Air Pollutant Distribution in Selected Wood-Fired Bakeries in Calabar Metropolis: Implications for Occupational Health

Abstract

Wood-fired bakery operations may generate particulate and gaseous pollutants that affect workplace air quality. This study assessed air pollutant distribution in selected wood-fired bakeries in Calabar metropolis, Cross River State, Nigeria. The objectives were to measure selected air pollutants, evaluate differences in measured values in comparison with NESREA/WHO standards among selected bakeries, and discuss potential occupational health relevance of the findings. Six (6) bakeries were selected within Calabar metropolis.  Measurements were obtained using a portable multiparameter air quality detector. Measured parameters included PM₂.₅, PM₁₀, carbon dioxide (CO₂), formaldehyde (HCHO), total volatile organic compounds (VOCs), temperature, and relative humidity. Readings at each point were taken for 8hours. Descriptive statistics were calculated, and exploratory one-way analyses of variance were reported to compare mean values for the six bakeries. Bakery-level means ranged from 14.33 to 52.33 µg/m³ for PM₂.₅, 20.33 to 74.33 µg/m³ for PM₁₀, 549.33 to 1,099.67 ppm for CO₂, 0.025 to 0.310 mg/m³ for HCHO, and 0.102 to 1.112 mg/m³ for VOCs. Mean temperature ranged from 32.00 to 38.00 °C and relative humidity from 59.33% to 60.33%. Bakery B1 had the highest means for PM₂.₅, PM₁₀, CO₂ and VOCs, while B5 had the highest mean HCHO concentration. The exploratory ANOVA indicated a difference in CO₂ among bakeries (F = 3.119, p = 0.049), while other comparisons were not statistically significant at α = 0.05. The findings identify variability in measured air quality and recommends improved ventilation, dust control, oven maintenance and more rigorous repeated monitoring.