Environmental and Occupational Health Chapter 8 Environment s role in etiology how disease happens Germ theory of disease widely accepted in late 1800s Public health efforts in 19th century focused primarily on environmental sanitation Miasma theory of disease Most medical scientists had shifted their efforts from the identification of social and environmental risk factors for disease to the identification of specific infectious agents and genes Scientists health professionals and health consumers agree there are many social behavioral environmental and biological contributors to disease Modern environmental health scientists access the impact of people on their environment and the impact of environment on human health Environmental health looks at all aspects of physical environment Physical environment impacts health behavior Environmental health researchers focus on issues related to geography geology and climate Health risks are often tied to local climate types of vegetation and animals Most environmental health experts focus on aspects of health related to the home workplace or community Home Environment environment Environmental health is also concerned with the health and safety of the home Most building have potential health hazards Conditions may be potentially hazardous but in some ways it is a luxury to be able to worry about these household threats Contaminated water poor sanitation and hygiene and inadequate management of human and animal waste are all associated with increased risk of diarrheal diseases and other infections Air pollution including the indoor air pollution is associated with respiratory infections chronic diseases Increasing access to healthy housing improved health Drinking Water Everyone needs access to an adequate supply of clean water Increased access to water is associated with improved health When water sources are far from home women spend a lot of time getting it Five key aspects of water access o Quality water must be clean enough to drink safely o Quantity must be available so people can stay hydrated and clean o Reliability the water source must be available and functioning at all times Appropriate technology simple enough that if broken it can be repaired by local residents cheaply and quickly o Cost water must be affordable Access to water is requirement for life Sanitation Sanitation is disposal of human excreta Several types of sanitation facilities that can be used for safe waste disposal Simple pit latrine hole in ground covered buy an outhouse or enriched by privacy blind Septic tanks and sewer connections are more advanced sanitation technologies Advanced sanitation facilities are common in north America and Europe About half of the people who live in developing countries do not have access even to simplelest improved sanitation facility Must practice open defecation Some people may be able to go to defecation site away from home People who do not have improved sanitation system are at increased risk for infectious diseases Six Fs o Feces are not exposed properly they can contaminate fields and fluids Fecal matter can then get onto hands and fingers and transport it to foods Flies can spread it to foods too Presence of feces near homes significantly increases the risk of bacterial viral and protzoal diarrheal diseases and helminthic worm infections Fuel and Indoor Air Quality Energy is necessary for at least 3 important purposes cooking food and boiling water for safe consumption providing a source of heat when outdoor temperatures are low and providing source of light at night Households without electricity usually rely on sold fuels All fuels that are burned for energy release air pollutions Solid fuels used in homes are particularly unhealthy Use of solid fuels can have other negative health effects risk for burns susceptible to injuries Several ways people can reduce exposure to indoor air pollution o Improved cooking devices o Increase ventilation or move the kitchen to the outside o Change behavior Work Environment Occupational health was one of the first public health specialty fields Every worker may face a particular mix of biological chemical physical mechanical and Toxicology study of harmful effects that chemicals and other environmental hazards like psychosocial challenges at work Toxicology radiation can have on living things influences health Variations in exposure frequency duration dose various exposure routes and how it Carcinogens cause genetic mutations that lead to cancer Teratogens cause birth defects Ecotoxicology examines impact of toxic exposure on populations communities and ecosystems Air pollution is a widespread environmental damage caused by humans Many countries have passed occupational and environmental health and safety laws Communities and environmental health Everyone who lives or works in a community share the same air water and environmental exposure WHO endorses the use of indoor residual spraying IRS for mosquito control in areas that have endemic or epidemic malaria transmission Chapter 14 347 357 Disasters and Health Both natural and human generated disasters lead to urgent humanitarian situations Critical needs o Water o Food o Shelter o Essential health services Crisis small scale event that can be addressed locally Emergency larger event that stresses local resources but can be managed locally Disaster occurs when need exceed local capacity Catastrophe overwhelms the local response network and requires extensive outside Attention must be paid to protecting the civil political economic social and cultural assistance rights of affected persons Nonderogable right human right that is irrevocable If rights are derogated during or immediately after critical incident the new rules must not be discriminatory and full rights should be restored as soon as possible Civil Conflict and War Complex humanitarian emergency occurs when civil conflict or war cause mass migration of civilian populations food insecurity and long term public health concerns International humanitarian laws are supposed to provide protection to civilians and armed forces Malnutrition is primary concern during conflicts Outbreaks of communicable diseases also often occur during complex emergencies Refugees and Internally Displaced People Refugee person who has been forced to involuntarily move because security concerns o Services are often provided in camps Refugee means they crossed a border Internally displaced person IDP