Environmental health

Environmental health is the branch of public health that is concerned with all aspects of thenatural and built environment that may affect human health. Other terms that concern or refer to the discipline of environmental health include environmental public health and environmental health and protection.

Environmental health is defined by the World Health Organization as:

Those aspects of the human health and disease that are determined by factors in the environment. It also refers to the theory and practice of assessing and controlling factors in the environment that can potentially affect health.

Environmental health as used by the WHO Regional Office for Europe, includes both the direct pathological effects of chemicals, radiation and some biological agents, and the effects (often indirect) on health and wellbeing of the broad physical, psychological, socialand cultural environment, which includes housing, urban development, land use andtransport.^[1]

Services

Environmental health services are defined by the World Health Organization as:

those services which implement environmental health policies through monitoring and control activities. They also carry out that role by promoting the improvement of environmental parameters and by encouraging the use of environmentally friendly and healthy technologies and behaviours. They also have a leading role in developing and suggesting new policy areas.

Environmental health practitioners may be known as sanitarians, public health inspectors, environmental health specialists, environmental health officers or environmental health practitioners. In many European countries physicians and veterinarians are involved in environmental health. Many states in the United States require that individuals have professional licenses in order to practice environmental health.California state law defines the scope of practice of environmental health as follows:

"Scope of practice in environmental health" means the practice of environmental health by registered environmental health specialists in the public and private sector within the meaning of this article and includes, but is not limited to, organization, management, education, enforcement, consultation, and emergency response for the purpose of prevention of environmental health hazards and the promotion and protection of the public health and the environment in the following areas: food protection; housing; institutional environmental health; land use; community noise control; recreational swimming areas and waters; electromagnetic radiation control; solid, liquid, and hazardous materials management; underground storage tank control; on-site septic systems; vector control; drinking water quality; water sanitation; emergency preparedness; and milk and dairy sanitation.^[2]

The environmental health profession had its modern-day roots in the sanitary and public health movement of the United Kingdom. This was epitomized by Sir Edwin Chadwick, who was instrumental in the repeal of the poor laws and was the founding president of the Association of Public Sanitary Inspectors in 1884, which today is the Chartered Institute of Environmental Health.

Environmental medicine may be seen as the medical branch of the broader field of environmental health. Terminology is not fully established, and in many European countries they are used interchangeably.

Disciplines of Environmental Health

Three basic disciplines generally contribute to the field of environmental health: environmental epidemiology, toxicology, and exposure science. Each of these disciplines contributes different information to describe problems in environmental health, but there is some overlap among them.

• Environmental epidemiology studies the relationship between environmental exposures (including exposure to chemicals, radiation, microbiological agents, etc.) and human health. Observational studies, which simply observe exposures that people have already experienced, are common in environmental epidemiology because humans cannot ethically be exposed to agents that are known or suspected to cause disease. While the inability to use experimental study designs is a limitation of environmental epidemiology, this discipline directly observes effects on human health rather than estimating effects from animal studies.
• Toxicology studies how environmental exposures lead to specific health outcomes, generally in animals, as a means to understand possible health outcomes in humans. Toxicology has the advantage of being able to conduct randomized controlled trials and other experimental studies because they can use animal subjects. However there are many differences in animal and human biology, and there can be a lot of uncertainty when interpreting the results of animal studies for their implications for human health.
• Exposure science studies human exposure to environmental contaminants by both identifying and quantifying exposures. Exposure science can be used to support environmental epidemiology by better describing environmental exposures that may lead to a particular health outcome, identify common exposures whose health outcomes may be better understood through a toxicology study, or can be used in a risk assessment to determine whether current levels of exposure might exceed recommended levels. Exposure science has the advantage of being able to very accurately quantify exposures to specific chemicals, but it does not generate any information about health outcomes like environmental epidemiology or toxicology.

Information from these three disciplines can be combined to conduct a risk assessment for specific chemicals or mixtures of chemicals to determine whether an exposure poses significant risk to human health. This can in turn be used to develop and implement environmental health policy that, for example, regulates chemical emissions, or imposes standards for proper sanitation.

Concerns

Environmental health addresses all human-health-related aspects of both the natural environment and thebuilt environment. Environmental health concerns include:

• Air quality, including both ambient outdoor air and indoor air quality, which also comprises concerns about environmental tobacco smoke.
• Body art safety, including tattooing, body piercing and permanent cosmetics.
• Climate change and its effects on health.
• Disaster preparedness and response.
• Food safety, including in agriculture, transportation, food processing, wholesale and retail distribution and sale.
• Hazardous materials management, including hazardous waste management, contaminated site remediation, the prevention of leaks from underground storage tanks and the prevention of hazardous materials releases to the environment and responses to emergency situations resulting from such releases.
• Housing, including substandard housing abatement and the inspection of jails and prisons.
• Childhood lead poisoning prevention.
• Land use planning, including smart growth.
• Liquid waste disposal, including city wastewater treatment plants and on-site waste water disposal systems, such as septic tank systems and chemical toilets.
• Medical waste management and disposal.
• Noise pollution control.
• Occupational health and industrial hygiene.
• Radiological health, including exposure to ionizing radiation from X-rays or radioactive isotopes.
• Recreational water illness prevention, including from swimming pools, spas and ocean and freshwater bathing places.
• Safe drinking water.
• Solid waste management, including landfills, recycling facilities, composting and solid waste transfer stations.
• Toxic chemical exposure whether in consumer products, housing, workplaces, air, water or soil.
• Vector control, including the control of mosquitoes, rodents, flies, cockroaches and other animals that may transmit pathogens.

According to recent estimates, about 5 to 10 % of disability adjusted life years (DALY) lost are due to environmental causes in Europe. By far the most important factor is fine particulate matter pollution in urban air.^[4] Similarly, environmental exposures have been estimated to contribute to 4.9 million (8.7%) deaths and 86 million (5.7%) DALYs globally.^[5]

Information

The Toxicology and Environmental Health Information Program (TEHIP)^[6] at the United States National Library of Medicine (NLM) maintains a comprehensive toxicology and environmental health web site that includes access to resources produced by TEHIP and by other government agencies and organizations. This web site includes links to databases, bibliographies, tutorials, and other scientific and consumer-oriented resources. TEHIP also is responsible for the Toxicology Data Network (TOXNET),^[7] an integrated system of toxicology and environmental health databases that are available free of charge on the web.

Mapping

There are many environmental health mapping tools. TOXMAP is a Geographic Information System (GIS) from the Division of Specialized Information Services^[8] of the United States National Library of Medicine (NLM) that uses maps of the United States to help users visually explore data from the United States Environmental Protection Agency's (EPA) Toxics Release Inventory and Superfund Basic Research Programs. TOXMAP is a resource funded by the US Federal Government. TOXMAP's chemical and environmental health information is taken from NLM's Toxicology Data Network (TOXNET)^[9] and PubMed, and from other authoritative sources.