Uncovering Soil Heavy Metal Pollution in Jiaozuo City

A city trying to figure out what's making its soil dirty. That's what happened in Jiaozuo, China. Scientists looked at 53 different types of land to find out where the heavy metals were coming from. They used a special tool called a Random Forest model, made better with a Genetic Algorithm, and something called a Geodetector. First, they mapped out 8 things people do, like factories and roads, 9 natural things, like vegetation, and 4 things about the soil itself. Then, they found three big reasons for the pollution. The first one was mostly from factories, with things like how close they were to other places playing a big role. Metals like chromium and copper were big in this group. The second group was a mix of natural stuff and roads. The amount of vegetation and how close roads were mattered here. The third group was all about farming. The more farmland there was, the more a metal called arsenic showed up. This one was the worst, with a high risk of hurting the environment. They also checked how these pollutants might affect people's health. Farming was the biggest cause of a type of cancer risk from arsenic in farmland. Overall, most people weren't at a high risk though. This new way of looking at things helps figure out what's causing the pollution better than older methods.