Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans in cattle raised at agricultural research facilities across the USA and the influence of pentachlorophenol-treated wood.

Adipose tissue samples from 158 cattle raised locally at experiment stations across the USA were analysed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F). While 80% of the samples had PCDD/F concentrations that fell within the range of a previous US survey of beef animals (not detected -4.1 ppt toxic equivalency), several animals had exceptionally high concentrations (8-54 ppt toxic equivalency).

Effects of clenbuterol on body stores of polychlorinated dibenzofurans (PCDF) and dibenzo-p-dioxins (PCDD) in rats.

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF), persistent pollutants that accumulate in the food chain, pose a risk to humans through consumption of tainted livestock. Clenbuterol, a leanness-enhancing agent, was tested for usefulness in PCDD/F body store reduction through body fat reduction (the predominant site of accumulation). To mimic the situation of contaminated animals, rats were given feed with or without a mixture of PCDD/F (0.

Treated wood in livestock facilities: relationships among residues of pentachlorophenol, dioxins, and furans in wood and beef.

Wood and other environmental samples were collected from sites that produced beef with higher than average residues of dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF). Analyses of these samples for PCDD/Fs and pentachlorophenol (PCP) indicated that the high beef residues were associated with PCP-treated wood in the animal facilities. Concentrations of PCDD/Fs in wood as toxic equivalents ranged from 10 to 320,000 pg/g.

Metabolism of [14C]1,2,7,8-tetrachlorodibenzo-p-dioxin in a ruminating Holstein calf.

1. [UL-7,8-ring 14C]-1,2,7,8-tetrachlorodibenzo-p-dioxin (1278-TCDD) was administered orally to a ruminating Holstein bull calf (43.6 kg; 1.

Metabolism of N-isopropylacetanilide in rat.

1. Radioactivity from oral doses of N-isopropyl[1-14C]acetanilide was excreted in urine (53.5%), faeces (8.