A literature review as an introduction for a paper, about the heavy metals in edible fish (not general seafood) in Qatar (or the Arabian gulf countries), the resources of heavy metals, how it affect the fish, and why it is important to study it, and the recent changes happening to the water that affect the fish.
All from recent references and from the closer area of our study

no need to explain what is heavy metals!!! or any definitions

it need to be very comprehensive with useful information only