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Lead pollution is a toxic metal that can accumulate in human and animal tissues. It mainly comes from various paints, coatings, batteries, smelting industries, hardware products, machinery, electroplating processes, cosmetics, hair dyes, glazed tableware, cutlery, coal, puffed foods, water pipes, etc. It enters the body through contaminated skin, digestive tract, and respiratory tract in the Nandan mining area, where it binds to various organs; its main toxic effects are anemia, neurological disorders, and kidney damage. Vulnerable groups include children, the elderly, and those with weakened immune systems. The safe concentration of lead for aquatic organisms is 0.16 mg/L; when rice and wheat are irrigated with water containing 0.1–4.4 mg/L of lead, the lead content in the crops increases significantly. Cadmium pollution Is not an essential element for the human body. Cadmium is highly toxic and can accumulate in the human body, primarily in the kidneys, causing changes in the function of the urinary system ； The main sources of cadmium include wastewater discharged from electroplating, mining, smelting, fuel production, batteries, and the chemical industry ； Cadmium is present in high levels in used batteries, as well as in fruits and vegetables, especially mushrooms. It is also found in small amounts in dairy products and grains. Cadmium can replace calcium in bones, causing the bones to become severely weakened and even break, it can disrupt stomach function, interfere with the enzyme systems involving zinc in humans and organisms, and lead to increased blood pressure. Vulnerable groups include mining workers and those with weakened immune systems. When the cadmium concentration in water is 0.1 mg/L, it can slightly suppress the self-purification capacity of surface water. The safe concentration of cadmium for silver carp is 0.014 mg/L; irrigation with water containing 0.04 mg/L of cadmium leads to significant contamination of the soil and rice. Contamination occurs when the cadmium concentration in agricultural irrigation water is 0.007 mg/L. Mercury pollution Mercury and its compounds are substances that can accumulate in the human body. It mainly comes from instrument factories, salt electrolysis, precious metal smelting, cosmetics, lighting fixtures, dental materials, coal combustion, aquatic organisms, etc. Once metallic mercury in the blood enters brain tissue, it gradually accumulates there; when it reaches a certain level, it can cause damage to the brain tissue. Meanwhile, some of the mercury ions are transferred to the kidneys. Inorganic mercury ions that enter water bodies can be converted into more toxic organic mercury, which enters the human body through the food chain and causes systemic poisoning ； Vulnerable groups include women, especially pregnant women, and those who enjoy seafood ； Natural water contains very little mercury, generally not exceeding 0.1 μg/L. Arsenic pollution: Arsenic is an element that is not essential for the human body. The toxicity of elemental arsenic is very low, but all arsenic compounds are toxic; trivalent arsenic compounds are more toxic than other arsenic compounds. Arsenic enters the body through the respiratory tract, digestive tract, and skin contact. If the amount ingested exceeds the amount excreted, arsenic accumulates in organs such as the liver, kidneys, lungs, **, placenta, bones, and muscles. It binds to enzyme systems within cells, thereby inhibiting their biological functions and rendering them inactive. Accumulation in hair and nails can lead to chronic arsenic poisoning, with an incubation period that can last several years or even decades. Chronic poisoning is characterized by symptoms related to the digestive system, the nervous system, and skin lesions. Arsenic also has carcinogenic effects and can cause skin cancer. Under normal circumstances, trace amounts of arsenic are present in soil, water, air, plants, and the human body, and they do not pose a hazard to humans. It mainly comes from decolorizing agents in mining, metallurgy, the chemical and pharmaceutical industries, and the glass industry, as well as various insecticides, rodenticides, arsenic-based drugs, fertilizers, cemented carbides, leather products, and pesticides ； The groups at risk include farmers, housewives, and workers in special occupations. The arsenic content in surface water varies greatly depending on the source and geographical conditions; it ranges from 0.2 to 230 μg/L in freshwater, with an average of 0.5 μg/L, and 3.7 μg/L in seawater. Chromium pollution mainly comes from low-quality cosmetic ingredients, leather treatments, the chromium-plated parts of metal components, industrial pigments, as well as raw materials used in tanning, rubber, and ceramics ； If ingested or consumed, it can cause poisoning symptoms such as abdominal discomfort and diarrhea, as well as allergic dermatitis or eczema. If inhaled, it irritates and corrodes the respiratory tract, leading to pharyngitis, bronchitis, and other conditions. Residents living in areas with severe water pollution, as well as those who are exposed to it frequently or in excessive amounts, are prone to conditions such as rhinitis, tuberculosis, diarrhea, bronchitis, and dermatitis. The main source of heavy metal pollution is industrial pollution, followed by traffic pollution and household waste pollution. Industrial pollution is mostly released into the environment through waste residues, wastewater, and exhaust gases; it accumulates in humans, animals, and plants, thereby causing significant harm to the environment and human health. The control of industrial pollution can be achieved through various technical methods and management measures to reduce its levels, ultimately meeting the established standards for pollutant emissions ； Traffic pollution is mainly caused by vehicle exhaust emissions; **a range of control measures have been established, such as using ethanol-blended gasoline and installing exhaust purification systems in vehicles** ； Environmental pollution in daily life mainly refers to pollution caused by household waste, such as used batteries, broken lighting fixtures, unused cosmetics, and glazed dishes. As for heavy metal pollution, we can reduce it to some extent by controlling its sources.