A toxic substance can be defined as any chemical or mixture with an inherent ability to cause systemic damage to living organisms.  Toxic substances occur in the air, the soil, the water and in other living things, and they can enter the body in various ways:

-through ingestion – by eating and drinking;
-through inhalation – by breathing;
-by absorption – through contact with the skin; and
-by injection – from a hypodermic syringe, for example, or from an insect, spider or snake bite.

There are naturally occurring toxins found in certain plants like poinsettias and wild mushrooms and berries. However, the toxic substances contained in most everyday household products are are man-made and contain polychlorinated biphenyl (PCB).  Some of the products are drain cleaners, oven cleaners, laundry detergents, floor or furniture polish, paints and pesticides.

The Toxic Substances Control Act of 1976 specifically regulates polychlorinated biphenyl (PCB) products. The TSCA provides the Environmental Protection Agency (EPA) with authority to require reporting, record-keeping and testing requirements, and restrictions relating to chemical substances and/or mixtures.  Food, drugs, cosmetics and pesticides are excluded from the purview of the Act.