Environmental Chemistry Letters最新文献

Di-2-ethylhexyl phthalate is a plasticizer of health concern due to its presence in the environment and its association with health issues such as metabolic and neurodevelopment disorders. We review the potential hazards and mechansims of di-2-ethylhexyl phthalate exposure on the metabolism and neurodevelopment. Di-2-ethylhexyl phthalate is closely linked to metabolic diseases such as obesity and diabetes, interfering with adipocyte differentiation and lipid metabolism through multiple pathways, thereby disrupting the energy balance. Di-2-ethylhexyl phthalate is also altering the pancreatic function and glucose metabolism. In terms of neurodevelopment, exposure to di-2-ethylhexyl phthalate is associated with neurological abnormalities, crossing the blood–brain barrier and directly impacting the central nervous system. Early exposure may lead to abnormalities in neuronal migration, synapse formation, and neural connectivity, potentially resulting in cognitive and behavioral consequences. Di-2-ethylhexyl phthalate exposure, particularly during childhood and adolescence, may have long-term effects on learning, memory, and behavior.

The worldwide contamination of waters and food by herbicides is a major health issue, yet the toxic effects of herbicides to non-target organisms and ecosystems have been poorly summarized. Here we review the effects of herbicides belonging to the groups of chloroacetanilides, imidazolinones, sulfonylureas, and pyrimidinylcarboxylic, on small invertebrates, high vertebrates, plants, and the surrounding ecosystems. We describe toxicity in terms of behavioural changes, molecular biosynthesis, endocrine disruption, immunological responses, enzymatic alteration, and reproductive disorders. Strategies to decrease toxic effects are also presented. We observe widespread toxicity threats in amphibians and major aquatic species. Each herbicide group displays a different toxicity risk. For instance, chloroacetanilides display higher risks to soil, aquatic, algal, cyanobacteria, and terrestrial species, whereas alachlor, acetochlor, and metolachlor are highly carcinogenic to humans. Most imidazolinone herbicides cause phytotoxicity in non-target and succeeding crops. Sulfonyl-urea herbicides are severely toxic to soil microbes and succeeding crops. Pyrimidinylcarboxy herbicides are more toxic to soil microbes, aquatic species, and rats.

The world energy consumption has increased by + 195% since 1970 with more than 80% of the energy mix originating from fossil fuels, thus leading to pollution and global warming. Alternatively, pyrolysis of modern biomass is considered carbon neutral and produces value-added biogas, bio-oils, and biochar, yet actual pyrolysis processes are not fully optimized. Here, we review the use of machine learning to improve the pyrolysis of lignocellulosic biomass, with emphasis on machine learning algorithms and prediction of product characteristics. Algorithms comprise regression analysis, artificial neural networks, decision trees, and the support vector machine. Machine learning allows for the prediction of yield, quality, surface area, reaction kinetics, techno-economics, and lifecycle assessment of biogas, bio-oil, and biochar. The robustness of machine learning techniques and engineering applications are discussed.

Many organic pollutants are chemically stable and thus cannot be degraded by classical wastewater treatment techniques. To solve this issue, ozone-based advanced oxidation processes using hydroxyl radicals with strong oxidation ability have been recently developed. Here we review hydroxyl radicals in ozone-based advanced oxidation processes with focus on reaction characteristics, generation, detection, and quantitation of hydroxyl radicals. Hydroxyl radicals are generated using ozone micro/nano-bubbles, peroxymonosulfate-activated ozone, ozone coupled with Fenton oxidation, electro-peroxone, or catalytic ozonation. Hydroxyl radicals are detected by electron paramagnetic resonance and quenching experiments. We also present applications in wastewater treatment and reactor design. Ozone-based advanced oxidation combines direct oxidation by ozone molecules and indirect oxidation by reactive oxygen species; regulating these two pathways remains challenging. The generation of hydroxyl radicals depends on the environmental matrix and on the chemical structure, properties, and ozone reactivity of contaminants. Chain reactions among reactive oxygen species induce contradictions during the analysis of results obtained by electron paramagnetic resonance, quenching techniques, and probe methods.

Nitrogen pollution is a global issue impacting ecosystems, climate change, human health, and the economy. The challenge to reduce nitrogen pollution as a priority highlights the wastewater treatment system an important point of control. Coagulation, a common water treatment process, has a positive impact on the overall treatment process but often struggles to address nitrogen pollution effectively. Our study introduces a novel magnetic seed to enhance coagulation in treating nitrogen pollution, offering a new solution for the global water treatment industry. We focus on the efficiency, mechanistic detail, and recovery potential of a magnetic zirconium tannate in treating real-world wastewater nitrogen under coagulation conditions. Results show that 9 g/L of magnetic zirconium tannate effectively removes ammonia nitrogen, organic nitrogen, and total nitrogen from five different wastewater types. For low-concentration wastewater with ammonia nitrogen below 20 mg/L and organic nitrogen below 5 mg/L, removal rates reach up to 100%. For high-concentration wastewater with ammonia nitrogen below 98 mg/L and organic nitrogen below 86 mg/L, the maximum removal rate is 59% for ammonia nitrogen and 88% for organic nitrogen. Spectral analysis reveals that magnetic zirconium tannate adsorbs nitrogen compounds in water through both hydrogen bonding and electrostatic interactions, achieving excellent treatment outcomes. It can be efficiently recovered without using complex organic eluents and is easily separated from the flocculate. This technology offers non-disruptive supplement for current treatment approaches to meet the global nitrogen pollution challenge head on.

Fiber-reinforced polymer composites, reaching a production of approximately 2.56 million tons in 2023 in Europe, display unique properties, yet they are disposed of at their end of service by conventional methods such as landfill and incineration. Here, we review the recycling of fiber-reinforced polymer wastes in the construction industry, with emphasis on fiber-reinforced polymer composites, recycling methods, and applications of carbon and glass fiber polymer composites in civil engineering. Recycling methods include mechanical, thermal, and chemical techniques. Applications comprise the use in fine fillers, coarse and fine aggregates, macro-fibers, alkali-activated materials, geopolymers, asphalt composites, and cement composites. We discuss workability, mechanical properties including compressive, flexural and tensile properties, durability, and surface modification. Future applications include three-dimensional concrete printing, self-sensing cement composites, self-heating and energy harvesting cement composites, and electromagnetic shielding. We propose a waste management hierarchy, considering the source of composites and their intended applications, to improve circularity.

Microbial electric syntrophy, involving direct electron transfer between electron-donating strains and electron-accepting strains, could reduce more than 50% of methane emissions and remove 90% of nitrate pollution in some wastewaters. Microbial electric syntrophy is also a key natural process allowing the survival of bacteria in harsh environmental conditions. Here we review natural and artificial cases of interspecies electron transfer in microbial syntrophy, with emphasis on methane production, electroactive bacteria, methanogens, anaerobic methane-oxidizing consortia, Geobacter species, phototrophic bacteria, co-cultures, anaerobic digestion, environmental remediation and microbial electrosynthesis. Environmental remediation includes nitrogen removal, reductive dechlorination and pollutant degradation. Microbial electrosynthesis can be used for carbon dioxide reduction. Conductive proteins and materials, and light-assisted electron transfer contribute to the direct interspecies electron transfer.

The circular economy requires advanced methods to recycle waste matter such as ammonia, which can be further used as a fuel and a precursor of numerous value-added chemicals. Here, we review methods for the recovery of ammonia from wastewater with emphasis on biological and physicochemical techniques, and their applications. Biological techniques involve nitrification, denitrification, and anammox processes and the use of membrane bioreactors. Physicochemical techniques comprise adsorption, membrane filtration, ion exchange, chemical precipitation, ammonia stripping, electrochemical oxidation, photocatalytic oxidation, bioelectrochemical systems, and membrane hybrid systems. We found that nitrification and anammox processes in membrane bioreactors stand out for their cost-effectiveness, reduced sludge production, and energy efficiency. The use of struvite precipitation is an efficient, environmentally friendly, and recyclable method for ammonia removal. Membrane hybrid systems are promising for ammonia recovery, nutrient concentration, and wastewater treatment, with applications in fertilizer production and water purification. Overall, nitrogen removal ranges from 28 to 100%, and nitrogen recovery ranges from 9 to 100%.

Total plastic production is expected to reach 33 billion tons by 2050, and microplastic emissions from effluents to the environment range from 0.46 million to 140 billion tons. Microplastic distribution and toxicological effects are actually poorly known. Here we review microplastic pollution with emphasis on their environmental distribution, their aging, their analysis in the environment and living organisms, their toxicity alone or combined with other contaminants, and their mitigation techniques. We present microplastic distribution in soil, water, and the atmosphere. Microplastic aging is controlled by physical, chemical, and biological factors. Model organisms of microplastic exposure include zebrafish, earthworms, Caenorhabditis elegans, and Arabidopsis thaliana. Microplastic exposure to humans could induce gastrointestinal, pulmonary, reproductive, and cardiovascular toxicity, and neurotoxicity. We discuss the combined toxicity of microplastics with organic pollutants, heavy metals, endocrine disruptors, and antibiotics. Fourier transform infrared spectroscopy and Raman spectroscopy are currently the most commonly used techniques for microplastic analysis.