Why are PCBs harmful to human health and the environment?

Why are PCBs harmful to human health and the environment?

PCBs have been linked to human cancer as well as liver dysfunction, digestive disorders, chloracne, headaches, nausea, and fatigue. PCBs can also affect the respiratory, immune, nervous systems and cause a variety of reproductive disorders, including male sterility, developmental abnormalities, learning disorders and birth defects.

When released into the environment, PCBs do not easily break apart and form new chemical arrangements (i.e., they are not readily biodegradable). Instead they persist for many years, bioaccumulate, and bioconcentrate in organisms. Well documented tests on laboratory animals show that various levels of PCBs cause reproductive effects, gastric disorders, skin lesions, and cancerous tumors. Exposure to PCBs in humans can cause chloracne (a painful, disfiguring skin ailment), liver damage, nausea, dizziness, eye irritation, and bronchitis.

PCBs may enter the body through the lungs, the gastrointestinal tract, and the skin. After absorption, PCBs are circulated in the blood throughout the body and are stored in fatty tissues and a variety of organs, including liver, kidneys, lungs, adrenal glands, brain, heart, and skin. PCBs pervade the environment. Measurable amounts of PCBs have been found in soils, water, fish, milk and human tissue.