Time series data (2008-2023) of polychlorinate d dib enzo-p-dioxins, dibenzofurans and polychlorinated biphenyls in bivalves from Shellfish Production Areas of the Basque coast (SE Bay of Biscay)

The accumulation of contaminants in aquatic organisms is of concern to human health due to the potential for ex-posure through the consumption of seafood. This dataset presents the levels of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and 12 dioxin-like polychlo-rinated biphenyls (DL-PCBs) (PCB-81, PCB-77, PCB-126, PCB -169, PCB-123, PCB-118, PCB-114, PCB-105, PCB-167, PCB-156, PCB-157 and PCB-189) in bivalves collected annually between 2008 and 2023 from the four Shellfish Production Areas of the Basque coast (southeastern Bay of Biscay). Additionally, data on 6 non-dioxin like polychlorinated biphenyls (NDL-PCBs) (PCB-28, PCB-52, PCB-101, PCB-153, PCB-138 and PCB -180) is provided for the 2012-2023 time period. Depend-ing on the availability of bivalves at each Shellfish Produc-tion Area, different species, such as mussels (Mytilus gallo-provincialis) and oysters (Magallana gigas and Ostrea edulis) were used for the evaluation. Bivalve samples were analyzed at the accredited Laboratory of Dioxins of the Institute of Environmental Assessment and Water Research -CSIC in Spain, following standardized methodologies according to the specific requirements established at the correspond-ing EU Regulation. Concentrations and the World Health Organization-Toxic Equivalents (WHO-TEQ) were calculated. Considering the data from the four Shellfish Production Ar-eas and the study period, WHO-TEQ values ranged from 0.12 to 0.64 pg g -1 wet weight for PCDD/Fs and from 0.45 to 2.23 pg g -1 wet weight for DL-PCBs, whereas concentrations ranged from 7.45 to 51.10 ng g -1 wet weight for NDL-PCBs. This database is useful for (i) assessing the spatial and tem-poral trends of PCDD/Fs and various PCBs in bivalves from the Basque coast, (ii) determining the relative contribution of different congeners, (iii) comparison with levels for human consumption and environmental quality standards, as well as with levels of other biogeographical areas, and (iv) the man-agement of Shellfish Production Areas on the Basque coast. (c) 2023 Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

Automated summary

This dataset presents the levels of PCDD/Fs, DL-PCBs, and NDL-PCBs in bivalves collected from the Basque coast between 2008 and 2023. The data is useful for assessing trends, determining contributions, comparing with standards, and managing shellfish production areas.