Detection of formaldehyde in textiles by chromotropic acid method

BACKGROUND: The common causes of textile dermatitis are formaldehyde resins and disperse dyes. There are various methods to detect the presence of formaldehyde in clothing.
AIM: To detect the presence of formaldehyde in various types of textiles by the chromotropic acid method and to assess the effect of washing on the formaldehyde content.
METHODS: Twenty randomly selected textiles from a local cloth store were tested for formaldehyde by the chromotropic acid method. A purple ring indicated a positive reaction. The intensity of the purple ring was graded from 1+ to 3+ and reassessed after washing the clothes.
RESULTS: Eleven out of the 20 textiles tested positive for formaldehyde. The fully synthetic clothes were free from formaldehyde. After the first and second washes the majority did not show a reduction in the formaldehyde content.
CONCLUSIONS: This is a simple and rapid test which can be used in the practical management of patients with textile allergy. Washing the clothes may not have an effect on the formaldehyde content.