This paper examines which demographic and attitudinal characteristics relate to an individual's knowledge and perception of the environmental footprint of single-use mask s/he is using in the midst of the COVID-19 pandemic. Based on a self-selected sample of Greek citizens (N = 462), it is found that demographic characteristics and pro-environmental concern are unrelated to the single-use mask users' knowledge and concern regarding the environmental impacts of the mask they are using. This unanticipated finding suggests that the circumstances of the COVID pandemic may mute the theoretically taken-for-granted connection between environmental interest/concern and the awareness of environmental impacts, thus any future attempts to introduce more environmentally-friendly single-use mask alternatives and/or to curb the current ones' environmental impact should start by reenergizing this suppressed nexus.

Microplastic pollution has received substantial international attention in terrestrial and marine environments and in the atmosphere. In this study, we assessed microplastic pollution and analyzed the accumulation of microplastics in the gills of fish caught in the Zhoushan fishing ground from September 2017 to March 2018. The average abundance of microplastics was 0.49 ± 0.54 particles/gill and frequently found chemical polymers was polyethylene terephthalate. We also conducted experiments on microplastic pollution in the water and the working solutions used during the analytical process and found that the source of microplastic contamination was the solutions used. Moreover, we evaluated and scored experimental quality control and quality assurance adapted from the ‘Total Accumulated Score’ method. Valuable steps are recommended in order to produce reliable results and improve the quality of results in microplastic analyses.

Heavy metal concentrations in deep-sea sediments collected from Kuril Basin (Sea of Okhotsk) and Kuril-Kamchatka Trench area were analyzed. For the Kuril Basin, a geochemical natural background of these elements was identified based on a dated core. The results showed enrichment by heavy metals due to natural factors in the study area. All heavy metals showed a low ecological risk; thus, the potential ecological risk of the study area was also low.

Mercury has been measured by using Cold Vapor-Atomic Absorption Spectrophotometry in coastal sediments of the Persian Gulf (Bandar Abbas region). The mean concentration of the six stations followed a decreasing order of S6 (3.95) > S1 (3.75) > S4 (3.55) > S5 (3.33) > S2 (2.72) > S3 (2.17), and the mean concentration ± standard error was calculated to be 3.24 ± 0.28 (μgg⁻¹ dry weight) for the heavy element Mercury in the sediments. The statistical investigation indicated that the concentration means of the Mercury existing in transects sediments are meaningfully different from each other (p < 0.05). To properly assess the availability and mobility of elements, Enrichment Factor (EF), Geoaccumulation index (Igeo), Contamination factor (Cf) and Toxicity Risk Index (TRI) were provided. The results show that the pollution caused by Mercury in sediments is highly polluted and the source of the presence of Mercury in the region is human-made.

The Brazilian oil spill, from August 2019 to January 2020, was considered the most extensive accident in tropical oceans. We estimated the concentration of oil droplets that may be available for ingestion by microzooplankton. The collection was carried out in three areas: estuarine plume, bay and reef (Tamandaré, Pernambuco coast). We highlight the contribution of coral larvae in the reef region, surpassing the copepods, evidencing a spawning event. Oil droplets were recorded in all the sampled areas, with a high numerical abundance in the plume. Traces of oil ingestion by Brachyura zoea and Calanoida, Paracalanidae and Oithonidae copepods were observed, suggesting that these groups might have an important role in the degradation and final destination of oil dispersed after spills. The vulnerability of the larval phases of crabs and reef-building corals has been hypothesized, suggesting that the negative effects of oil on zooplankton can affect the recruitment of benthic invertebrates.

A large-scale oil spill has reached over 3000 km of the NE Brazilian coast since August 2019. The cause and origin of this spill remain mysterious, and the impacts on coastal ecosystems have not been clearly understood so far. Despite the efforts to remove the oil (mainly from local communities), oil stains are still present in beaches, mangroves, and beachrocks. In this short report, we describe the occurrence of the barnacle Chthamalus bisinuatus Pilsbry, 1916 colonizing oil spill stains on intertidal surfaces of beachrocks one year after the first oil records. We quickly assessed oil stains across three different reefs located at the Conde municipality, Bahia (NE Brazil), where the species was identified and its density on oil stains calculated. The occurrence of barnacles in oil stains was restricted to zones in the wake of the reefs. Their densities varied from 0 to 238 ind./dm², with an average of 34 ± 68 ind./dm². If we account for dead individuals (empty barnacle plates), they correspond to 25.9% of the sampled population. The presence of oil possibly affected barnacle survival rates but did not seem to prevent barnacle individuals from reaching adult sizes. We also found individuals of the snail Echinolittorina lineolata (d'Orbigny, 1840) crawling on these barnacles, indicating that the barnacle assemblages on oil stains are stable enough to provide refuge for these snails. It is not clear if the presence of barnacles on oil reflects the resistance of these crustaceans to the oil toxicity or is just a result of a low substrate selectivity by the cypris larvae.

Cigarette filters are made of non-biodegradable plastic and are one of the top littered items worldwide. Here, we determine if policy implementation is an effective strategy for reducing cigarette filter litter on beaches in Maui, Hawai'i by comparing cigarette filter counts before and after a policy banning tobacco use was implemented. We use a before–after control–impact (BACI) design to investigate whether changes in cigarette filter accumulation at an impact site, where tobacco use was banned, decreased relative to counts at a control site, where tobacco use was not banned. A total of 764 cigarette filters were removed with no significant difference detected in cigarette filter littering between the control and impact site after the policy went into place. This study shows that policy requiring a shift from social norms, such as tossing cigarette butts, needs to be accompanied by sustained law enforcement and awareness around the policy to be effective.

The development of desalination has been essential to the rapid economic development of the countries bordering the Arabian Gulf. The current production capacity of sea water desalination plants drawing water from Gulf is over 20 million m³ day⁻¹, which may rise to 80 million m³ day⁻¹ by 2050. Whilst supporting aspects of sustainable development related to water and sanitation, desalination impacts the marine environment through impingement and entrainment of organisms in intakes, and through thermal, brine and chemical discharges. This may compromise other objectives for sustainable development related to sustainable use of the oceans. Under business as usual scenarios, by 2050, the impact of individual desalination plants will combine causing a regional scale impact. Without mitigating actions to avoid the business as usual scenario, by 2050, desalination in combination with climate change, will elevate coastal water temperatures across more than 50% of the Gulf by at least 3 °C, and a volume of water equivalent to more than a third of the total volume of water between 0 and 10 m deep will pass through desalination plants each year. This will adversely impact the coastal ecosystem of the Gulf, with impacts on biodiversity, fisheries and coastal communities and may cause potential loss of species and habitats from the Gulf. Given the significant implications of these preliminary findings, and in light of the precautionary approach to management, it is recommended that mitigating options addressing behavioural, regulatory and technological change are rapidly evaluated and implemented to avoid the development of desalination in the region along a business as usual pathway, and multidisciplinary research studies should be conducted to reduce uncertainty in predictions of future impacts.

The present pilot study aimed to provide an overview of organic contaminant concentration levels in the littoral ecosystems of the Pertuis seas. The study determined the concentrations of twenty-nine pesticides, six nonylphenols and seven polybrominated diphenyl ethers (PBDEs) in sediments, seawater, Pacific oysters and blue mussels. Oysters accumulated a higher number of pesticides than blue mussels. Indeed, alpha BHC (0.60–0.72 ng/g, ww), chlorfenvinphos (1.65–2.12 ng/g, ww), chlorpyrifos (0.79–0.93 ng/g, ww), chlortoluron (2.50–4.31 ng/g, ww), metolachlor (up to 0.38 ng/g, ww) and parathion (0.56–0.69 ng/g, ww) were quantified in oysters whereas only alpha BHC (0.24–0.31 ng/g, ww), was quantified in mussels. The present results also revealed that the POPs detected in water or sediments were not ultimately found accumulated in bivalves. Other molecules such as methylparathion and BDE47 were quantified in sediments. These molecules, BDE99 and one nonylphenol (OP2OE) were quantified in seawater. Finally, the comparison with the available environmental guidelines showed that the values measured were at concentrations not considered to cause adverse effects at the populations' level except for chlortoluron in seawater (15–50 ng/L).

Intertidal microbial communities occur as biofilms or microphytobenthos (MPB) which are sediment-attached assemblages of bacteria, protozoa, fungi, algae, diatoms embedded in extracellular polymeric substances. Despite their global occurrence, they have not been reviewed in light of their structural and functional characteristics. This paper reviews the importance of such microbial communities and their importance in carbon dioxide sequestration as well as pollutant bioremediation. Global annual benthic microalgal productivity was 500 million tons of carbon, 50% of which contributed towards the autochthonous carbon fixation in the estuaries. Primary production by MPB was 27–234 gCm⁻²y⁻¹ in the estuaries of Asia, Europe and the United States. Mechanisms of heavy metal removal remain to be tested in intertidal communities. Cyanobacteria facilitate hydrocarbon degradation in intertidal biofilms and microbial mats by supporting the associated sulfate-reducing bacteria and aerobic heterotrophs. Physiological cooperation between the microorganisms in intertidal communities imparts enhanced ability to utilize polycyclic aromatic hydrocarbon pollutants by these microorganisms than mono-species communities. Future research may be focused on biochemical characteristics of intertidal mats and biofilms, pollutant-microbial interactions and ecosystem influences.