Polychlorinated biphenyl- and triphenyl-induced gastric mucosal hyperplasia in primates.

Polychlorinated biphenyl or triphenyl ingestion by subhuman primates for 3 months produced hyperplasia and dysplasia of the gastric mucosa. The concentration of the biphenyl within the experimental diet was less than an order of magnitude greater than that occurring in random food samples sold in the United States and less than levels which have occurred in food products as a result of industrial accidents. The increased cellularity, abnormal dysplastic growth pattern, and invasion of the adjacent tissue region indicate compromised gastric function and are suggestive of an eventual neoplastic transformation.