Exposure of pig fatteners and dairy cows to polycyclic aromatic hydrocarbons

Exposure of pig fatteners and dairy cows to polycyclic aromatic hydrocarbons (PAHs) was investigated by analyses of selected indoor and outdoor samples. PAH concentrations (16 U.S. EPA priority PAHs) and data on common exposure routes were used for exposure calculations. The samples under study included water (n = 24), feed (n = 48), indoor air (n = 15), barn dust (n = 17), outdoor air (n = 6) road dust (n = 17), and soil (n = 15) collected in the summer 1999 and in the spring 2000 on 3 pig and 2 dairy cattle farms. The following mean concentrations of 16 PAHs were found: 100 ng/l in water for pigs, 38 ng/l in water for cows, 82 µg/kg in feed mixtures for pigs, 128 µg/kg in feed concentrates for cows, 278 µg/kg in forages for dairy cows, 25 ng/m3 in indoor air of pig houses, 59 ng/m3 in indoor air of cow houses, 676 µg/kg in dust collected in pig houses, 4 475 µg/kg in dust collected in cow houses, 16 ng/m3 in outdoor air of pig houses, 29 ng/m3 in outdoor air of cow houses, 4 711 µg/kg in road dust collected on pig farms, 15 175 µg/kg in road dust collected on cattle farms, 826 µg/kg in soil collected around pig houses, and 1 356 µg/kg in soil collected around cow houses. The total intake of 16 PAHs in the diet of cows and pigs was 14 156 µg and 164 µg PAHs per day, respectively. The exposure of cows to PAHs was 86 times higher than that of pigs. Feed was the major source of PAHs for both species (approximately 99%). Urinary 1-hydroxypyrene concentration was used as a biomarker of exposure to PAHs. The mean total amount of 1-hydroxypyrene excreted per day in porcine (2 l) and bovine (13 l) urine was 14.5 µg and 1 595 µg, respectively, which was 3.2% and 11.9% of pyrene intake.