Decadal Trends in Polycyclic Aromatic Hydrocarbon (PAH) Contamination Assessed by 1-Hydroxypyrene in Fish Bile Fluid in the Netherlands: Declining in Marine Waters but Still a Concern in Estuaries

Abstract

Long-term monitoring data on the concentrations of biliary 1-hydroxypyrene (1-OHPyr) in flatfish, as a biomarker for polycyclic aromatic hydrocarbon (PAH) exposure, were analyzed and evaluated to elucidate spatial differences and temporal trends in marine and estuarine PAH contamination in the Netherlands. Dab (Limanda limanda) and flounder (Platichthys flesus) with partly overlapping distributions were used as target species. In total 1831 bile samples were analyzed individually: 417 dab in 1998-2005 and 1438 flounder in 1996-2012. The sampling procedure for flatfish and the PAH metabolites determination by means of high performance liquid chromatography (HPLC) with fluorescence (FL) detection were based on international guidelines. Measuring the absorbance at 380 nm was tested to correct for possible differences in feeding status, but this turned out not to be a suitable parameter for the standardization of PAH metabolite concentrations. Both fish species showed statistically significant differences in biliary 1-OHPyr concentrations between various locations. The highest level of PAH contamination was found in flounder from the estuarine Western Scheldt, which might be partly due to local dredging activities. Dab from the central North Sea (Dogger Bank) showed the lowest level of PAH contamination. Analysis of all the data indicated mainly downward trends in PAH contamination, most clearly pronounced in the Dutch Wadden Sea. PAH exposure levels in the Dutch coastal waters including the Eastern Scheldt and the Wadden Sea, and also at the offshore North Sea monitoring sites represent levels of response that are not indicative of significant harm. In contrast, PAH contamination in the more industrialized Dutch estuaries (Western Scheldt and Ems-Dollard) is still a cause Vethaak et al.Marine and Estuarine PAH Contamination for concern. Future monitoring should register the total bile volume, the sex of the fish and the method of fishing to improve the interpretation of the data. In addition, the biliary absorbance at 380 nm should be registered as it may help the interpretation of outliers in the data.

UK long-term monitoring dataset: assessing factors affecting biomarkers commonly used in environmental programmes

“…Our results mirror the UK status and trend assessment findings for bile metabolite in dab from the UK biogeographic regions, covering the period of 2010 to 2015, where PAHs were found to be unlikely to cause adverse biological effects (Nicolaus et al, 2018a). As also shown by other authors, PAH metabolites analysis in dab and flounder bile allowed to discriminate between distinctly impacted sampling sites (Richardson et al, 2001;Kammann, 2007;Devier et al, 2013;Vethaak et al, 2016), making it a reliable indicator of dab exposure to PAHs.…”

“…Well established biomarkers, such as hepatic EROD and biliary 1-OH pyrene have been shown to allow discriminating between distinctly impacted sampling sites, however factors such as season (sexual maturity), gender, nutritional status (condition factor) and age can affect these parameters in fish species used in monitoring programmes (Sleiderink et al, 1995b;Kammann et al, 2005;Kammann, 2007;Devier et al, 2013;Vethaak et al, 2016). There is however less work reported for other established biomarkers, like acetylcholinesterase inhibition for flatfish species (Kirby et al, 2000).…”

Impacts of chemical stress, season, and climate change on the flounder population of the highly anthropised Seine estuary (France)

“…The levels of flounder bile hydroxypyrene showed that concentrations were 4 to 17 times higher, respectively, in Seine vs North Sea-Holland and in Seine vs Iceland (Kamman et al 2017). We suggest that the intensive dredging activities conducted in the Seine to maintain the navigation channel depth could be a major factor increasing the flounder contamination by PAHs in this estuary, as described in other industrial estuaries in Europe (Vethaak et al 2016).…”

Dependence of element composition of bile of freshwater and marine fishes on some abiotic and biotic factors

“…The intraspecific variability is mainly explained by differences in body mass of fish. Indeed, the factors that determine the relative volume of fish bile include fish size, age, and gut fullness (Vethaak et al, 2016). We have found that the volume of bile per gram of fish was significantly and negatively correlated with gut fullness of fish.…”