Monitoring of current-use pesticides along a Europe-Arctic transect using ships of opportunity.

Understanding the occurrence and fate of current-use pesticides (CUPs) in coastal and open marine waters is essential for conducting exposure and risk assessments to ensure the protection of marine ecosystems from chemical pollution. While CUPs have been frequently studied in freshwater systems, knowledge of their behavior in marine environments remains fragmentary. This study investigated 28 CUPs across 50 sites along a transect from the Baltic outflow to pristine Arctic waters using ships of opportunity with installed FerryBox system. Overall, 14 CUPs were detected at least at one site at concentrations ranging from sub-ng/L to ng/L. CUP concentrations were higher in the Baltic outflow and decreased along the transect. Atrazine, simazine, tebuconazole, and propiconazole were detected in > 40 % of samples, including remote open sea regions, suggesting their potential for long-range marine transport. This Baltic Sea was identified as a major source of CUPs to connected marine systems. Additional CUPs were detected in the Baltic outflow, encompassing diuron, isoproturon, metazachlor, metolachlor, pyrazon, terbuthylazine, and chlortoluron. Ecotoxicological assessment indicated a moderate risk posed by metolachlor to algae. The use of the described infrastructure holds great promise for advancing our understanding of the occurrence and fate of CUPs in marine environments.

Effect-directed analysis to explore the polar bear exposome: identification of thyroid hormone disrupting compounds in plasma.

Compounds with transthyretin (TTR)-binding potency in the blood plasma of polar bear cubs were identified with effect-directed analysis (EDA). This approach contributes to the understanding of the thyroid disrupting exposome of polar bears. The selection of these samples for in-depth EDA was based on the difference between the observed TTR-binding potency on the one hand and the calculated potency (based on known concentrations of TTR-binding compounds and their relative potencies) on the other. A library-based identification was applied to the liquid chromatography-time-of-flight-mass spectrometry (LC-ToF-MS) data by screening for matches between compound lists and the LC-ToF-MS data regarding accurate mass and isotope pattern. Then, isotope cluster analysis (ICA) was applied to the LC-ToF-MS data allowing specific screening for halogen isotope patterns. The presence of linear and branched nonylphenol (NP) was observed for the first time in polar bears. Furthermore, the presence of one di- and two monohydroxylated octachlorinated biphenyls (octaCBs) was revealed in the extracts. Linear and branched NP, 4'-OH-CB201 and 4,4'-OH-CB202 could be successfully confirmed with respect to their retention time in the analytical system. In addition, branched NP, mono- and dihydroxylated-octaCBs showed TTR-binding potencies and could explain another 32 ± 2% of the total measured activities in the extracts.

First report of chlorinated and brominated hydrocarbon pollutants in marine bird eggs from an oceanic Indian Ocean island.

We report for the first time levels of persistent organic pollutants in marine bird eggs from an oceanic island in the Indian Ocean, the world's third largest ocean. Ten eggs each of the Common Noddy, also known as the Brown Noddy (Anous stolidus), and Sooty Tern (Sterna fuscata) were collected from Ile Cocos off the coast of the island of Rodrigues, located 560 km east of the island of Mauritius. ΣPCBs had the highest levels (2.2 and 2.6n g/g wm, wet mass; 20 and 19 ng/g lm, lipid mass) for common Noddy and Sooty Tern, respectively (and following), then ΣDDT (1.9 and 3.1 ng/g wm; 17 and 23 ng/g lm), and mirex (0.96 and 0.69 ng/g wm; 8.7 and 5.0 ng/gl m). ΣChlordanes (0.094 and 0.15 ng/g wm; 0.48 and 0.73 ng/g lm) and Σtoxaphenes (0.26 and 0.61 ng/g wm; 2.4 and 5.9 ng/g lm) are rare data for these compounds from this ocean. Brominated flame retardants were low (0.08 and 0.07 ng/g wm; 0.7 and 0.7 ng/g lm). Multivariate analyses indicated different contamination patterns in the prey items as Sooty Terns had significantly higher levels of mean Σchlordanes and Σtoxaphenes, as well as CB105, -108 and -157. p,p'-DDE had an association with thinner eggshells in the Sooty Tern. Although the contaminant levels were in all respects low, industrialisation, development on the periphery, commercial exploitation of the marine environment, and pollutants transferred over long distances by marine debris is likely to add to chemical pressure in this region. Monitoring changes in background levels of pollutants in remote regions will indicate such trends, and marine bird eggs from Rodrigues would be an excellent site.

Line ferries and cargo ships for the monitoring of marine contaminants of emerging concern: Application along a Europe-Arctic transect.

Contaminants of emerging concern (CEC) are a focus in marine protection. Several CECs are released with wastewater effluents to coastal environments and their offshore occurrence has been recently documented. Routine monitoring is key for implementing marine protection acts, however infrastructural, financial, and technical limitations hinder this task along broad spatial transects. Here we show the efficacy of a new infrastructure enabling unmanned sampling of surface water from ships of opportunity in providing reliable and cost-effective routine monitoring of CECs along a Europe-Arctic transect. The distribution and long-range transport of several pharmaceuticals and personal care products, artificial food additives, and stimulants were assessed. Validation of operations through strict procedural and analytical quality criteria is presented. A framework to estimate a compound-specific spatial range (SR) index of marine long-range transport based on monitoring results and information on source spatial distribution, is introduced. Estimated SR values ranged 50-350 km depending on compound, yielding a ranking of long-range transport potential which reflected expectations based on degradation half-lives. SR values were used to calculate prior maps of detection probability that can be used to plan future routine monitoring in the region.

Performance of Three-Dimensional Rainbow Trout (Oncorhynchus mykiss) Hepatocyte Spheroids for Evaluating Biotransformation of Pyrene.

The aquatic bioconcentration of a chemical is typically determined using conventional fish tests. To foster the approach of alternatives to animal testing, a combination of computational models and in vitro substrate depletion bioassays (e.g., primary hepatocytes) can be used. One recently developed in vitro assay is the three-dimensional (3D) hepatic spheroid model from rainbow trout (Oncorhynchus mykiss). The aim of the present study was to evaluate the metabolic competence of the 3D spheroids from rainbow trout when exposed to pyrene, using 2 different sampling procedures (SP1 and SP2). The results were compared with previously published intrinsic clearance (CL) results from S9 fractions and primary hepatocyte assays. Extraction of pyrene using SP1 suggested that the spheroids had depleted 33% of the pyrene within 4 h of exposure, reducing to 91% after 30 h. However, when applying SP2 a substantial amount (36%) of the pyrene was bound to the exposure vial within 2 h, decreasing after 6 h of exposure. Formation of hydroxypyrene-glucuronide (OH-PYR-Glu) was obtained throughout the study, displaying the metabolic competence of the 3D spheroids. The 2 sampling procedures yielded different CLin vitro , where pyrene depletion using SP2 was very similar to published studies using primary hepatocytes. The 3D spheroids demonstrated reproducibile, log-linear biotransformation of pyrene and displayed formation of OH-PYR-Glu, indicating their metabolic competence for 30 h or more. Environ Toxicol Chem 2019;38:1738-1747. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

Balsa raft crossing the Pacific finds low contaminant levels.

During the Norwegian Tangaroa balsa raft expedition crossing the Pacific in 2006, surface water samples were collected by passive semipermeable membrane device (SPMD) sampling, active surface microlayer collection, and fish bile collection. The samples were analyzed for water contamination including a range of persistent organochlorine contaminants, pesticides, polycyclic aromatic hydrocarbons, as well as modern widespread chemicals such as brominated flame retardants, UV-filters, and perfluorinated compounds, using a network of expert laboratories and advanced instrumentation. Only trace to undetectable levels of all compounds were observed in both SPMDs and microlayer samples. The data from SPMDs were used to estimate surface water concentrations by back-calculation using sampling rates published in the literature. Conservative factors indicate that the levels in the surface waters are in the pg/L to subpg/L range for organochlorines, BFRs, and PFCs, indicating the central Pacific Ocean still represents a pristine environment for oceanic life.