Ozone is a major air pollutant that is formed by the reaction of nitrogen oxides and volatile organic compounds in the presence of sunlight.

Sewage discharge is the primary source of water contamination in developing countries, as it releases untreated wastewater into water bodies, leading to the spread of waterborne diseases.

Landfilling is a common method for solid waste disposal, where waste is buried in a designated area.

Agriculture is the main cause of deforestation in tropical regions, as forests are cleared to make way for agricultural land.

Lead exposure can cause neurological damage, particularly in children, leading to developmental issues and cognitive impairment.

Cooking with biomass fuels, such as wood, charcoal, and dung, is a major source of indoor air pollution in developing countries, releasing harmful pollutants like particulate matter and carbon monoxide.

The activated sludge process is a common method for wastewater treatment, where microorganisms are used to break down organic matter in wastewater.

Mercury exposure can cause neurological damage, leading to symptoms such as tremors, memory loss, and impaired coordination.

Catalytic converters are devices that reduce air pollution from vehicles by converting harmful pollutants into less harmful substances.

Arsenic exposure can increase the risk of various types of cancer, including lung cancer, bladder cancer, and skin cancer.

Paper recycling is a common method for solid waste recycling, where paper waste is processed to produce new paper products.

Asbestos exposure can cause mesothelioma, a rare and aggressive form of cancer that affects the lining of the lungs, chest, or abdomen.

Biological treatment is a common method for reducing water pollution from industrial wastewater, where microorganisms are used to break down organic pollutants.

Benzene exposure can increase the risk of leukemia, a type of cancer that affects the blood and bone marrow.

Renewable energy sources, such as solar, wind, and hydro, can help reduce greenhouse gas emissions by replacing fossil fuels.