Road surfaces and vehicular traffic contribute to heavy metals (HM) contamination of soil and plants, which poses various health risks to humans by entering the food chain. It is imperative to evaluate the status of contamination with HM and associated health risks in soils and plants, especially food crops. In this regard, five crop species, i.e., strawberry (Fragaria ananassa), wheat (Triticum aestivum), tomato (Lycopersicon esculentum), sugar cane (Saccharum officinarum), and tobacco (Nicotiana tabacum), were evaluated at 0–10, 10–50, and 50–100 m distance from the highway near the urban area (Takht Bhai) of Mardan, Khyber Pakhtunkhwa, Pakistan. Lead (Pb) and cadmium (Cd) accumulation, phenolics, carotenoids, chlorophyll, and proline contents in plant parts were assessed. Pb and Cd in plants decreased with an increase in distance. Pb was above the critical limit in all plants except wheat, Cd exceeded the permissible level of the World Health Organization in all plants except wheat and tomato. Pb and Cd were higher in strawberries. Tomato and strawberry fruits, tobacco leaves, and sugarcane stems showed higher Pb contents at a 0–10 m distance. Phenolic contents in leaves were higher than in roots. The target hazard quotient (THQ) in edible parts of most crops has been greater than one, which presents a threat to human health upon consumption. To the best of our knowledge, this study presents the first holistic approach to assess metal contamination in the selected area, its accumulation in field-grown edible crops, and associated health risk.

Growth of crops in the semi-arid and arid regions of the world is significantly affected by salinity stress. The present study investigated maize, which is a globally cultivated crop and known for its salt sensitivity. Widespread cultivation and notable characteristics of maize make it an exemplary model for investigating stress response. We analyzed maize plants morphological and biochemical responses under salinity stress at different intervals. Current results showed that under 100 mM NaCl stress, germination rate of maize seeds decreases up to 40% compared to their respective control non-stressed seeds. Additionally, prolonged exposure to salinity stress negatively impacted various physiological and biochemical aspects of maize plants including shoot/root length, leaf width, and chlorophyll contents, especially in plants treated with NaCl for 21 days. Furthermore, our findings showed that the NaCl stress triggered various enzymatic and non-enzymatic activities, including catalase (CAT), polyphenol oxidase (PPO), total polyphenol (TPP), and flavonoid in maize plants. However, maize plants respond differently to NaCl stress regarding protein content in different durations. This research underscores the urgent need for innovative strategies to mitigate salinity stress and food security for local maize varieties in saline regions and provides valuable insights to tackle these challenges.