For thousands of years, species lived in earth exposed to what nature and evolution did bring to the plate. So many combinations of atoms into molecules populated this planet. Until mankind learned to handle those pesky atoms and started exploring new combinations.
Unimaginable sorts of materials, chemicals, and even living entities started to come out of our laboratories. Combinations than never were, now are.
We only do not know how our bodies, and most importantly our brains work. And how those new combinations will react with our organs. Yet the pace of technological advances and new combinations of atoms that become part of our world grows every day at always faster rate.
We have learned to fear radioactivity, yet radioactivity has been present in our world since the very beginning. We even believe we feel uneasy in the neighborhood of a nuclear power plant. At the same time we embrace new materials, chemicals and drugs. We sit for hours in vehicles made of large bits of plastic that exhude organic components in the air, we use ever more effective pesticides and ingest ever newer drugs with the hope they will make us feel better.
At last all ends up entering our bodies. And the bodies of those other few species that we have not yet wiped out.