Benzisothiazolinone (BIT)CAS 2634-33-5
The "MIT-free" replacement that's still an isothiazolinone — different sensitization profile, same chemistry family.
Toxic Chemical Databases
Substance-specific listings — these flags are for Benzisothiazolinone alone, not for the broader family.
Chemical Type
Isothiazolinone Preservative
Chemical Description
BIT is a structural variant of MIT — benzene-fused ring instead of methyl. It shares the same biocidal mechanism and the same risk of skin sensitization, but the cross-reactivity profile is different: a person sensitized to MIT may or may not react to BIT, and vice versa. Manufacturers reformulated to BIT after MIT restrictions and labeled products "MIT-free" — true on the label, but BIT-sensitized patients are now appearing in dermatology clinics at rising rates. EU REACH SVHC listed BIT as a skin sensitizer in 2020.
Biological Activity
Severity scores specific to this substance, NOT the parent family average. Differences between siblings are real and meaningful.
Top Health Consequences
- Skin sensitization (separate from MIT cross-reactivity)
- REACH SVHC Candidate List entry for sensitization
- "MIT-free" claims often still contain BIT
- Allergic contact dermatitis with chronic exposure
Pathways of Exposure
- Inhalation during latex paint application
- Dermal contact with treated water-based products
- House dust from treated wallpaper and adhesives
Building Materials with Benzisothiazolinone
Listed alphabetically — product categories where this specific substance appears.
Latex Paint Preservation ("MIT-Free" Lines)
Leather Treatment Preservation
Sealant & Caulk Preservation
Water-Based Construction Adhesives