Formalin in food

I bought some fish from Karwan Bazar wholesale market and found that formalin had been applied to it. I bought fish several times in the past and the same thing happened every time. Who is responsible for this? I think traders are taking the chance as there is nobody to check the matter.
My suggestion is: appoint permanently two well equipped teams headed by two magistrates for wholesale markets of Dhaka city who can check fish, fruits, vegetables and other food items regularly.
The govt should take the necessary steps immediately to protect the consumers.