Dioxin

Dioxin

• Dioxins are called persistent organic pollutants (POPs), meaning they take a long time to break down once they are in the environment.
• Dioxins are highly toxic and can cause cancer, reproductive and developmental problems, damage to the immune system, and can interfere with hormones.
• Dioxins are found throughout the world in the environment, and they accumulate in food chains, concentrating mainly in the fatty tissue of animals.
• More than 90% of typical human exposure is estimated by EPA to be through the intake of animal fats, mainly meat, dairy products, fish, and shellfish.

What is Dioxin?

Dioxins refers to a group of toxic chemical compounds that share certain chemical structures and biological characteristics (see figure 1). Several hundred of these chemicals exist and are members of three closely related families:

• polychlorinated dibenzo-p-dioxins (PCDDs)
• polychlorinated dibenzofurans (PCDFs)
• certain polychlorinated biphenyls (PCBs)

Although hundreds of PCDDs, PCDFs, and PCBs exist, only some are toxic, those with the chlorine atoms in specific positions. Counting around the carbon rings, those with chlorines at positions 2, 3, 7, and 8 are toxic (see figure 1). The dioxin-like PCBs have both biphenyl rings in the same plane (flat appearance), which allows them to act like dioxins in the body.

PCDDs and PCDFs are not created intentionally but are produced as a result of human activities like the backyard burning of trash. Natural processes like forest fires also produce PCDDs and PCDFs. PCBs are manufactured products, but they are no longer produced in the United States.

Source:  https://www.epa.gov/dioxin/learn-about-dioxin