Surface and water bodies in many parts of the world are affected due to eutrophication, contamination and depletion. The approach of wastewater treatment using algae for eliminating nutrients and other pollutants from domestic wastewater is growing interest among the researchers. However, sustainable treatment of the wastewater is considered to be important in establishing more effective nutrient and pollutant reduction using algal systems. In comparison to the conventional method of remediation, there are opportunities to commercially viable businesses interest with phycoremediation, thus by achieving cost reductions and renewable bioenergy options. Phycoremediation is an intriguing stage for treating wastewater since it provides tertiary bio-treatment while producing potentially valuable biomass that may be used for a variety of applications. Furthermore, the phycoremediation provides the ability to remove heavy metals as well as harmful organic substances, without producing secondary contamination. In this review, the role of microalgae in treating different wastewaters and the process parameters affecting the treatment and future scope of research have been discussed. Though several algae are employed for wastewater treatment, species of the genera Chlamydomonas, Chlorella, and Scenedesmus are extensively utilized. Interestingly, there is a vast scope for employing algal species with high flocculation capacity and adsorption mechanisms for the elimination of microplastics. In addition, the algal biomass generated during phycoremediation has been found to possess high protein and lipid contents, promising their exploitation in biofuel, food and animal feed industries.

Biomass burning, a recurring global phenomenon is also considered an environmental menace, making headlines every year in India with onset of autumn months. Agriculture is demographically the broadest economic sector and plays a significant role in the overall socio-economic fabric of India. Hence, disposal of crop residue is done mainly by burning leading to deterioration of air quality. Residue burning in parts of India is blamed for changing air quality in nearby cities. The spatial distribution of these emissions has always been a challenge due to various data constraints. We hereby present a comprehensive spatially resolved seasonal high resolution gridded (∼10 km × ∼10 km) emission inventory of major pollutants from crop residue burning source in India for the latest year 2018. The winter months contributes almost around ∼50% of total emission followed by summer (∼48%), which is the prime cause of changing air quality in nearby cities. Among all the crops; rice, wheat, maize and sugarcane accounts ∼90% of total PM₁₀ load in the country. The estimated emission for PM₂.₅, PM₁₀, BC and OC, CO, NOx, SO₂, VOC, CH₄ and CO₂ are found to 990.68 Gg/yr, 1231.26 Gg/yr, 123.33 Gg/yr, 410.99 Gg/yr, 11208.18 Gg/yr, 484.55 Gg/yr, 144.66 Gg/yr, 1282.95 Gg/yr, 785.56 Gg/yr and 262051.06 Gg/yr respectively. The cropping pattern and its role in different geographic regions are analysed to identify all potential emission hotspots regions scattered across the country. The developed gridded emissions inventory is envisaged to serve as an important input to regional atmospheric chemistry transport model to better quantify its contribution in deteriorating air quality in various regions of India, paving the way to policy makers to better plan the mitigation and control strategies. The developed fundamental tool is likely to be useful for air quality management.

Cadmium (Cd) is an occupational and environmental pollutant, which mainly causes nephrotoxicity by damaging renal proximal tubular cells. To evaluate the effects of Cd on pyroptosis and the relationship between pyroptosis and apoptosis in duck renal tubular epithelial cells, the cells were cultured with 3CdSO₄·8H₂O (0, 2.5, 5.0, or 10.0 μM Cd), N-acetyl-L-cysteine (NAC) (100.0 μM), Z-YVAD-FMK (10.0 μM) or the combination of Cd and NAC or Z-YVAD-FMK for 12 h, and then cytotoxicity was assessed. The results evidenced that Cd significantly increased the releases of interleukin-18 (IL-18) and interleukin-1β (IL-1β), lactate dehydrogenase (LDH) and nitric oxide (NO), relative conductivity and cellular reactive oxygen species (ROS) level. Simultaneously, Cd also markedly upregulated NLRP3, Caspase-1, ASC, NEK7, IL-1β and IL-18 mRNA levels and NLRP3, Caspase-1 p20, GSDMD and ASC protein levels. Additionally, NAC notably improved the changes of above indicators induced by Cd. Combined treatment with Cd and Z-YVAD-FMK remarkably elevated Bcl-2 mRNA and protein levels, inhibited p53, Bax, Bak-1, Cyt C, Caspase-9 and Caspase-3 mRNA levels and p53, Bax, Bak-1, Caspase-9/cleaved Caspase-9 and Caspase-3/cleaved Caspase-3 protein levels, increased mitochondrial membrane potential (MMP), decreased apoptosis ratio and cell damage compared to treatment with Cd alone. Taken together, Cd exposure induces duck renal tubular epithelial cell pyroptosis through ROS/NLRP3/Caspase-1 signaling pathway, and inhibiting Caspase-1 dependent pyroptosis attenuates Cd-induced apoptosis.

An experimentally induced three-dimensional petroleum seepage flume was used to investigate its migration in heterogeneous soil layers and a method for monitoring resistivity was adopted, under conditions of fluctuating water levels and rainfall. The corresponding mechanisms were then analyzed based on the resistivity characteristics and combined with three-dimensional inversion images. Finally, physical and chemical property analysis was conducted to verify the results of resistivity monitoring. The results demonstrated that: (1) In the process of natural oil leakage, the variation of soil resistivity presents a concave shape in the resistivity profile. Thus, oil migration exhibited the following patterns. At first, circular migration front was dominant in a vertical direction. Subsequently, after vertical migration was impeded, lateral migration was dominant. As the crude oil gradually accumulated, the migration front broke through the limitation of lithologic interface and continued vertically. (2) By comparing the two resistivity monitoring methods, namely the Wenner and Pole-pole methods, it was demonstrated that the inversion resistivity measured by Wenner method was closer to the true resistivity, and the resistivity variations were more distinguishable. (3) The resistivity inversion profile demonstrated that the low resistivity anomaly of the crude oil leakage area was related to the low water content of the soil layer in the test area. (4) Fluctuations in water level increased the diffusion range of crude oil beyond the original pollution source area, especially horizontally. (5) Percolation of rainfall caused the water level to rise, and the crude oil was evenly distributed in the soil layers above the capillary zone. (6) Through sample analysis and verification, it was demonstrated that the resistivity method can accurately and intuitively present the characteristics of crude oil migration. These results provide theoretical support for the rapid determination of the migration range and characteristics of crude oil in heterogeneous soil layers.

Urbanisation of riverine landscape is an increasing threat to the functionality of river ecosystems. In this study, we identify and classify macroinvertebrates indicator signature traits and ecological preferences.We hypothesised that urban pollution would differentially influence the distribution of macroinvertebrate traits and ecological preferences along a gradient of water quality deterioration. Hence, we identified and classified potential biological indicators traits and ecological preferences that were deemed tolerant of or sensitive to urban pollution gradient in the Niger Delta region of Nigeria. Physico-chemical variables (water temperature, depth, flow velocity, dissolved oxygen, biochemical oxygen demand, electrical conductivity (EC), nitrate, phosphate), and macroinvertebrates were collected from 2008 to 2012 seasonally during the wet and dry seasons once in a month in 11 stations in eight river systems. The results based on RLQ, fourth-corner and Kruskal-Wallis analyses indicate that traits/ecological preferences such as tegumental/cutaneous respiration, cased/tubed body armouring, a preference for silty water, bivoltinism, burrowing and a high tolerance for oxygen depletion, were statistically significantly associated with the heavily impacted stations. These traits were positively correlated with physico-chemical variables such as EC, nitrate and phosphate indicative of urban pollution. On the other hand, traits/ecological preferences such as permanent attachment, crawling, swimming, univoltinism and a moderate sensitivity to oxygen depletion were associated with the least impacted stations and were negatively correlated with physico-chemical variables indicative of urban pollution. Overall, the observed differential responses of traits and ecological preferences to urban pollution along a gradient of water quality impairment suggest that traits and ecological preferences can serve as useful biological indicators and thus supports the growing evidence of the utility of the trait-based approach.

Cadmium (Cd), which is considered a carcinogenic metal, promotes breast cancer (BC) progression, but the precise mechanism remains unclear. Herein, MCF-7 and T47-D cells were treated with 0.1, 1, and 10 μM cadmium chloride (CdCl₂) for 24, 48 and 72 h. In our study, Cd exposure significantly accelerated the proliferation, migration and invasion of MCF-7 and T47-D cells. Notably, Cd inhibited autophagic flux by suppressing ATG5-dependent autophagosome formation but had no significant effect on autophagosome-lysosome fusion and lysosomal function. The genetic enhancement of autophagy through ATG5 overexpression suppressed the Cd-mediated increases in proliferation, migration and invasion, which indicated a carcinogenic role of autophagy impairment in Cd-exposed BC cells. GSEA and GeneMANIA were utilized to demonstrate that the Cd-induced decrease in ACSS2 expression mechanistically inhibited ATG5-dependent autophagy in BC cells. Importantly, ACSS2 overexpression increased the level of H3K27 acetylation in the promoter region of ATG5, and this result maintained autophagic flux and abolished the Cd-induced increases in proliferation, migration and invasion. We also verified that the expression of ACSS2 in BC tissues was low and positively related to ATG5 expression. These findings indicated that the promoting effect of Cd on BC cell proliferation, migration and invasion through the impairment of ACSS2/ATG5-dependent autophagic flux suggests a new mechanism for BC cell proliferation and metastasis stimulated by Cd.

The combined use of nano-TiO₂ with cementitious materials offers an environmentally-friendly way to combat the air pollution problem. However, a trade-off between a high efficiency and a robust weathering resistance has often to be made for most of the attempted nano-TiO₂ incorporation methods. This paper developed a simple and effective “spraying” method to coat nano-TiO₂ particles on the surface of concrete surface layers (CSL). The results showed that the NOₓ removal rate of the samples increased with an increase in both the concentrations of nano-TiO₂ solutions and the number of times of the spraying action. And the conditions for preparation of the Spray AB (the CSL were first sprayed with the 30 g L⁻¹ TiO₂-solution 20 times, followed by mechanical compaction, and for another 20 times after the compaction) were found to be optimal in terms of NOₓ removal performance and weathering resistance. The Spray AB was superior to the 5% TiO₂-intermixed samples with respect to photocatalytic NOₓ removal ability. Compared with TiO₂-dip-coated samples, the Spray AB samples had better and robust weathering resistance. A case study on the factory-fabricated green Eco-blocks (produced by the laboratory-developed spray method and the conventional intermix method) was performed. Examination and comparison on their respective photocatalytic NOₓ removal further verified the advantages of the spray method over the intermix method.

Recent studies suggests that air pollution, from among others road traffic, can influence growth and development of the human foetus during pregnancy. The effects of air pollution from heavy industry on birth outcomes have been investigated scarcely.Our aim was to investigate the associations of air pollution from heavy industry on birth outcomes.A cross-sectional study was conducted among 4488 singleton live births (2012–2017) in the vicinity of a large industrial area in the Netherlands. Information from the birth registration was linked with a dispersion model to characterize annual individual-level exposure of pregnant mothers to air pollutants from industry in the area. Associations between particulate matter (PM₁₀), nitrogen oxides (NOX), sulphur dioxide (SO₂), and volatile organic compounds (VOC) with low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA) were investigated by logistic regression analysis and with gestational age, birth weight, birth length, and head circumference by linear regression analysis.Exposures to NOX, SO₂, and VOC (per interquartile range of 1.16, 0.42, and 0.97 μg/m³ respectively) during pregnancy were associated with LBW (OR 1.20, 95%CI 1.06–1.35, OR 1.20, 95%CI 1.00–1.43, and OR 1.21, 95%CI 1.08–1.35 respectively). NOX and VOC were also associated with PTB (OR 1.14, 95%CI 1.01–1.29 and OR 1.17, 95%CI 1.04–1.31 respectively). Associations between exposure to air pollution and birth weight, birth length, and head circumference were statistically significant. Higher exposure to PM₁₀, NOX, SO₂ and VOC (per interquartile range of 0.41, 1.16, 0.42, and 0.97 μg/m³ respectively) was associated with reduced birth weight of 21 g to 30 g.The 90th percentile industry-related PM₁₀ exposure corresponded with an average birth weight decrease of 74 g.

Ambient ozone (O₃) pollution has become a big issue in China. Recent studies have linked long- and short-term O₃ exposure to several public health risks. In this study, we (1) characterize the long-term and short-term O₃-attributed health metric in China from 2015 to 2019; (2) estimate the surface O₃ trends; and (3) quantify the long-term and short-term health impacts (i.e. all-cause, cardiovascular and respiratory mortality) in 350 urban Chinese cities. In these 5-years, the national annual average of daily maximum 8 h average (AVGDMA8) O₃ concentrations and warm-season (April–September) 4th highest daily maximum 8 h average (4DMA8) O₃ concentrations increased from 74.0 ± 15.5 μg/m³ (mean ± standard deviation) to 82.3 ± 12.0 μg/m³ and 167 ± 37.0 μg/m³ to 174 ± 30.0 μg/m³ respectively. During this period, the DMA8 O₃ concentration increased by 1.9 ± 3.3 μg/m³/yr across China, with over 70% of the monitoring sites showing a positive upward trend and 19.4% with trends >5 μg/m³/yr. The estimated long-term all-cause, cardiovascular and respiratory premature mortalities attributable to AVGDMA8 O₃ exposure in 350 Chinese cities were 181,000 (95% CI: 91,500–352,000), 112,000 (95% CI: 38,100–214,000) and 33,800 (95% CI: 0–71,400) in 2019, showing increases of 52.5%, 52.9% and 54.6% respectively compared to 2015 levels. Similarly, short-term all-cause, cardiovascular and respiratory premature mortalities attributed to ambient 4DMA8 O₃ exposure were 156,000 (95% CI: 85,300–227,000), 73,500 (95% CI: 27,500–119,000) and 28,600 (95% CI: 14,500–42,800) in 2019, increases of 19.6%, 19.8% and 21.2% respectively compared to 2015. The results of this study are important in ascertaining the effectiveness of recent emission control measures and to identify the areas that require urgent attention.

Hydrochar (HC) serves as a promising adsorbent to remove the cadmium from aqueous solution due to porous structure. The chemical aging method is an efficient and easy-operated approach to improve the adsorption capacity of HC. In this study, four chemical aging hydrochars (CAHCs) were obtained by using nitric acid (HNO₃) with mass fractions of 5% (N5-HC), 10% (N10-HC), and 15% (N15-HC) to age the pristine HC (N0-HC) and remove the Cd²⁺ from the aqueous solution. The results displayed that the N15-HC adsorption capacity was 19.99 mg g⁻¹ (initial Cd²⁺ concentration was 50 mg L⁻¹), which increased by 7.4 folds compared to N0-HC. After chemical aging, the specific surface area and oxygen-containing functional groups of CAHCs were increased, which contributed to combination with Cd²⁺ by physical adsorption and surface complexation. Moreover, ion exchange also occurred during the adsorption process of Cd²⁺. These findings have important implications for wastewater treatment to transform the forestry waste into a valuable adsorbent for Cd²⁺ removal from water.