Environmental health is the branch of public health concerned with all aspects of the natural and built environment affecting human health. Its study determines the requirements for a healthy environment, with the goal of effective control over the factors that affect health. The major sub-disciplines of environmental health are environmental science, toxicology, environmental epidemiology, and environmental and occupational medicine.
Definitions WHO definitions Environmental health was defined in a 1989 document by the World Health Organization (WHO) as: Those aspects of human health and disease that are determined by factors in the environment. It is also referred to as the theory and practice of assessing and controlling factors in the environment that can potentially affect health.
, the WHO website on environmental health states that "Environmental health addresses all the physical, chemical, and biological factors external to a person, and all the related factors impacting behaviours. It encompasses the assessment and control of those environmental factors that can potentially affect health. It is targeted towards preventing disease and creating health-supportive environments. This definition excludes behaviour not related to the environment, as well as behaviour related to the social and cultural environment, as well as genetics."
Environmental health also looks at how exposure to things like air pollution, water contamination, and chemicals can affect people's health over time.
Other considerations The term environmental medicine may be seen as a medical specialty, or a branch of the broader field of environmental health. Terminology is not fully established, and in many European countries these are used interchangeably.
Other terms referring to or concerning environmental health include environmental public health and health protection.
+Comparison of integrated approach in healthOriginsConceptEnvironmental healthFrom the 1880s Sanitary Science Anthropocentric approach on environment influence on human health.One Health (legacy)Virchow and Osler (1800s) and Schwabe (1964) zoonosis Collaboration of human medicine and veterinary.One Medicine–One Health (modern)Early 2000s as response to emerging infectious diseases (SARS, MERS, Ebola) Cross-sectoral and transdisciplinary collaboration to improve health of humans, animals and ecosystems because of inter-connectedness. Recognizes the interconnectedness of human, animal, and environmental health. Incorporates components of food safety, antimicrobial resistance, and environmental contaminations.Conservation medicine1990s as health gains importance in conservation Connection of health of animals and humans and ecosystems in situComparative medicineSince ancient time Understanding shared or similar pathophysiological processes, which is fundamentals for medical and translational researchEcohealth1990s by French Canadian-based International Development Research Centre Dependency of human and animal health and wellbeing on sustained environment. Human and ecosystem health exists in socio-ecological interactionsPlanetary healthIntroduced in 1970–80s, and repopularized by Lancet Commission and Rockefeller Foundation Anthropomorphized view of impact and interconnectedness of humans with the Earth at all levelsOne WelfareEmerged in 2015 for promotion of the links between animal welfare and human wellbeing Highlights the interconnection of animal welfare, human wellbeing, and environment to foster interdisciplinary collaboration in order to improve human and animal welfareBeyond One Ocean Health (B1OH)Impacts of environmental change on health of ecosystems and organisms with emphasis on ocean Highlights transdisciplinary actions on aquatic ecosystems, interconnected integrated systems and health through sustainable developments Links healthy ocean with health and equity.Public health Population-based (instead of individual) Focus on health promotion and prevention (instead of treatment and rehabilitation) Social, cultural, economic, political, and environmental determinant of healthGlobal healthSupraterritoriality of health Transboundary health threats
Disciplines
Five basic disciplines generally contribute to the field of environmental health, with some overlap between 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. Environmental epidemiology is the study of the effect on human health of physical, biologic, and chemical factors in the external environment, broadly conceived. Also, examining specific populations or communities exposed to different ambient environments, Epidemiology in our environment aims to clarify the relationship that exist between physical, biologic or chemical factors and human health. 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 it 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. Environmental engineering applies scientific and engineering principles for protection of human populations from the effects of adverse environmental factors; protection of environments from potentially deleterious effects of natural and human activities; and general improvement of environmental quality. Environmental law includes the network of treaties, statutes, regulations, common and customary laws addressing the effects of human activity on the natural environment.
Information from epidemiology, toxicology, and exposure science can be combined to conduct a risk assessment for specific chemicals, mixtures of chemicals or other risk factors to determine whether an exposure poses significant risk to human health (exposure would likely result in the development of pollution-related diseases). 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. Intervention strategies from engineering and law can be combined to provide monitoring and risk management of exposure, and achieve the objective of protecting human health.
Pediatric environmental health Children's environmental health is the academic discipline that studies how environmental exposures in early life—chemical, biological, nutritional, and social—influence health and development in childhood and across the entire human life span. Pediatric environmental health is based on the recognition that children are not "little adults." Infants and children have unique patterns of exposure and vulnerabilities. Environmental risks of infants and children are qualitatively and quantitatively different from those of adults. Pediatric environmental health is highly interdisciplinary. It spans and brings together general pediatrics and numerous pediatric subspecialties as well as epidemiology, occupational and environmental medicine, medical toxicology, industrial hygiene, and exposure science.
Concerns
Environmental health concerns include: Biosafety. Disaster preparedness and response. Food safety, including in agriculture, transportation, food processing, wholesale and retail distribution and sale. 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 waste water treatment plants and on-site waste water disposal systems, such as septic tank systems and chemical toilets. Medical waste management and disposal. 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. 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. Toxins from molds and algal blooms. Vector control, including the control of mosquitoes, rodents, flies, cockroaches and other animals that may transmit pathogens.
According to recent estimates in Europe, about 5 to 10% of disability-adjusted life years (DALYs) lost are due to environmental causes. By far the most important factor is fine particulate matter pollution in urban air. Similarly, environmental exposures have been estimated to contribute to 4.9 million (8.7%) deaths and 86 million (5.7%) DALYs globally. In the United States, Superfund sites created by various companies have been found to be hazardous to human and environmental health in nearby communities. It was this perceived threat, raising the specter of miscarriages, mutations, birth defects, and cancers that most frightened the public.
Air quality Air quality includes ambient outdoor air quality and indoor air quality. Large concerns about air quality include environmental tobacco smoke, air pollution by forms of chemical waste, and other concerns.
Outdoor air quality Air pollution is globally responsible for over 6.5 million deaths each year, as of 2022. Air pollution is often a risk-factor for diseases like lung cancer, respiratory infections, asthma, heart disease, and other forms of respiratory-related illnesses. Reducing air pollution, and thus developing air quality, has been found to decrease adult mortality.
Common products responsible for emissions include road traffic, energy production, household combustion, aviation and motor vehicles, and other forms of pollutants. These pollutants are responsible for the burning of fuel, which can release harmful particles into the air that humans and other living organisms can inhale or ingest.