In some Wake County waterways, signs announce to anglers that the fish cannot, under any circumstances, be eaten.
Why it matters: Eating lots of freshwater fish in North Carolina comes with health risks because of the widespread presence of mercury in the environment. Total bans are uncommon, though.
- This one is caused by another contaminant: cancer-causing polychlorinated biphenyls (PCBs).
Flashback: In the 1960s and ’70s, according to government reports, rain rinsed chemicals from an industrial site near the Raleigh-Durham International Airport into a small stream that feeds into Brier Creek, Crabtree Creek and Lake Crabtree.
- The now-closed Ward Transformer Co. was handling electrical equipment like transformers back when they were filled with PCBs.
The intrigue: The same company was fined and its employees criminally prosecuted for dumping PCBs out of trucks on North Carolina roadsides in the late ’70s.
Zoom in: The U.S. government banned the manufacture of PCBs in 1979 “based on mounting evidence that they were toxic to human health and the environment,” per the U.S. Environmental Protection Agency.
- PCBs are synthetic oily liquids that tend not to break down in the environment, sticking to soil and animal tissue. They cause cancer and many other human health issues, researchers have found.
How it works: Predatory fish like catfish and bass are especially hazardous because they’ve not only accumulated chemicals over their lifetimes; they’ve also eaten the chemicals other fish have built up in their lifetimes…