Les, you remind of those days, about 40-50 years ago, when DDT was still in use on just about everything, and ads were run to warn of the passage and concentration of the chemical through the biological food webs. They had one, with the picture of a mother nursing her baby. I don't remember the exact caption of the picture, but it went something to the effect that the baby was picking up a concentrated share of DDT in the mother's milk.