Biochemical parameters of liver function in artisans occupationally exposed to "vat dyes"

Vat dyes are the class of dyes used in textile dyeing in Abeokuta, South Western Nigeria. While some dyes (including vat dyes intermediates) have been associated with adverse effects on manufacturer's health, there is paucity of data on effects of occupational exposure to vat dyes among end users, such as those involved in textile dyeing and finishing.

To investigate the possible effect of occupational exposure to vat dyes on the functions of the liver.

Using convenience sampling technique, a cohort of dye workers (n=117) with a minimum of one year and a maximum of 60 years duration of exposure (mean =17.03 ± 1.19 years) were recruited in this study. Sixty traders, matched for age and sex and who had no previous exposure to vat dyes were selected as controls. A structured questionnaire was used to obtain information on demographic, occupational and environmental characteristics of the subjects. Plasma activities of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and plasma concentrations of total protein, albumin and total bilirubin were measured using standard spectrophotometric methods.

SPSS version 11.0 was used for statistical analyses. Tests of significance were carried out using Student's t test, and correlation co-efficient.

The activity of ALP and the concentrations of total protein and albumin were significantly lower (P <0.05) in the exposed group. ALT and AST activities were significantly higher (P <0.05) in the exposed group. Occupational exposure to vat dyes may result in sub-clinical adverse effects on the liver, involving inhibition of its synthetic function.