Achieving global food security and ensuring sustainable agriculture, the dual objectives of the second Sustainable Development Goal (SDG 2), necessitate immediate and collaborative efforts from ...developing and developed nations. The adverse effects of ozone on crop yields have the potential to significantly undermine the United Nations' ambitious target of attaining food security and ending hunger by 2030. This review examines the causes of growing tropospheric ozone, especially in India and China which lead to a substantial reduction in crop yield and forest biomass. The findings show that a nexus of high population, rapid urbanization and regional pollution sources aggravates the problem in these countries. It elucidates that when plants are exposed to ozone, specific cellular pathways are triggered, resulting in changes in the expression of genes related to hormone production, antioxidant metabolism, respiration, and photosynthesis. Assessing the risks associated with ozone exposure involves using response functions that link exposure-based and flux-based measurements to variables like crop yield. Precisely quantifying the losses in yield and economic value in food crops due to current ozone levels is of utmost importance in comprehending the risks ozone poses to global food security. We conclude that policymakers should focus on implementing measures to decrease the emissions of ozone precursors, such as enhancing vehicle fuel efficiency standards and promoting the use of cleaner energy sources. Additionally, efforts should be directed toward mapping or developing crop varieties that can tolerate ozone, applying protective measures at critical stages of plant growth and establishing ozone-related vegetation protection standards.
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•Tropospheric ozone jeopardises food security.•Use of OTC and FACE systems to evaluate O3-crop response.•Exposure-based index AOT40 widely used in studies.•Use of emission control, chemical protectants, and bioengineering techniques to prevent yield losses.
The identification of highly toxic metals like Cd, Ni, Pb, Cr, Co or Cu in ambient particulate matter (PM) has garnered a lot of interest recently. Exposure to toxic metals, including carcinogenic ...ones, at levels above recommended limits, can significantly affect human health. Prolonged exposure to even trace amounts of toxic or essential metals can also have negative health impacts. In order to assess significant risks, it is crucial to govern the concentrations of bioavailable/bio-accessible metals that are available in PM. Estimating the total metal concentrations in PM is only an approximation of metal toxicity. This review provides an overview of various procedures for extracting soluble toxic metals from PM and the importance of chemical fractionation in risk assessment. It is observed that the environmental risk indices such as bioavailability index (BI), contamination factor (CF) and risk assessment code (RAC) are specifically influenced by the concentration of these metals in a particular fraction. Additionally, there is compelling evidence that health risks assessed using total metal concentrations may be overestimated, therefore, the metal toxicity assessment is more accurate and more sensitive to the concentration of the bioavailable/bio-accessible fraction than the total metal concentrations. Hence, chemical fractionation of toxic metals can serve as an effective tool for developing environmental protection laws and improving air quality monitoring programs for public health.
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The problem of air pollution poses a major challenge in the city of Taj, Agra because of rapid urbanization and tourism. Research on PM2.5/PM10 ratio contributes to a deeper understanding of the air ...pollution scenario and promoting sustainable development. This study was carried out at a suburban site in Agra (Jan 2021-Dec, 2022). We analyzed PM2.5/PM10 ratios, and their correlation with Air Quality Index and meteorological factors using various statistical approaches in the OpenAir package in RStudio. The mean concentrations of PM2.5 and PM10 were 46 and 67 μg/m3, respectively. The PM2.5/PM10 ratio was 0.65, indicating fine particulate dominance. Diurnal, intra-annual, and weekly cycles of PM2.5, PM10, and PM2.5/PM10 ratios were examined. PM2.5/PM10 ratio increased with increasing AQI. Correlation analysis revealed, a strong positive correlation (r = 0.94) between PM10 and PM2.5 while the PM2.5/PM10 ratios showed negative association with wind speed (WS), and temperature, and positive association with relative humidity (RH). Higher RH led to higher PM2.5/PM10 ratios indicating worsening of PM2.5 pollution during winter and post-monsoon. Bivariate polar plots exhibited the lowest PM2.5/PM10 ratios in summer at high WS (>10 m/s) from the west, and the highest PM2.5/PM10 ratios in winter and post-monsoon at low WS (<10 m/s).
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•PM2.5 and PM10 (r = 0.94) were highly correlated.•PM2.5/PM10 ratio was higher in winter and post-monsoon.•Higher relative humidity led to higher PM2.5/PM10 ratio.•PM2.5/PM10 ratio showed negative association with wind speed and temperature.
