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Arsenic (As) is one of the most toxic metalloids for humans. Above permissible levels of As cause severe health implications. Contaminated drinking water and food items may be the leading sources of As exposure to people all around the world. The current study assessed the levels of As in drinking water, vegetables, irrigation water, agricultural soils, and the human population (adult women and men) of rural and peri-urban areas of Multan (Pakistan). For a comparison between peri-urban (exposed site) and rural areas (control site), we sampled irrigation water, vegetables and vegetable-grown soils, drinking water, and human blood. In all sample types, As concentration was significantly higher at exposed site than at control site. Alarmingly, As concentration in drinking groundwater (34 µg As L−1) of exposed site was 3.4-folds higher than the permissible limit (set by WHO). Among the studied vegetables, the cumulative daily dietary intake of As was recorded maximum by the consumption of okra (474 ng d–1 on exposed site) and minimum by long melon (1 ng d–1 on control site). However, As intake via drinking water was estimated to contribute ≥ 98% of total As intake at both sites. Hence, the health risks associated with drinking As-contaminated groundwater were recorded much higher than the health risks associated with the consumption of As-contaminated vegetables. Blood As levels in most of the subjects at exposed site exceeded the safe limit of 12 µg L−1. Conclusively, the findings of the current study indicated that drinking contaminated groundwater may be the major cause of As-associated health risks in the region. [ABSTRACT FROM AUTHOR]

Urea is an important source of inorganic N under wheat (Triticum aestivum L.) production system in Multan, Pakistan. However, the average N loss is high, ranging from 22 to 53% of applied N, which poses adverse environmental impacts. Reduced tillage and combined application of biochar and optimal N fertilizer could improve wheat productivity and reduce N losses. We evaluated the effects of two tillage (conventional and reduced tillage), two biochar (no biochar and poultry waste biochar), and three inorganic N rate (0, 60, and 120 kg ha−1) treatments on productivity and economic profitability of wheat production for two continuous growing seasons (2014–2015 and 2015–2016). Generally, reduced tillage increased wheat grain yield, protein content, and total N uptake by 0.2 Mg ha−1, 3.0 kg kg−1, and 37.0 kg ha−1, respectively, when compared with conventional tillage. Biochar application increased wheat grain yield, protein content, and total N uptake by 0.3 Mg ha−1, 6.8 kg kg−1, and 38.6 kg ha−1, respectively, compared with no‐biochar plots. Reduced tillage was economically profitable within the two cropping seasons, but biochar application was not, because of the high price of biochar (US$1.00 kg−1 biochar) and application rate (10 Mg biochar ha−1). Overall, wheat production under reduced tillage, no biochar, and the 60‐kg N ha−1 rate resulted in the greatest economic profit in this study. [ABSTRACT FROM AUTHOR]