The pharmacokinetic behavior of cyclopiazonic acid (CPA) was determined in market weight pigs using a competitive indirect ELISA developed for the determination of the mycotoxin in various biological matrices. Sample preparation for corn and skeletal muscle was achieved with a single extraction and recoveries of 53+/-6% over the effective range of the standard curve. The detection limit of CPA was 1 ppb in plasma, which required no extraction, and 20 ppb in corn and skeletal muscle with average intra- and interassay CV of 11 and 23%, respectively. Levels of CPA contamination in corn grown and stored in Michigan were unremarkable compared with published toxicity thresholds; the highest level of CPA found in any sample was 47 ppb. In pigs given a 20-mg i.v. bolus, CPA distributed rapidly among three compartments, with an overall volume of distribution (49 L) nearly equivalent to total body water. Cyclopiazonic acid was eliminated with a half-life of 24 h. Estimates of these pharmacokinetic parameters were supported by the achievement of steady-state plasma CPA levels within 6 d in pigs consuming a diet containing 10 ppm CPA, and by measured concentrations of CPA in plasma (410+/-44 ng/mL) and skeletal muscle (469+/-86 ng/ g). From these and other data, we concluded that the threat of CPA toxicity to livestock from consumption of cereal grains or to humans from consumption of animal products is minimal.