peer reviewed | This study investigates essential (Mg, Ca, Fe, Mn, Cu, Zn, Se, Ni) and non-essential (Li, Be, Cr, Rb, Sr, Cs, Cd, Sn, Ba, and Pb) element concentrations and stable isotope (δ13C, δ15N, δ34S) compositions in feathers of Brown Boobies (Sula leucogaster) from three distinct Atlantic islands: the Archipelagos of Saint Peter and Saint Paul (SPSP), Abrolhos, and Cagarras. We aimed to investigate the ecological and environmental factors influencing these seabird populations and assess potential variations in contaminant exposure and dietary habits based on location, sex, and maturity stages. Our finding revealed significant geographical differences in trace element concentrations. The Brown Boobies from Cagarras had higher concentrations (mean ± SD, μg g-1) of Fe (29 ± 20) and Mn (0.82 ± 0.82) than those from Abrolhos (Fe: 21 ± 20; Mn: 0.24 ± 0.09) and SPSP (Fe: 15 ± 16; Mn: 0.21 ± 0.06). Tin concentrations were also higher in Cagarras (Sn: 0.02 ± 0.01) than in SPSP (Sn: 0.01 ± 0.01). Our analyses revealed significant differences in Li, Mg, Rb, and Zn concentrations between adults and juveniles. However, there were no sex-related differences in element concentrations within each locality. SIBER analyses revealed distinct dietary differences among the three Brown Boobies populations, with the Cagarras seabirds occupying a higher trophic position compared to the SPSP population. This study highlights the importance of considering different populations to understand contaminant exposure and ecological dynamics in Brown Boobies along the South Atlantic. The Cagarras population shows significantly higher contaminant levels, likely due to proximity to anthropogenic activities. These results highlight the necessity for ongoing monitoring to evaluate long-term effects on the more impacted population and to ensure seabird health and sustainability in the Atlantic Ocean.

Temporal trends for concentrations of mercury (Hg), lead (Pb) and cadmium (Cd) were evaluated from year 2000–2020 in 20 (Hg), 23 (Pb) and 11 (Cd) watercourses in remote forest catchments in Europe. Decreasing trends were observed in 15% (Hg), 39% (Pb) and 45% (Cd) of the watercourses during the period of evaluation. Decreasing trends were mainly observed between 2000 and 2005 for Hg and between 2000 and 2015 for Pb and Cd. For the last five years of the studied time period (2015–2020), more watercourses showed significant increasing, rather than decreasing Hg, Pb and Cd trends. This was interpreted as a legacy effect of metals still retained in catchment soils. The overall negative trends during the earlier part of the study period were likely driven by declining deposition of metals over Europe, especially for Pb and Cd. Other changes related to metal transport and chemistry may have contributed to the observed trends as well, including recovery from acidification and the ongoing browning of surface waters at northern latitudes. Here we found that organic carbon could explain the seasonal variation in Hg and Pb, but was not related the interannual trends. This study highlights the need for long-term monitoring and robust statistical methods that can detect multidirectional, long-term change in water chemistry. | publishedVersion

peer reviewed | Metconazole (MEZ), a chiral triazole fungicide, produces enantioselective adverse effects in non-target organisms. Among MEZ's isomers, cis-MEZ displays robust antimicrobial properties. Evaluating MEZ and cis-MEZ's toxicity may mitigate fungicide usage and safeguard non-target organisms. Our study evaluated the toxicity of MEZ and its cis-isomers at concentrations of 0.02, 0.2, 2, and 4 mg L−1. We report stereoselectivity and severe cardiovascular defects in zebrafish, including pericardial oedema, decreased heart rate, increased sinus venous and bulbous arteries distances, intersegmental vessel defects, and altered cardiovascular development genes (hand2, gata4, nkx2.5, tbx5, vmhc, amhc, dll4, vegfaa, and vegfc). Further, MEZ significantly increased oxidative stress and apoptosis in zebrafish, primarily in the cardiac region. Isoquercetin, an antioxidant found in plants, partially mitigates MEZ-induced cardiac defects. Furthermore, MEZ upregulated the Wnt/β-catenin pathway genes (wnt3, β-catenin, axin2, and gsk-3β) and β-catenin protein expression. Inhibitor of Wnt Response-1 (IWR-1) rescued MEZ-induced cardiotoxicity. Our findings highlight oxidative stress, altered cardiovascular development genes, and upregulated Wnt/β-catenin signaling as contributors to cardiovascular toxicity in response to MEZ and cis-MEZ treatments. Importantly, 1R,5S-MEZ exhibited greater cardiotoxicity than 1S,5R-MEZ. Thus, our study provides a comprehensive understanding of cis-MEZ's cardiovascular toxicity in aquatic life. © 2024 Elsevier Ltd

The production and consumption of plastic products had been steadily increasing over the years, leading to more plastic waste entering the environment. Plastic pollution is ubiquitous and comes in many types and forms. To enhance or modify their properties, chemical additives are added to plastic items during manufacturing. The presence and leakage of these additives, from managed and mismanaged plastic waste, into the environment are of growing concern. In this study, we gauged, via an online questionnaire, expert knowledge on the use, characteristics, monitoring and risks of plastic additives to the marine environment. We analysed the survey results against actual data to identify and prioritise risks and gaps. Participants also highlighted key factors for future consideration, including gaining a deeper understanding of the use and types of plastic additives, how they leach throughout the entire lifecycle, their toxicity, and the safety of alternative options. More extensive chemical regulation and an evaluation of the essentiality of their use should also be considered. | publishedVersion

In the present study, polyethylene (PE) microplastics (150–300 μm) were added to Atlantic cod (Gadus morhua) feeds at 1 %, either in their present form (Virgin PE) or spiked with PCB-126 (Spiked PE). The feeds were given to juvenile cod for a 4-week period. The fish grew from 11 to 23 g with no significant difference between dietary treatments. Cod fed spiked PE showed a significantly higher concentration of PCB-126 in liver and muscle samples compared to control and fish ingesting virgin PE. In accordance with the accumulation of PCB-126 in the liver, the expression of hepatic cyp1a was higher in cod fed spiked PE. Notably, we observed that spiked PE, as well as virgin PE, have an effect on skin. Overall changes indicated a reduced skin barrier in fish fed a diet containing PE. Indicating that PE itself through interaction with gut tissue may influence skin health in fish. | PCB-126 spiked to polyethylene microplastic ingested by juvenile Atlantic cod (Gadus morhua) accumulates in liver and muscle tissues | publishedVersion

Plastic debris is a significant threat to marine and coastal ecosystems. Previous research found that waves, wind, as well as density, size, and shape of microplastics, drive their transport and dispersion. In this paper, a set of laboratory experiments on the effect of waves and wave-induced currents on the input rate and cross-shore transport and dispersion of different types of plastic debris, including the macro and mesosizes, in addition to microplastics is presented. 15 plastic-debris types characterized by different sizes, shapes, and densities, including facemasks, were analyzed under regular and irregular wave conditions. The results show that input and transport rates of plastics depend on their terminal velocities and wave steepness. Plastics with higher settling velocities under less-steep wave conditions are likely to escape coastal entrapment and end up in the breaking zone. However, plastics with greater buoyancy rates under steeper waves show a predominant accumulation closer to the shoreline. | P.N. is supported by a Margarita Salas post-doctoral fellowship funded by 638 European Union-NextGenerationEU,Ministry of Universities and Recovery Trans639 formation and Resilience Plan, through a call fromthe University of Cantabria. The 640 financial support from the Government of Cantabria through the FÉNIX Program 641 (ID 2020.03.03.322B.742.09) is warmly acknowledged. We acknowledge M.S. and the IHLab-Hydro team for all the technical support.

Northern Dvina River is one of the largest rivers in the European Arctic flowing into the White Sea through the populated regions with developed industry. Floating plastics include microplastics (0.5–5 mm) and mesoplastics (5–25 mm) were observed on seasonal variations in the Northern Dvina River mouth. The samples were collected every month from September to November 2019 and from May to October 2020 with a Neuston net that was togged 3 nautical miles in the Korbel'nyy Branch of the River delta. Chemical composition of the plastic particles was determined using a Fourier transmission infrared spectrometer. The majority of the microplastics were identified as polyethylene 52.6%, followed by polypropylene 36.8%. After estimating the export fluxes of microplastics from the Northern Dvina River to the Arctic, there is no significant seasonal variation of the river export of microplastics. The microplastics export rate during the spring flood period in May turned out to be maximum, 58 items/s, while the minimum discharge was in September with a value of 9 items/s. The average weight concentration of microplastics was 18.5 μg/m3, which is higher than it was found in the Barents Sea – 12.5 μg/m3 and several times higher than in the Eurasian Arctic on average - 3.7 μg/m3. These results indicate that the Northern Dvina River is being one of the main sources of microplastic pollution of the White and the Barents Seas. | publishedVersion

The northern fulmar Fulmarus glacialis ingests a larger number of (micro)plastics than many other seabirds due to its feeding habits and gut morphology. Since 2002, they are bioindicators of marine plastics in the North Sea region, and data are needed to extend the programme to other parts of their distribution areas, such as the Arctic. In this study, we provide data on ingested plastics by fulmars collected in 1997 in Kongsfjorden, Svalbard. An extraction protocol with KOH was used and for half of the birds, the gizzard and the proventricular contents were analysed separately. Ninety-one percent of the birds had ingested at least one piece of plastic with an average of 10.3 (±11.9 SD) pieces. The gizzards contained significantly more plastics than the proventriculus. Hard fragments and polyethylene were the most common characteristics. Twelve percent of the birds exceeded the EcoQO value of 0.1 g. | publishedVersion

Embargo until 29 December 2022. | We exposed twelve mesocosm stream channels and four instream channels to one, two, and four pulses of the insecticide lambda-cyhalothrin (0.1 μg L−1) applied at two day intervals, each pulse lasting 90 min. Unexposed controls were included. We monitored macroinvertebrate taxonomic composition in the channels and in deployed leaf packs one day before and 29 days after the first exposure. Further, we measured drift in and out of the channels and leaf litter decomposition. Lambda-cyhalothrin exposures induced significantly increased drift in both experiments especially for Gammarus pulex, Amphinemura standfussi, and Leuctra spp. Macroinvertebrate taxonomic composition increasingly changed with increasing number of lambda-cyhalothrin exposures being most pronounced in the mesocosm channels. Further, leaf decomposition significantly decreased with increasing number of exposures in the mesocosm channels. Our study showed that species with predicted highest sensitivity to lambda-cyhalothrin were primary drivers of significant changes in taxonomic composition lasting for at least one month despite continuous recolonization of exposed channels from upstream parts of the natural stream and from the water inlet in the mesocosm channels. The overall results highlight the importance of sequential exposures to insecticides for understanding the full impact of insecticides on macroinvertebrates at the community level in streams. | acceptedVersion

Despite the large research effort on reporting quantities of coastal litter, the dynamics of this litter is not yet sufficiently understood. Litter inputs in five cobble beaches located in the Mediterranean (Spain) were studied over three months during winter by biweekly litter tagging. Plastic represented the dominant material that reached the beaches (77%). In remote and narrow beaches, storms constituted the main driver in litter dynamics, favouring the accumulation of floating items such as plastic bottles and wood fragments as well as the largest but contrasting effects, increasing litter inputs and outputs from the beach, respectively. In rural beaches, beach users, mainly fisher people, but also tourists, contributed to a notable input of litter to the beach. Burial and exhumation of litter were reported as common occurring processes. Better management actions are required to improve beach environmental quality. | This research is a contribution to the Andalusia PAI Research Group "RNM-328" and to the Ibero-American Beach Management and Certification Network -PROPLAYAS. This work was supported by the Biodiversity Foundation of the Ministry for the Ecological Transition and Demographic Challenge from Spain [FBIOMARINA19-01]. Special thanks go to David Saez, Natalia Sanchez, Laura Valero and Alba Amat for their help during the sampling periods and thanks to "Puertos del Estado" for oceanographic data. Thanks are also given to the municipalities involved in this research for answering to enquires about beach cleaning modalities. Finally, special thanks to two anonymous reviewers for their useful comments and suggestions, which have been very helpful in improving the manuscript.