Marine plastic debris can act as a reservoir of chemical additives that can pose a potential threat to sensitive ecosystems such as coral reefs. A survey of foam macrodebris collected on beaches indeed revealed high concentrations of hexabromocyclododecanes (ΣHBCDD) in polystyrene (PS) samples (up to 1940 μg g⁻¹). Results also showed that PS fragments can still leach over 150 ng g⁻¹ d⁻¹ of ΣHBCDD (primarily as the α-isomer) for relatively long durations, and that these additives are readily bioaccumulated and well-retained by corals. Despite significant HBCDD bioaccumulation in coral tissue, short-term exposure to HBCDD or PS leachate had no considerable effect on coral photosynthetic activity, symbiont concentration and chlorophyll content. Exposure to the PS leachate did however cause consistent polyp retraction in nubbins over the 5-day exposure. This response was not observed in animals exposed to HBCDD alone, suggesting that another constituent of the leachate stressed corals.

Marine litter is a world-wide problem, but the knowledge on this topic in remote areas such as the poles and the deep-sea is still limited. This paper seeks to provide the first accounts of deep-sea litter in the South-Western Caribbean Sea. The survey used 5066 still images from ROV video surveys around four hydrocarbon exploratory drilling zones. Forty-eight deep-sea litter items were found at depths between 427 and 2561 m, and analyzed by three different marine litter classifications. Plastic was the most frequent material (65%) and general litter the main category (69%). Almost half of the deep-sea litter items were found close to marine organism. This baseline is a first step to further research of human impact on the marine bottoms of the Caribbean. The paper highlights the importance of deep-sea litter as a descriptor of marine pollution, and the role of scientific cooperation between off-shore industry and the academy.

Tubastraea coccinea Lesson, 1830 and T. tagusensis Wells 1982 are azooxanthellate corals non-native to Brazil and introduced through fouling on oil platforms, the primary vector. They first invaded the tropical rocky reefs at Ilha Grande Bay (southwest Atlantic Ocean), during the early 1990s. Currently, at some Brazilian locations these species occupy 80% of the benthos of the shallow subtidal. They cause economic and environmental impacts by fouling shipping and modifying native communities. This study provides observations of an additional mechanism of secondary dispersal by T. coccinea and T. tagusensis that were seen attached to floating wood debris and marine litter, which are highly abundant in the region. Such rafting corals have been found adjacent to invaded reefs and stranded on beaches. These observations indicate that transport by rafting over long distances may be another mechanism of range expansion and secondary introduction of these invasive species within the region.

Environmental changes and anthropogenic activities can be linked to altered distribution and abundance of species. However, the ecological impacts of change in the microenvironment have not been well documented. Herein, we have identified the distribution of mangroves and associated species and characterized surface sediment and water samples along the banks of River Hooghly. The application of Combined Mangrove Recognition Index (CMRI) and its validation with the available ground data on satellite image of 2015 indicates that some mangrove species have reclaimed the upper course of the river, which was earlier absent before 1995. This study is the first report on the upstream migration of mangrove species such as Sonneratia caseolaris, Sonneratia apetala, Derris trifoliata, Hibiscus tiliaceus, and Thespesia populnea in River Hooghly. The changes in pollution load, varied sedimentation pattern, high chemical oxygen demand, mean sea-level rise, and anthropogenic activity might have played a significant role in the upstream migration of mangroves.

BACKGROUND: Air pollution is a global problem with PM₂.₅ being one of the major pollutants causing many diseases. The concentrations of PM₂.₅ are found to exceed the World Health Organization (WHO) standards especially in lower middle-income countries (LMICs) that house around 40% of the global population. MATERIALS AND METHODS: Studies conducted globally in the past 5 years (2015–2019) on health effects of PM2.5 were systematically reviewed to understand the current research gaps. For this systematic search, Web of Science and PubMed were used to obtain 247 articles. RESULTS: Systematic review of these studies revealed that PM₂.₅ and other air pollutants have been found to be associated with increased mortality and morbidity due to respiratory, cardiovascular, cerebrovascular disorders and diabetes. However, most of the total studies (~ 69%) were carried out in the high-income countries (HICs) despite the fact that PM₂.₅ concentrations are higher in the LMICs (annual mean exposure (2011–2017) of 48.42 µg/m³) and lower in the HICs (annual mean exposure (2011–2017) of 20.02 µg/m³). Therefore, the exposure response functions for mortality estimates associated with PM₂.₅ and developed using the exposure data from the HICs will not have predictive value in the LMICs. Furthermore, very few studies relate chemical components and source apportionment of PM₂.₅ to the associated toxicity. CONCLUSIONS: More studies on morbidity and mortality associated with PM2.5 and its components are needed in LMICs for better estimation of the overall risks.

PROPOSE OF REVIEW: Anthropogenic activities are saturating wastewater treatment plants and the environment with an increasing range of organic and inorganic compounds, impairing ecosystems and health. Filamentous fungi, with characteristic filamentous growth, array of extracellular and intracellular enzymes, production of surfactants, cell wall biosorption properties, and symbiotic momentum, can contribute to a paradigm shift on the perception of anthropogenic pollution. This review provides a critical analysis of the main bottlenecks for feasible filamentous fungus-including processes and proposes a holistic approach for pollution mitigation using filamentous fungi. RECENT FINDINGS: Filamentous fungi can convert ordinary sidestreams into, e.g., feed proteins and biofuels. Economic and environmental studies support integration in established processes. Intersectoral initiatives, and economic and environmental studies, need to be motivated to increase the range of processes. Although massively studied, the transfer of fungal processes for the removal of micropollutants into real matrices is difficult. It needs to be supported by omics technologies for the study of microbial networks, and by efficient analytical techniques to clarify detoxification potential. The area can benefit from knowledge integration from fungal growth in ordinary sidestreams, and from economic and environmental studies. The interest in filamentous fungi for pollution mitigation is corroborated by an overwhelming amount of research; however, no full-scale applications are currently known. Environmental pollution is a reality and production of ordinary sidestreams and micropollutant-rich wastewaters continuous. The establishment of filamentous fungal processes needs collaboration among governmental authorities, industries, and academics in order to tackle knowledge gaps within the area and propose a holistic approach.

Prevalence of SARS-CoV-2 in the aquatic environment pertaining to the COVID-19 pandemic has been a global concern. Though SARS-CoV-2 is known as a respiratory virus, its detection in faecal matter and wastewater demonstrates its enteric involvement resulting in vulnerable aquatic environment. Here, we provide the latest updates on wastewater-based epidemiology, which is gaining interest in the current situation as a unique tool of surveillance and monitoring of the disease. Transport pathways with its migration through wastewater to surface and subsurface waters, probability of infectivity and ways of inactivation of SARS-CoV-2 are discussed in detail. Epidemiological models, especially compartmental projections, have been explained with an emphasis on its limitation and the assumptions on which the future predictions of disease propagation are based. Besides, this review covers various predictive models to track and project disease spread in the future and gives an insight into the probability of a future outbreak of the disease.

Pygmy sperm whales, Kogia breviceps (Kogiidae), are a small cetacean that inhabits Mesopelagic regions near the continental shelf. In this study we present record of plastic ingestion by K. breviceps in Brazil. In August 2010 on the coast of Rio Grande do Sul, a carcass was found showing evidences of interaction with fishing nets. The stomach content was collected for the analysis of food items, but the presence of four plastics weighing 55.9 g was found. In addition, the analysis of food items revealed the presence of the fish Merluccius hubbsi, which is an intensely explored species by fisheries activities in southern Brazil. Merluccius sp. is common in the diet of K. breviceps in several regions of the planet. This work shows that in southern Brazil, K. breviceps suffers intense impact of both ingestion of anthropic material and fisheries, and so must be closely monitored.

Understanding the faunal community structure in the estuary would be crucial in assessing the health of the ecosystem. The poor visibility in the estuarine area due to the outflow from the Pearl River hinders the conventional visual census in assessing the megafaunal biodiversity. In this study, the fish and crustacean biodiversity of Hong Kong's western waters, i.e. the outer maritime estuary of the PRD, were studied through the metabarcoding of environmental DNA (eDNA). eDNA from the seawater and sediment samples was extracted from five sites in the region. After testing the performance of two genetic markers, amplicons of the cytochrome oxidase I, amplified by polymerase chain reaction, were subjected to Illumina high-throughput sequencing (MiSeq) analysis. A total of 22 fish species from 17 families and 34 crustacean species from 27 families were identified by blasting the sequences against the NCBI GenBank database, demonstrating segregation between samples from different sites. This study provides insight on the detail distribution of fish assembly in PRD, when compared with a previous eDNA study in the inner brackish PRD.

Portunus pelagicus is exposed to different kinds of microorganisms leading to high metabolic stress that affects its life. The present study evaluates the activity of Phenoloxidase (PO), which is an enzyme that is actively involved in the activation of the immune defense system and hyperglycemia in P. pelagicus challenged with Escherichia coli and Vibrio harveyi injections. The results revealed a major impact of microbial injection on PO activity and significant variations in hemolymph glucose and CHH levels. Reduction of glucose level was observed after 24 h microbial incubation (275.26 ± 28.85 and 175.23 ± 21.70 μg/ml in V. harveyi and E. coli injected crabs, respectively). An elevated level of CHH (13.54 ± 0.55 fmol/ml) was observed in V. harveyi-injected crabs, and increased PO activity was recorded in E. coli-injected crabs. The results of the present study indicate that microbial stress leads to the activation of the defense system and hyperglycemia in P. pelagicus.