Preliminary Investigation into Urinary 1-Hydroxypyrene as a Biomarker for Polycyclic Aromatic Hydrocarbons exposure among Charcoal Workers in Ogun and Oyo States, Nigeria

BACKGROUND: Urinary 1-hydroxypyrene (1-OHP) has been widely used as a biomarker of polycyclic aromatic hydrocarbons (PAHs) in occupationally exposed workers. The objective of this study is to investigate the concentration of urinary 1-OHP among charcoal workers as subjects and non-charcoal workers as controls. METHODS: Early morning urine samples were collected from 68 persons (25 charcoal workers in Igbo-Ora, 20 charcoal workers in Alabata, and 23 non-charcoal workers) who volunteered to participate in this study. 1-OHP determination in urine samples was carried out using high performance liquid chromatography after hydrolysis. Descriptive and inferential statistics were used for data analysis at p < 0.05. RESULTS: The mean urinary 1-OHP concentration (μmol/mol creatinine) among charcoal workers at Igbo-Ora and Alabata and non-charcoal workers were 2.22 ± 1.27, 1.32 ± 0.65, and 0.32 ± 0.26 (p < 0.01). There existed a relationship between respondent type and 1-OHP concentration. Charcoal workers were 3.14 times more at risk of having 1-OHP concentrations that exceed the American Conference of Governmental Industrial Hygienists guideline of 0.49 μmol/mol creatinine than non-charcoal workers (relative risk = 3.14, 95% confidence interval: 1.7–5.8, p < 0.01). CONCLUSION: Charcoal workers are exposed to PAHs during charcoal production and are at risk of experiencing deleterious effects of PAH exposure. Routine air quality assessment should be carried out in communities where charcoal production takes place. Assessment of urinary 1-OHP concentration and use of personal protective equipment should also be encouraged among charcoal workers.