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Data: Limited

Methylchloroisothiazolinone

IMAGE SOURCE: PubChem

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Other Concerns

Enhanced skin absorption, Use restrictions (high), Persistence and bioaccumulation (moderate), Ecotoxicology (low), and Irritation (skin, eyes, or lungs) (moderate)

SYNONYMS

● UNII-15O9QS218W COMPONENT DHNRXBZYEKSXIM-UHFFFAOYSA-N
● Q204121
● Q-9256
● 5-CHLORO-2-METHYL-4-ISOTHIAZOLIN-3-ONE (ACTIVE INGREDIENT >14%, CMI/MI 2.5 - 4.0)
● X5928
● 5-CHLORO-2-METHYL-2,3-DIHYDRO-1,2-THIAZOL-3-ONE
● DB-007017
● SR-01000944864
● W-107193
● SR-01000944864-1

Unacceptable

Unacceptable: EWG VERIFIED products cannot contain this ingredient

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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facial cleanser104 products
conditioner1127 products
liquid hand soap869 products
facial moisturizer/treatment10 products
shampoo1317 products
styling gel/lotion38 products
detangler12 products
bath oil/salts/soak64 products
body wash/cleanser975 products
exfoliant/scrub38 products
fragrance for men1 products
bubble bath154 products
moisturizer53 products
after sun product7 products
hair styling aid36 products
hair spray5 products
hand cream3 products
hair relaxer7 products
hair treatment/serum106 products
hair-loss treatment5 products
mask67 products
hair color and bleaching145 products
body firming lotion11 products
makeup remover3 products
eye liner3 products
Exfoliants2 products
mascara1 products
shaving cream10 products
hand sanitizer9 products
bar soap11 products
styling mousse/foam4 products
Hair Styling Gel3 products
Other Hair Care Preparations1 products
Facial Cleansing Water3 products
antiperspirant/deodorant4 products
baby wipes6 products
baby shampoo26 products
beard cleanser10 products
baby soap13 products
facial powder1 products
setting powder/spray1 products
Bath and Body Wipes2 products
beard care4 products
anti-aging1 products
foot cleansing1 products
baby bubble bath10 products
baby lotion3 products
baby oil8 products
damaged skin treatment1 products
muscle/joint soreness2 products
Oils & Serums1 products
Wipes3 products
bronzer/highlighter1 products
toners/astringents5 products
eyelash glue2 products
body spray1 products
lipstick1 products
Baby Bath Treatments, Tablets and Powders1 products
BB cream1 products
toothpaste1 products
foot odor control2 products
body powder1 products
sunless tanning1 products
serums & essences1 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)
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)
Human skin toxicant or allergen - strong evidenceCosmetic Ingredient Review (CIR)
Limited evidence of immune system toxicity or allergiesUS National Library of Medicine,

Cancer

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CONCERN REFERENCE
Mutagen - limited evidenceMutagenicity of cosmetic products containing Kathon(1996-01-01)

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 - Restricted in cosmetics; use, concentration, or manufacturing restrictions - Opinion on the mixture of 5-chloro-2-methylisothiazolin-3(2H)-one and 2-methylisothiazolin-3(2H)-one(2009-01-01)
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
Restricted in cosmetics (recommendations or requirements) - use, concentration, or manufacturing restrictions - Japan - prohibited for use in some types of cosmeticsJapan Ministry of Health
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 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
Persistent or bioaccumulative and moderate to high toxicity concern in humansOrganohalogen Pollutants and Human Health(2017-01-01)
  • Methylisothiazolinone contact allergy: a review(2011-12-01)
  • Six children with allergic contact dermatitis to methylisothiazolinone in wet wipes (baby wipes)(2014-02-01)
  • Cosmetic Ingredient Review (CIR)
  • US National Library of Medicine,
  • Mutagenicity of cosmetic products containing Kathon(1996-01-01)
  • Reregistration Eligibility Decision (RED) Methylisothiazolinone(1998-01-01)
  • Environment Canada
  • Health Hazard Evaluation Report, HEA 94 0402 2573(1996-01-01)
  • Opinion on the mixture of 5-chloro-2-methylisothiazolin-3(2H)-one and 2-methylisothiazolin-3(2H)-one(2009-01-01)
  • Health Canada
  • Japan Ministry of Health
  • Organohalogen Pollutants and Human Health(2017-01-01)

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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