Heavy metals are a group of metallic elements that have high densities and are often toxic at low concentrations. Common examples include lead, mercury, cadmium, and arsenic. These metals can be found in the environment due to natural processes and human activities, such as mining, industrial production, and waste disposal. Exposure to heavy metals can pose serious health risks to humans and wildlife. They can accumulate in the body over time, leading to various health issues, including neurological damage, kidney problems, and developmental disorders. Monitoring and regulating heavy metal levels in the environment is crucial for public health and safety.