To study the effect of processing on polybrominated biphenyl (PBB) levels, milk from four dairy herds containing less than 0.3 ppm (fat basis) of physiologically incorporated PBBs was presented individually into cream, skim milk, butter, and stirred curd cheese. Pasteurized and freeze-dried whole milk, skim milk, and cream, spray-dried whole milk and skim milk, and condensed whole milk were als...