Question

what is the main concern about toxic chemicals in the oceans? they can bioaccumulate and enter the food chain. they are easily eliminated by natural processes. they are harmless and only affect marine species.

Explanation:

Toxic chemicals in oceans can accumulate in organisms over time and move up the food - chain, causing harm to various levels of the ecosystem. They are not easily eliminated by natural processes and are not harmless.

Answer:

They can bioaccumulate and enter the food chain.