PROGRAMME

Anthropogenic activities are one of the main contributors to the introduction of organic micropollutants in the environment. During the past decades, the environmental research was focused on the detection of priority pollutants (PPs), for which mitigation measures have been applied due to their persistent, bioaccumulative and toxic (PBT) properties. However, recent findings suggest the significant presence of emerging contaminants (ECs) in various environmental compartments. These contaminants are not properly monitored or regulated, and they are linked with suspected detrimental effects on both human health and the ecosystem, and, therefore, are candidates for future regulation. Thus, their systematic monitoring is of high importance, due to their high detection frequency and potential harmful properties. Biomonitoring data can be used for risk assessment of pollutants and for substance assessment through the development of guidance in relation to exposure and bioaccumulation. As a result, it helps with the evaluation of the effectiveness of chemical regulations, to protect the environment, wildlife and human health. Apex predators, such as otters, are commonly used for biomonitoring studies of ECs, since they possess many key characteristics that make them ideal organisms for detecting and evaluating contaminants in the environment. The majority of the biomonitoring studies of organic micropollutants investigate only the presence of PPs, and focus solely on specific chemical classes, such as PFAS (O’Rourke et al. 2022). Thus, many organic micropollutants remain uninvestigated and the chemical exposure of biota species is not explored at a high extent. The aim of this study is the determination of the chemical fingerprint of organic micropollutants, by applying generic sample preparation protocols for the extraction of LC and GC amenable compounds with different physicochemical properties and using LC- and GC- HRMS techniques and novel wide-scope target analysis protocols. In this framework, otter samples gathered from the United Kingdom were analyzed to investigate the occurrence of >2,400 organic micropollutants and their accumulation profile in seven different tissues collected during post mortem of road-killed otters, (muscle, liver, kidney, pelt, blood, fat and faecal samples). In total 91 organic micropollutants, from different chemical classes, were determined. The dominant class were pharmaceuticals and their transformation products (TPs) (25%), following by PFAS and plant protection products (17%). 17 conventional (PFCAs, PFSAs) and new (e.g., 6:2 FTS, 6:6 PFPi) PFAS, as well as branched isomers of PFOA and PFOS were detected in all the different tissues. The most polluted matrix, in respect to the number of detected contaminants, was pelt, with 45 compounds identified, 35.6% of which were pharmaceuticals, antidepressants, and antipsychotic drugs. Therefore, this matrix, which could potentially be acquired non-invasively, may be of interest for the systematic monitoring of polar and semi-polar chemicals (including pharmaceuticals) in otter samples. 42 and 32 compounds were determined in the liver and kidney samples respectively in high concentration levels and with high % frequency of appearance. 32 compounds were rarely present in low concentration levels in faecal samples. 23 and 24 compounds, mainly PFAS, were detected in low concentration levels in the muscle tissue and blood samples, respectively. The least polluted matrix was fat tissue.