The leading cause of water contamination in countries without water treatment plants?

The leading cause of water contamination in countries without water treatment plants is often the lack of proper sanitation and waste management systems. This results in the runoff of human and animal waste, agricultural chemicals, and industrial pollutants into water sources. Additionally, the absence of infrastructure to treat or filter water exacerbates the problem, leading to widespread health risks for communities relying on untreated water. Consequently, contaminated water can lead to serious diseases, impacting public health and economic stability.