Contamination of soils with arsenic (As) represents a global environmental and health issue considering the entrance of toxic As in the human food chain. Although partially understood, addition of compost for the remediation of As-contaminated soils may result in distinct effects on plant growth and physiological attributes depending on compost-mediated potential mobility/sequestration of As in soils. This study explores the role of compost addition (C; 0, 1 and 2.5%) on morphological and gas exchange attributes and photosynthetic pigments (chlorophyll contents) of maize plants under As stress (0, 40, 80, 120 mg kg−1), as well as soil As immobilization/mobilization in a pot experiment, using two contrasting soils. Results revealed that, in Narwala (sandy loam) soil, the addition of compost decreased shoot As concentration of maize plants (p \u3c 0.05; 4.01–13.7 mg kg−1 dry weight (DW)), notably at C2.5 treatment, with significant improvement in shoot dry biomass, gas exchange attributes and chlorophyll (a and b) contents, i.e., 1.33–1.82, 1.20–2.65 and 1.34–1.66 times higher, respectively, over C0 at all As levels. Contrastingly, in Shahkot (clay loam) soil, C2.5 treatment increased shoot As concentration (p \u3c 0.05; 7.02–17.3 mg kg−1 DW), and as such reduced the shoot dry biomass, gas exchange attributes and chlorophyll contents, compared to the control – rather C1 treatment was more effective and exhibited positive effect than C2.5. Considerably, at C2.5 treatment, phosphate extractable (bioavailable) soil As concentration was also found to be greater in the (post-experiment) Shahkot soil than that of Narwala soil (0.40–3.82 vs. 0.19–1.51 mg kg−1, respectively). This study advanced our understanding to resolve the complex compost-As interactions in As-contaminated soils, which are imperative to understand for developing the effective and soil-specific remediation strategies

Monsoon plays a determinant role in defining the air quality of many Asian countries. Filter-based 24 h ambient PM₁₀ and PM_2.5 sampling was performed by using two paralleled medium volume air samplers during pre-and post-monsoon periods. A negligible change in PM_2.5 mass concentration from 45.77 to 44.46 µg/m³ compared to PM₁₀ from 74.34 to 142.49 µg/m³ was observed after the monsoon season. The air quality index (AQI) results showed that the air quality of the city retained from good to slightly polluted in both periods, where PM_2.5 remained as the main detrimental to air quality in 95% of the total days. The NOAA HYSPLIT model analysis and wind rose patterns showed air trajectories, especially in post-monsoon originated from relatively polluted areas transported higher PM₁₀. Meteorological attributes indicated a more conducive atmospheric condition for secondary pollution in the pre-monsoon. Evidence showed post-monsoon as a more polluted period, compared to the pre-monsoon and would pose an extra 1.07×10⁻³ lifetime risk to the local population. Similarly, a higher level of PM₁₀ in the post-monsoon caused 43% more premature mortality and 41% more deaths from all-cause mortality compare to the pre-monsoon period, respectively. Implications: Pakistan is an under-developing country where pollution monitoring studies are decidedly limited. Notably, studies, concise PM_2.5 and health assessment are deficient. The present study may contribute to evaluating the air quality in special events such as monsoon and can also provide scientific and technical support for subsequent air pollution research. Moreover, the results help to develop adequate prevention and pollution control strategies and offer policy suggestions for monsoon observing countries in general and in particular, in Islamabad, Pakistan. These findings provide essential arguments in favor of educating people and raising awareness about the detrimental health effects of air pollution. Improving the quality of life of people with cardiovascular and respiratory disorders requires an immediate and substantial reduction of air pollution.