When pollution is caused by nutrients and fertilizers, this is called nutrient pollution, and it leads to an overproduction of algae and other aquatic plants. This overabundance of plants and algae causes problems, because they cover the water surface and prevent sunlight from reaching the plants underwater.
Reverse T3 is actually an antithyroid -- T3 is the active thyroid that goes to the cells and stimulates energy and metabolism. Reverse T3 is a mirror image -- it actually goes to the receptors, sticks there, and nothing happens. So it blocks the thyroid effect. Reverse T3 is kind of a hibernation hormone, in times of stress and chronic illness, it lowers your metabolism.
Free T3 and Total T3. 1  A free or total triiodothyronine (free T3 or total T3) test is used to assess thyroid function. 2  T3 and T4 (thyroxine) are hormones produced by the thyroid gland. 3  Most of the T4 and T3 circulates in the blood bound to protein, while a small percentage is free (not bound).