Transgenic maize expressing the Cry1Ab and Cry2Ab protein simultaneously from Bacillus thuringiensis (Bt-maize) has been grown for farm-scale study to investigate its potential impact to non-target arthropod (NTA). The trials were conducted between Bt maize 2A-7 and its parental line (B73-329) in Beijing, China, over 3 years. Richness (C), Shannon index (H), Pielou index (J), Simpson index (D), and Bray-Curtis index were used to evaluate the population dynamics and biodiversity of the dominant arthropods from per 50 plants in crop field. The mainly abundant groups were Aphidoidea, Araneae, Coccinellidae, Anthocoridae, and Thripidae which represented about 90% of the total number of NTA. Although the abundance of NTA varied from year to year, there is no significant difference between Bt maize and non-Bt maize field. Fluctuations were found at individual sample dates, but the trend of these descriptors remained consistent. Further analysis showed the biodiversity indexes of the dominant arthropods C, H, J, D, and Bray-Curtis dissimilarity between Bt maize producing Cry1Ab and Cry2Ab toxin simultaneously and its parental line had no significant difference except for some sampling dates. These results suggested that Bt maize is compatible with the NTAs and provides further evidence of the ecological impact of genetically modified maize.

The use of certain types of plants to determine the accumulation of HMs (heavy metals) has yielded quite consistent results in the research fields. Many researches have focused on particular types of HMs due to their common presence in the air (Pb, Cd, Ni, Co, Cr to name a few). However, it is equally as important to shed light on other types of HMs and the scale of their existence in our atmosphere, hence this paper. Blue spruce (Picea pungens) tree organs were used in an experiment to calculate the recent concentration of HMs. The research concentrates on Ca, Cu, and Li elements in the washed and unwashed needles, branches, and barks, and these organs were evaluated depending on the organ age. The study results showed that the concentration of the elements subjected to the research changed depending on the organ, washing status and organ age, and that the lowest concentrations of Ca and Cu elements were obtained in the barks in general. In relation to the organ age, it was found that there was an increase in the concentration of Ca with age, and that the concentration of Li element was inversely proportional to age.

Metals are widely used in modern society harming the environment; their toxicity cause environmental adverse effects to many organisms including zooplankton. This contribution employed: (a) acute and chronic toxicity tests, (b) epifluorescence image analysis, and (c) atomic absorption techniques, to analyze toxicity of four trace (copper, iron, nickel, and zinc), and one non-trace metals (mercury) on the freshwater rotifer Euchlanis dilatata. This work integrated results of Bioconcentration Factors (BCF’s), sites of entry and accumulation and to determine mechanisms of uptake and toxicity of these five metals of the freshwater rotifer Euchlanis dilatata. This integral analysis enhanced our understanding of knowledge on: (a) the toxicity mechanisms, (b) sites of metal entry and concentration inside the rotifer, (c) bioconcentration and body burdens. As expected, Hg the non-trace metal used here, was the most toxic. Our results suggest that the toxicity is ameliorated in the rotifer by selecting feeding avoiding the most toxic particles and reducing adverse effects on reproduction, until mortality per se reduces reproduction. The chronic effect on ingestion rate was quite sensitive for all metals whereas reproduction was slightly affected. The combination of acute and chronic tests and determination of BCF’s for each metal allowed calculation of the acute and chronic body burdens. Body burdens again confirmed that mercury was the most toxic metal of the five employed here.

The number and production capacities of greenhouse farms have been increased across the globe, driven by an effort for addressing food security problems related to the rapid population growth and the effects of climate change. As a result, there was a large increase in the number of greenhouse farm workers who are typically involved in chemical preparations and pesticide sprayings, crop harvesting, and greenhouse maintenance activities. Considering the enclosed architecture of the greenhouse farm design and the frequent application of pesticides, the objective of this review was to characterize pesticide exposure levels and resultant health effects among greenhouse farm workers. While most health assessment studies were mainly based on self-reported symptoms, this review showed limited epidemiological and clinical studies on the assessment of the health effects of pesticide exposure on greenhouse workers’ health. Reproductive disorders, respiratory symptoms, neurological symptoms, and skin irritations were the most reported health effects among greenhouse farm workers. Additionally, there were limited studies on respirable pesticide-borne fine and ultrafine particulate matters in greenhouse farms. Ventilation systems and indoor environmental conditions of greenhouse farms were not designed according to specifications of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Among recommendations provided, long-term exposure assessments of pesticide effects on children born by greenhouse farm workers should be considered in future research. Also, compliance with ASHRAE indoor ventilation and environmental standards will be very important in reducing pesticide exposure and health effects among greenhouse farm workers.

Radiation-induced degradation of chlorobenzene was conducted at 0.1, 0.4, 0.5, 0.7, and 1.0 mmol/dm³ concentrations in aerated environment and at 1.0 mmol/dm³ in oxygen-free and N₂O-saturated solutions. The results demonstrated that the elimination of chloride is important when the solution is oxygen free, because the [Formula: see text] attacks at the ipso position of the chloro group produces hydrochloric acid. The degradation was affected to a large extent by the concentration and to a lesser extent by the presence or absence of oxygen in the solutions which were irradiated. Thereby, the degradation occurred faster in the solutions with air and without oxygen and more slowly in the saturated solution with N₂O. Some by-products were identified using an HPLC-UV-mass system. In addition, it was found that there is a linear correlation between the ln C/C₀ and the dose, indicating that the radiolytic degradation followed pseudo-first-order reaction kinetics. The radiolytic oxidation was followed by the chemical oxygen demand (COD) test. The COD decreases when the solute concentration increases. The COD results were for a 0.47 mmol/dm³ of 5.94 mg O₂ dm⁻³ kGy⁻¹ and for 0.09 mmol/dm³ of 7.45 mg O₂ dm⁻³ kGy⁻¹.

Soil heavy metal pollution, especially lead (Pb) and arsenic (As), is a global issue that requires urgent attention. In the present study, phosphate-modified ferric-based material (PFM) was used to remedy Pb and As co-contaminated soil. The remediation potential of PFM on Pb and As co-contaminated soil was studied by static culture experiments, and the effect on maize (Zea mays L.) seedling growth was studied using pot experiments. The results showed that the bioavailability of Pb and As in the soil and their accumulation in the seedlings were reduced when PFM was added to the soil. At 2–6 wt% PFM, the remediation rates of Pb and As reached 57%–82% and 62%–76%, respectively, and their accumulation in the seedlings decreased by 27.8%–68% and 55.6%–70%. The optimal amount of PFM was 4 wt% of the soil. There was a linear correlation between the amount of DTPA-extractable Pb or NaHCO₃-extractable As in the soil and the amount of Pb or As accumulated by the seedlings. The correlation coefficients of Pb and As reached 0.7690–0.8166 and 0.9982–0.9779. Seedling growth was also promoted. Compared with the controls, the seedling emergence rate increased by 1.4%–4%, plant height increased by 4.1%–12.4%, plant weight increased by 29.6%–37%, and the root length increased by 5%–52%. In summary, PFM offers an environmentally friendly approach with excellent potential for the remediation of Pb and As co-contaminated soil.

The effluents of municipal wastewater treatment plant (WWTP) contain excessive nitrogen and phosphorus compared with the concentration in rivers or lakes. To reduce the pollutant load placed on aqueous environments, constructed wetland (CW) technology has been widely applied to advanced wastewater treatment. Packing substrates in CW could remove various pollutants. Steel slag, yellow earth, kaolin, volcanic rock, anthracite, and ceramsite could effectively remove phosphorus (P); volcanic rock, ceramsite, zeolite, yellow earth, manganese sand, and activated carbon have an affinity for ammonia nitrogen (NH₄⁺-N). After 24 h reactions with the WWTP standard 1B synthetic wastewater, four packing substrates, i.e., volcanic rock and anthracite (1:1), volcanic rock and yellow earth (2:1), zeolite and yellow earth (2:1), and manganese sand and activated carbon (1:3), could remove over 56% and 30% of NH₄⁺-N and phosphorus respectively. In addition, anthracite and volcanic rock (1:3), anthracite and activated carbon (1:40), anthracite and manganese sand (1:5), and anthracite and zeolite (1:4) effectively purified NH₄⁺-N and phosphorus in secondary WWTP effluent, with removal efficiency exceeding 39% and 27%, respectively. A sequential experiment was performed to optimize packing substrates ratios in CW with volcanic rock and anthracite, ceramsite and yellow earth, and manganese sand and activated carbon. When the quantity of the substrate was doubled, most packing substrates adsorb more than 50% phosphorus and NH₄⁺-N of the standard 1B WWTP synthetic wastewater. Considering the removal efficiency of packing substrates on phosphorus and NH₄⁺-N, it is suggested that manganese sand and activated carbon (1:3), volcanic rock and anthracite (2:1), and yellow earth are appropriate substrates for CW in WWTP effluent advanced treatment.

Nutrient retention is an important process in lake nutrient cycling of lakes and can mitigate lake eutrophication. However, little is known about temporal lake nutrient retention efficiency and it varies due to changes in hydrological, ecological, and nutrient inputs to lake waters. Quantitative information about seasonal lake N and P retention is critical for developing strategies to reduce eutrophication in lake systems. This study investigated TN and TP retention efficiencies and retention masses using water and mass balance calculations, and statistically analyzed the seasonal variability of nutrient retention in Lake Chaohu, China, from 2014 to 2018. Lake Chaohu experienced large amounts of external loads inputs (23.2 g N m⁻² year⁻¹ and 1.3 g P m⁻² year⁻¹), and approximately 58% TN and 48% TP were retained annually. The lake acted more as a sink for N than for P. The mean annual TP retention efficiency decreased (P < 0.05) over the study period, indicating that TP retention capacity was gradually exceeded. Seasonal variability of TN and TP retention efficiency was high and ranged from − 18.7 to 144.1% and from − 58.8 to 170.7%, respectively, over the five study years. The internal P loads over the study period were equivalent to roughly 9% of the total external loads. The annual nutrient retention efficiency of TN and TP increased with hydraulic residence time, while water temperature was an essential factor for the contrasting seasonal variation patterns of TN and TP retention efficiencies.

The carbon recovery from organic space waste by supercritical water oxidation (SCWO) was studied to support resource recovery in a regenerative life support system. Resource recovery is of utmost importance in such systems which only have a limited total amount of mass. However, the practical waste treatment strategies for solid space wastes employed today are only storing and disposal without further recovery. This work assesses the performance of SCWO at recovering organic wastes as CO₂ and water, to discuss the superiority of SCWO over most present strategies, and to evaluate the different SCWO reactor systems for space application. Experiments were carried out with a batch and a continuous reactor at different reaction conditions. The liquid and gas products distribution were analyzed to understand the conversion of organics in SCWO. Up to 97% and 93% of the feed carbon were recovered as CO₂ in the continuous and the batch reactor, respectively. Residual carbon was mostly found as soluble organics in the effluent. Compared with the batch reactor, the continuous reactor system demonstrated a ten times higher capacity within the same reactor volume, while the batch reactor system was capable of handling feeds that contained particulate matter though suffering from poor heat integration (hence low-energy efficiency) and inter-batch variability. It was concluded that SCWO could be a promising technology to treat solid wastes for space applications. A continuous reactor would be more suitable for a regenerative life support system.

This work investigates the feasibility of co-mechanochemical treatment of oil-contaminated drill cuttings (OCDC), circulation fluidized bed combustion (CFBC) fly ash, and quicklime to prepare non-sintered lightweight aggregates (NSLWAs). The NSLWAs with high cylinder compressive strength and low water absorption could be obtained under the condition of optimal water addition and appropriate steam-curing temperature, as well as steam-curing time. Co-mechanochemical treatment could enhance the pozzolanic reactivity of CFBC fly ash effectively, which is beneficial to the strength development of NSLWAs. Moreover, co-mechanochemical treatment also can degrade the petroleum hydrocarbon of OCDC, greatly reducing the leaching concentrations of total petroleum hydrocarbons (TPH) of NSLWAs. The final leaching concentrations of TPH are much lower than the requirements of Chinese National Standard GB 31571–2015. Graphical abstract