# Isothiazolinones in Disposable Rubber Gloves—Results of Chemical Analysis

## TL;DR

Disposable rubber gloves may contain isothiazolinones like BIT, which can cause contact allergies in frequent users.

## Contribution

Chemical analysis identified BIT and MI in disposable rubber gloves, linking them to potential contact allergy sources.

## Key findings

- BIT was found in 60% of analyzed gloves with concentrations up to 73.7 ppm.
- MI was detected in six nitrile gloves at low concentrations.
- Patients with isothiazolinone allergies often had multiple exposure sources.

## Abstract

Contact allergy to benzisothiazolinone (BIT) has increased in recent years, but exposure to it is not always found. It's important to know whether the gloves might be an isothiazolinone source especially in patients with symptoms from gloves and isothiazolinone contact allergy with or without allergy to rubber chemicals.

To present results of chemical analysis of isothiazolinones in disposable rubber gloves of patients in an occupational dermatology clinic.

We went through our chemical analysis record from 2018–2025 and identified isothiazolinone analyses done from disposable rubber gloves. The chemical analysis of glove extracts was done by liquid chromatography‐mass spectrometry (LC–MS). We screened the respective patients' files and collected information on their occupation, glove usage, patch test reactions as well as basic information on their hand eczema.

We discovered BIT in 30/54 (60%) analysed gloves (27 nitrile rubber gloves, 2 neoprene rubber gloves and 1 natural rubber glove) in concentrations of 0.3–73.7 ppm (mean 12.7 ppm, median 4.2 ppm). Methylisothiazolinone (MI) was found in solitary gloves in small concentrations. Isothiazolinone‐containing gloves were samples from altogether 21 patients, and six of them had several gloves that contained isothiazolinones. Many patients had also other isothiazolinone sources at work or at home.

Disposable rubber gloves are a possible BIT source. Several gloves contained BIT in a concentration that may be enough to induce contact allergy when gloves are used frequently.

Chemical analysis revealed benzisothiazolinone (BIT) in 30/54 disposable rubber gloves (27 nitrile rubber gloves, 2 neoprene rubber gloves and 1 natural rubber glove) in concentrations of 0.3–73.7 ppm. Methylisothiazolinone (MI) was found in six nitrile rubber gloves in small concentrations.