There is an increasing awareness of microplastics within the global problem of marine plastic pollution. In 2018, small plastic pellets or “nurdles” were observed on the beaches of Corpus Christi, Texas. A citizen science project, “Nurdle Patrol,” was established by the Mission-Aransas National Estuarine Research Reserve to monitor the presence of nurdles, with volunteer interest enabling this project to expand across the Gulf of Mexico region. This case study describes the sampling methodology, the policy framework, and initial quantitative data from the citizen science project on nurdle distribution along the Gulf coast. A total of 2042 Nurdle Patrol surveys have been conducted by 744 citizen scientists covering shorelines from Mahahual, Mexico to Fort Jefferson, Florida. All 20 of the highest standardized nurdle counts were recorded at sites in Texas. Results can inform decision-maker response across regulatory scales and further research on nurdle pollution.

The emergence of a red tide resulting in yellow-brownish discoloration of waters in Porto Cesareo bay (Italy) during July–August 2018 is reported. The species responsible for the bloom was the dinoflagellate Margalefidinium cf. polykrikoides. Cell densities reached 9.1 × 10⁶ cells L⁻¹ during the initial outbreak. A second peak was observed about three weeks later reaching 6.7 × 10⁵ cells L⁻¹. Study of live specimens showed great variation in cell size and shape. Different cyst morphotypes were found in the water samples and in the sediment. For the first time, we followed several stages of the life cycle of M. cf. polykrikoides in natural samples. Fish die-offs in the bay were not observed, however this high-density bloom may have caused consequences on the ecosystem (amount of mucilage on the beach) and in turn, on tourism that is the main activity in the area during the summer season.

It has been predicted that Grateloupia turuturu, native of the cold-temperate waters of Japan, is one of the most invasive marine species considered as a threat to global marine biodiversity. However, few studies have been carried out to assess the extent of its spread worldwide. Its seasonal dynamics in the Mar Piccolo of Taranto, a transitional water system in the Northern Ionian Sea, were observed for ten years. Systematic monthly observations were carried out from 2008 to 2018. The length of thalli and density were measured alongside the seawater temperature. Data were processed by means of non-parametric statistical analyses. No invasive behavior was detected for G. turuturu. It seems well established in the Mar Piccolo even though its population is limited to the station of first detection. However, due to its shown preference for plastic substrate, it could become a vector of another urgent threat, that is plastic pollution.

Core sediment samples were collected from five mangrove ecosystems along northern Kerala coast (Kunjimangalam: S1, Pazhayangadi: S2, Pappinissery: S3, Thalassery: S4, and Kadalundi: S5) to assess the status of heavy metal pollution. S1 recorded comparatively lower metal concentration at surface (except Pb) due to low organic content and sandy texture, while the reverse was true for S3. Higher metal contents were recorded at S5 (0–5 cm), which was attributed to its unique biogeochemical behavior. Enrichment factor and geoaccumulation index indicated moderate enrichment for Cd, and the pollution load index revealed progressive deterioration of sediment quality at S5 (0–5 cm). There was no harmful effect of trace metals on biological community (except Ni) according to Sediment Quality Guidelines. Major processes controlling trace metal accumulation in these systems are diagenetic processes, precipitation of heavy metals as sulfides, and the presence of Fe, Mn-oxy hydroxides, which act as adsorption sites for other metals.

The existence of microplastics (MPs) in canned fish (tuna and mackerel) samples was investigated and their composition, possible sources and potential intake were assessed. Light and fluorescence microscopy were used for the quantification of potential MPs. Furthermore, micro-Raman microscopy, and scanning electron microscopy coupled with an energy dispersive X-ray were used to identify the polymer types and composition of MPs. The results showed that 80% of samples had at least one plastic particle and fibers were the most abundant shapes of MPs. Moreover, polyethylene terephthalate (32.8%) was the most common polymer type in canned fish samples. The fish, food additives, and contact materials during the cleaning and canning process are possible sources of MPs. Human intake estimation of MPs showed the possibility of plastics absorption by humans who consume canned fish several times/week. Hence, the results of this study showed the importance of MPs' guidelines for food safety and hygiene.

We examine the use of surrogates in the measurement of concentrations of polycyclic aromatic hydrocarbons (PAH) in marine sediment, consider shortcomings of current interpretations of the results from this widely used approach, and propose an alternative data treatment. We focus on the current common practice of accepting all data within a predefined range of acceptable recoveries as equally valid and propose treating surrogate recovery data as one component of measurement uncertainty. Our analysis leads us to conclude that the more uniform surrogate recoveries are, the more justified the assumption that they reveal measurement bias and appropriately can be used as corrections; but that the less uniform recoveries are, the greater the need to treat them as a source of measurement uncertainty. We recognize that acceptance of the ideas presented here will require much thought and refinement by the environmental analytical community. We welcome a thorough discussion.

Coastal areas with important economic activities have high levels of contamination by metals, pathogenic bacteria, among other contaminants. The emergence of antibiotic-resistant bacteria is a global problem of public health. Carbapenem resistant Enterobacteriaceae (CRE) are a serious threat. The occurrence of carbapenem resistant bacteria was investigated in waters and sediments of a Brazilian coastal area, characterized by high levels of contamination. The samples of water and sediment were collected in two areas of the coast of São Paulo (Brazil). The study involved the characterization of the molecular mechanisms associated with the carbapenem resistance phenotype. No genes were detected for β-lactamases but the absence and/or presence of mutations in outer membrane proteins (OMPs) may justify the detected phenotype. The presented results show the need for further studies that allow a review of the current legislation and the importance of the reevaluation of monitoring policies of these environments.

Jellyfish are voracious planktonic predators that may be susceptible to ingesting microplastics. We measured rates of ingestion and egestion of microbeads by Aurelia aurita (Scyphozoa) and evaluated whether ingesting microbeads affected metabolism or gut epithelia. Ingestion rates were measured by exposing medusae to microbeads and randomly sampling them 6 times over a 32 h period to determine the number of microbeads in their tissues. Egestion rates were measured by exposing medusae to microbeads for 1 h before transferring them to kreisels without microbeads and sampling them 6 times over 8 h. Respiration rates of medusae were determined using incubations and potential damage to gut epithelia was evaluated using histopathology. Medusae ingested few microbeads and egested them within 8 h. Microbeads had no effect on respiration and the histology. We concluded that the medusae may recognise microbeads as non-food particles and that their ingestion caused undetectable physiological and histological harm.

This review aims to briefly describe the potential role of dehalogenase-producing halophilic bacteria in decontamination of organohalide pollutants. Hypersaline habitats pose challenges to life because of low water activity (water content) and is considered as the largest and ultimate sink for pollutants due to naturally and anthropogenic activities in which a substantial amount of ecological contaminants are organohalides. Several such environments appear to host and support substantial diversity of extremely halophilic and halotolerant bacteria as well as halophilic archaea. Biodegradation of several toxic inorganic and organic compounds in both aerobic and anaerobic conditions are carried out by halophilic microbes. Therefore, remediation of polluted marine/hypersaline environments are the main scorching issues in the field of biotechnology. Although many microbial species are reported as effective pollutants degrader, but little has been isolated from marine/hypersaline environments. Therefore, more novel microbial species with dehalogenase-producing ability are still desired.