Development of a Generic Analysis Method for Isothiazolinones in Consumer Products Prompted by Increased Sensitisation to Benzisothiazolinone
(2026) In Contact Dermatitis- Abstract
Background: Isothiazolinones are widely used as preservatives in both cosmetic and non-cosmetic products. Sensitisation to isothiazolinones other than chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT), present in the baseline series, is increasing. Objectives: To investigate the prevalence of sensitisation to benzisothiazolinone (BIT) in comparison to CMIT/MIT and to develop a product-independent analysis method of isothiazolinones for laboratories with basic instrumentation. Patients and Methods: Patch testing with BIT and CMIT/MIT was performed in 803 consecutively tested dermatitis patients. A simple and general analysis method for isothiazolinones was developed for HPLC-UV. Results: Investigation of 14 products labelled... (More)
Background: Isothiazolinones are widely used as preservatives in both cosmetic and non-cosmetic products. Sensitisation to isothiazolinones other than chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT), present in the baseline series, is increasing. Objectives: To investigate the prevalence of sensitisation to benzisothiazolinone (BIT) in comparison to CMIT/MIT and to develop a product-independent analysis method of isothiazolinones for laboratories with basic instrumentation. Patients and Methods: Patch testing with BIT and CMIT/MIT was performed in 803 consecutively tested dermatitis patients. A simple and general analysis method for isothiazolinones was developed for HPLC-UV. Results: Investigation of 14 products labelled to contain BIT and/or CMIT/MIT (cosmetic and non-cosmetic) showed concentrations of BIT in non-cosmetic products of up to 272 ppm. Maximum detected concentrations of CMIT and MIT were 0.3 and 1.5 ppm, respectively. Dichloroctylisothiazolinone and MIT were detected in an unlabelled hobby paint. BIT was a significantly more common cause of sensitisation than CMIT/MIT, at 7.7% and 5.2%, respectively. Conclusions: Results confirm previous reports indicating that sensitisation to BIT is increasing in dermatitis patients in western Sweden. Analysis of products showed that concentrations of BIT can be several orders of magnitude higher than those of CMIT/MIT in products to which skin contact can be frequent and long lasting.
(Less)
- author
- Farbrot, Anne ; Kentson, Jakob ; Akdeve, Hatice Koca ; Blom, Anders ; Ehn, Britt Marie ; Babic Mulic, Naida ; Amirbeagi, Firoozeh ; Alsterholm, Mikael and Hagvall, Lina LU
- organization
- publishing date
- 2026
- type
- Contribution to journal
- publication status
- in press
- subject
- keywords
- benzisothiazolinone, contact allergy, HPLC, isothiazolinones, patch testing, preservatives
- in
- Contact Dermatitis
- publisher
- Wiley-Blackwell
- external identifiers
-
- pmid:41889151
- scopus:105034092064
- ISSN
- 0105-1873
- DOI
- 10.1111/cod.70147
- language
- English
- LU publication?
- yes
- id
- 4062026c-d988-41c8-8548-439cbaed5d89
- date added to LUP
- 2026-05-21 15:43:11
- date last changed
- 2026-06-04 16:40:21
@article{4062026c-d988-41c8-8548-439cbaed5d89,
abstract = {{<p>Background: Isothiazolinones are widely used as preservatives in both cosmetic and non-cosmetic products. Sensitisation to isothiazolinones other than chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT), present in the baseline series, is increasing. Objectives: To investigate the prevalence of sensitisation to benzisothiazolinone (BIT) in comparison to CMIT/MIT and to develop a product-independent analysis method of isothiazolinones for laboratories with basic instrumentation. Patients and Methods: Patch testing with BIT and CMIT/MIT was performed in 803 consecutively tested dermatitis patients. A simple and general analysis method for isothiazolinones was developed for HPLC-UV. Results: Investigation of 14 products labelled to contain BIT and/or CMIT/MIT (cosmetic and non-cosmetic) showed concentrations of BIT in non-cosmetic products of up to 272 ppm. Maximum detected concentrations of CMIT and MIT were 0.3 and 1.5 ppm, respectively. Dichloroctylisothiazolinone and MIT were detected in an unlabelled hobby paint. BIT was a significantly more common cause of sensitisation than CMIT/MIT, at 7.7% and 5.2%, respectively. Conclusions: Results confirm previous reports indicating that sensitisation to BIT is increasing in dermatitis patients in western Sweden. Analysis of products showed that concentrations of BIT can be several orders of magnitude higher than those of CMIT/MIT in products to which skin contact can be frequent and long lasting.</p>}},
author = {{Farbrot, Anne and Kentson, Jakob and Akdeve, Hatice Koca and Blom, Anders and Ehn, Britt Marie and Babic Mulic, Naida and Amirbeagi, Firoozeh and Alsterholm, Mikael and Hagvall, Lina}},
issn = {{0105-1873}},
keywords = {{benzisothiazolinone; contact allergy; HPLC; isothiazolinones; patch testing; preservatives}},
language = {{eng}},
publisher = {{Wiley-Blackwell}},
series = {{Contact Dermatitis}},
title = {{Development of a Generic Analysis Method for Isothiazolinones in Consumer Products Prompted by Increased Sensitisation to Benzisothiazolinone}},
url = {{http://dx.doi.org/10.1111/cod.70147}},
doi = {{10.1111/cod.70147}},
year = {{2026}},
}