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.

St Georges Bay of Lebanon's coast is an open bay to the Mediterranean Sea. It is exposed to numerous anthropogenic activities such as industrial effluent, untreated wastewater discharge and maritime activities resulting in increasing chemical contamination, especially with trace metals. Contamination with trace metals (Cu, Cd, Co, Pb, As, Ag and Hg) and the influence of early diagenesis on their distribution were studied on both sediments and waters. For this purpose, sediment cores were collected, then treated under inert atmosphere to retrieve pore waters and solid fraction. The area appears to be seriously impacted by the materials transported by the Beirut River and/or by direct inputs, and recent land reclamation using dumpsite material. The sediments showed a significant level of contamination. Element mobility was studied by selective extraction on sediments. The mobility of trace elements from solid fraction to pore waters is controlled by the Fe/Mn cycle and organic matter.

Comprehensive synthesis of the harmful invader ctenophore Mnemiopsis leidyi adaptive strategies and its validation as of a single polymorphic species has been presented. Its high morphological and physiological variability in different environments were demonstrated. M. leidyi being native for eastern coasts of Americas, since the early 1980s began to invade in the Eurasian seas and now it is recorded in a wide range of recipient habitats. Analysis of M. leidyi morphological and eco-physiological variability, phenology and rate of reproduction was performed for different environments based on author's data and published sources. Prominent morphological features of M. leidyi, previously used to subdivide it in three species, in fact are a phenotypical variability, associated with environmental conditions. In recipient environments, M. leidyi pre-adapts for rapid colonization, due to a high metabolism and reproduction rates. It created extensive populations with the various patterns of annual cycle and distribution and heavily impacted the ecosystems.

This study is focused on the analysis of microplastic concentrations in the surface waters of the White, Barents and Kara Seas. Sampling took place during the “Arctic Floating University 2018” expedition using a manta trawl. Particularly high concentrations of the microplastics were found off the west coast of Novaya Zemlya archipelago with a maximum in a highly productive region – Gusinaya bank. The microplastic distribution pattern in the Barents Sea correlates both with the oceanic circulation and the fishing activities. The results show the first recorded estimation of microplastic concentrations in the White Sea with the higher concentrations located in the area affected by the Severnaya Dvina River discharge. Relatively low concentrations of microplastics were found in the Kara Sea.

A model of the beach process of marine plastics was proposed based on the assumption of the beaching and backwashing flux balance, and its applicability was examined by means of time-invariant linear system analysis and particle tracking experiments with respect to the ratio between the residence time of plastics on a beach (τᵣ) and the period of nearshore current variability (T₀). Based on the theory, the balance was expected to hold when τᵣ/T₀ was much smaller than 1; however, good agreement was obtained between the theory and the particle tracking method for much larger values of τᵣ/T₀. The parameters, which are diagnostically given in the model, will be prognostically decided by the coastal dynamics in the future to develop robust beach process models. Nevertheless, we believe that a diagnostic approach would be another pillar in the strategy for estimating the amounts and distributions of marine plastics in the coming years.

The present study aims to examine the distribution, sources and potential risks of toxic metals in the northern Bay of Bengal, Bangladesh. We found Cu, Pb, Zn and Hg exhibited similar spatial distribution pattern. Influenced by the Ganges-Brahmaputra River and the Karnafuli River, there were higher concentrations of these metals associated with the finer sediment and higher TOC in the northeastern portion of the study area. Moreover, coal transportation was assumed to account for the distinctive spatial distribution of As with higher concentration down the Port of Chittagong in the eastern boundary. Chemical-screening level assessment demonstrated the majority of the metals exceeded the threshold effect values, indicating certain possibility of adverse effect. The concentrations of Ni were higher than the possible hazardous values, suggesting high possibility of harmful consequences. The uncontaminated sediments mainly distributed in northwestern and the central portions affected by the delta erosion and marine transported sediments.