This study evaluates the geographical distribution of Pb, Cd, Cr, Ni, Co, Cu, Zn, Mn and Fe in wild mussels Mytilus galloprovincialis as well as in associated suspended particulate matter (SPM) and sediments from the Algerian coast. The bioaccumulation (metal concentrations in tissue), bioavailability (metal indices) and bioconcentration of trace metals from the adjacent environment were assessed. The computed pollution load index (PLI) indicates that the sediments are not polluted by these metals, except for Zn which shows a moderate level of contamination. All the metals in SPM samples are in a ‘safe range’ with respect to the computed degree of contamination (DC < 2). The target hazard quotients (THQ) and the hazard index (HI) values indicate a risk level with Fe. However, the Cr measured in mussels is considered ‘extreme’, according to the consumption rate limit for mussels (CRₗᵢₘ) which limits their consumption to 0.5 kg/day.

PURPOSE OF REVIEW: Black carbon (BC) deposition in snow can trigger a significant reduction in snow albedo and accelerate snowmelt. As a result, numerous snow surveys have performed to measure BC concentrations in snow across the polar regions, the Tibetan Plateau, and other high-mountain regions. This review is aimed to synthesize the current progresses of the potential feedbacks of snow albedo and its sensitivity by BC in snow across the Northern Hemisphere. RECENT FINDINGS: Generally, BC concentrations in snow are highest in the mid-latitudes of Northern China and North America, and reduce toward higher latitudes (e.g., Greenland and the rest of the Arctic). We found that the snow albedo reduction attributed to low BC contamination (< 20 ng g⁻¹) in older snow (200 μm snow grains) is 1.2%, compared with 0.6% in fresh snow (50 μm snow grains). Non-spherical snow grains exhibit a significantly lower snow albedo reduction (2–6%) due to BC contamination compared with spherical snow grains with 100–500 ng g⁻¹ of BC in the snowpack. Snow–BC–internal mixing reduces the snow albedo (< 10%) more substantially than does external mixing in the case of 50–200 μm snow grains and a given BC concentration (< 2000 ng g⁻¹). Besides the BC and other light-absorbing particles (LAPs), the mixing state of LAPs in snow, snow grain properties, and the scavenging\washing effects are also major challenges in determining snow albedo, which need to be further investigated on a global scale.

Microplastic ingestion by intertidal fauna is a well-documented phenomenon, with emphasis on the physiological consequences of microplastic exposure. However, the behavioural effects of microplastic ingestion have not been explored to the same degree, even in species with documented microplastic ingestion. In this study, the predator-avoidance emergence response of Littorina littorea was assessed and related to microplastic levels within the samples. This is a novel approach to microplastic behavioural experiments, whereby current environmental L. littorea microplastic levels are assessed, rather than levels vastly in excess of those recorded under field conditions. The results showed no difference in emergence likelihood or emergence latency related to microplastic abundance, sex, or treatment. However, L. littorea size did have a significant effect on emergence likelihood and emergence latency, with smaller individuals emerging faster and more frequently. This study shows that microplastics, at their current environmental levels, do not seem to affect L. littorea emergence behaviour.

The water-soluble compounds of oil (e.g. low molecular weight PAHs) dissolve as a function of their physicochemical properties and environmental conditions, while the non-soluble compounds exist as dispersed droplets. Both the chemical and physical form of oil will affect the biological response. We present data from a mesocosm study comparing the microbial response to the water-soluble fraction (WSF), versus a water-accommodated fraction of oil (WAF), which contains both dispersed and dissolved oil components. WAF and WSF contained similar concentrations of low molecular weight PAHs, but concentrations of 4- and 5-ring PAHs were higher in WAF compared to WSF. Microbial communities were significantly different between WSF and WAF treatments, primary productivity was reduced more in WSF than in WAF, and concentrations of transparent exopolymeric particles were highest in WSF and lowest in the controls. These differences highlight the importance of dosing strategy for mesocosm and toxicity tests.

Triphenyltin (TPT) has been known as one of the most toxic compounds being released into the marine environment by anthropogenic means. This study assessed the contamination statuses of TPT and its two major degradants, i.e., monophenyltin and diphenyltin, in seawater, sediment and biota samples from marine environments of Hong Kong, a highly urbanized and densely populated city, and evaluated their ecological and human health risks. The results showed that the Hong Kong's marine environments were heavily contaminated with these chemicals, especially for TPT. Concentration ranges of TPT in seawater, sediment and biota samples were 3.8–11.7 ng/L, 71.8–91.7 ng/g d.w., and 9.6–1079.9 ng/g w.w., respectively. As reflected by high hazard quotients (1.7–5.3 for seawaters; 46.1–59.0 for sediments), TPT exhibited high ecological and human health risks. Our results are essential for the future management and control of anthropogenic TPT use in antifouling paints and as biocides in agriculture.

This paper presents a review around seagrass habitat in Tarawa Lagoon, Kiribati and explores the links between seagrass occurrence and the national priority issues of climate change, urban development, human health, nearshore fisheries, threatened species, ocean policy, research capacity and awareness. The contribution of healthy seagrass habitats to many aspects of these national issues is often overlooked and there is need to establish the knowledge gaps and priority actions that can enable mitigation of issues that impact on valuable seagrass resources and their management. Research data on seagrass habitats in Kiribati, and the wider Pacific Island region, is limited and this hinders informed decisions at local, national and regional levels. We present a comprehensive review on seagrass within a national context to aid prioritisation and uptake of information for resource owners, and wider stakeholders, in Kiribati while acknowledging local expertise. The paper highlights data and knowledge gaps that if addressed, will provide information useful to Kiribati nationals, communities and government stakeholders. Recommendations for actions that fill these gaps and build understanding of seagrass resources in Kiribati are provided.

Application of larvicidal oil (LO) is the most common practice in Hong Kong to control mosquitos, and hence prevent mosquito-borne diseases and protect human health. Globally, this study represented the first comprehensive assessment of toxicity and risk posed by LO to marine organisms. We found concentrations of LO ranged from 0.08 to 0.66 mg/L in coastal seawaters of Hong Kong. Waterborne exposure to water-accommodated fractions of LO resulted in growth inhibition to two microalgal species (72-h EC₅₀: 1.92–2.90 mg/L) and acute mortality to three marine animals (96-h LC₅₀: 3.41–8.10 mg/L). From these toxicity results, a concentration that considered to be hazardous to 5% of species (HC₅) was predicted at 1.45 mg/L, while the predicted no-effect concentration was determined to be 0.29 mg/L. The hazard quotient of LO exceeded 1 at 9 out of 15 sites, indicating moderate-to-high ecological risk to exposure of LO in the marine environment of Hong Kong.

The original version of this article, unfortunately, contained an error. In the recently published paper, “Health Effects of Climate Change Through Temperature and Air Pollution,” there was an error in the first paragraph of the Introduction.

Profiling bathing waters supported by Quantitative Microbial Risk Assessment (QMRA) is key to the WHO's recommendations for the 2020/2021 revision of the European Bathing Water Directive. We developed an area-specific QMRA model on four pathogens, using fecal indicator concentrations (E. coli, enterococci) for calculating pathogen loads. The predominance of illness was found to be attributable to Human Adenovirus, followed by Salmonella, Vibrio, and Norovirus. Overall, the cumulative illness risk showed a median of around 1 case/10000 exposures. The risk estimates were strongly influenced by the indicators that were used, suggesting the need for a more detailed investigation of the different sources of fecal contamination. Area-specific threshold values for fecal indicators were estimated on a risk-basis by modelling the cumulative risk against E. coli and enterococci concentrations. To improve bathing waters assessment, we suggest considering source apportionment, locally estimating of pathogen/indicator ratios, and calculating site-specific indicators thresholds based on risk assessment.

Currently, microplastics are a major challenge threatening marine environment. Given little information on their prevalence in the Persian Gulf, the present study as the first comprehensive study was conducted to evaluate microplastics abundance in surface waters. Neustonic samples were collected from 15 stations along the Persian Gulf. Visually separated microplastics were categorized according to their size, shape, and color. ATR-FTIR method was used to identify the composition of polymers. Microplastics were found in all sampling stations and their density varied from 1.5 × 10³ to 4.6 × 10⁴ particle.km⁻² with a mean density of 1.8 × 10⁴ particle.km⁻². Fibers were the most dominant shape of microplastics (44.1%). Approximately 76% of the analyzed microplastics were polyethylene and polypropylene and the predominant colors of the microplastics were white and blue. Results of the study confirmed prevalence of microplastics in the Persian Gulf, and findings suggested a pressing need to investigate their effects on marine life and human health.