Chemical agents that can occur as by-products of industrial pollution and be consumed by humans are

Polychlorinated Biphenyls.

Explanation:

Polychlorinated Biphenyls are man-made chemicals. They are solids, and oily liquid in structure with no taste or small, yellow to clear in color. PCBs are present as a mixture, and very stable at an extreme pressure, and temperature. Basically they are used in electrical equipment such as transformers, and capacitors. High level of PCBs can cause broad spectrum of effects in humans, for example:

1) Increase some liver enzyme level, and cause hepatic damage.

2) Respiratory problems.

3) Dermal lesions.

explanation:

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.

two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.