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ENVIRONMENTAL HEALTH CONCERNS AND TOXIC CHEMICALS WHERE YOU LIVE, WORK, AND PLAY

Natural Disasters

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Natural disasters are events caused by nature, such as floods, hurricanes, droughts, and wildfires, that cause great damage, loss of life, and health-threatening pollution. These events can also be affected or made worse by human activity. 

What are they?

Droughts are an extended period of abnormally dry weather that lasts long enough to result in water shortages, dry soil, and crop damage. Droughts can last from one season to several decades and can affect up to millions of square miles of land.

Droughts are caused by a lack of rain or snow and can also be affected by the natural and man-made environment and local demand for water. Droughts can be aggravated by urban sprawl and development created without regard to water supplies and systems.

Why are they a concern?

Droughts can have economic, public health, and environmental impacts. Crop failures may affect the quality, amount, and price of food. Drought conditions may also affect the timber, ranching, shipping, boating, and fishing industries. 

Low water levels in lakes, rivers, streams, groundwater, and aquifers may compromise the amount and quality of drinking water during a drought. These conditions may also cause an increase in infectious disease. 

The risk of wildfires and dust storms increases during a drought. Severe drought conditions can also affect air quality.

What pollutants are of greatest concern and who is at risk?

Drought may expose people to Valley Fever, which is caused by fungal spores in desert soil. Drought can also increase diseases resulting from bacteria in drinking water, food, and stagnant water. Stagnant water is also more favorable for mosquitoes, particularly those that harbor West Nile virus. 

Particulate matter from dry conditions, wildfires, and dust storms can irritate human respiratory systems. Dry forms of pesticides can be blown by the wind. These pesticides can accumulate and be washed away in concentrated amounts when the drought ends.

Drought conditions may pose more serious risks for children, pregnant women, and older adults. People with chronic conditions such as asthma and immune disorders, and people who depend on drinking water from private wells, may also be at greater risk for harm from drought.
 

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What are they?

Dust storms are moving walls of fine particles of matter and debris that usually arrive suddenly. Dust storms form in dry regions when dust particles and fine-grained soils are blown into the air, often lifted by strong winds. Dust storms can be up to 100 miles wide and several thousand feet high. They travel an average of 25 to 50 miles. 

Dust storms are common in the U.S. Southwest during the region’s summer monsoon season, when winds shift, temperatures rise, and conditions are extremely dry. Powered by intense ground heating, thunderstorms can produce strong downdrafts. These downdrafts blow up loose sand on the desert floor, creating a dust storm.

Why are they a concern?

Dust storms can affect areas for days and even up to months. Exposure to dust in dust storms can affect air quality and cause coughing, wheezing, and runny noses. Breathing a lot of dust over a long period may cause chronic breathing and lung problems. 

 

Dust storms can have a significant effect on agriculture by damaging crops and harming livestock. They can blow away valuable topsoil, cause erosion, and reduce the land’s nutrients and water-holding capacity. 

 

Dust storms reduce visibility, at times to zero. They can make driving hazardous, cause accidents, and force airports to close. Dust storms can take down power lines, cause power failures, and damage infrastructure. The buildup of dust can affect computers and communications equipment.
 

What pollutants are of greatest concern and who is at risk?

Dust storms can contain particulate matter, which can be a serious threat to human health if it builds up in the respiratory system, particularly for people with asthma.

Dust storms may expose people to fungal spores that can cause the disease Valley Fever. Native Americans, Hispanics, and African Americans are more likely to develop an infection from Valley Fever.

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What are they?

Severe storms include thunderstorms, heavy rains, strong winds, hurricanes and cyclones, and storm surge. Catastrophic flooding can be caused by any severe storm or by a tsunami, an ocean wave produced by an earthquake, landslide, or volcanic eruption. Tsunamis can travel across entire oceans and cause severe flooding when they make landfall.

Why are they a concern?

Severe storms and floods can cause drowning, injuries, and contamination. If polluted floodwaters linger after a storm, there is the possibility of infection from wading in the floodwaters or using the water for drinking and cooking. Flooding may also leave pools of water favorable to mosquitoes that transmit disease. 

Evacuations may be necessary before a severe storm. A storm can damage homes and buildings, forcing people to seek shelter during and after the storm. If you leave your home, don’t return until you are told it is safe to do so. 

What pollutants are of greatest concern and who is at risk?

Severe storms and floods can create solid waste, debris, and polluted floodwater, which can contaminate drinking water, soil, and food with toxic chemicals. Storms and floods can cause power failures, threaten above-ground and underground storage tanks, and make roads and bridges unsafe. Damaged or flooded septic systems or wastewater treatment facilities can result in raw sewage contaminating flood water. A flooded septic system can contaminate nearby drinking water sources. 

 

After a flood, electrical power, natural gas, and propane tanks can pose a risk of fire, electrocution, or explosions. Emergency generators can emit dangerously high levels of carbon monoxide and must be used or vented outside. 

 

After a flood, mold may grow on household materials and belongings that are wet. Mold can cause difficulty breathing, irritated eyes and skin, and other health problems. 

 

Anyone in an environment where a severe storm or flood has occurred is at risk for harm.
 

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What are they?

Wildfires are unplanned, destructive fires that rapidly spread out of control, especially in the wilderness or rural areas. They can be started by lightning, human activity, sparks from falling rocks, or volcanic activity. They also can result when a planned fire set to manage forests or agricultural lands spreads unexpectedly.

Why are they a concern?

Wildfires can threaten human life, natural resources, and property. Wildfires can lead to erosion, landslides, and the introduction of invasive species. Sediment, burned debris, and chemicals resulting from wildfires can affect water quality.

Wildfire smoke is made up of a complex mixture of gases and fine particles from burning trees and other plant materials. Exposure to wildfire smoke can cause: 

  • Bronchitis
  • Headaches
  • Reduced lung function
  • Stinging eyes, nose, and throat
  • Tightness or pain in the chest
  • Wheezing, coughing, and shortness of breath

What pollutants are of greatest concern and who is at risk?

The biggest threat to human health from wildfire smoke comes from the smoke’s particulate matter. The smoldering phase of a wildfire can result in very high levels of fine particle emissions.
Wildfire smoke contains: 

Older adults, children, and people with heart or lung disease are more likely to be affected by wildfire smoke. Firefighters have increased occupational risk of exposure to smoke-related health hazards. Exposure to wildfire smoke may worsen symptoms of asthma, respiratory allergies, and chronic obstructive pulmonary disease.
 

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Reduce your risk

  • Do you live in an area prone to natural disasters?
  • Do you have a family emergency evacuation plan?
  • Do you have an emergency kit prepared?
  • Review Air Quality Index Reports for your area .
  • Learn about your community’s emergency plans, warning signals, evacuation routes, and emergency shelters.
  • In the event of an emergency, listen to local radio and follow all warnings and calls for evacuation or sheltering in place.
  • Have an emergency escape route ready, and practice the plan with your family.
  • Keep an emergency kit at home,  in your car, and at your workplace. Contents should include:
    • Prescription medications; non-prescription medications you might need, such as pain relievers
    • Enough nonperishable food and water to last at least three days
    • A first aid kit
    • A flashlight and extra batteries
    • A battery-powered radio
    • Respiratory  and eye protection
    • Sturdy shoes
    • A manual can opener
  • Prepare copies of important personal and family documents, and store them in a secure location.
  • Post emergency phone numbers at every phone.
  • Have fire extinguishers in your home and know how to use them.
  • If you live in an area prone to earthquakes, practice drills. Drop down onto your hands and knees, cover your head and neck, and hold on to your shelter.
  • Find additional resources at the Centers for Disease Control and Prevention, Office of Public Health Preparedness and Response.
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