Depending where you are, that worry might be greater with foraged berries, mushrooms etc. I live in an area that's been heavily industrialised for over 150 years. The soil at my mom's place when tested had too much lead and PCBs for safety. And not too long ago they found leaking barrels of nuclear waste from the 1940s in a lovely wooded area just a couple blocks over from my old primary school. Only God knows what's in the soil here, unless you test it.