About Nordic Screening
There are approximately 100.000 different chemical substances in use within the EU borders. We know that some of these are very hazardous and pose a risk to the environment. However, for the vast majority of substances, we simply don’t have the knowledge to decide whether they pose a risk to the environment at the present time or maybe will do so in the future. To better understand such risks, one important first step is to measure these chemicals in the environment, to see whether they can be detected in water, soil or in living organisms. If the substances are persistent, bioaccumulative or toxic (PBT), they are regarded as hazardous. Substances with known hazardous properties are to a large extent regulated and included in national monitoring programs in the Nordic countries.
The aim of the Nordic environmental screening is to obtain a snapshot of the occurrence of potentially hazardous substances, both in regions most likely to be polluted as well as in some pristine environments. The focus is on less known, anthropogenic substances and their derivatives, which either are used in high volumes or are likely to be persistent and hazardous to humans and other organisms.
PFAS in the Nordic environment – a Pandoras box?
The levels of new and unknown PFAS in Nordic environmental samples may surpass those we are currently monitoring.
Per- and polyfluoroalkyl substances (PFAS) is a large class of substances that has become an environmental problem due to extreme persistence and potential toxic effects in biota and humans. While more than 4 000 man-made PFAS are estimated to be in circulation on the global market, the environmental distribution of most of these is poorly understood. The Joint Nordic Screening Group therefore commissioned University of Örebro to perform a chemical screening of an extensive list of conventional and emerging PFAS in the Nordic environment. For this screening, the researchers included methodology to quantify total extractable organic fluorine (EOF). This enables an overview of the total concentration of PFAS, including the substances researchers currently are not able to identify. The results provide a strong indication that the amount of new and non-identified PFAS may surpass the sum of the most common PFAS known today.
Analyses of environmental samples such as bird eggs, fish, marine mammals, terrestrial mammals, surface water, air, WWTP effluents and sludge, showed that the analysis of specific PFASs could explain between 2% and 102% of the measured EOF. The average explanation degree for detected samples can be seen in the graph below along with the range explanation degree for each type of sample.
Shorter chain PFASs with carbon chain lengths of 2-4 were frequently detected in surface water and WWTP effluent. Although having low bioaccumulation potential, they may well be as persistent as their longer chain homologues, and their long-term effects on the environment and humans are unknown. Furthermore, so-called precursor compounds, which are compounds that by degradations end up as PFASs, contributed to the total PFASs, and were frequently detected in many matrices.
The results clearly demonstrate the need to include more PFAS classes in environmental assessments in order to qualify discussions or regulatory discussions aiming at reducing PFAS exposure sources. Moreover, the high quantity of non-identified PFAS in environmental samples may represent a Pandoras box, which needs to be elucidated to further assess environmental and human health risks.
PFASs in the Nordic environment
Authors: Anna Kärrman, Thanh Wang and Roland Kallenborn
Co-authors: Anne Marie Langseter, Siri Merete Grønhovd, Erik Magnus Ræder, Jan Ludvig Lyche, Leo Yeung, Fangfang Chen, Ulrika Eriksson, Rudolf Aro and Felicia Fredriksson.
Publisher: © Nordic Council of Ministers 2019
The report is available for free download at https://norden.diva-portal.org/smash/get/diva2:1296387/FULLTEXT01.pdf