Hepatic Functions of Persons Occupationally Exposed To Formaldehyde in Calabar, Nigeria

Abstract

Dependence on formaldehyde as a biological preservative has remained a common practice in most developing countries, particularly in Nigeria where regulation and enforcement of labour guidelines are at its lowest ebb compared to developed populations. This research was carried out to investigate hepatic functions in persons occupationally exposed to formaldehyde in Calabar metropolis. Eighty eight male and female subjects comprising anatomists, medical laboratory attendants, medical laboratory scientists and morticians occupationally exposed to formaldehyde in this locality were enrolled in the study. Another group of eighty eight age and sex-matched individuals without formaldehyde exposure served as control subjects. Participants were between 24-52 years of age. Informed consent was obtained from all enrolled subjects. A structured questionnaire was utilized to capture the bio-data and other pertinent information on work place exposure. Hepatic function was assessed by measuring; Aspartate Transaminase (AST), Alanine Transaminase (ALT), Bilirubin, Total Protein (TP), Albumin and Alpha-Fetoprotein (AFP). These were assayed by colourimetric methods with the exception of AFP that was measured using enzyme-linked immunosorbent assay. While AFP and ALT were significantly increased (p<0.05), TP and Albumin were significantly reduced (p<0.05) in persons occupationally exposed to formaldehyde compared to control subjects. Furthermore, morticians (embalmers) had significantly (p<0.05) increased levels of AFP and Bilirubin but lower TP and Albumin levels compared to medical laboratory staff. Moreover, AFP correlated negatively with TP and Albumin (r = -0.476 and -0.602 and respectively). Findings from this study point towards possible formaldehyde toxicity among exposed persons particularly embalmers.

Keywords: Formaldehyde, exposure, toxicity