320 An evaluation of the heavy metal content in inhalable and small PM broiler house sample fractions of broiler house dust in Dinokeng, South Africa

Studies indicated that settled broiler house dust and used broiler house floor bedding contains heavy metals which are considered to have high toxicity. Current literature does not indicate if heavy metals are present in airborne broiler house dust. Inhalable and small PM broiler house airborne dust was collected in a broiler house to determine if heavy metals are present.NIOSH method 7300 was used to determine particulate matter larger than 7 μm and smaller than 7 μm inside the broiler house and the particulate matter larger than 7 μm outside the broiler house on day 0 (background), 20 and 40. The duration of sampling was eight, seven and three hours for day 0, 20 and 40 respectively. Bulk samples of the chicken feed, sawdust, clean and used floor bedding were also collected.SEM-EDX analysis was done with a Thermo Scientific Phenom XL G2 Desktop SEM to determine elemental composition of the PM and bulk samples collected.The broiler house PM contains cadmium and chromium in atomic concentrations of more than 10%, and manganese, nickel, arsenic, selenium, and mercury in atomic concentrations of less than 10%. The atomic concentrations of cadmium are most likely due to the processing and production of the chicken feed. The origins of the atomic concentrations of chromium could not be identified.The unique method used to identify heavy metals highlighted that other variables besides the amount of inhalable and respirable broiler house dust needs to be considered during an occupational health risk assessment of broiler house workers.