Ammonia emission is one of the dominant pathways of nitrogen fertilizer loss from rice fields in China. It is difficult to measure ammonia emissions by high-frequency sampling with the chamber methods widely used in China, which is of great significance for investigating the environmental effects on the ammonia emissions. The chamber methods also can not accurately determine the ammonia emissions. In this study, the backward Lagrangian stochastic dispersion model, with ammonia concentrations continuously measured by the open-path tunable diode laser absorption spectroscopy technique, was used to determine ammonia emissions from a rice field after fertilizer application at excessive (270 kg N ha⁻¹) and appropriate (210 kg N ha⁻¹) rates in the Taihu Lake Region of China. High temporal resolution measurements of ammonia emissions revealed that high intraday fluctuations of ammonia emissions were significantly affected by the meteorological conditions. Multiple regression analysis showed a dominant solar radiation dependence of intraday ammonia emission cycles, especially during the rice panicle formation stage. The NH₄⁺-N concentrations of the surface water of the rice field were found to be the decisive factor that influenced interday dynamics of ammonia emissions. Accurate quantifications of ammonia emissions indicated that the total ammonia losses under appropriate nitrogen application rate were 27.4 kg N ha⁻¹ during the rice tillering stage and 11.2 kg N ha⁻¹ during the panicle formation stage, which were 29.4% and 17.0% less than those under traditional excessive nitrogen application rate used by the local farmers, respectively. The ammonia loss proportions during the rice panicle formation stage were significantly lower than those of the tillering stage, which might be due to different nitrogen application rates and environmental effects during the two stages. This study indicated that the open-path tunable diode laser absorption spectroscopy technique could facilitate the investigation of high temporal resolution dynamic of ammonia emissions from farmland and the environmental influence on the ammonia emissions.

Cadmium (Cd) is a toxic metal that contributes to human diseases such as pediatric cancer and cardiovascular dysfunction. Epigenetic modification caused by Cd exposure is the major factor in etiology of environmentally-relevant diseases. However, the underlying epigenetic mechanism for Cd uptake and accumulation in food crops, particularly those growing in Cd-contaminated environments, is largely unknown. This study investigated uncharacterized regulatory mechanisms and biological functions of global DNA hypomethylation at CG sites that are associated with gene expression for Cd detoxification and accumulation in the food crop rice. Mutation of the CG maintenance enzyme OsMET1 confers rice tolerance to Cd exposure. Genome-wide analysis of OsMET1 loss of function mutant Osmet1 and its wild type shows numerous loci differentially methylated and upregulated genes for Cd detoxification, transport and accumulation. We functionally identified a new locus for a putative cadmium tolerance factor (here termed as OsCTF) and demonstrated that Cd-induced DNA demethylation is the drive of OsCTF expression. The 3′-UTR of OsCTF is the primary site of DNA and histone (H3K9me2) demethylation, which is associated with higher levels of OsCTF transcripts detected in the Osmet1 and Ossdg714 mutant lines. Mutation of OsCTF in rice led to hypersensitivity to Cd and the Osctf line accumulated more Cd, whereas transfer of OsCTF back to the Osctf mutant completely restored the normal phenotype. Our work unveiled an important epigenetic mechanism and will help develop breeding crops that contribute to food security and better human health.

Pesticides pollution has caused serious environmental problems in recent years, and mounting evidence has shown that more and more insecticides have serious risk in human health. Emamectin Benzoate formally regarded as a highly safety insecticide based on its exclusive targets, but the cytotoxicity to human lung was ignored for a long time. In the present study, bioassay experiments were used to assess the toxicity of the Emamectin Benzoatein on human non-target cells including cell viability assay, DNA damage assay, flow cytometer assay and western blotting assay. The results indicated that Emamectin Benzoatecan cause the inhibition of the proliferation, cytochrome c release, activation of caspase-3/9 and increase Bax/Bcl-2 ratio, which means it induced the cytotoxicity on 16HBE cells associated with the mitochondrial apoptosis. Besides, the DNA damge caused by the Emamectin Benzoate suggest it has a potential genotoxic effect on human lung cells.

Glyphosate, introduced by Monsanto Company under the commercial name Roundup in 1974, became the extensively used herbicide worldwide in the last few decades. Glyphosate has excellent properties of fast sorption in soil, biodegradation and less toxicity to nontarget organisms. However, glyphosate has been reported to increase the risk of cancer, endocrine-disruption, celiac disease, autism, effect on erythrocytes, leaky-gut syndrome, etc. The reclassification of glyphosate in 2015 as ‘probably carcinogenic’ under Group 2A by the International Agency for Research on Cancer has been broadly circulated by anti-chemical and environmental advocacy groups claiming for restricted use or ban of glyphosate. In contrast, some comprehensive epidemiological studies involving farmers with long-time exposure to glyphosate in USA and elsewhere coupled with available toxicological data showed no correlation with any kind of carcinogenic or genotoxic threat to humans. Moreover, several investigations confirmed that the surfactant, polyethoxylated tallow amine (POEA), contained in the formulations of glyphosate like Roundup, is responsible for the established adverse impacts on human and ecological health. Subsequent to the evolution of genetically modified glyphosate-resistant crops and the extensive use of glyphosate over the last 45 years, about 38 weed species developed resistance to this herbicide. Consequently, its use in the recent years has been either restricted or banned in 20 countries. This critical review on glyphosate provides an overview of its behaviour, fate, detrimental impacts on ecological and human health, and the development of resistance in weeds and pathogens. Thus, the ultimate objective is to help the authorities and agencies concerned in resolving the existing controversies and in providing the necessary regulations for safer use of the herbicide. In our opinion, glyphosate can be judiciously used in agriculture with the inclusion of safer surfactants in commercial formulations sine POEA, which is toxic by itself is likely to increase the toxicity of glyphosate.

Previous in vitro studies have indicated that 2,3,3′,4,4′,5-hexachlorobiphenyl (PCB 156) may be a new contributor to metabolic disruption and may further cause the occurrence of nonalcoholic fatty liver disease (NAFLD). However, no study has clarified the specific contributions of PCB 156 to NAFLD progression by constructing an in vivo model. Herein, we evaluated the effects of PCB 156 treatment (55 mg/kg, i.p.) on the livers of C57BL/6 mice fed a control diet (CD) or a high-fat diet (HFD). The results showed that PCB 156 administration increased intra-abdominal fat mass, hepatic lipid levels and dyslipidemia in the CD-fed group and aggravated NAFLD in HFD-fed group. By using transcriptomics studies and biological methods, we found that the genes expression involved in lipid metabolism pathways, such as lipogenesis, lipid accumulation and lipid β-oxidation, was greatly altered in liver tissues exposed to PCB 156. In addition, the cytochrome P450 pathway, peroxisome proliferator-activated receptors (PPARs) and the glutathione metabolism pathway were significantly activated following exposure to PCB 156. Furthermore, PCB 156 exposure increased serum transaminase levels and lipid peroxidation, and the redox-related genes were significantly dysregulated in liver tissue. In conclusion, our data suggested that PCB 156 could promote NAFLD development by altering the expression of genes related to lipid metabolism and inducing oxidative stress.

Disinfection means the killing of pathogenic organisms (e.g. bacteria and its spores, viruses, protozoa and their cysts, worms, and larvae) present in water to make it potable for other domestic works. The substances used in the disinfection of water are known as disinfectants. At municipal level, chlorine (Cl₂), chloramines (NH₂Cl, NHCl₂), chlorine dioxide (ClO₂), ozone (O₃) and ultraviolet (UV) radiations, are the most commonly used disinfectants. Chlorination, because of its removal efficiency and cost effectiveness, has been widely used as method of disinfection of water. But, disinfection process may add several kinds of disinfection by-products (DBPs) (∼600–700 in numbers) in the treated water such as Trihalomethanes (THM), Haloacetic acids (HAA) etc. which are detrimental to the human beings in terms of cytotoxicity, mutagenicity, teratogenicity and carcinogenicity. In water, THMs and HAAs were observed in the range from 0.138 to 458 μg/L and 0.16–136 μg/L, respectively. Thus, several regulations have been specified by world authorities like WHO, USEPA and Bureau of Indian Standard to protect human health. Some techniques have also been developed to remove the DBPs as well as their precursors from the water. The popular techniques of DBPs removals are adsorption, advance oxidation process, coagulation, membrane based filtration, combined approaches etc. The efficiency of adsorption technique was found up to 90% for DBP removal from the water.

Under anaerobic conditions, ammonium (NH₄⁺) can react with nitrite (NO₂⁻) and sulfate (SO₄²⁻), termed nitrite-anammox (NirAnammox) and sulfate-anammox (Sulfammox), respectively. However, how to remove NH₄⁺ and SO₄²⁻ together from leachate is unclear. In this study, NirAnammox and Sulfammox cooperatively achieved nitrogen and sulfate removal from leachate using a biological process at low temperature (14–15 °C). NH₄⁺, total nitrogen (TN), and SO₄²⁻ concentrations in the influent were 610–700, 670–900, 1870–1920 mg/L, respectively, and 10 ± 1, 35 ± 3, and 897.7 ± 10 mg/L, respectively, in the effluent. Sulfammox, and NirAnammox (including partial nitrification) removed 44.2% and 35.46% of the NH₄⁺, respectively. Therefore, because leachate contains high concentrations of NH₄⁺ and SO₄²⁻, NirAnammox and Sulfammox can easily occur together, with nitrogen removal by Sulfammox being more than NirAnammox. The relative abundance of dominant bacteria of the Sulfammox were 10–20 times that of Candidatus Kuenenia (NirAnammox) in each reactor. Organic matter negatively affected NirAnammox, but not Sulfammox. Dissolved oxygen negatively affected both.

The increasing water pollution caused by the presence of nano- and microplastics has shown a need to pursue solutions to remediate this problem. In this work, an extracellular polymeric substance (EPS) producing freshwater Cyanothece sp. strain was exposed to nano- and microplastics. The bioflocculant capacity of the biopolymer produced was evaluated. The influence of different concentrations (1 and 10 mg L⁻¹) of polystyrene nano- and microplastics in the extracellular carbohydrates and in the EPS production was studied. The presence of nano- and microplastics induced a negative effect on the microalgal growth (of up to 47%). The results show that the EPS produced by Cyanothece sp. exhibits high bioflocculant activity in low concentrations. Also, the EPS displayed very favourable characteristics for aggregation, as the aggregates were confirmed to consist of microalga, EPS and both the nano- and microplastics. These results highlight the potential of the microalgal-based biopolymers to replace hazardous synthetic flocculants used in wastewater treatment, while aggregating and flocculating nano- and microplastics, demonstrating to be a multi-purposed, compelling, biocompatible solution to nano- and microplastic pollution.

Several harbour activities cause negative environmental impacts in the harbours’ surrounding areas, namely the degradation of air quality. This paper intends to comprehensively review the status of the air quality measured in harbour areas. The published studies show a limited number of available air quality monitoring data in harbours areas, mostly located in Europe (71%). Measured concentrations of the main air pollutants were compiled and intercompared, for different countries worldwide allowing a large spatial representativeness. The higher NO₂ and PM₁₀ concentrations were found in Europe - ranging between 12 and 107 μg/m³ and 2–50 μg/m³, respectively, while the higher concentrations of PM₂.₅ were found in Asia (25–70 μg/m³). In addition, the lower levels of SO₂ monitored in recent years suggest that current mitigation strategies adopted across Europe were very efficient in promoting the reduction of SO₂ concentrations.Part of the reviewed studies also estimated the contributions from ship emissions to PM concentration through the application of source apportionment methods, with an average of 5–15%. In some specific harbour areas in Asia, ships can contribute up to 7–26% to the local fine particulate matter concentrations. This review confirms that emissions from the maritime transport sector should be considered as a significant source of particulate matter in harbour areas, since this pollutant concentrations are frequently exceeding the established standard legal limit values. Therefore, the results from this review boost the implementation of mitigation measures, aiming to reduce, in particular, particulate matter emissions.

Hard coal is the predominant energy source in Poland. The unavoidable consequence of coal combustion is the production of huge amounts of ash which can be concentrated in radionuclides. The ashes from coal combustion are utilized or stored and may affect the quality of the environment. Therefore, the estimation of radionuclides in hard coal and by-products is of crucial importance. The analyzed samples included ashes produced in ash furnaces, power plants and individual home furnaces operating in the Upper Silesian Industrial Region, Southern Poland, during the hard coal burning. This paper presents radioactivity concentrations of ²²⁸Ra, ²²⁶Ra and ⁴⁰K in hard coal, bottom and fly ash samples from Polish coal-fired power plants obtained during various technological coal combustion processes and generated in individual domestic furnaces, determined using the HPGe gamma spectrometry technique. The measurements of ²³⁴,²³⁸U concentrations were performed after sample preparation using alpha-particle spectrometer. The concentrations of the obtained radionuclides differ greatly in the fly and bottom ash samples. The lowest concentrations of ²²⁶Ra, ²²⁸Ra, ²³⁴U, ²³⁸U were observed in bottom ashes from the co-firing of hard coal and biomass in a fluidized-bed furnace, whereas the highest concentrations of ²²⁶Ra (163 ± 6 Bq/kg), ²²⁸Ra (100 ± 2 Bq/kg) isotopes were found in the ashes from individual household furnaces. This means that both the feed coal type and combustion techniques have a direct impact on the concentration of radionuclides in ash. Hard coal silt samples may be enriched in radionuclides and the radioactive equilibrium between ²²⁶Ra and ²³⁸U even in the case of coal is not always achieved. The concentrations of the analyzed isotopes in ashes are 5-7-fold higher than in feed coal. Given that combustion by-products are utilized as construction products, it should be noted that for some ash samples, the radiological hazard indices approach or exceed the maximum permitted levels.