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

Abstract

BackgroundUrinary 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.MethodsEarly 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.ResultsThe 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).ConclusionCharcoal 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.

Exposure to Wood Smoke and Associated Health Effects in Sub-Saharan Africa: A Systematic Review

“…Titcombe et al [43] reported mean total PAH and benzo(a)pyrene levels of 5040 ± 909 ng/m 3 and 767 ng/m 3 , 334 ± 57 ng/m 3 and 44 ng/m 3 , and <1 ng/m 3 and 0 ng/m 3 in open firewood, charcoal and LPG users, respectively. Charcoal production was associated with higher levels (>0.49 µmol/mol creatinine) of urinary1hydroxypyrene (RR: 3.14, 95% CI: 1.7-5.8, P < 0.01) [18]. Awopeju et al [38] reported median (interquartile range) benzene concentration of 119.3 (82.7-343.7) and 0.0 (0.0-51.2) in passive samplers worn by street cooks and non-street cooks, respectively.…”

“…Concentrations of PAHs were measured in three studies [18,38,43]. Titcombe et al [43] reported mean total PAH and benzo(a)pyrene levels of 5040 ± 909 ng/m 3 and 767 ng/m 3 , 334 ± 57 ng/m 3 and 44 ng/m 3 , and <1 ng/m 3 and 0 ng/m 3 in open firewood, charcoal and LPG users, respectively.…”

“…Occupational exposure to wood smoke were reported in seven studies. These include charcoal production [17][18], bakery [44], fish drying [20,50], garri (cassava) processing [21] and street cooking [38].…”

“…Female gender was associated with higher exposure to wood smoke pollutants [14,[33][34]. Occupational exposure was associated with higher levels of exposure to pollutants [17][18]38]. Other risk factors identified include rainy season [47], cooking indoors [48], use of multiple wood stoves [44] and use of traditional cook stoves [41].…”

“…Higher level of exposure may be seen in individuals with some occupations. These include wild land fire fighters [15], charcoal producers [16][17][18], farmers involved in agricultural burnings [2] and individuals involved in commercial cooking and food processing using wood fuel [19][20][21]. Other significant sources of exposure may include bushfires, consumption of food items preserved or processed with wood smoke [19,[22][23] and the ambient air [24][25].…”