PURPOSE OF REVIEW: The use of algae for remediation of toxic pollutants seems to be promising since they also provide some advantages such as the production of valuable products and their capability to capture CO₂ during the photosynthesis, which potentially decrease greenhouse gas emission. This paper reviews the evidence for highlighting the effectiveness of the use of living or non-living algal cells for treating polluted waters. RECENT FINDINGS: Removal efficiency and sorption capacity of algal non-living cells are higher than in living cells because of cell membrane disruption (leading to enhancement of intracellular pollutants binding) and the improvement of specific surface area. For the kinetic and isotherm modeling, there is no single powerful model for a wide range of pollutants and type of algae, indicating that the mechanism is quite specific depending on the type of algae, type of pollutants, and environmental conditions. The removal mechanism of pollutants by living and non-living algae can be considered as an exothermic reaction and physical sorption from many published reports. The use of non-living cells was more effective compared to living cells for a wide range of pollutants since the non-living cells performed better removal efficiency and sorption capacity as well as easy to handle. This review is useful to pave a good strategy for designing a greener technology for future environmental pollutants remediation particularly within the domain of algal-based technology.

In the last decade, the salmon aquaculture industry has considerably increased the use of lumpfish juveniles as cleaner fish. Potential escape of reared lumpfish into the wild may spread diseases or genetically contaminate wild stocks. The guidelines for minimum sizes of cleaner fish to use in aquaculture cages are currently based on simple mesh penetration tests. However, these guidelines do not consider the potential compressibility of fish or changes in mesh state due to factors such as sea conditions and maintenance operations. This study shows that the industry-recommended minimum stocking sizes for a given mesh size may result in escape risk and that ignoring fish compressibility and mesh state can lead to underestimation of the lumpfish sizes that are able to escape. Our results can be used to develop new guidelines that will contribute to reduced escape of lumpfish from salmonid farms and lessen the potential environmental consequences.

Surface sediments from the Yeşilırmak River and the near coastal area in the Black Sea were collected using sediment traps to assess the spatial distributions of persistent organic pollutants and find their potential sources. Analyses were carried out to determine the concentrations of the persistent organic pollutants of seventeen polychlorinated dibenzo-p-dioxins and dibenzofurans, sixteen polycyclic aromatic hydrocarbons, seven polychlorinated biphenyls, and eight organochlorine pesticides using high-resolution gas chromatography–mass spectrometry and gas chromatography-tandem mass spectrometry systems. Analysis showed that the three main components of persistent organic pollutants (polychlorinated dibenzo-p-dioxins and dibenzofurans, polycyclic aromatic hydrocarbons, and organochlorine pesticides) primary sources are industrial activities. In addition, the widespread occurrence of persistent organic pollutants in the watershed surface sediments taken from the Yeşilırmak River basin showed that agricultural and urban areas are also diffuse persistent organic pollutants sources.

Marine litter is recognized as an increasing component of marine ecosystem pollution. In this baseline study, we document the magnitude, types, sources, and potential impacts of litter on six coral reefs in East Sabah. We applied a simplified classification of litter to extract abundance data from video transects. The average density was 10.7 items per 100 m². Plastics represent 91% and the remaining 9% were metal, glass, and wood. Most (~70%) plastics are single-use items derived from dumping. Discarded fishing gear accounts for ~25%. Litter pollution increases closer to urban developments, with Sakar reef having higher densities (51 items per 100 m²), and higher Clean Coast Index (CCI = 10.2, dirty) and higher Plastic Abundance Index (PAI = 4.68) scores. This method could and should be readily integrated into ongoing monitoring programs to support assessments of the extent and magnitude of marine litter pollution on reefs worldwide.

A mesocosm experiment was conducted on the Qingdao coast to study the effects of nutrient enrichment on the physiological responses of Ulva prolifera and the changes in the entire culture system during decomposition of algal blooms. The decomposition trend of U. prolifera off the Qingdao coast was slightly retarded by nutrient enrichment, and could not be reversed to positive growth. The decomposition of U. prolifera was divided into two stages: the early-stage (0–9 d) and the late-stage (9–19 d). High nutrient levels enhanced the amounts of carbon and nitrogen fixed by U. prolifera and accelerated the subsequent degradation of organic matter. The concentration and composition of amino acids in solution also changed, reducing the bioavailability of dissolved organic matter in seawater. This study evaluated the actual decomposition process of green tides, which will help to assess the impact of green tides on coastal ecosystems and the circulation of biogenic elements.

PURPOSE OF REVIEW: Untreated wastewater discharge can significantly and negatively impact the state of the environment. Rapid industrialization and economic development have directly contributed to land and water pollution resulting from the application of many chemicals such as organic dyes, pharmaceuticals, and industrial reagents. The removal of these chemicals before effluent discharge is crucial for environmental protection. This review aims to explore the importance of functionalized materials in the preparation of biocatalytic systems and consider their application in eliminating water pollutants. RECENT FINDINGS: Wastewater treatment methods can be classified into three groups: (i) chemical (e.g., chemical oxidation and ozonation), (ii) physical (e.g., membrane separation and ion exchange), and (iii) biological processes. Biological treatment is the most widely used method due to its cost-effectiveness and eco-friendliness. In particular, the use of immobilized enzymes has recently become more attractive as a result of scientific progress in advanced material synthesis. The selection of an appropriate support plays an important role in the preparation of such biologically active systems. Recent studies have demonstrated the use of various materials for enzyme immobilization in the purification of water. This review identifies and discusses different biocatalytic systems used in the enzymatic degradation of various water pollutants. Materials functionalized by specific groups can serve as good support matrices for enzyme immobilization, providing chemical and thermal stability to support catalytic reactions. Enzymatic biocatalysis converts the pollutants into simpler products, which are usually less toxic than their parents. Due to immobilization, the enzyme can be used over multiple cycles to reduce the cost of wastewater treatment. Future studies in this field should focus on developing new platforms for enzyme immobilization in order to improve degradation efficiency.

Resource acquisition and allocation impacts individual fitness. Using pellet analysis of breeding adults and stable isotopes of carbon and nitrogen of down feathers of Kelp Gull (Larus dominicanus) nestlings, we evaluated the relationship between urban refuse (beef and chicken) and natural food (fish) consumption of individual females during the pre-incubation period, with fecundity and young nesting's success in the Río de la Plata Estuary in Uruguay. Assimilated urban refuse positively correlated with egg weight and negatively with young nestling's success. This suggests a possible impact of urban refuse foraged by females during the pre-incubation period on their immediate fecundity (positively) and young nestling's survival (negatively). Differences between studies at the individual and colony levels are also discussed in light of an “ecological fallacy” of interpretation and we thus argue for the need of additional research to evaluate this relationship further, considering potential confounding factors.

Mangrove has been destroyed and reforestation is often undertaken, but whether a regenerated forest could restore its ecological function is not clear. This study compares microbial community structure and function in sediment of the 17-years old natural regenerated mangrove forest (Y17) with the original forest (Y74). No significant differences in phospholipid fatty acid (PLFA) profiles and microbial metabolism of most carbon substrates were found between these two forests. However, activities of dehydrogenase, protease, cellulase and phosphatase were lower in Y17 than Y74, and some specific microbial functions were also different. Both forests exhibited significant seasonal differences in enzyme activities and microbial characteristics, but such difference was larger in Y17 than Y74, indicating the regenerated forest was more sensitive to season. Correspondence analysis based on PLFA profiles and enzyme activities revealed the microbial community in Y17 was comparable to Y74, suggesting sediment microbial characteristics in natural regenerated mangroves could be restored.

The Rapid Oil Spill Hazard Assessment is presented as a demonstration of concept for a tool providing a framework for managers and planners to assess potential impact areas of oil spills. The tool consists of precomputed oil spill scenarios derived from the analysis of twenty years of modeled current data using Self-Organizing Maps to identify 16 representative patterns. These patterns were used to provide boundary conditions for hydrodynamic and wave models to generate higher resolution current fields, used to drive a Lagrangian oil particle transport model creating the most probable oil spill dispersion patterns. To demonstrate the concept, the tool is applied to the Perdido region in the western Gulf of Mexico. A total of 896 oil spill simulations were performed, considering surface and bottom spills, and were stored in a database for easy access to map arrival probabilities and times to be used in risk and vulnerability analysis.

PURPOSE OF REVIEW: Major waterborne viruses comprise numerous variants rather than only a master sequence and form a genetically diverse population. High genetic diversity is advantageous for adaptation to environmental changes because the highly diverse population likely includes variants resistant to an adverse effect. Disinfection is a broadly employed tool to inactivate pathogens, but due to virus evolvability, waterborne viruses may not be inactivated sufficiently in currently applied disinfection conditions. Here, by focusing on virus population genetics, we explore possibility and factor of emergence of disinfection sensitivity change. RECENT FINDINGS: To test whether virus population obtains disinfection resistance, the evolutionary experiment developed in the field of population genetics has been applied, indicating the change in disinfection sensitivity. It has been also confirmed that the sensitivity of environmental strains is lower than that of laboratory strains. In some of these studies, genetic diversity within a population less sensitive to disinfection is higher. Researches in virus population genetics have shown the contribution of intra-population genetic diversity to virus population phenotype, so disinfection sensitivity change may attribute to the genetic diversity. The research elucidating a relationship between virus evolution and disinfection has only recently begun, but significant information about the relationship has been accumulated. To develop an effective disinfection strategy for the control of waterborne virus spread, we need to clarify whether disinfection practice truly affects virus outbreaks by refining both laboratory and field experiments related to virus evolution in the disinfection-exerted environment.