In some parts of the world food is stored with formalin so it looks fresh forever! This is astonishing, but true (See refs here). As formalin is very bad for health and damages kidneys and liver very quickly, I am looking for a way to remove it.
When I buy fish, I know it has formalin in it. Every fruit I bought has formalin. I remember I bought 2 kilgrams of apples once. And it lasted for 1 month, looking fresh whole time. Then I threw it away.
My question is: how can you remove formalin from food? (Especially fish and fruit). It's best if we can use a chemical found in the kitchen. If not, I'd think one that is found at a chemical store.