Public transport systems are critical to economic productivity, urban mobility, and environmental sustainability, but they also present complex safety, health, and operational risks. Accidents, infrastructure failures, overcrowding, and infectious disease transmission all pose potential threats to passenger safety and public trust. Meanwhile, climate change adds further stress, with extreme weather events disrupting services and damaging…

Contamination of water sources — whether from industrial discharges, agricultural runoff, mining, or natural events — poses significant risks to human health, ecosystems, and economic activity. Pollutants such as heavy metals, pathogens, nitrates, pesticides, and emerging contaminants like PFAS can persist in water systems, creating both acute and chronic health threats. Incidents of contamination often…