A model to predict concentrations of lipophilic chemicals in growing pigs

A model was devised to examine predicted residue concentrations in the fat of growing pigs under various exposure scenarios. A single body fat pool and transfer rates proportional to concentrations were assumed. When exposure was a constant concentration in the diet, predicted concentrations in fat were maximum at about 30 kg body weight and then declined slowly until the typical 100 kg slaughter weight was reached. Declines in concentrations of recalcitrant compounds in fat of animals moved to a clean environment can be accounted for by dilution in the expanding fat pool. Model simulantions suggest that alterations in feeding and management to produce leaner animals may lead to greater transmission of residues to humans.