Persistent Organic Pollutants (or ”POPs” for short) are chemicals which are considered to have adverse effects on living organisms and are also known to persist for long periods of time in the environment without breaking down. Indeed some chemicals were used for precisely these reasons: insecticides and fungicides were used as they were toxic to certain organisms, while flame retardants and oil/water repellents were required to last years without breaking down (in addition to other desirable chemical properties). However, despite their effectiveness, some of these chemicals were found to be particularly hazardous to the environment and toxic at sufficient doses. Some of the more hazardous of these compounds prompted the inception of the Stockholm Convention on Persistent Organic Pollutants, a United Nations convention which aims to regulate the production and use of certain hazardous and persistent chemicals.

PFOS chemical symbol

‌Among these chemicals are the brominated flame retardants hexabromocyclododecane (HBCDD) and polybrominated diphenyl ethers (PBDEs), ‌many of the ‌commercial mixtures of which are now banned or heavily restricted under both UN and EU legislation. Another chemical of interest is perfluorooctane sulfonic acid‌ polybrominated diphenyl ethers(PhexabromocyclododecaneFOS), a chemical used as a fabric protector and stain repellent, the use of which is now also heavily restricted under EU law. These compounds have all been used extensively over the past few decades in various items such as electronics and soft furnishings, thus large quantities now exist in end-of-life consumer goods, much of which was ‌(and still is) landfilled. The leaching of these chemicals into the regions surrounding landfills is a major cause for concern and the extent to which it may be occurring in Ireland is not yet clear. This project aims to bridge this knowledge gap and initiate the first steps towards mitigating or even eliminating the threat these chemicals can pose to the environment.

polybrominated diphenyl ethers (PBDEs)