What is the definition or description of: Mercury in fish?

What is says. Mercury is released into the air from industrial activities, mostly burning of coal. It is take up by marine organisms that are then eaten by fish and mercury accumulates in the top predators. Consult this site for more info: http://www.webmd.com/food-recipes/tc/avoiding-mercury-in-fish-topic-overview#1 For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.