Question

What kind of chemicals are the "dirty dozen" POPs? Why are they on a list?

Short answer

The 'dirty dozen' POPs are a list of 12 dangerous chemicals, including DDT, PCBs, and different forms of dioxin. They are listed due to their harmful characteristics; they're toxic, they persist in the environment, and they can accumulate in the food chain. The list comes from The Stockholm Convention, which seeks to control these pollutants.

Step-by-step solution

Identifying the Dirty Dozen POPs

Firstly, it's important to know that the 'dirty dozen' refers to a group of 12 toxic chemicals. These chemicals are: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, toxaphene, polychlorinated biphenyls (PCBs), and two forms of dioxin — 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated dibenzofurans (PCDFs).

Understand why they are on a list

The 'dirty dozen' POPs are listed due to their harmful characteristics. These chemicals are toxic, persist in the environment for long periods of time, and can accumulate and pass from one species to the next through the food chain. This makes them a significant concern for human health and the environment. Due to these characteristics, they are subject to international regulations.

Discuss The Stockholm Convention

The inclusion of these 'dirty dozen' POPs in a list comes from The Stockholm Convention, an international environmental treaty, signed in 2001 and effective from May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants.