Standard+4.3.10.a

Standard 4.310.A - Describe environmental health issues

Major environmental health issues include air pollution, water contamination, and indoor pollution


 * Air Pollution**

The earth's atmosphere is primarily composed of nitrogen, oxygen, argon, and carbon dioxide while minor components include methane and helium, along with thirteen other gases. Any substances that are not naturally found in the atmosphere are known as pollutants.

Ground-level ozone- Ozone is chemical that is composed of three oxygen atoms and although it is not normally released directly into the atmosphere ground-level ozone appears when a chemical reaction occurs between the oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. Although ozone in the upper atmosphere and ground-level ozone share the same chemical compound depending on their location in the atmosphere they can be "good ozone" or "bad ozone." "Good ozone" which makes up the ozone or stratospheric zone is usually located 10 to 30 miles above the earth's surface and acts as shield against ultraviolet radiation. "Bad ozone" or ground-level ozone is a primary component of smog and tends to appear in higher levels in urban areas due to an increase in the motor vehicle exhaust, industrial emissions, and chemical solvents that emit NOx and VOC. Wind can also cause ozone to form in rural areas causing pollutants to travel many miles from their source. Ground-level ozone has many negative health effects including worsening asthama and emphysema as well as reducing lung function. Symptoms such as chest pain, coughing,and congestion can result from short time exposure while more repeated exposure can permanently damage lung tissue. Vegetation and crops can also be damaged by this pollution causing plants more susceptible to disease and reduces crop yield. The Clean Air Act requires the EPA to set air quality standards to protect public health and agriculture (Ground-level Zone 2008).

Sulfur Dioxide- Sulfur dioxide forms when fuels containing sulfur such as coal and oil are burned releasing the gas into the atmosphere. Due to sulfur's highly solvable properties sulfur dioxide dissolve in water vapor to form acid which contributes to acid rain. Sulfur dioxide can contribute to respiratory diseases and aggravate preexisting lung and heart diseases. From 1990 to 2006 sulfur dioxide levels have decreased through the U.S. at an average of 53% and continue to drop (Sulfur Dioxide 2008).

There are many non-point and point pollution that contaminate our waters. Point pollutants or pollutants that can be traced back to a particular source include sewage and industrial waste while non-point pollutions are those that can not be traced to a particular point of entry such as agricultural runoff and storm water drainage. The most common water pollutants include pesticides, lead, and arsenic. Acid rain is a large water pollutant which can lead to the acidification of many bodies of water. Acid rain mostly effects bodies of water whose ecosystems are sensitive to acid and can lead to chronic acidity a condition where a body of water continuously has low pH levels. Acid rain can completely destroy ecosystems by making acid levels so high that no organisms can survive there. Pollution can also contaminate groundwater so to ensure safe drinking water the Clean Water Act ensures that the EPA regulates pollution levels in bodies of water and sets regulations for contaminate levels. The EPA is also working with organizations around the country to control non-point pollution. Contaminants in water can cause many water born diseases and illnesses (Water Pollutants 2008)
 * Water**

While most people spend approximately 80% to 90% percent of their lives indoors and many scientists feel that we are just as effected if not more effected then outdoor pollution by indoor pollution. The California Air Resource Board estimates that pollutant levels indoors are 25 to 65% higher indoors then outdoors. A major indoor pollution is radon, a natural radioactive gas that can be found in the basements of many Americans. Radon can be deadly and is estimated to be the second leading cause of lung cancer deaths in the United States. Another harmful indoor pollutant is secondhand smoke which comes from two sources side stream and mainstream smoke. Mainstream smoke is the smoke that is inhaled by the smoker and is exposed to a nonsmoker when they exhale and side stream smoke come directly from the end of the tobacco product. Secondhand smoke has been labeled as a Class A carcinogen by the EPA and causes significant numbers of deaths from lung cancer and cardiovascular disease every year. Biological pollutants which include fungi, dust mites, and pollen as well as many others and require both nutrients and moisture to thrive. The most common health problem associated with these pollutants is allergic reactions which can range from severe asthma to nasal congestion. Infectious diseases such as influenza and tuberculosis can be spread indoors as well as toxic reactions to some fungi and molds (Indoor Air Pollutants 2008).
 * Indoor Pollution**