Specimen No. 0198
AvoidSyntheticcosmetic preservative
Methylisothiazolinone
CAS 2682-20-4 · MIT · MI · Methylisothiazolinone
A synthetic preservative that became one of the most common contact allergens of the last decade, driving a documented epidemic of allergic contact dermatitis.
high confidence
Researched July 7, 2026Specimen 0198Methylisothiazolinone
Concerns
- Methylisothiazolinone drove a global epidemic of allergic contact dermatitis during 2010 to 2015, reaching its peak in 2013 and 2014 (Ozkaya 2020, PMID 32691417)
- It is a frequent contact allergen; after being regulated in the European Union a significant drop in cases was seen, whereas high rates continued in regions such as North America (Johansen 2022, PMID 35183605)
Regulatory flags
- ⚑IARC Class: NL
- ⚑EDC Status: Not established
- ⚑Regulatory: US: permitted, high sensitization rates persist; EU: restricted following the ACD epidemic
- ⚑Evidence Grade: A
Commonly found in
Rinse-off shampoo and conditionerWet wipesLiquid hand soapWater-based paint
Sources & references
Last researched: July 7, 2026
Research disclaimer: This rating is based on available peer-reviewed research and regulatory assessments at the time of publication. It is not medical advice. Consult a qualified professional for personal health or skin concerns.
Check another ingredient
Search our database of scored cosmetic, food, and household ingredients — or scan a full product label.
Open the Ingredient Lab