EWG Skin Deep® | What is CYSTEINE

HOW WE DETERMINE SCORES Learn more About EWG VERIFIED®

Data: Fair

Cysteine

IMAGE SOURCE: PubChem

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Other Concerns

SYNONYMS

● CYSTEINE

● CYSTEINE, DL-

● DL- CYSTEINE

● L-CYSTEINE

Restricted

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

Cysteine is an amino acid.

Common concerns

See how this product scores for common concerns.

LOW

Cancer
LOW

Allergies & Immunotoxicity
LOW

Developmental and Reproductive Toxicity
LOW

Use Restrictions

Ingredient concerns

CONCERNS
DATA SOURCES

Products with this Ingredient

conditioner	8 products
mask	6 products
shampoo	4 products
facial moisturizer/treatment	3 products
baby wipes	2 products
styling gel/lotion	2 products
hair treatment/serum	2 products
serums & essences	2 products
facial cleanser	1 products
hand cream	1 products
foot cleansing	1 products
around-eye cream	1 products
hair styling aide	1 products

Multiple, additive exposure sources

CONCERN	REFERENCE
Designated as safe for general or specific, limited use in food	FDA Everything Added to Food
Designated as safe for general or specific, limited use in food	FDA Food Additive Status

Ecotoxicology

CONCERN	REFERENCE
Not suspected to be an environmental toxin	Environment Canada Domestic Substance List

Organ system toxicity (non-reproductive)

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

Persistence and bioaccumulation

CONCERN	REFERENCE
Not suspected to be persistent	Environment Canada Domestic Substance List
Not suspected to be bioaccumulative	Environment Canada Domestic Substance List

Informational

CONCERN	REFERENCE
Industry or government recommendations for safe use: restrictions on concentration, impurities, product types, or manufacturing methods - any	Open scientific literature

Data gaps

CONCERN	REFERENCE
94408 studies in PubMed science library may include information on the toxicity of this chemical	NLM PubMed

FDA (U.S. Food and Drug Administration). 2008. EAFUS [Everything Added to Food]: A Food Additive Database. FDA Office of Food Safety and Applied Nutrition.
FDA (U.S. Food and Drug Administration) 2006. Food Additive Status List. Downloaded from http://www.cfsan.fda.gov/%7Edms/opa-appa.html, Oct 16, 2006.
EC (Environment Canada). 2008. Domestic Substances List Categorization. Canadian Environmental Protection Act (CEPA) Environmental Registry.
Open scientific/peer reviewed literature
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.

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