Mangroves are complex and dynamic ecosystems highly dependent on diverse microbial activities. In the last decades, these ecosystems have been exposed to and affected by diverse human activities, such as waste disposal and accidental oil spills. Complex microbial communities inhabiting the soil and sediment of mangroves comprise microorganisms that have developed mechanisms to adapt to organic and inorganic contaminants. The resistance of these microbes to contaminants is an attractive property and also the reason why soil and sediment living microorganisms and their enzymes have been considered promising for environmental detoxification. The aim of the present study was to identify active microbial genes in heavy metals, i.e., Cu, Zn, Cd, Pb and Hg, and antibiotic resistomes of polluted and pristine mangrove sediments through the comparative analysis of metatranscriptome data. The concentration of the heavy metals Zn, Cr, Pb, Cu, Ni, Cd, and Hg and abundance of genes and transcripts involved in resistance to toxic compounds (the cobalt-zinc-cadmium resistance protein complex; the cobalt-zinc-cadmium resistance protein CzcA and the cation efflux system protein CusA) have been closely associated with sites impacted with petroleum, sludge and other urban waste. The taxonomic profiling of metatranscriptome sequences suggests that members of Gammaproteobacteria and Deltaproteobacteria classes contribute to the detoxification of the polluted soil. Desulfobacterium autotrophicum was the most abundant microorganism in the oil-impacted site and displayed specific functions related to heavy metal resistance, potentially playing a key role in the successful persistence of the microbial community of this site.

PBDEs and heavy metals are two major contaminants at e-waste disposal sites, but their combined effects remain largely unexplored. In the present study, the transcriptomic profiles of zebrafish larvae were examined after acute exposure of embryos to 200 μg/L BDE-209, 20 μg/L lead (Pb) or their mixture (Mix). Stimulation of steroidogenic pathway and vitellogenesis in the BDE-209 and Mix treatments indicated the estrogenic activities of BDE-209, while Pb antagonized those estrogenic effects in the Mix treatment. Increased heart rates were observed in zebrafish exposed to the Pb and Mix treatments. The cardiac dysfunction probably resulted from the promotion of angiogenesis, increased adrenergic drive and induction of the formation of blood clot. Furthermore, the Pb and Mix treatments activated neuroendocrine regulation of the pituitary in a positive feedback loop, via the thyrotropin-releasing hormone receptor, thus increasing thyroid hormone production self-adaptively. Overall, the interaction between BDE-209 and Pb led to synergistic and antagonistic effects on gene transcriptions, with concerted contribution from their individual toxicological properties.

Biosolids are extensively used in agriculture as fertilizers while offering a practical solution for waste disposal. Many pharmaceutical and personal care products (PPCPs), such as triclosan and triclocarban, are enriched in biosolids. Biosolid amendment changes soil physicochemical properties, which may in turn alter the persistence of PPCPs and hence the risk for secondary contamination such as plant uptake. To delineate the effect of biosolids on PPCPs persistence, triclosan and triclocarban were used as model compounds in this study and their sorption (Kd) and persistence (t1/2) were determined in different soils before and after biosolid amendment. Biosolids consistently increased sorption of triclosan and triclocarban in soil. The Kd of triclosan increased by 3.9–21 times following amendment of a sandy loam soil with biosolids at 2–10%. The persistence of both compounds was prolonged, with t1/2 of triclosan increasing from 10 d in the unamended soil to 63 d after biosolid amendment at 10%. The relationship between t1/2 and Kd was further examined through a meta-analysis using data from this study and all relevant published studies. A significant linear relationship between t1/2 and Kd was observed for triclosan (r2 = 0.69, p < 0.01) and triclocarban (r2 = 0.38, p < 0.05) in biosolid-amended soils. On the average, when biosolid amendment increased by 1%, t1/2 of triclosan was prolonged by 7.5 d, while t1/2 of triclocarban was extended by 4.7 d. Therefore, biosolid amendment greatly enhances persistence of triclosan and triclocarban, likely due to enhanced sorption or decreased chemical bioavailability. This finding highlights the importance to consider the effect of biosolids when evaluating the environmental risks of these and other biosolid-borne PPCPs.

Coastal regions are characterized by intense human activity and climatic pressures, often intensified by competing interests in the use of marine waters. To assess the effect of public spending on the regional economy, an econometric model is here proposed. Not only are the regional investment and the climatic risks included in the model, but also variables related to the anthropogenic pressure, such as population, economic activities and waste production. Feedback effects of economic and demographic expansion on the pollution of coastal areas are also considered. It is found that dangerous waste increases with growing shipping and transportation activities and with growing population density in non-touristic coastal areas. On the other hand, the amount of non-dangerous wastes increases with marine mining, defense and offshore energy production activities. However, lower waste production occurs in areas where aquaculture and touristic industry are more exploited, and accompanied by increasing regional investment in waste disposal.

The Yellow River Delta (YRD) is a large region of China with complex pollution sources and a long history of environmental deterioration. Despite this, relatively little data exists on the status of important contaminants of concern in this region. Here, we review the literature on the status of key persistent organic pollutants (POPs) of concern including organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) in the YRD. Sources, source identification methods, and spatial distribution patterns are presented. Additionally, POPs contamination levels reported in the literature were evaluated against popular regulatory limits worldwide to form a basis for overall environmental health. Our review determined that OCPs in the YRD originated mainly from current pesticide use and past agricultural pesticide application. Sources of PAHs included petrochemical inputs, coal fired plants, and wood combustion. PCB levels were impacted by the petrochemical industry as well as waste disposal of PCB containing equipment. OCPs exhibited a spatial distribution pattern that increased along the urban–rural gradient, while the opposite was seen for PAHs and PCBs. Comparisons of POPs contamination levels in the YRD with popular regulatory limits suggest that the extent of PCB contamination all mediums (sediment, soil, water, and biota) exceeded that of PAHs and OCPs. Overall pollution levels in the YRD seem to be in control; however, levels from heavily polluted point sources raise numerous concerns about the ecological health of the region and require more attention from regulatory authorities.

High spatial variability in polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, such as DDTs, and polybrominated diphenylethers was observed in plastic pellets collected randomly from 41 beaches (15 cities) in 2010 from the coast of state of São Paulo, southeastern Brazil. The highest concentrations ranged, in ng g−1, from 192 to 13,708, 3.41 to 7554 and <0.11 to 840 for PAHs, PCBs and DDTs, respectively. Similar distribution pattern was presented, with lower concentrations on the relatively less urbanized and industrialized southern coast, and the highest values in the central portion of the coastline, which is affected by both waste disposal and large port and industrial complex. Additional samples were collected in this central area and PCB concentrations, in ngg−1, were much higher in 2012 (1569 to 10,504) than in 2009/2010 (173 to 309) and 2014 (411), which is likely related to leakages of the PCB commercial mixture.

In the present paper we suggest a novel calibration method of the model for hydrodynamic and contaminant transport using the example of a sewage disposal site set up uninsulated in a sandy environment. With the hydrodynamic model we applied time-dependent model calculations in order to fit the individual hydrodynamic parameters. For the calibration of the transport model, sodium was chosen, which has a negligible retardation factor. We demonstrated that this approach is suitable for creating a model that provides calculated results comparable to the actually measured, experimental ones. The created model proved to be appropriate for use in the estimation of the maximal spatial extension of the contamination, which—in the case of the investigated sewage disposal site—was found to be 0.1 km² in the near-surface (1–3 m deep) layers, whereas it was three times higher at a depth of 40–60 m.

Improved understanding of the relationships between heavy metals fractionation in agricultural soils and biological uptake could be obtained by analysing samples of biota in parallel with sequential extraction of their grown media. The overall goals of this study were to identify the characteristics of metal fractions and their bioavailability to maize and potato plants in the agricultural land of the Ibar River in southern Serbia and northern Kosovo. The concentrations of Pb, Zn, Cd, Ni, Cr and Cu in soil and vegetable samples were determined by the ICP-OES method. Pb/Zn production and industrial waste disposal significantly increased the pseudo-total concentrations of heavy metals in the soil together with their mobile and potentially bioavailable amounts. The Pb concentrations in the vegetable samples were generally above the EU maximum permitted concentrations in foodstuffs. However, the concentrations of Zn, Ni, Cr and Cu in the vegetables were below the critical levels. The results of the present study indicated that the intensive industrial production of Pb/Zn over the years and permanent pollution were responsible for the environmental contamination by heavy metals in the study area, particularly by Pb and Zn. The quantity of the mobile and potentially bioavailable heavy metals in the studied soils threatens the quality of Zea mays L. and Solanum tuberosum L. crops, with a real risk that these elements could enter the food chain.

This study proposes a factorial inexact stochastic fuzzy chance constraint programming framework for dealing with uncertainties in municipal solid waste management under consideration of greenhouse gas (GHG) emission trading. It can reflect uncertainties expressed as fuzzy, interval, and random variables and generate desired management strategies for minimizing the integrated cost for solid waste disposal and purchasing GHG emission credit. Moreover, multilevel factorial analysis is conducted to reveal the main and interactive effects of uncertain parameters. The results show that effective waste allocation schemes can be obtained to meet the waste disposal demands and GHG emission requirements under different α-cut levels. The changes in the fuzzy confidence level have impacts on the waste allocation schemes, especially for the waste flow to the incinerator. The disposal cost differs across the three levels of 0.3, 0.5, and 0.7 for incinerator capacity constraint when the fuzzy confidence level of composting capacity constraint is equal to 0.5, implying the existence of the interaction between uncertainties in the incinerator and composting facility. Comparison between the waste management practices with and without considering GHG emission requirements indicates that the purchase of GHG emission credits would contribute about 10 % to the total cost, which would not be influenced significantly by the α-cut level.

Concerns over the environmental and waste disposal problems created by the large amounts of by-products generated from fish processing industries are increasing worldwide. The bioconversion of those marine waste by-products through the enzymatic hydrolysis of their protein content offers the possibility for the development of bioactive peptides for use in various biotechnological applications. The present study aimed to investigate and evaluate the biological and functional properties of smooth hound (Mustelus mustelus) protein hydrolysates (SHPHs) obtained by treatment with intestinal and gastric enzyme preparations from M. mustelus viscera and porcine pancreatin. The results revealed that the SHPHs exhibited different degrees of hydrolysis and antioxidant activity. The hydrolysate produced by the intestinal crude extract presented the highest rate of antioxidative activity, showing an IC₅₀ value of 1.47 ± 0.07 mg/mL in 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assays. The alkaline protease extract from the intestine of M. mustelus produced hydrolysate with the highest angiotensin I-converting enzyme (ACE) inhibitory activity (82 ± 1.52 % at 2 mg/mL). All the protein hydrolysates showed excellent solubility and interfacial properties that were governed by pH. The major amino acids detected in SHPHs were glutamic acid/glutamine, aspartic acid/asparagine, histidine and arginine, followed by methionine, phenylalanine, serine, valine and leucine. Overall, the results indicated that smooth hound by-products can be used to generate high value-added products, thus offering a valuable source of bioactive peptides for application in wide range of biotechnological and functional food applications.