleansing Water3 products
facial moisturizer/treatment35 products
facial powder2 products
foot cleansing6 products
foot moisturizer4 products
foot odor control2 products
foundation10 products
fragrance for men1 products
glitter5 products
hair color and bleaching146 products
hair relaxer9 products
hair spray12 products
hair styling aid87 products
Hair Styling Gel5 products
hair treatment/serum144 products
hair-loss treatment6 products
hand cream8 products
hand sanitizer14 products
lipstick1 products
liquid hand soap902 products
makeup remover5 products
mascara13 products
mask81 products
moisturizer85 products
daily use with SPF7 products
muscle/joint soreness2 products
nail polish2 products
nail treatment1 products
Oils & Serums1 products
Other Hair Care Preparations2 products
Putties, Puddings & Clays1 products
serums & essences8 products
setting powder/spray1 products
shampoo1326 products
shaving cream16 products
shaving cream (men's)6 products
styling gel/lotion83 products
styling mousse/foam11 products
sunless tanning2 products
toners/astringents9 products
toothpaste2 products
Under Eye Concealers1 products
Wipes3 products

Allergies/immunotoxicity

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CONCERN REFERENCE
Human skin toxicant or allergen - moderate evidenceMethylisothiazolinone contact allergy: a review(2011-12-01)
Human toxicant or allergen - moderate evidenceMethylisothiazolinone contact allergy: a review(2011-12-01)
Human sensitizer toxicant or allergen - strong evidenceFinal report of the safety assessment of methylisothiazolinone(2010-07-01)
One or more human case studies show significant skin or allergenic effectsSix children with allergic contact dermatitis to methylisothiazolinone in wet wipes (baby wipes)(2014-02-01)
Known human immune toxicant or allergenOpinion on Methylisothiazolinone (P94) Submission II (Sensitisation only)(2014-01-01)
Human skin toxicant or allergen - strong evidenceCosmetic Ingredient Review (CIR)
Limited evidence of immune system toxicity or allergiesUS. National Library of Medicine,

Neurotoxicity

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CONCERN REFERENCE
One or more in vitro tests on mammalian cells demonstrate neurotoxicityIn vitro neurotoxicity of methylisothiazolinone, a commonly used industrial and household biocide, proceeds via a zinc and extracellular signal-regulated kinase mitogen-activated protein kinase-dependent pathway(2002-09-01)

Ecotoxicology

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CONCERN REFERENCE
Wildlife and environmental toxicityReregistration Eligibility Decision (RED) Methylisothiazolinone(1998-01-01)
Not suspected to be an environmental toxinEnvironment Canada

Irritation (skin, eyes, or lungs)

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CONCERN REFERENCE
Possible human skin sensitizer irritantHealth Hazard Evaluation Report, HEA 94 0402 2573(1996-01-01)

Use restrictions

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CONCERN REFERENCE
Violation of government restrictions - Banned or found unsafe for use in cosmeticsOpinion on Methylisothiazolinone (P94) Submission II (Sensitisation only)(2014-01-01)
Violation of government restrictions - Banned or found unsafe for use in cosmeticsMethylisothiazolinone (MI) contained in cosmetics may cause allergies BfR opinion Nr(2013-01-01)
Restricted in cosmetics (recommendations or requirements) - use, concentration, or manufacturing restrictions - Use is restricted in Canadian cosmeticsHealth Canada
Determined safe for use in cosmetics, subject to concentration or use limitations - Safe for use in cosmetics with some qualificationsCosmetic Ingredient Review (CIR)
Determined safe for use in cosmetics, subject to concentration or use limitations - Distinction between safe conc in leave-on and rinse-offCosmetic Ingredient Review (CIR)
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 Ministry of Health
Violation of government restrictions - Banned or found unsafe for use in cosmeticsHealth Canada

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 (CIR)

Organ system toxicity (non-reproductive)

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

Persistence and bioaccumulation

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CONCERN REFERENCE
Not suspected to be persistentEnvironment Canada
Not suspected to be bioaccumulativeEnvironment Canada
  • Methylisothiazolinone contact allergy: a review(2011-12-01)
  • Final report of the safety assessment of methylisothiazolinone(2010-07-01)
  • Six children with allergic contact dermatitis to methylisothiazolinone in wet wipes (baby wipes)(2014-02-01)
  • Opinion on Methylisothiazolinone (P94) Submission II (Sensitisation only)(2014-01-01)
  • Cosmetic Ingredient Review (CIR)
  • US. National Library of Medicine,
  • In vitro neurotoxicity of methylisothiazolinone, a commonly used industrial and household biocide, proceeds via a zinc and extracellular signal-regulated kinase mitogen-activated protein kinase-dependent pathway(2002-09-01)
  • Reregistration Eligibility Decision (RED) Methylisothiazolinone(1998-01-01)
  • Environment Canada
  • Health Hazard Evaluation Report, HEA 94 0402 2573(1996-01-01)
  • Methylisothiazolinone (MI) contained in cosmetics may cause allergies BfR opinion Nr(2013-01-01)
  • Health Canada
  • Japan Ministry of Health

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
WEIGHT-OF-EVIDENCE APPROACH

A product’s hazard score is not an average of the ingredients’ hazard scores. It is calculated using a weight-of-evidence approach that factors in all of the hazards or health impacts associated with the ingredients.

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
NONE

Ingredients have not been assessed.

LIMITED-FAIR

There is only a modest volume of research.

GOOD-ROBUST

Ingredients have been studied extensively.

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