Chloromethylisothiazolones

Synonym(s)

5-chloro-2-methyl-3(2H)-isothiazolones; (Chlorine)methylisothiazolones

Evaluation of (chlorine)methylisothiazolone with regard to the effect of an allergy on the reduction of earning capacity:

The individual substances 5-chloro-2-methyl-4-isothiazolone (MCI) and 2-methyl-4-isothiazolone (MI) are normally present as a mixture in the ratio 3:1 in commercially available products. MCI/MI is a biocide with bactericidal and fungicidal activity. The application concentrations are between 5 ppm (paper production) and 30 ppm (aqueous inks).
Relevant occupational exposures: Occupational groups concerned are painters, varnishers, metalworkers and metalworking trades. It can be assumed that companies will re-preserve working fluids (e.g. cooling lubricants) on their own in order to extend their shelf life. Sensitization of employees after accidental skin contact with high MCI/MI stock solutions has been published.
Effect of allergy: "low" to "moderate", in justified individual cases "severe". The following professions are currently closed due to the frequent use of MCI/MI: painters, varnishers, metalworkers and metalworking professions where there is contact with MCI/MI (e.g. in water-mixed cooling lubricants), and professions in the printing industry. In the case of a very high degree of sensitisation to aerogenic contact dermatitis, a number of other professions may be closed (construction, electricians, interior decorators) and cause a "serious" effect.

Diepgen TL et al. (2005) Evidence-based assessment of the effect of type IV allergies in the reduction of earning capacity - assessment of occupational skin diseases. Dermatologist 56: 207-223
Pardo A et al (2007) The effect of physical and chemical properties of swimming pool water and its close environment on the development of contact dermatitis in hydrotherapists. Am J Ind Med 50: 122-126