Children are more vulnerable than adults to environmental risks because of a number of factors:
- Children are constantly growing. They breathe more air, consume more food, and drink more water than adults do, in proportion to their weight.
- Children's central nervous, immune, reproductive, and digestive systems are still developing. At certain early stages of development, exposure to environmental toxicants can lead to irreversible damage.
- Children behave differently from adults and have different patterns of exposure. Young children crawl on the ground where they can be exposed to dust and chemicals that accumulate on floors and soils.
- Children have little control over their environment. Unlike adults, they may be both unaware of risks and unable to make choices to protect their health.
Children's health problems resulting from exposure to biologically contaminated water, poor sanitation, indoor smoke, rampant disease vectors such as mosquitoes, inadequate food supply, and unsafe use of chemicals and waste disposal, rank among the highest environmental burden of disease worldwide. Significant progress in reducing the environmental burden of disease on a global scale can only be achieved through focusing on the key risk factors, through a holistic approach. Comprehensive comparative risk assessment suggests a cluster of eight environmental issues, many of which may concur in the places where children dwell, play and learn. These issues are:
- Hazardous child labour
- Lack of physical activity
- The built environment
- Disasters and conflicts
Children can also be affected by other environmental risks such as: