Harbours are located in major urban centres around the world and are of great economic importance to the cities in their surroundings. However, the intense traffic of boats and ships can generate environmental impacts that can directly affect the local biota as well as the population that lives in surrounding areas. Therefore, this work aimed to analyse the surface sediment of the Niterói Harbour using chemical, biological and micropalaeontological tools to investigate the environmental condition of this important harbour in Rio de Janeiro State. The pseudototal trace metal data analysed in the surface samples showed values far above those of the greater Guanabara Bay background. These data were corroborated by a high mortality rate of Artemia sp. and elevated presence of the bacterium Vibrio fischeri, indicating a high rate of local pollution. Dinoflagellate cysts also showed a direct response to high values of pseudototal trace metals. The data obtained in this study emphasize a need for greater monitoring of ports since the experience gained through this study in a Brazilian harbour can serve as an example for the management of other harbours located in large urban centres around the world.

During the COVID-19 pandemic, disposable surgical masks were generally disinfected and reused due to mask shortages. Herein, the role of disinfected masks as a source of microplastics (MPs) and nanoplastics (NPs) was investigated. The amount of MPs and NPs released from masks disinfected by UV ranged from 1054 ± 106 to 2472 ± 70 and from 2.55 ± 0.22 × 10⁹ to 6.72 ± 0.27 × 10⁹ particles/piece, respectively, comparable to that of the undisinfected masks, and the MPs were changed to small-sized particles. The amount of MPs and NPs released after alcohol and steam treatment were respectively lower and higher than those from undisinfected masks, and MPs were shifted to small-sized particles. The amount of MPs and NPs released in water after autoclaving was lower than for undisinfected masks. In all, the amount of fibers released after disinfection decreased greatly, and certain disinfection processes were found to increase the amount of small-sized NPs released from masks into aqueous environments.

The present report provides data on entanglement of Steller sea lions (SSL) in marine debris on Tyuleniy Island, Sea of Okhotsk. The frequency of entanglement depending on the material, sex, and age of animals was estimated. A total of 133 SSL were recorded as having debris on their bodies, or an average of 22.2 individuals per year. The relative rate of entanglement over the observation years ranged from 1.48 to 1.97% of their total number. The entangled individuals were both males and females of all ages, but young males constituted the largest proportion among them (5.2%). The entangled SSL most frequently (43.2%) had neck collars (the material is not defined) and, less frequently, packaging bands (23.4%), nets (17.7%), and other debris. Most of marine litter found on SSL is associated with commercial fishing activities. On Tyuleniy Island, the rate of SSL entanglement is higher than in the eastern part of the species' range.

The Caribbean Sea is reported to have one of the highest levels of plastic pollution of any marine ecosystem. Much less is known about the levels of microplastics as an emerging pollutant in the marine environment, especially in the water column and benthic substrates where they can be easily ingested by marine organisms. This study was carried out to quantify marine microplastics in the Wider Caribbean using the mollusk, queen conch (Aliger gigas). We analyzed feces collected from queen conch, a non-lethal method of sampling, to investigate microplastic pollution in eleven sites across the Wider Caribbean. Microplastics were extracted by degradation of organic matter from feces with peroxide (30%) over 48 h. Microplastics were then analyzed by stereomicroscope and scanning electron microscope. Microplastics were found to be present in the feces of all 175 queen conch sampled, and in statistically different abundances among sites, but with no obvious geographical pattern. The highest and lowest levels were found in Central America; the highest being in Belize (270 ± 55 microplastics/queen conch) and Alacranes, Mexico (203 ± 29 microplastics/queen conch), whilst the lowest levels were found in Puerto Morelos, Mexico. Fibers, mostly between 1000 and 1500 μm in size, were the most frequent microplastic particle types at every site and represented between 60 and 98% of all microplastic particles found. Our results suggest that the use of queen conch feces is a suitable method for detecting benthic microplastic pollution, and have confirmed that microplastic pollution of marine benthos is widespread across the Wider Caribbean.

This study provides information on the current situation of microplastics contamination in inland freshwater bodies in Vietnam. An urban drainage channel in Da Nang City was selected as a case study. Receiving mainly domestic wastewater and landfill leachate, the channel itself is becoming a microplastic pollution hotspot with a microplastic concentration of 1482.0 ± 1060.4 items m⁻³ in waters and 6120.0 ± 2145.7 items kg⁻¹ in sediments. The dominant shapes of microplastics were fibers and fragments, in which the polymer types were mainly polyethylene, polypropylene, and polyethylene terephthalate. Microplastics with sizes ranging from 1000 to 5000 μm tended to be distributed primarily in surface waters, whereas particles from 300 to 1000 μm accumulated in sediments. The channel places Da Nang Bay at a high risk for microplastic pollution, with an estimated pollution load of approximately 623 × 10⁶ items d⁻¹ in dry weather.

Sewage is one of the biggest contributors to coastal pollution. The study was aimed to assess the impact of sewage on coastal water quality of Kanyakumari, the southernmost part of India. A bacteriological survey was made on distribution and abundance of fecal indicators and human pathogenic bacteria and seasonal influence on the bacterial load and antibiotic resistance of the isolates. Samples were collected from sewage discharge point along the eastern shore of Kanyakumari Coast from February 2019 to January 2020. Nine pollution indicator bacteria and pathogenic species such as Escherichia coli, Klebsiella spp., Enterococcus faecalis, Aeromonas spp., Proteus mirabilis, Salmonella typhi, Vibrio cholerae, Shigella spp. and Flavobacterium spp. were isolated from the samples. These isolates were tested against 10 antibiotics, using Kirby Bauer method. All the isolates were resistant to at least two antibiotics. The presence of antibiotic resistant bacteria has been used as bio-indicators of pollution. Hence it is clear that the domestic sewage entering the coast is untreated which might lead a serious impact on human and marine wildlife along coastlines.

The Gulf contains important biodiversity, but is also heavily impacted. While studies have measured seawater contaminants and toxicity, we are not aware of discrete sampling of the sea surface microlayer (SML). This ocean-atmosphere interface is important environmentally, but also sensitive to marine and atmospheric contaminant inputs. We sampled the SML and subsurface seawater (SSW) from the Gulf in August 1991 and 1992. The SML exhibited significant enrichment of petroleum hydrocarbons, Cu, Cd and Pb, which persisted more than one year after the massive 1991 Gulf War oil spill. Toxicity to echinoderm larvae was also greater in the SML. This likely reflects effects of contaminants measured and other stressors. Sophisticated techniques used over recent decades to determine biological effects of contaminants in the Gulf could usefully extend to the SML. Our study has demonstrated its sensitivity and could serve as a ‘baseline’ for determining long-term persistence of seawater contamination and toxicity.

This study assessed the seasonal variation in the magnitude of marine litter along the Gulf of Guinea coastline, Araromi seaside, Nigeria with a survey of twenty sampling sites. The total number of litter items collected was 29,029 comprising 7358 and 21,671 items in the dry and rainy season respectively. The average number of items per square meter was higher in the rainy season (1.80 ± 0.35) than in the dry season (0.61 ± 0.19). Plastic materials dominated the litter composition with 86 % and 91.8 % in the dry and rainy season respectively. The beach cleanliness assessed as clean coast index (CCI) depicted the beach as dirty (12.26 ± 3.74) during the dry season and extremely dirty (36.13 ± 6.91) in the rainy season. The hazardous item index (HII) also showed the coastline was littered with hazardous items. These results provide baseline data for marine litter management along the Gulf of Guinea coastlines and other coastlines in Africa.

The Florida Everglades is a unique and fragile coastal wetland ecosystem that is undergoing a decades-long, large-scale ecological restoration. This freshwater ecosystem in southern Florida has been stressed by diminishment of freshwater flow and water diversion due to agricultural activities and urbanization. The health of this vast ecosystem is also threatened by the presence of a large number of invasive species, including the Burmese python. These large constrictors were introduced to South Florida through the pet trade; first sightings in Everglades National Park occurred in the 1980s. Pythons are naturally camouflaged in the Everglades, which turns out to be an excellent environment for propagation of these huge predators. This top predator has severely disrupted the food web, consuming mammals, birds and even other reptiles. In this paper, the current population control efforts implemented by various management agencies are assessed. While more paid professional hunters should be retained to join the search and removal efforts, innovative control measures are necessary.