Why do you suppose such man-made chemicals are toxic to plant and animal life and persist in the environment?

Hello Class,

This is our first discussion question, it is optional and for extra credit only. You will need to write out your thoughts, maybe a couple of paragraphs and then add it to the discussion board, please use;

Complete thoughts
Summarize in your own words in paragraph form
Proper Spelling/grammar and punctuation are required
Many organic compounds are man-made chemicals not found in nature. Examples of such chemicals are halogenated organic compounds, organophosphorus compounds and polymers. Such chemicals are often used as herbicides, pesticides and nerve toxins, and often persist in the environment. Styrene made into Styrofoam, for example, is very stable and doesn’t break down when disposed of in landfills. Why do you suppose such man-made chemicals are toxic to plant and animal life and persist in the environment?