In this study, the concentrations of 28 polychlorinated biphenyl (PCB) congeners, including 12 dioxin-like PCBs and 7 indicator PCBs, were determined in sediments around oil production facilities in the Escravos River Basin of the Niger Delta in Nigeria. The aim was to describe the spatial patterns, sources, and ecosystem risks associated with exposure to PCBs in sediments of this river basin. Gas chromatography-mass spectrometry (GC–MS) was used to determine the concentrations of PCBs in the sediments. The Ʃ28 PCB concentrations in sediments from the Escravos River Basin ranged between 226 and 31,900 ng g⁻¹ with a median concentration of 2300 ng g⁻¹. The results indicated that sediments around crude oil production facilities, such as, wellheads, flow stations, and truck lines, had significantly higher levels of Ʃ28 PCBs (p < 0.05) than those collected near residential communities within the river basin. The median concentrations of PCB homologues in sediments from this river basin followed the sequence: hexaPCBs > penta-PCBs > tetra-PCBs > hepta-PCBs > tri-PCBs > di-PCBs > deca-PCBs > octa-PCBs > nona-PCBs. The risk assessment of PCBs in sediments from this river basin suggest very high potential risks for both organisms and humans.

PURPOSE OF REVIEW: Beekeepers around the world have been reporting the ongoing weakening of honeybee health and subsequently the increasing colony losses since 1990. However, it was not until the abrupt emergence of colony collapse disorder (CCD) in the 2000s that has raised the concern of losing this important perennial pollinator. In this report, we provide a summary of the sub-lethal effects of pesticides, in particular of neonicotinoids, on pollinators’ health from papers published in peer-review journals. RECENT FINDINGS: We have identified peer-review papers that are relevant to examine the effects of sub-lethal pesticide exposures on the health of honeybees (Apis mellifera), bumblebees (Bombus terrestris), and other bees from a literature search on PubMed and Google Scholar using the following combined keywords of “pollinators,” “honeybee,” “bees,” “pesticides,” or “neonicotinoids,” and from a cross-reference check of a report made available by the European Parliament in preparation to fulfill their regulatory mandate on the issue of protecting pollinators among their membership nations. The weight-of-evidence of this review clearly demonstrated bees’ susceptibility to insecticides, in particular to neonicotinoids, and the synergistic effects to diseases that are commonly present in bee colonies. One important aspect of assessing and managing the risks posed by neonicotinoids to bees is the chronic effects induced by exposures at the sub-lethal levels. More than 90% of literature published after 2009 directly or indirectly demonstrated the adverse health effects associated with sub-lethal exposure to neonicotinoids, including abnormal foraging activities, impaired brood development, neurological or cognitive effects, and colony collapse disorder.

Plastics in Colombian marine-coastal ecosystems are being fragmented by various environmental factors, generating microplastics (size < 5 mm), an emerging pollutant that is ingested by marine organisms, representing a threat to ecosystems and potentially also to humans. This study aims to evaluate the incidence of microplastic ingestion by fishes from mangrove ecosystems in Cispata, Colombian Caribbean. The digestive tract content of 302 specimens of 22 fish species were analyzed using the KOH digestion method (500 g/5 L), stereoscopic visual identification and infrared spectroscopy. A total of 69 microplastics were found in the digestive tract of 7% of the analyzed fishes. 55% of the ingested microplastics were filaments, 23% fragments, 19% films, and 3% foam. The results of this study raised concerns about microplastic contamination in the marine environments, a threat to the fishery resource and to public health, which requires actions to prevent and reduce its negative effects.

A field study is presented that provides an alternative method and system for classifying the ecological quality status (EQS) of organically enriched marine sediments based on total free sulfide concentrations (S²⁻). Sediments collected adjacent to coastal aquaculture activities across a broad biogeographic range were analysed using three S²⁻ methods. S²⁻ is a product of organic matter mineralization and is a major cause of benthic community impacts from excess organic enrichment. The results confirm that the ion-selective electrode protocol that is widely used in monitoring programs to classify benthic impacts provides unreliable data and site classifications. An EQS classification system is presented that employs S²⁻ data measured rapidly and simply in the field by direct ultraviolet spectrophotometry. Interrelations between S²⁻ concentrations and several benthic macrofauna community health metrics were employed to develop the EQS system. These relationships were consistent regardless of organic matter source, geographic region or sediment grain size.

Phthalates, plastic-derived contaminants, are of increasing global concern. This study quantified phthalates in seabirds collected across >1700 km of the Aleutian Islands, Alaska, and contributes to a body of knowledge on plastic contaminants in marine wildlife. We measured six phthalate congeners in seabirds representing ten species and four feeding guilds. Phthalates were detected in 100% of specimens (n = 115), but varied among individuals (3.64–539.64 ng/g). DEHP and DBP occurred at an order of magnitude higher than other congeners. Total phthalates did not vary geographically, but differed among feeding guilds, with significantly higher concentrations in diving plankton-feeders compared to others. Plastic particles were detected in 36.5% of randomly subsampled seabird stomachs (n = 74), suggesting plastic ingestion as a potential route of phthalate exposure. Our findings suggest feeding behavior could influence exposure risk for seabirds and lend further evidence to the ubiquity of plastic pollutants in marine ecosystems.

The ecological quality status of the NE region of the Guanabara Bay (SE Brazil), one of the most important Brazilian embayments, is evaluated. For this purpose, sediment samples from in the inner of the Guanabara Bay (GB) were collected and analyzed (grain-size, mineralogy, geochemistry and living foraminifera). In this study, it is hypothesized that the potentially toxic elements (PTEs) concentrations, in solution and associated with organic matter (OMPTEs, potential nutrient source), may represent two potential pathways to impact benthic foraminifers. A multiproxy approach applied to complex statistical analyses and ecological indexes shows that the study area is, in general, eutrophic (with high organic matter and low oxygen content), polluted by PTEs and oil. As a consequence, foraminifera are not abundant and their assemblages are poorly diversified and dominated by some stress-tolerant species (i.e., Ammonia tepida, Quinqueloculina seminula, Cribroelphidium excavatum). The results allow us to identify a set of species sensitive to eutrophication and OMPTEs. Factors such as the increase of organic matter contents and OMPTEs and, in particular of Zn, Cd and Pb, the oxygen depletion and the presence of oil, altogether contribute to a marked reduction in the abundance and diversity of foraminifera. Ammonia-Elphidium Index and the Foram Stress Index confirm that the NE zone of GB is, in general, “heavily polluted”, with “poor ecological quality status” and experiences suboxic to anoxic conditions. In light of it, special attention from public authorities and policymakers is required in order to take immediate actions to enable its environmental recovery.

The pressing need to solve marine plastics pollution as a multi-source and multi-stakeholder problem is an ongoing global issue. This presents a challenge to policy makers tasked with understanding and accommodating different stakeholder perceptions and weighting their alternative propositions for solutions. In the case of Hong Kong, pollution of the marine environment by discarded plastics, polystyrenes and other items is a cumulative and accelerating problem that has yet to be resolved. We demonstrate how a geostatistical mapping approach can achieve joint stakeholder prioritization at any such regional scale. Joint prioritized area mapping is a methodology that links perspectives of otherwise disparate stakeholders to ecosystem-based-management, thereby balancing ecological, socio-economic and governance principles across temporal and spatial scales. It can serve as a generic scoping tool to help assess any marine spatial planning problem.

This study was concerned with spatial analysis of mercury (Hg) in sediment samples of the USA coastal areas using more accurate and stable hybrid approaches compared to the conventional methods. An ensemble of simulated annealing along with least angle regression (SA-LAR) was applied for selection of predictors in spatial analysis. The latest algorithm was efficient with resultant RMSE and R² of 0.066 and 0.705 compared to 0.099 and 0.571 for the traditional method of recursive feature elimination (RFE) approach. Using Cu, Pb and As as selected variables, it was tried to improve the spatial forecasting of Hg with either a hybrid of generalized boosted regression and ordinary kriging (GBROK) or inverse distance weighting (GBRIDW). According to the results, the variance explained by cross validation (VECV) was improved from 7.52% and 9.76% for IDW and OK to 40.41% and 41.94% for the GBRIDW and GBROK methods, respectively.

The aim of this study is to identify the environmental impact of drill cuttings (DC) released around three wells drilled in 1992, 2000 and 2012 in the SW Barents Sea. Foraminiferal assemblages are studied in cores taken along transects <250 m from wells. Well E-1992 shows no impact of DC on foraminifera indicating that low amounts of released DC limit environmental impact. Impact at wells G-2000 and S-2012, is confined to <30 m, and attributable to smothering of fauna, resulting in low foraminiferal density. We therefore argue that previous monitoring studies, mainly focusing on samples collected >250 m from wellheads, might not capture the full impact of DC. In well G-2000, a recovery layer indicates partial recovery 15 years after DC releases. In well S-2012, no recovery is observed, 3 years after release. Released DC did not result in faunal composition changes.

In this study, we conducted an experimental panel survey in Norway, Germany and Portugal to explore consumers' willingness to pay more for products that are certified microplastic free. This is placed within the context of private certification schemes and private governance as mechanisms to increase consumer conscientiousness, establish a higher environmental standard in terms of microplastic and reduce marine pollution. We find that consumers in general are very conscious about the issue, would generally prefer products that are microplastics free, but would seldom choose these when there is a price premium on the label. This had a geographical offset though, with the results aligning with that of political trust in the nation, with Norwegians being less likely to purchase items with price premiums for private governance labels, and Portugal being most likely to – even with a price premium.