Ground-level Ozone is a colorless, reactive gas that forms through atmospheric chemical reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the presence of sunlight. Ozone is typically emitted through sources such as vehicles, industrial facilities, and electric utilities. High concentrations of Ozone typically occur on hot, sunny spring and summer days when the air is stagnant, creating breathing problems for children, people with asthma or respiratory conditions, and adults working or exercising outdoors. 

Particulate Matter (PM) consists of tiny solid particles and liquid droplets in the air from vehicle emissions, industrial facilities, wood burning, and dust. The smallest particles—PM2.5—pose the greatest health risk, as particles can penetrate deep into the lungs and enter the bloodstream, causing serious respiratory and cardiovascular problems.

Carbon Monoxide (CO) is a colorless, odorless gas that can be harmful when inhaled in large amounts. CO is released when something is burned. The greatest sources of CO to outdoor air are cars, trucks and other vehicles or machinery that burn fossil fuels. A variety of items in your home such as unvented kerosene and gas space heaters, leaking chimneys and furnaces, and gas stoves also release CO and can affect air quality indoors.

Lead is a naturally occurring element present in small amounts in the Earth’s crust. Although it has some beneficial uses, lead is toxic to humans and animals. It is found throughout the environment, including air, soil, water, and inside homes. Most exposure results from human activities such as the historical use of leaded gasoline, certain industrial processes, and lead-based paint in homes. Lead, and its compounds have been used in products such as paint, ceramics, plumbing materials, gasoline, batteries, ammunition, and cosmetics. Federal and state regulations have reduced lead levels in air, water, soil, consumer products, food, and workplaces. Children and adults, especially pregnant women, are most at risk for lead exposure, which can cause birth defects, miscarriage, cardiovascular and reproductive issues, and learning and behavioral problems.

Sulfur Dioxide (SO2) is a colorless gas released primarily from burning coal and oil at power plants and industrial facilities. Short-term exposure can cause breathing difficulties and respiratory problems, especially for children and people with asthma. SO2 also contributes to particulate matter pollution that can penetrate deep into the lungs.

Nitrogen Dioxide (NO2) is a reactive gas produced from vehicle emissions, power plants, and fuel combustion. Exposure can irritate airways and aggravate respiratory diseases like asthma, with children and the elderly. NO2 also contributes to particulate matter, ozone formation, and acid rain.

Asbestos is a naturally occurring mineral fiber once widely used in building materials for insulation and fire resistance. When disturbed during demolition, renovation, or repairs, asbestos fibers can become airborne and cause serious lung diseases including mesothelioma. Proper handling and professional removal are essential for safety.

Ethylene Oxide (commonly referred to as EtO) is a highly versatile, flammable gas used to manufacture a range of consumer products such as plastics, textiles, adhesives, detergents and antifreeze. It is also utilized in the sterilization of medical and dental equipment and plastic devices that cannot be sterilized by steam. According to the EPA, exposure to high concentrations of EtO over a short period of time can result in various health problems. These may include headache, dizziness, nausea, fatigue, respiratory irritation such as coughing, wheezing and shortness of breath, and in some cases, vomiting and gastrointestinal distress. 

Mercury is a naturally occurring element that is found in air, water, and soil. It exists in several forms –elemental (also known as metallic mercury), inorganic, and organic. Mercury is a liquid metal that easily evaporates, giving off invisible, odorless, and toxic vapors. Mercury is released into the environment from both natural and human sources. It becomes airborne through rock erosion, volcanic eruptions, and soil decomposition, then circulates in the atmosphere. Human activities, including burning fossil fuels, incinerating waste, and mining, also release mercury. Once airborne, mercury returns to the ground with rain or snow, contaminating soil and water. Mercury is toxic, and even small exposures can cause serious health problems. People may be exposed through skin contact, consuming contaminated fish, or inhaling mercury vapors.