My Japanese anthropology professor once told us a story about when he and his wife went to Japan for a research trip with his wife sometime in the 70s or 80s.
In Japan, when you move into a new apartment, it's customary to give a gift to your neighbors. Being a new professor, he and his wallet welcomed any chance to save a little money. When he and his wife were walking along a beach in the Tokyo Bay area, they noticed a ton of shellfish.
Thinking this would be a great gift and a budget dinner, they got some buckets, went back, and started pulling up shellfish for dinner and for their neighbors as a present.
The Tokyo Bay was much more polluted in that era (not that I know whether it would be safe to do this now), so when everyone ate those shellfish, apparently everyone got terribly sick.
So yeah, I'd be super leery of edible things in those kinds of areas in general. :(
Pollution in Japan caused a number of issues in the 60s, things were probably starting to get better in the 70s when their environmental agency was formed, but no doubt issues remained.
I'd be surprised if even back in the 70's that Tokyo bay was so polluted that pollution-contaminated shellfish could make people sick immediately. Seems more likely that it was some kind of bacterial, algae or biotoxin poisoning (which can happen even in unpolluted waters)
With longer term exposure, sure I could see health effects, but not from a single meal. Even under stringent environmental regulation, I'd avoid seafood caught in any large city's bay, since decades old contamination can still cause problems today.
In Japan, when you move into a new apartment, it's customary to give a gift to your neighbors. Being a new professor, he and his wallet welcomed any chance to save a little money. When he and his wife were walking along a beach in the Tokyo Bay area, they noticed a ton of shellfish.
Thinking this would be a great gift and a budget dinner, they got some buckets, went back, and started pulling up shellfish for dinner and for their neighbors as a present.
The Tokyo Bay was much more polluted in that era (not that I know whether it would be safe to do this now), so when everyone ate those shellfish, apparently everyone got terribly sick.
So yeah, I'd be super leery of edible things in those kinds of areas in general. :(