They involved workers exposed to ten or even a hundred times the amount of PCBs common in non-occupational populations, as well as people like those in Rome, who may have had environmental and dietary exposures. Most people are exposed to PCBs through the trace amounts present in their food. PCBs have been found in many foods, including milk, eggs, beef, chicken, and fish. It has been estimated that 95 percent of non-occupational exposure of humans to PCBs occurs through ingestion of common foods. The levels found in foods as well as background levels in the air have been decreasing on a worldwide basis.
Vegetables grown in gardens are unlikely to have significant PCB levels.
Since PCBs tend to adhere to soils, normal food preparation, like washing and peeling, results in removal of substantially all PCBs. These background levels are believed to be mainly a result of eating meats and fish containing low levels of PCBs deposited in the environment. People should follow applicable fish consumption advisories. The concentrations of PCBs in fish have declined significantly since 1976. Fish consumption recommendations remain but have been relaxed for some species and eliminated for others.