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The large-scale emissions of airborne particulates from burning of agricultural residues particularly over the upper Indo-Gangetic Plain (IGP) have often been associated with frequent formation of haze, adverse health impacts, modification in aerosol climatology and thereby aerosols impact on regional climate. In this study, short-term variations in aerosol climatology during extreme biomass burning emissions over IGP, and thereby to regional climate were investigated. Size-segregated particulate concentration was initially measured and submicron particles (PM1.1) were found to dominate particulate mass within the fine mode (PM2.1). Particulate bound water-soluble ions were mainly secondary in nature, primarily composed of sulfate and nitrate. There was evidence of gaseous NH3 dominating neutralization of acidic aerosol species (SO42-) in submicron particles, in contrast to crustal dominating neutralization in coarser particulates. Variation in black carbon mass ratio was found to be influenced by local sources, while sudden increase in concentration was consistent with high Delta-C, referring to biogenic emissions. Influence of biomass burning emissions were established using specific organic (levoglucosan), inorganic (K+ and NH4+) and satellite (UV Aerosol Index, UVAI) tracers. Levoglucosan was the most abundant within submicron particles (649±177 ng m-3), with a very high ratio (>50) against other anhydrosugars, indicating exclusive emissions from burning of agriculture residues. Temporal variations of all the tracers were consistent, while NH4+ was more closely associated to levoglucosan. Spatio-temporal distribution of aerosol and few trace gases (CO and NO2) were evaluated using both space-borne active and passive sensors, and a significant increase in columnar aerosol loading (AOD: 0.98) was evident during extreme biomass burning emissions, with presence of absorbing aerosols (UVAI > 1.5) having low aerosol layer height (~1.5 km). A strong intraseasonality in aerosol cross-sectional altitudinal profile was even noted from CALIPSO, referring dominance of smoke and polluted continental aerosols across IGP. Possible transport mechanism of biomass smoke was established using cluster analysis and concentration weighted of air mass back-trajectories. Short-wave aerosol radiative forcing (ARF) was further simulated considering intraseasonality in aerosol properties, which resulted in considerable increase of atmospheric ARF (135 Wm-2) and heating rate (4.3 K day-1) during extreme biomass burning emissions compared to non-dominating one (56 Wm-2, 1.8 K day-1). We therefore conclude that influence of biomass burning emissions on regional aerosol climatology must need to be studied in much finer scale to improve parameterization of aerosol/-climate model across the region. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the variation of PM 2.5 components as well as to identify PM 2.5 sources under non-hazy weather conditions in a tropical urban city, Petaling Jaya, Malaysia. The non-hazy weather conditions were characterized by copious rainfall throughout the year and ephemeral dry periods, with no significant haze events. The PM 2.5 concentrations were recorded on the rooftop of an eight-floor building using a High Volume Sampler (HVS). The water-soluble ion (WSI), trace metal (TM) and organic and elemental carbon (OC-EC) content of PM 2.5 was determined for source apportionment using the Positive Matrix Factorization (PMF) model. Daily PM 2.5 concentrations were in the range 9.80–59.9 μgm−3. Dry weather conditions, rainfall and atmospheric stability in different seasons influenced the daily PM 2.5 variations. The maximum PM 2.5 concentration (33.1 μgm−3) was measured during the inter monsoon (INT I) season. The major constituents of PM 2.5 were OC (6.80 μgm−3, 24.4%), EC (0.700 μgm−3, 2.5%) and inorganic matter (IM) (6.6 μgm−3, 23.7%). The PMF identified eight factor profiles of PM 2.5 sources and the major source contributors were secondary inorganic aerosol (SIA), traffic and oil combustion (28.5%). We note that source characteristics of PM 2.5 were significantly modulated by seasonal factors during non-hazy weather conditions. • PM 2.5 and its potential sources under non-hazy tropical conditions were determined • The daily PM 2.5 concentration was in the range of 9.80 to 59.9 μgm−3 • Positive Matrix Factorization identified eight factor profiles of PM 2.5 sources • PM 2.5 sources ensued with more traceable pollutant groups from local activities [ABSTRACT FROM AUTHOR]

In the present study, persistence and degradation of tembotrione, a triketone herbicide, was studied in loamy soil collected from maize field. Effects of organic amendments, moistures and temperatures on tembotrione dissipation were evaluated. Soil samples were processed according to the modified QuEChERS involving dichloromethane solvent and MgSO4 without PSA. Analysis using LC-MS/MS showed >95% recoveries of tembotrione its two metabolites TCMBA and M5 from fortified soils. Tembotrione residues dissipated with time and 85.55 to 98.53% dissipation was found on 90th day under different treatments. Tembotrione dissipation increased with temperature and moisture content of the soil. Among organic amendments, highest dissipation was observed in vermicompost amended soil. Minimum and maximum half-lives of tembotrione were recorded under 35 °C (15.7 days) and air-dry (33 days) conditions, respectively. Residues of tembotrione declined with time while that of TCMBA increased steadily up to 10-45th day in different treatments and declined thereafter. Residues of M5 were not detected in our experiments. Tembotrione persistence was negatively correlated with the organic carbon (%), moisture regimes, and temperature. A good correlation between soil microbial biomass carbon and degradation was found. A two-way ANOVA indicated significant differences between the treatments at 95% confidence level (p < 0.05). [ABSTRACT FROM AUTHOR]

Aims In this study, the antifungal efficacy and phytotoxicity of silica coated porous zinc oxide nanoparticle (SZNP) were analyzed as this nanocomposite was observed to be a suitable platform for slow release fungicides and has the promise to bring down the dosage of other agrochemicals as well. Methods and results Loading and release kinetics of tricyclazole, a potent fungicide, were analyzed by measuring surface area (S BET) using Brunauer–Emmett–Teller (BET) isotherm and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. The antifungal efficacy of ZnO nanoparticle (ZNP) and SZNP was investigated on two phytopathogenic fungi (Alternaria solani and Aspergillus niger). The morphological changes to the fungal structure due to ZNP and SZNP treatment were studied by field emission-scanning electron microscopy. Nanoparticle mediated elevation of reactive oxygen species (ROS) in fungal samples was detected by analyzing the levels of superoxide dismutase, catalase, thiol content, lipid peroxidation, and by 2,7-dichlorofluorescin diacetate assay. The phytotoxicity of these two nanostructures was assessed in rice plants by measuring primary plant growth parameters. Further, the translocation of the nanocomposite in the same plant model system was examined by checking the presence of fluorescein isothiocyanate tagged SZNP within the plant tissue. Conclusions ZNP had superior antifungal efficacy than SZNP and caused the generation of more ROS in the fungal samples. Even then, SZNP was preferred as an agrochemical delivery vehicle because, unlike ZNP alone, it was not toxic to plant system. Moreover, as silica in nanoform is entomotoxic in nature and nano ZnO has antifungal property, both the cargo (agrochemical) and the carrier system (silica coated porous nano zinc oxide) will have a synergistic effect in crop protection. [ABSTRACT FROM AUTHOR]

Particulate-bound metals are reported to be toxic upon exposure through multiple pathways. In this study, both non-carcinogenic and carcinogenic health risks of diverse population age groups from the exposure of particulate-bound metals were systematically investigated considering size-segregated (PM 1.1 ; PM 2.1 ; PM > 2.1) metal concentration measured in between 2015 and 2018. Among the three particulate sizes, metal abundance was high in coarse fraction (PM > 2.1 ; mean ± SD: 43.1 ± 17.7 μgm−3) compared to fine (PM 2.1 : 18.5 ± 14.1 μgm−3) and sub-micron particulates (PM 1.1 : 11.4 ± 9.9 μgm−3). Calcium and sodium were the most abundant species irrespective of particulate sizes, accounting 53–58% of detected metal concentration. Potassium and zinc were the next two dominating species with increased abundance during biomass burning episodes. Potential sources of airborne metals were explored using advanced receptor model. Resuspensions of crustal and road dust were the most dominating sources (30–58% of metal abundance) irrespective of particulate sizes. The other recognized sources were emissions from industrial and vehicular sources, and from biomass/waste burning. Assessment of source-specific health risks indicates shared responsibility, industrial emissions (80%) being the most relevant one for carcinogenic risks. Both biomass and waste burning emissions, and vehicular emissions were found to induce non-carcinogenic risks. The non-carcinogenic health risks were mostly attributed to ingestion of metal contaminated food, especially for children (0.9–2.13 × 10−4). Carcinogenic risks, in contrast, were associated with inhalation of carcinogenic metals e.g., Cr, Pb, Co, Ni and Cd, and were high for adults (3.07–6.04 × 10−5). Health risks associated with exposure to size-segregated airborne metals were within the tolerable level (1 × 10−4) but well exceeding safe level of exposure (1 × 10−6). This emphasizes adapting more strategies and control measures of particulate sources to safeguard the health of resident population. [Display omitted] • Metal fraction in particulate mass vary with seasons particularly in PM 2.1 and PM 1.1. • Crustal sources, road dust, biomass/waste burning emissions are major sources of airborne metals. • Children were at non-carcinogenic health risks via ingestion of metal contaminated food. • Adults were at carcinogenic health risks via inhalation of airborne Cr, Co, Cd, Pb and Ni. • Industrial, biomass/waste burning and vehicular emissions were main risk inducer. [ABSTRACT FROM AUTHOR]

• Cutting-edge water filtration technology is crucial for sustainability. • MOFs are useful for pesticide sensing, monitoring, detection, and adsorption because of their modern synthesis methods and multifunctional activity. • Molecular simulations have helped scientists optimise MOF@Pesticide based system parameters. • Newer applications of MOFs exist, along with prospective research routes and challenges. Aggravated use of pesticides to intensify production and their transmigration to the aquatic environments jeopardises mother earth's ecological balance. To overcome this menace, the search for better and more efficient technologies for pesticides removal is still rambling on. In this regard, metal–organic frameworks (MOFs) have been found promising owing to their hybrid property, tunable size, greater surface area, multidimensional porosity, and functional effectiveness. With a steadily growing interest in the application of MOFs in the plethora of environmental and biomedical fields, this article takes the lead by providing a detailed depiction of the synthesis and structural variation of the frameworks, potential application of pristine, surface functionalized and composite MOFs for sensing, monitoring and removal of pesticides from water using combination of Grand Canonical Monte Carlo and Molecular Dynamics (GCMC & MD) simulation models. It also highlights the recent advances in the field, mechanistic insights of adsorption, followed by the directions for future research. [ABSTRACT FROM AUTHOR]

The application of biocontrol agents in farm operations for pest control programs is gaining priority and preference globally. Effective delivery, infectivity of the biocontrol agents, and quality shelf-life products containing these bioagents are vital parameters responsible for the success of biopesticides under field conditions. In the present study, moisture-retaining bio-insecticidal dustable powder formulation (SaP) of Steinernema abbasi (Sa) infective juveniles (IJs) was developed and assessed for its shelf life, physicochemical profile, and bio-efficacy against subterranean termite under field conditions. Formulation exhibited free-flowing character, with pH of 6.50–7.50, and apparent density in the range 0.50–0.70 g cm−3. The bioefficacy study for two rabi seasons (2020–2021, and 2021–2022) in wheat and chickpea grown in an experimental farm heavily infested with subterranean termites (Odontotermes obesus) revealed a significant reduction in plant damage due to pest attack in formulation-treated plots, monitored in terms of relative number of infested tillers in wheat and infested plants in chickpea fields. The reduced damage to the crop caused by termite was reflected in the relative differences in the growth and yield attributes as well. The study establishes the potential of the developed product as a biopesticide suitable for organic farming and integrated pest management operations. [ABSTRACT FROM AUTHOR]

Environmental crises, declining factor productivity, and shrinking natural resource is a threat to global agricultural sustainability. The task is much more daunting in the Indo-Gangetic northern plains of India, where depletion of the underground water table and erratic rains due to the changing climate pose a major challenge to agriculture. To address these challenges a field investigation was carried out during 2016–2018 to test the efficacy of biopolymeric superabsorbent hydrogels namely Pusa Hydrogel (P-hydrogel: a semi-synthetic cellulose derivative-based product) and kaolin derivative of Pusa Hydrogel (K-hydrogel: semi-synthetic cellulose derivative) to assess their effect on crop and water productivity, soil moisture, root dynamics, and economics of soybean (Glycine max L.)–wheat (Triticum aestivum L.) system under three irrigation regimes namely full irrigation, limited irrigation and rainfed. The results revealed that the full irrigation along with P-hydrogel led to enhanced grain yield, biomass yield, and water productivity (WP) of soybean (1.61–10.5%, 2.2–9.5%, and 2.15–21.8%, respectively) and wheat (11.1–18.3%, 12–54% and 11.1–13.1%, respectively) over control plots. Likewise, under water stressed plots of rainfed conditions with P-hydrogel exhibited 52.7 and 20.6% higher system yields (in terms of wheat equivalent yield) over control and other combinations during the respective study years. Whereas the magnitude of increase in system yield under limited irrigation with P-hydrogel was ~ 15.1% and under full irrigation with P-hydrogel was 8.0–19.4%. Plots treated with P-hydrogel retained 3.0–5.0% higher soil moisture compared to no-hydrogel plots, while K-hydrogel treated plots held the lower moisture (4.0–6.0%) than the control. In terms of profitability, full irrigation along with P-hydrogel plots registered 12.97% higher economic returns over control. The results suggested that P-hydrogel (2.5 kg ha−1) reduces runoff water loss in full irrigation applied plots and retained more water, where loss of water is more thus reduces number of irrigations. Hence P-hydrogel with irrigation water is a viable option for sustainable production of soybean-wheat systems in the Indo-Gangetic plains of India and other similar eco-regions of the world. [ABSTRACT FROM AUTHOR]

• A method for quantifying AD, AA, and MBA in soil using LC-MS/MS. • The modified QuEChERS with addition of water enhances extraction recovery. • Method validated for specificity, linearity, sensitivity, accuracy, and precision. • The method LOQ for AD, AA, MBA in soil: 0.05, 1, 0.01 µg g–1. Acrylamide and N, N-methylene bis acrylamide are most commonly used monomer and crosslinker compounds employed in synthesis of super absorbent hydrogels. When applied as soil conditioners, there are apprehensions that these hydrogels degrade over time and thus may release the toxic monomers in the soil. A method was thus developed using Liquid Chromatography tandem mass spectrometry (LC-MS/MS) for the trace level quantification of acrylamide (AD), acrylic acid (AA) and N,N-methylene-bis-acrylamide (MBA) in sandy loam soil amended by two test hydrogels the Pusa Hydrogel and SPG 1118 hydrogel prepared using AD and MBA. The MRM (multiple reaction monitoring) transitions were optimized for both the compounds. Soil samples were extracted using dispersive solid-phase extraction (dSPE) with a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) technique, employing acetonitrile. All analytes were quantified at trace levels within a five-minute run using UHPLC equipped with a C-18 column. Single laboratory validation of the developed method in soil matrix was conducted based on specificity, linearity, sensitivity, accuracy, precision, matrix effect and measurement of uncertainty. LC-MS/MS exhibited a linear response in the concentration range of 0.001 to 1 µg mL−1, with correlation coefficient >+0.99. Acceptable recovery (within 70–120 %) with repeatability (%RSD ≤20 %) was obtained at 0.01 to 1 µg g–1 fortification levels. LOQ (Limit of quantification) of the method for AD, AA and MBA in soil matrix were 0.05, 1 and 0.01 µg g–1, respectively. Both intra-laboratory repeatability and intermediate precision at LOQ suggested well acceptable precise (HorRat≈ 0.3) method for quantification. Matrix enhancement effect was observed in the order: AA>AD>MBA. The Expanded Uncertainty (EU) in soil matrix at LOQ was 21.64 %, 28 % and 19 % for AD, AA and MBA respectively. Groundnut and wheat grown with application of the hydrogels showed no detectable residues of monomers in soil samples (total n = 60) near the root zone at the time of crop harvesting. [ABSTRACT FROM AUTHOR]

The inlet of wastewater treatment plants (WWTPs) contains pathogenic microorganisms which during aeration and by mechanical mixing through wind typically aerosolized microbes into ambient air. Bioaerosol emission and its characterization (bacterial and fungal) was investigated considering low-flow and high-flow inlet of wastewater treatment plant. Generation of bioaerosols was found influenced by prevailing seasons while both during summer and winter, fungal concentration (winter: 1406 ± 517; summer: 1743 ± 271 CFU/m3) was higher compared to bacterial concentration (winter: 1077 ± 460; summer: 1415 ± 588 CFU/m3). Bioaerosols produced from WWTPs were predominately in the size range of 2.1–4.7 μm while fraction of fungal bioaerosols were also in ultra-fine range (0.65 μm). Bioaerosols reaching to the air from WWTPs varied seasonally and was calculated by aerosolization ratio. During summer, aerosolization of the bioaerosols was nearly 6 times higher than winter. To constitute potential health effects from the exposure to these bioaerosols, biological characterization, antibiotics resistance and the health survey of the nearby area were also performed. The biological characterization of the bioaerosols samples were done through metagenomic approach using 16s and ITS metagenomic sequencing. Presence of 167 genus of bacteria and 41 genus of fungi has been found. Out of this, bacillus (73%), curtobacterium (21%), pseudomonas , Exiguo bacterium , Acinetobacter bacillaceae , Enterobacteriaceae and Prevotella were the dominant genus (top 10) of bacteria. In case of fungi, xylariales (49%), Hypocreales (19%), Coperinopsis (9%), Alternaria (8%), Fusarium (6%), Biopolaris , Epicoccum , Pleosporaceae , Cladosporium and Nectriaceae were dominant. Antibiotics like, Azithromycin and cefixime were tested on the most dominant bacillus showed resistance on higher concentration of cefixime and lower concentration of azithromycin. Population-based health survey in WWTP nearby areas (50–150 m periphery) found several types of diseases/symptoms including respiratory problem, skin rash/irritation, change in smell and taste, eye irritation within the resident population and workers. [Display omitted] • Wastewater treatment plant is a major contributor of bioaerosols in 2.1–4.7 μm size. • Microbe aerosolization has seasonal pattern with higher emission during summer (7.28 × 10−5). • Bacillus and curtobacterium are dominant bacterial genus in bioaerosols. • Xylariales , Hypocreales , Coperinopsis and Alternaria are common fungal genus. • Residents near to treatment plant has health issues linked to bioaerosol exposure. [ABSTRACT FROM AUTHOR]

The water issue has emerged as a significant barrier to agricultural productivity, particularly in dry and semiarid agro-ecologies, particularly during the winter season. Superabsorbent hydrogels have been identified as effective tools for improving crop and water productivity in arid locations by enhancing moisture retention. The application of hydrogel to soil is commonly done as a basal application, and its effectiveness is heavily influenced by the moisture level present in the soil. Therefore, a two-year field study was carried out to study the effects of various hydrogels and their application techniques and to assess the efficacy of recently developed cross–linked hydrogels (SPG 1118 and Pusa hydrogel) on soil water distribution (both spatial and temporal), water productivity and profitability of red cabbage. The experiment consisted of two irrigation regimes [full irrigation (100% ET c) and limited irrigation (75% ET c)] assisted in main plots, with two type of hydrogels (Pusa Hydrogel and SPG 1118) and two methods of application [root dipping and soil application of hydrogels and Control with no application of hydrogel] assisted in sub plots. The field experiment was conducted using spilt plot design with three replications. The analysis of soil water distribution patterns reveals that the utilization of hydrogels has resulted in a notable increase of 3–6% in soil water content (SWC) under full irrigation conditions, as compared to plots subjected to limited water conditions. In comparison to plots without hydrogel application, the plots treated with SPG 1118 and Pusa hydrogel exhibited enhanced soil water content of 5–6% and 2–4%, respectively. Additionally, the application of hydrogels in the root dipping showed increased water availability in the crop's root zone compared to soil application in throughout the crop season. Thus, hydrogels with reduced irrigation application resulted in significantly higher crop water productivity (14%) and irrigation water productivity (8 – 14%) compared to full irrigation levels. Likewise, root dipping of SPG 1118 led in considerable improvement in CWP (12–14%) and IWP (11–12%) over no hydrogel applied plots. In relation to profitability, the adoption of full irrigation in conjunction with SPG 1118 hydrogel resulted in an 8% increase in the benefit cost ratio compared to the control plots. Hence, the use of the unique SPG 1118 hydrogel through direct application to the roots, whether under conditions of full or limited irrigation, presents an inventive approach to address the growing issues of water shortages and sustainability in countries experiencing water stress. • Two irrigation regimes with two type of hydrogels and two methods of application were used • Soil moisture dynamics was studied in horizontal as well as vertical direction. • Crop and irrigation water productivity and crop economics was assessed. • Soil water distribution patterns revealed that hydrogels have resulted increased moisture content. • Root dipping of SPG 1118 hydrogel improved CWP (12–14%) and IWP (11–12%). [ABSTRACT FROM AUTHOR]

The short term effect of multiple air pollutants e.g. aerosols (black carbon, BC; PM 2.5 and PM 10) and trace gases (NO 2 , SO 2, and O 3) on all-cause mortality was systematically investigated in a typical urban pollution hotspot over central Indo-Gangetic Plain (IGP). To our knowledge, this would be the first report of mortality estimates for exposure to BC aerosols and multiple trace gases over South Asia. Daily all-cause mortality and ambient air quality were analyzed from 2009 to 2016 following a semiparametric quasi-Poisson regression model adjusting mean temperature (Tmean), relative humidity (RH), and long term time trend (Time) as potential confounders. Single pollutant model clearly established the significant impact of BC aerosols (against 10-unit increase in pollutant; 4.95%, 95% CI: 2.16–7.74), NO 2 (2.38%, 95% CI: 0.88–3.87%) and PM 2.5 exposure (1.06%, 95% CI: 0.45–1.66%) on mortality. The inclusion of co-pollutants in the multi-pollutant model increased the individual mortality risks for BC aerosols (7.3%). Mortality estimates were further stratified considering different effect modifiers viz. sex, age, place of death, and season. Almost in all the cases statistically insignificant differences in effect modification were noted for all the pollutants except PM 10. We also explored a distributed lag nonlinear model to estimate the lag effect and all the pollutants showed significant lag up to 3 days while BC showed lag effect up to 5 days. The exposure-response curves for individual air pollutants were mostly linear, while a considerable increase in mortality was noted for an exposure >15 μg m−3 for BC aerosols and >60 μg m−3 for PM 2.5. The effect estimates of air pollutants during haze and no-haze days were also defined. During haze days, mortality rose to 6.11% and 3.06% for each 10-unit increase in BC and NO 2 exposure, respectively. Significant effect of BC aerosol exposure on human mortality was established which reaffirms its inclusion as a potential health regulator for epidemiological studies. Image 1 • Mortality estimate of black carbon aerosols and multiple trace gases are reported. • Mortality estimate was particularly high for BC followed by NO 2 levels. • All the pollutants showed significant lag effect between lag 0–1 and lag 0–6 days. • Synergistic effect was noted when BC, Res.PM 2.5 and NO 2 were combined. • Mortality estimates of BC aerosols, PM 2.5 and NO 2 were higher during hazy days. [ABSTRACT FROM AUTHOR]

• Comprehensive multi-city study across the largest cities in India. • Strong evidence of heatwaves impact on daily mortality. • Longer and more intense heatwaves are linked to an increased mortality risk. • Higher heatwave-related deaths with shorter and less extreme heatwaves. • Policymakers should consider both heatwave definitions and their associated burden. Heatwaves are expected to increase with climate change, posing a significant threat to population health. In India, with the world's largest population, heatwaves occur annually but have not been comprehensively studied. Accordingly, we evaluated the association between heatwaves and all-cause mortality and quantifying the attributable mortality fraction in India. We obtained all-cause mortality counts for ten cities in India (2008–2019) and estimated daily mean temperatures from satellite data. Our main extreme heatwave was defined as two-consecutive days with an intensity above the 97th annual percentile. We estimated city-specific heatwave associations through generalised additive Poisson regression models, and meta -analysed the associations. We reported effects as the percentage change in daily mortality, with 95% confidence intervals (CI), comparing heatwave vs non-heatwave days. We further evaluated heatwaves using different percentiles (95th, 97th, 99th) for one, two, three and five-consecutive days. We also evaluated the influence of heatwave duration, intensity and timing in the summer season on heatwave mortality, and estimated the number of heatwave-related deaths. Among ∼ 3.6 million deaths, we observed that temperatures above 97th percentile for 2-consecutive days was associated with a 14.7 % (95 %CI, 10.3; 19.3) increase in daily mortality. Alternative heatwave definitions with higher percentiles and longer duration resulted in stronger relative risks. Furthermore, we observed stronger associations between heatwaves and mortality with higher heatwave intensity. We estimated that around 1116 deaths annually (95 %CI, 861; 1361) were attributed to heatwaves. Shorter and less intense definitions of heatwaves resulted in a higher estimated burden of heatwave-related deaths. We found strong evidence of heatwave impacts on daily mortality. Longer and more intense heatwaves were linked to an increased mortality risk, however, resulted in a lower burden of heatwave-related deaths. Both definitions and the burden associated with each heatwave definition should be incorporated into planning and decision-making processes for policymakers. [ABSTRACT FROM AUTHOR]

Observations on aerosols with specific emphasis to black carbon (BC) are reported for an urban site over middle Indo-Gangetic Plain (IGP), South Asia. Emphases are made to evaluate variation in BC concentrations during typical monsoon season (June-September, JJAS) from 2009 to 2011, and to recognize its impact on aerosol radiative forcing (ARF) and atmospheric heating. Almost entire Indian sub-continent experienced a drought year in 2009 before achieving a normal monsoon in 2010 and 2011. The ground monitoring station in Varanasi over middle-IGP experienced minimum monsoonal rain during 2009 drought year (total monsoon rain: 437.3 mm), which gradually increased during 2010 (deficit monsoon, 613.4 mm), before achieving a normal monsoon in year 2011 (1207.0 mm). The BC mass loading during drought year was relatively high (mean ± SD: 7.0 ± 3.3; range: 5.3–8.8 μg m −3 ) compared to 2010 (4.9 ± 2.1, 3.7–5.8 μg m −3 ) and 2011 (4.6 ± 2.1, 3.2–5.2 μg m −3 ). The increase in BC aerosols especially during drought year was associated to lower wind speed and reduced rate of wet removal, which potentially enhanced BC loading in comparison to years with normal monsoon. Columnar aerosol loading in terms of aerosol optical depth (AOD) was retrieved from space-borne MODerate resolution Imaging Spectroradiometer (MODIS) sensor on-board Terra satellite. It has revealed high AOD over Varanasi during drought (2009: 1.03 ± 0.15) and deficit monsoon (2010: 1.07 ± 0.53) before being reduced during 2011 (0.89 ± 0.20). Conclusively, a radiative transfer model was run to estimate the ARF for composite aerosols for both surface (SUF), atmosphere (ATM) and top of the atmosphere (TOA). The 2009 drought year was found to have reasonably higher ATM and SUF forcing (ATM: 105; SUF: − 122 W m −2 ) in comparison to deficit (ATM: 61; SUF: − 88 W m −2 ) and normal (ATM: 67; SUF: − 89 W m −2 ) monsoon scenarios. The lower atmosphere heating rates during 2009 monsoon was also recorded to be as high as 2.9 K day −1 in comparison to 2010 (1.7 K day −1 ) and 2011 (1.9 K day −1 ). Such findings provide meaningful outcomes in terms of climatic effects of BC aerosols and their associated inference on Indian summer monsoon. Capsule BC induced aerosol radiative forcing during 2009 drought year was higher in comparison to deficit (2010) and normal (2011) monsoon scenarios over middle IGP. [ABSTRACT FROM AUTHOR]

This work examines the impact of different environmental attributes on the uncertainty in satellite-based Aerosol Optical Depth (AOD) retrieval against the benchmark Aerosol Robotic Network (AERONET) AOD measurements at 21 sites across North Africa, California and Germany, in the years 2007–2017. As a first step, we studied the effects of spatial averaging the Multi-Angle Implementation of Atmospheric Correction (MAIAC) AOD retrievals, and of temporal averaging the AERONET AOD around the satellite (Aqua) overpass, on the agreement between the two products. AERONET AOD averaging over a time-window of ±15 min around the satellite overpass and the 1 × 1 km2 spatial grid of MAIAC were found to provide the best AOD retrieval performance. Next, MAIAC AOD were stratified according to different co-measured environmental attributes (aerosol loading, dominant particle size, vegetation cover, and prevailing particle type) and analyzed against the AERONET AOD. The envelope of the expected retrieval error varied considerably among different environmental attributes categories, with more accurate AOD retrievals obtained over highly vegetated areas (i.e. less surface reflectance) than over arid areas. Moreover, the retrieval accuracy was found to be sensitive to the aerosol loading and particle size, with a large bias between the MAIAC and AERONET AOD during high aerosol loading of coarse particles. In addition, the retrieval accuracy of MAIAC AOD was found to depend on the aerosol type due to the aerosol model assumptions regarding their optical properties. [Display omitted] • The MAIAC AOD retrieval uncertainty varies with the scene attributes. • Scene attributes include the surface reflectance and aerosol characteristics. • The latter accounts for the aerosol loading and thermophysical properties. • Large AOD retrieval bias & low expected error were noted during certain conditions. • Improved retrieval performance requires enhanced regional aerosol models. [ABSTRACT FROM AUTHOR]

The present study summarizes two decades (2000–2019) of climatology and trends in aerosol loading and optical properties using a high spatial resolution data obtained from NASA's MODIS MAIAC and MISR aerosol products supplemented by moderate resolution aerosol data from OMI sensor over South Asia (SA). MISR AOD showed good agreement against AERONET AOD with 68.68% of the retrievals falling within the expected error and high Pearson's correlation coefficient (R = 0.83). The 20 years geometric mean of MAIAC and MISR AOD revealed higher loading of aerosols over the Indo-Gangetic Plain (IGP) and Eastern coast of India by 30% to 44% compared to the mean AOD over the entire SA. The highest mean AOD under cloud-free conditions was noted during monsoon season, followed by pre-monsoon, post-monsoon, and winter. The high contribution of coarse-mode AOD (cAOD) mainly from natural aerosol emission and small-mode AOD (sAOD) from local anthropogenic emissions are the main driver to high AOD in monsoon and pre-monsoon seasons. Besides, the presence of high humidity during the monsoon season favors the hygroscopic growth of the particles and leads to higher AOD values over SA. The high spatial resolutions of MODIS/MAIAC and MISR aerosol products enabled the identification of previously unobserved aerosol hotspots over Bihar, West Bengal, and the eastern Indian coastal state of Odisha, which is mainly dominated by small aerosol particles. The contributions of smaller aerosol particles to the total aerosol loading were found to be higher during post-monsoon and winter over most states in India, Nepal, and Bangladesh. In contrast, the contribution of coarser particles was higher over Pakistan during pre-monsoon and monsoon seasons. Smaller particles were predominantly retrieved over the Indian states dominated by mining industries, including Jharkhand and Odisha. A typical dominance of absorbing carbonaceous aerosols was also noted over the northwestern region of IGP during post-monsoon, which otherwise was mainly affected by mixed dust aerosols and carbonaceous aerosols in pre-monsoon and monsoon seasons. A statistically significant positive temporal trend in AOD was observed for the whole study period, over most of the SA region, which was influenced by the increase in small particles over India and Bangladesh. Urban/industrial weakly absorbing aerosols were found to be the main contributor to a similarly positive trend over Central India and East coast Indian states. Overall, recent advancements in high spatial resolution satellite-based aerosol optical properties showed good potential to identify the aerosol hotspots and constrain aerosol types across a highly polluted SA region. • The latest MISR V23 AOD product showed promising agreement with ground observations. • Significant positive trends in MISR and MAIAC AOD are identified over South Asia. • Climatological trends recognize the Eastern Indian coast as a new aerosol hotspot. • Small aerosol particles contribute to >54% of the total AOD in all seasons. • Anthropogenic sources are the major contributor to high aerosol loading over SA. [ABSTRACT FROM AUTHOR]

Multi–locational supervised field trials were conducted in different agro–climatic regions in India to study dissipation of trifloxystrobin and tebuconazole in tomato after spraying a combination formulation (trifloxystrobin 25% + tebuconazole 50%, 75WG) at recommended doses: (i) single (trifloxystrobin 87.5 g a.i. ha−1 + tebuconazole 175 g a.i. ha−1) and (ii) double (trifloxystrobin 175 g a.i. ha−1 + tebuconazole 350 g a.i. ha−1). Fruit samples were extracted with ethyl acetate using a modified QuEChERS method. The residues (parent fungicides + metabolite) were analyzed and confirmed by GC–ECD and GC–MS, respectively. The half–life (t 1/2) of trifloxystrobin and tebuconazole in tomato varied from 1.08 to 1.72 and 1.13 –to 1.64 days at single; and 1.27 to 2.13 and 1.24 to 1.96 days at double dose, respectively. Since maximum residue limit (MRL) at pre–harvest interval (PHI) of 5 days is impractical, as tomato is usually harvested and consumed almost everyday after the last spray, the risk assessment was performed at minimum PHI of 1 day. Accordingly, on the basis of supervised field trial data and using OECD MRL calculator, MRL of 0.5 and 1.5 mg kg−1 at single dose were proposed for trifloxystrobin and tebuconazole in/on tomato, respectively. • Multi–location field trial of trifloxystrobin + tebuconazole in tomato was conducted. • Samples were extracted with EtOAc, analyzed by GC–ECD and confirmed with GC–MS. • Method performance was satisfactory with recovery of >83% at LOQ 0.05 mg kg−1. • Dissipation of fungicide residues followed first order kinetics. • Half–life, risk assessment, and MRLs were derived for safe use of both fungicides. [ABSTRACT FROM AUTHOR]

Cross-country assessment of aerosol loading was made over several South Asian megacities using multiple high-resolution remote-sensing database to assess how aerosols vary within the city and its suburbs. Parameters sensitive to aerosol optical and microphysical properties were processed over city-core and its surrounding, separated by a buffer. Cities across the Indo-Gangetic Plain (IGP; AOD:0.52-0.72) along with Mumbai (0.47) and Bangalore (0.46) denote comparatively high aerosol loading against non-IGP cities. City-core specific AOD was invariably high compared to surrounding, however with varying gradient having robust geographical signature. Exceptions to this general trend were in Kathmandu (ΔAOD: 0.07) and Dhaka (ΔAOD: 0.01) while strong positive AOD gradient was noted in Bangalore (+0.11), Colombo (+0.08) and in Mumbai (+0.07). While all mainland cities exhibited robust intraannual variability, distinction between city-core and its surrounding AOD exhibited varying seasonality. City-specific geometric coefficient of variation indicated insignificant association with mean AOD as opposed to European and American cities. Both pixel-based and city-specific analysis revealed a strong increasing trend in AOD with highest magnitude in Varanasi and Bangalore. Aerosol sub-types based on aerosols' sensitivity to UV-absorption and particle size denotes higher relative abundance of carbonaceous smoke aerosols within city-core, without having significant distinction for mineral dusts and urban aerosols., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a threat to maize production systems, is a polyphagous pest of global significance. There is no registered bioinsecticide of botanical origin to provide green remedy against this pest of concern. The present study reports for the first time the potency of the polar and non-polar bioinsecticidal leads sourced from Lippia alba (Mill.) N.E. Br. leaves. Shade-dried leaves of L . alba were extracted and evaluated; based on preliminary bioassay, the ethyl acetate leaf extract of L . alba ( LEAE ) was found to be the most potent against FAW in the in vitro and in vivo studies. Ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometric (UPLC-QToF-MS) analysis of LEAE revealed the rich chemical profile of 28 compounds, dominated by flavones, namely, naringenin, trihydroxy-dimethoxy flavone, and dihydroxy-trimethoxy flavone. Among others, glycosides, such as clerodendrin, calceolarioside E, forsythoside B, geniposide, and martynoside, and glucuronides, such as luteolin-7-diglucuronide, tricin-7-O-glucuronide, and luteolin-7-O-glucuronide, were also identified. LEAE exhibited exceptionally high in vitro [LC 50 = 6,900 parts per million (ppm)] and in vivo (computed as damage score on a scale of 1-9) insecticidal activity against S . frugiperda , with no phytotoxicity at a dose as high as 20 times of LC 50 . LEAE also exhibited significant antifeedant, ovicidal, and growth regulatory activity at the 70-16,000 ppm (w/v) concentration range. In silico assessment revealed strong binding of martynoside, calceolarioside E, and forsythoside B with acetylcholinesterase-, sodium-, and chloride-dependent γ-aminobutyric acid (GABA) receptor and ryanodine receptor, respectively, facilitated by hydrogen bonds (conventional and C-H bonds) stabilized by hydrophobic pi-sigma, pi-pi stacked, pi-alkyl, and alkyl interactions. The present study established L. alba as a potential bioresource and secondary metabolite enriched LEAE as bioinsecticide for further product development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Biswas, Kundu, Suby, Kushwah, Patanjali, Shasany, Verma, Saha, Mandal, Banerjee, Kumar and Singh.)

The presence of undesired agrochemicals residues in soil and water poses risks to both human health and the environment. The behavior of pesticides in soil depends both on the physico-chemical properties of pesticides and soil type. This study examined the adsorption-desorption and leaching behavior of the maize herbicide tembotrione in soils of the upper (UGPZ), trans (TGPZ) and middle Gangetic plain zones of India. Soil samples were extracted using acetone followed by partitioning with dichloromethane, whereas liquid-liquid extraction using dichloromethane was used for aqueous samples. Residues of tembotrione and its metabolite TCMBA, {2-chloro-4-(methylsulfonyl)-3-[(2,2,2-trifluoroethoxy) methyl] benzoic acid}, were quantified using liquid chromatography-tandem mass spectrometry. The data revealed that tembotrione adsorption decreased with increasing pH and dissolved organic matter but increased with salinity. The maximum adsorption occurred at pH 4, 0.01 m sodium citrate and 4 g/L NaCl, with corresponding Freundlich constants of 1.83, 2.28 and 3.32, respectively. The hysteresis index <1 indicated faster adsorption than desorption. Leaching studies under different flow conditions revealed least mobility in UGPZ soil and high mobility in TGPZ soil, consistent with groundwater ubiquity scores of 4.27 and 4.81, respectively. Soil amendments decreased tembotrione mobility in the order: unamended > wheat straw ash > wheat straw > farm yard manure > compost. The transformation of tembotrione to TCMBA and its mobility in soil columns were also assessed., (© 2024 John Wiley & Sons Ltd.)

Background: The evidence for acute effects of air pollution on mortality in India is scarce, despite the extreme concentrations of air pollution observed. This is the first multi-city study in India that examines the association between short-term exposure to PM 2·5 and daily mortality using causal methods that highlight the importance of locally generated air pollution., Methods: We applied a time-series analysis to ten cities in India between 2008 and 2019. We assessed city-wide daily PM 2·5 concentrations using a novel hybrid nationwide spatiotemporal model and estimated city-specific effects of PM 2·5 using a generalised additive Poisson regression model. City-specific results were then meta-analysed. We applied an instrumental variable causal approach (including planetary boundary layer height, wind speed, and atmospheric pressure) to evaluate the causal effect of locally generated air pollution on mortality. We obtained an integrated exposure-response curve through a multivariate meta-regression of the city-specific exposure-response curve and calculated the fraction of deaths attributable to air pollution concentrations exceeding the current WHO 24 h ambient PM 2·5 guideline of 15 μg/m 3 . To explore the shape of the exposure-response curve at lower exposures, we further limited the analyses to days with concentrations lower than the current Indian standard (60 μg/m 3 )., Findings: We observed that a 10 μg/m 3 increase in 2-day moving average of PM 2·5 was associated with 1·4% (95% CI 0·7-2·2) higher daily mortality. In our causal instrumental variable analyses representing the effect of locally generated air pollution, we observed a stronger association with daily mortality (3·6% [2·1-5·0]) than our overall estimate. Our integrated exposure-response curve suggested steeper slopes at lower levels of exposure and an attenuation of the slope at high exposure levels. We observed two times higher risk of death per 10 μg/m 3 increase when restricting our analyses to observations below the Indian air quality standard (2·7% [1·7-3·6]). Using the integrated exposure-response curve, we observed that 7·2% (4·2%-10·1%) of all daily deaths were attributed to PM 2·5 concentrations higher than the WHO guidelines., Interpretation: Short-term PM 2·5 exposure was associated with a high risk of death in India, even at concentrations well below the current Indian PM 2·5 standard. These associations were stronger for locally generated air pollutants quantified through causal modelling methods than conventional time-series analysis, further supporting a plausible causal link., Funding: Swedish Research Council for Sustainable Development., Competing Interests: Declaration of interests PP reports working as a consultant for World Bank for climate change and health outcomes. GAW reports receiving consulting income from the Health Efects Institute and Google. PL has received air travel and hotel accommodation paid by Fondazione Menarini to attend and hold a presentation at the Respirami meeting in Milan. He is the Scientific Secretary of the Swedish Society of Cardiology and co-chair of the European Chapter of International Society of Environmental Epidemiology (both unpaid). He was a paid member of the ethical committee board for the Swedish Ethical Authority 2022–23. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Biopurification system (BPS) or biobeds are low-cost system for decontamination of on-farm generated pesticide waste. A biobed contains a mixture of soil, lignocellulosic biomass and organic matter source (compost/peat) and works on the principal of retention of pesticide in high organic matter matrix and its subsequent degradation by microbes. Bioaugmentation, a green technology, is defined as the improvement of the degradative capacity of biobeds by augmenting specific microorganisms. During last 20 years, several studies have evaluated pesticide degradation in biobeds augmented with bacterial and fungal species and prominent microorganism include genus Pseudomonas, Sphingomonas, Arthrobacter, Phanerochaete, Stereum, Delftia, Trametes, Streptomyces etc. Degradation of pesticides belonging to major classes have been studied in the bioaugmented biobeds. Studies suggested that some pesticides were degraded faster in the bioaugmented biobeds subject to survival and proliferation of degrading microbe. However, no effect of bioaugmentation was observed on degradation of some pesticides and no clear reason for the same was evident. Bioaugmentation with pesticide degrading microorganisms/consortium in combination with rhizosphere-assisted biodegradation could be an optimal strategy for accelerating the degradation of pesticides in biobeds.

The present investigation aims to study adsorption-desorption behavior of glyphosate and tricyclazole in rice straw-compost biomixtures. To enhance pesticide adsorption and performance of the bio-purification system, rice straw-compost (BM) biomixture was mixed with wheat straw biochar (WBC, 1% and 5%), and adsorption of both pesticides in control (BM) and WBCBM(1%) and WBCBM(5%) biomixtures was compared. The kinetics study suggested that the pseudo-second-order model best explained the time-dependent adsorption of both pesticides and intraparticle adsorption was not the rate-determining step. Tricyclazole was more sorbed than glyphosate in all biomixtures which can be attributed to its lower water solubility. The WBC increased the sorption of both pesticides, but the effect varied with the nature of pesticides and biochar content. The adsorption coefficient values in BM, WBCBM(1%), and WBCBM(5%) biomixtures were 26.74, 38.16, and 51.97 (glyphosate) and 38.07, 59.94, and 84.54 (tricyclazole), respectively. The adsorption data was subjected to the Freundlich, the Langmuir, and the Temkin isotherms, and among them, the Freundlich isotherm best explained pesticide adsorption behavior. Desorption results suggested that the adsorption of glyphosate was more irreversible than tricyclazole and depended upon initial pesticide concentration. This study suggested that biochar mixed rice straw-compost biomixtures can be exploited in bio-purification systems for glyphosate and tricyclazole.

A robust method was developed using LC-ESI-MS/MS-based identification and quantification of 103 fortified pesticides in a mango fruit drink. Variations in QuEChERS extraction (without buffer, citrate, and/or acetate buffered) coupled with dispersive clean-up combinations were evaluated. Results showed 5 mL dilution and citrate buffered QuEChERS extraction with anhydrous (anhy) MgSO 4 clean-up gave acceptable recovery for 100 pesticides @ 1 μg mL -1 fortification. The method was validated as per SANTE guidelines (SANTE/11813/2021). 95, 91, and 77 pesticides were satisfactorily recovered at 0.1, 0.05, and 0.01 μg mL -1 fortification with HorRat values ranging from 0.2-0.8 for the majority. The method showed matrix enhancement for 77 pesticides with a global uncertainty of 4.72%-23.89%. The reliability of the method was confirmed by real sample analysis of different brands of mango drinks available in the market. The greenness assessment by GAPI (Green Analytical Procedure Index) indicated the method was much greener than other contemporary methods., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Tippannanavar, Banerjee, Shekhar, Sahu, Singh, Narayanan, Rudra, Chakrabarti, Gupta and Singh.)

Abundance of fine particulate-bound 16 priority polycyclic aromatic hydrocarbons (PAHs) was investigated to ascertain its sources and potential carcinogenic health risks in Varanasi, India. The city represents a typical urban settlement of South Asia having particulate exposure manyfold higher than standard with reports of pollution induced mortalities and morbidities. Fine particulates (PM 2.5 ) were monitored from October 2019 to May 2020, with 32% of monitoring days accounting ≥100 μgm -3 of PM 2.5 concentration, frequently from November to January (99% of monitoring days). The concentration of 16 priority PAHs varied from 24.1 to 44.6 ngm -3 (mean: 33.1 ± 3.2 ngm -3 ) without much seasonal deviations. Both low (LMW, 56%) and high molecular weight (HMW, 44%) PAHs were abundant, with Fluoranthene (3.9 ± 0.4ngm -3 ) and Fluorene (3.5 ± 0.3ngm -3 ) emerged as most dominating PAHs. Concentration of Benzo(a)pyrene (B(a)P, 0.5 ± 0.1ngm -3 ) was lower than the national standard as it contributed 13% of total PAHs mass. Diagnostic ratios of PAH isomers indicate predominance of pyrogenic sources including emissions from biomass burning, and both from diesel and petrol-driven vehicles. Source apportionment using receptor model revealed similar observation of major PAHs contribution from biomass burning and fuel combustion (54% of source contribution) followed by coal combustion for residential heating and cooking purposes (44%). Potential toxicity of B[a]P equivalence ranged from 0.003 to 1.365 with cumulative toxicity of 2.13ngm -3 . Among the PAH species, dibenzo[h]anthracene contributed maximum toxicity followed by B[a]P, together accounting 86% of PAH induced carcinogenicity. Incremental risk of developing cancer through lifetime exposure (ILCR) of PAHs was higher in children (3.3 × 10 -4 ) with 56% contribution from LMW PAHs, primarily through ingestion and dermal contact. Adults in contrast, were more exposed to inhale airborne PAHs with cumulative ILCR of 2.2 × 10 -4 . However, ILCR to PM 2.5 exposure is probably underestimated considering unaccounted metal abundance thus, require source-specific control measures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2023 Elsevier Ltd. All rights reserved.)

White rot fungi possess an enzymatic system that is non-specific to any pesticide and can be used for pesticide detoxification in biobeds. The present study evaluated potential of Phanerochaete chrysosporium to degrade co-applied atrazine and fipronil in ash or biochar biomixtures. Five biomixtures were prepared by partially replacing compost in rice straw-compost biomixture (BM) with 10% rice husk ash (RHA), 10% sugarcane bagasse ash (SBA), and 1 and 5% wheat straw biochar (WBC). Results suggested that after 30 days P. chrysosporium augmented biobeds resulted in 60.52-72.72% atrazine and 69.57-72.52% fipronil degradation. Hydroxyatrazine and fipronil sulfone were detected as the only metabolite of atrazine and fipronil, respectively, and were further degraded. Although, SBA significantly enhanced atrazine degradation, RHA or SBA had no significant effect on fipronil degradation. WBC (5%) slowed down degradation of both pesticides., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)