The complexity and scale of the sources, types and environmental impacts of persistent solid waste pollution (PSWP) continue to overwhelm the capabilities of government and private efforts to control it. Global cumulative production of virgin plastics is expected to quadruple by 2050 with a concomitant doubling of plastic waste. All nations must take significant steps to realize eventual mitigation of PSWP. These will include adopting a long-term PSWP elimination policy, creating an overarching authority to lead and coordinate a comprehensive national solid waste management program, and creating an International Convention for the Prevention of PSWP to enable global solutions for this global pollution. Initiating these changes will necessitate major, coordinated efforts on the part of environmental organizations, their supporting foundations and concerned citizens.

This research attempted to investigate the plant/soil concentration ratios (CRs) of ¹³⁷Cs and ⁴⁰K in plants that grow on the Anzali Lagoon of the Caspian coast, Iran. The activity concentrations of ¹³⁷Cs and ⁴⁰K were measured in soil samples, annual plants (Echinochloa crus-galli, Digitaria sanguinalis, and Trifolium repens), and perennial plants (Phragmites australis, and Cynodon dactylon). The relationship of activity concentration with soil particle density, and pH of soil samples, CR, and ¹³⁷Cs/⁴⁰K discrimination factor (DF) were determined. The activity concentration of ¹³⁷Cs in the soil, annual plants, and perennial plants ranged between 12- and 124 (Bq/kg dry weight), 2- and 17 (Bq/kg dw), and 2 - and 14 (Bq/kg dw), respectively. The geometric mean (GM) values of DF in annual and perennial plants were 0.57 and 0.55, respectively. The CR for ¹³⁷Cs and ⁴⁰K varied as a non-linear relation in annual plants and perennial plants. This study showed that the CRs for ¹³⁷Cs in annual plants were higher than the CRs for perennial plants.

We reviewed 194 studies concerning POPs in Mediterranean basin; 38% were related to the origin and emission sources, as well as their physico-chemical properties and transport processes and 62% were related to ∑₁₀₋₂₆PAHs and ∑₇₋₄₁PCBs distribution in Mediterranean basin. Only 57% of Mediterranean countries with coasts on the Mediterranean Sea, have a published research papers about POPs. As results of the survey study: Italy, France, Spain and Egypt were identified as the main polluted Mediterranean countries. The highest concentrations were reported at areas influenced by harbor and industrial activities as the case of Gulf of Taranto (Italy), Lazaret Bay (France) and Napels Bay (Italy). However, lack of data is available for some area. We can suggest that Mediterranean Sea is in critical situation and some measures whether on global and regional scale were recommended in order to protect it and save the natural resources for the future generations.

Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) can pose serious threats to the marine benthic ecosystem as it results in a deposition of oil contaminated marine snow on the sediment surface. In a microcosm experiment we investigated the effects of oil in combination with artificial marine snow or kaolin clay on two benthic invertebrate species and benthic meiofauna. The amphipod showed a dose-dependent decrease in survival for both oil-contaminated clay and oil-contaminated marine snow. The gastropod was only affected by the highest concentration of oil-contaminated marine snow and had internal concentrations of PAHs with a similar distribution as oil-contaminated marine snow. Benthic copepods showed higher survival in presence of marine snow. This study revealed that marine snow on the sediment after oil spills affects organisms in a trait-dependent way and that it can be a vector for introducing oil into the food web.

In order to estimate the possible effects of existing ballast tank sediment management routine in ports the respective legal framework from different states was examined and the operational modes of selected Adriatic shipyards was analysed. The goal was to determine if the States' administration and ports' management are aware of risks which sediments pose to human health and environment due to possible presence of harmful aquatic organisms and pathogens (HAOP) or high concentrations of heavy metals. The analysis revealed that sediments from ballast tanks after being collected, are subject to the same handling procedure as any other waste material generated during ships' repair and maintenance. In addition, measures preventing sediment drainage into the sea or procedures for analyzing the presence of heavy metals or toxics have not been identified. The paper proposes the procedures ensuring the more advanced level of protection from HAOP and potentially toxic substances from ballast sediment.

The global plastic economy demands to reduce the flow of plastic into oceans and promote remedial actions for already accumulated seafloor litter. In this perspective, baseline levels of contamination and tools for dating litter items in order to assess the efficacy of those actions, are thus needed. In this note we discuss the utility of introducing the acquisition of shelf-life and labels features from litter items into already established standardized protocols such as the one proposed by MEDiterranean International Trawl Survey (MEDITS). Our investigation was conducted on 612 high resolution images of litter items collected in each haul, which was retrieved during 6 years of surveys (2013–2018) around Sardinian sea (central western Mediterranean). While for the majority of items (89%) expiration date or labels were not present or legible, over 50% of dated items were likely dumped at sea from a period <5 years. In this perspective, this sort of data could represent a useful tool for monitoring the effectiveness of input reduction actions that implicitly rely on the gradual reduction of recently dumped items.

A better understanding of the relationships between heavy metal pollution and sediment sources in different aquatic environments of estuary is needed. The purpose of this paper is to evaluate the levels and spatial distribution of heavy metals (Cu, Zn, Pb, Cd, Hg, and As) of surface sediments collected from 20 stations in the Yangtze River estuary from 2012 to 2016. The results showed that an overall decreasing trend in the concentration of these six types of heavy metals with distance from the shoreline. Typically, there was also a high concentration of heavy metals in muddy areas. Principle component analysis (PCA) and Factor analysis (FA) detected major groups of elements in which three distinct clusters of pollutants and recognized the sources of metals and validate the temporal and spatial variations that are affected by natural and anthropogenic sources linked to their seasonality.

Sediments of Yellow Sea dumping sites (YSDS) collected in 2015 were analyzed using the European Community Bureau of Reference (BCR) sequential extraction method to assess the contamination and potential risk to the environment. Cr, Ni, Cu, and Zn exhibited the most dominant residual fraction, whereas Cd was mostly in the exchangeable fraction and Pb in the reducible fraction. Cr contains a significant amount of oxidizable fraction in the dumping area due to the dumping of tannery sludge with high concentrations of Cr, mainly in the organic matter-bound form. The global contamination factor (GCF) showed that high non-residual fractions of Cd and Pb contributed considerably to contamination. Nevertheless, modified potential ecological risk index (MRI) suggested low ecological risk for metals in YSDS because of the low total content of Cd and the small mobile fraction of other metals.

The study focuses on the impact of life excretion and mucus released by the “biological pollutants” invasive ctenophore Mnemiopsis leidyi and its predator Beroe ovata on the marine environment and lower trophic levels of the Black Sea ecosystem (bacteria, pico-phytoplankton, nano-autotrophic/heterotrophic flagellates, micro-phytoplankton, chlorophyll a, primary production (PP), micro-zooplankton). The chemical and biological variables were analysed in two sets of lab experiments with natural communities from mesotrophic (Gelendzhik) and eutrophic (Varna) coastal waters. While both species altered the chemical properties of experimental media, exerting structural and functional changes in the low food-web biological compartments, the results showed a stronger effect of B. ovata, most likely related to the measured higher rate of excretion and amount of released mucus. In addition the alterations in the Gelendzhik experiment were more pronounced, indicating that environmental implications on lower food-web are more conspicuous in mesotrophic than in eutrophic coastal waters.

With the recovery of whale populations, carcass strandings on beaches are growing. Beach burial is a common management option for stranded carcasses. However, communities fear shark attraction following leachate transport to the ocean via submarine groundwater discharge. Here, a sediment column mesocosm experiment indicated that carcasses can be a localised source of dissolved organic carbon (DOC), phosphate and ammonium to groundwater. The spatial reach of the leachate plume was <2.5 m, while the temporal stabilisation occurred over 100–300 days. No significant chemical signals were observed under a beach-buried carcass, implying effective attenuation of decomposition plumes. For beaches with conditions similar to our one-directional, fast-flowing sediment experiment generating extreme groundwater contamination, it is unlikely that any leachate from a whale carcass would reach the ocean if buried >25 m onshore. Therefore, carcass leachate plumes would only potentially attract sharks to the surf under specific conditions not experienced during our experiments.