POPs

What are POPs?

There’s increasing concern about the growing mass of our discarded plastics – yet not because of their direct effects on wildlife (e.g. entanglement), but because plastics could be a crucial vector for the transport of key environmental contaminants: persistent organic pollutants, or POPs.

There are many thousands of POP chemicals, originating from agriculture, combustion processes, industrial syntheses, and products such as flame retardants, plasticisers and antimicrobials. In fact, our understanding and classification of them is ever evolving. They’re named not because of their chemical groups, but because of their behaviour. As the name “persistent organic pollutants” suggests, they’re long-lived and harmful.

Plastic debris on a beach. By epSos.de (Flickr).

What chemicals are we talking about?

Mosquito – By Alvesgaspar via Wikipedia Commons.

Typical culprits include DDT, polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), halogenated flame retardants, and polybrominated diphenyl ethers (PBDEs). Although DDT is now banned in most countries, it’s still permitted in some places with a high incidence of malaria to fight off mosquitoes^[1].

POPs are polluting and persistent because of certain properties, such as their solubility, reactivity and volatility.