Also known as: Caswell No. 572A, EINECS 220-239-6, UNII-229D0E1QFA, MI, MIT
INCI: METHYLISOTHIAZOLINONE
METHYLISOTHIAZOLINONE (MIT) (CAS 2682-20-4) is a cosmetic preservative functioning as Preservative (broad-spectrum biocide). NOAEL 19 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: permitted; 5 safety opinions reviewed (cir). Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.
View industrial chemical safety profile for CAS 2682-20-4 →
METHYLISOTHIAZOLINONE (MIT) is classified GHS Danger (H301, H311, H302, H314, H317, H318, H330, H331) in the chemicals database but is allowed in EU cosmetics.
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Margin of Safety, dermal absorption, and sensitization profile summaries for METHYLISOTHIAZOLINONE (MIT).
Calculate MoS for your specific formulation with the MoS Calculator.
10 study endpoints found for METHYLISOTHIAZOLINONE (MIT). NOAEL (No Observed Adverse Effect Level) values are used to calculate the Margin of Safety per SCCS methodology.
| Endpoint | Value | Route | Species | Study Type | Source |
|---|---|---|---|---|---|
| NOAEL | =10 mg/kg/d | oral | rat | repeated dose toxicity | CIR_vision_codex |
| NOAEL | =10 mg/kg/d | oral | rat | repeated dose toxicity | CIR_vision_codex |
| NOAEL | =10 mg/kg/d | oral | rat | repeated dose toxicity | CIR_vision_codex |
| NOAEL | =10 mg/kg/d | oral | rat | repeated dose toxicity | CIR_vision_codex |
| NOAEL | =28.6 mg/kg bw/d | - | - | NOAEL study | CIR_vision_codex |
| NOAEL | =28.6 mg/kg bw/d | - | - | NOAEL study | CIR_vision_codex |
| NOAEL | =28.6 mg/kg bw/d | - | - | NOAEL study | CIR_vision_codex |
| NOAEL | =28.6 mg/kg bw/d | - | - | NOAEL study | CIR_vision_codex |
| NOAEL | =30 mg/kg/d | oral | rat | repeated dose toxicity | CIR_vision_codex |
| NOAEL | =30 mg/kg/d | oral | rat | repeated dose toxicity | CIR_vision_codex |
Official safety assessments from the Scientific Committee on Consumer Safety (SCCS) and Cosmetic Ingredient Review (CIR).
Pre-calculated NOAEL → SED → MoS audit trail for METHYLISOTHIAZOLINONE (MIT) across SCCS product categories, with measured dermal absorption where available.
Contact sensitization data for METHYLISOTHIAZOLINONE (MIT) based on clinical patch test studies and IFRA standards.
Source: NACDG 2021-22; ESSCA 2019/20
10 toxicity values from EPA ToxValDB (aggregated from CCTE, HPV, ToxRefDB, IRIS, and other regulatory dossiers).
| Endpoint | Value | Species | Route | Duration | Source |
|---|---|---|---|---|---|
| LC50 | =110 mg/m3 | Rat | inhalation | - | ECHA IUCLID |
| LC50 | =130 mg/m3 | Rat | inhalation | - | ECHA IUCLID |
| LC50 | =100 mg/m3 | Rat | inhalation | - | ECHA IUCLID |
| LC50 | =384 mg/m3 | Rat | inhalation | - | ECHA IUCLID |
| LC50 | =422 mg/m3 | Rat | inhalation | - | ECHA IUCLID |
| LC50 | =354 mg/m3 | Rat | inhalation | - | ECHA IUCLID |
| LD50 | >2000 mg/kg | Rat | dermal | acute | ECHA IUCLID |
| LD50 | =242 mg/kg | Rat | dermal | acute | ECHA IUCLID |
| LD50 | =285.5 mg/kg | Rat | oral | - | ECHA IUCLID |
| LD50 | =327.7 mg/kg | Rat | oral | - | ECHA IUCLID |
Legally binding harmonized classification per Regulation (EC) No 1272/2008 (CLP) Annex VI.
Inserted via ATP: ATP13
Adverse Outcome Pathway data across 5 assays (DPRA, KeratinoSens, hCLAT, LLNA, NESIL) aggregated from public sources.
Source: LLNA: Basketter et al (2001); DPRA: Gerberick et al. 2007 [DOI:10.1093/toxsci/kfm064] | Nukada et al. 2013 [DOI:10.1016/j.tiv.2012.11.006]; KS: Natsch et al. 2013 [DOI:10.1002/jat.2868]; hCLAT: Ashikaga et al. 2010 [DOI:10.1177/026119291003800403]
5 human repeat insult patch tests aggregated from dermatological literature.
| Test Type | N | Sensitized | Dose µg/cm² | NESIL µg/cm² | Potency |
|---|---|---|---|---|---|
| HRIPT | 97 | 0 | 100 | 100 | - |
| Clinical / epidemiol | - | 0 | - | - | strong |
| HRIPT | - | 0 | 100 | 100 | strong |
| HRIPT | - | 0 | - | - | - |
| HRIPT | - | 0 | 10 | - | - |
Cross-referenced EDC classifications, mechanism data, and dose-response evidence from EDLists, SIN List, and cosmetic-specific detail sources.
indirect modulator (immune/dermal)
| Endpoint | Target | Value | Direction |
|---|---|---|---|
| Thyroid hormone levels (T3/T4 ↓); tshβ upregulation | Thyroid axis (TR / TSH feedback) | EC50/IC50: LOEC = 30 µg/L (zebrafish whole-body T3/T4 decrease); LOEC: 30 µg/L (zebrafish); NOEC: not established mixed | thyroid disruptor |
| AR and ER receptor activity screening | AR / ERα | EC50/IC50: No significant ER/AR activity below cytotoxic threshold (~1 µM in many cell lines); LOEC: not established; NOEC: N/A mixed | not active in standard ER/AR screens at sub-cytotoxic concentrations |
| AhR transactivation | AhR | EC50/IC50: No AhR activity reported at sub-cytotoxic concentrations; LOEC: not established; NOEC: N/A mixed | not active in standard AhR assays below cytotoxic threshold |
| E2 and T production in H295R cells | Steroidogenesis | EC50/IC50: LOEC ≈ 0.1 µM for E2 increase (H295R, 48 h; preliminary); LOEC: ~0.1 µM; NOEC: not established mixed | active (E2 production ↑ at 0.1 µM LOEC in some studies) |
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
European Commission CosIng database Annex references per Regulation (EC) No 1223/2009.
Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.
| Jurisdiction | Status | Max % | Product Type |
|---|---|---|---|
| JP | restricted | Wash-away: 0.01% | Leave-on: 0.01% | Mucosa: Prohibited | Wash-away: 0.01% | Leave-on: 0.01% | Mucosa: Prohibited |
| CN | permitted_preservative | 0.0015 | Rinse-off products only |
| IN | permitted_preservative | 0.01 | rinse-off products (per IS 4707 2017) |
| AU | restricted | 0.0015 | rinse-off products |
| AU | restricted | 0.01 | rinse-off (historical) |
| GCC | restricted | 0.0015 | Rinse-off products only |
| SA | banned | - | Leave-on products |
| BR | permitted_preservative | 0.0015 | Rinse-off products only; prohibited in leave-on products; cannot be combined with MCI/MI mixture in same product |
Reported concentration ranges per product category from SCCS/CIR/industry sources.
| Product Category | Typical Range | Max Reported | Source |
|---|---|---|---|
| Shampoo | 0.0015 | 0.01 | CIR (2014 amended, cited PCPC 2014) |
7 property records from structured ingredient metadata.
Expert safety assessment and concern-level summary for METHYLISOTHIAZOLINONE (MIT).
Public NOAEL study rows linked to METHYLISOTHIAZOLINONE (MIT) by CAS number or substance name.
Units vary across source rows: mg/kg bw/day, mg/kg bw/d, mg/kg/d
Same-CAS public records found in pharmaceutical data.
Same-CAS rows from the pharmaceutical spoke database.
METHYLISOTHIAZOLINONE (MIT) has a safety rating of "GOOD" in our database. EU status: permitted. US status: restricted. 10 toxicological study endpoint(s) are available in our database. This ingredient has been reviewed by cir.
METHYLISOTHIAZOLINONE (MIT) EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
METHYLISOTHIAZOLINONE (MIT) functions as: Preservative (broad-spectrum biocide). It is classified as a Preservative in our database. CAS number: 2682-20-4.
The NOAEL (No Observed Adverse Effect Level) for METHYLISOTHIAZOLINONE (MIT) is =10 mg/kg/d based on a repeated dose toxicity study via oral route in rat. A total of 10 study endpoints are available. Source: CIR_vision_codex.
METHYLISOTHIAZOLINONE (MIT) also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
METHYLISOTHIAZOLINONE (MIT) is classified GHS Danger (H301, H311, H302, H314, H317, H318, H330, H331) in the chemicals database but is allowed in EU cosmetics.
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