MA EPHT - Climate and Health Pathways

Climate and health pathways describe links between climate change and health.

The Climate Change Conceptual Pathway table shows the relationships between climate change drivers, environmental exposures, and their health impacts.

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Heat

Hazard: heat events:

• More frequent
• Longer duration
• More extreme

Exposures	Vulnerable Groups	Health Risks
Elevated temperatures	People over age 65 People over age 65 and living alone Children under age 5 People with preexisting conditions: Diabetes Cardiovascular disease Renal system disease People of color1 People working or exercising outdoors People with limited English proficiency	Heat Exhaustion Heat Stroke Illness or death due to cardiovascular disease Illness or death due to renal system failure

Hazard: poor outdoor air quality:

• Increases in ozone
• Increases in particulate matter
• Increased pollen production
• Longer pollen season

Exposures	Vulnerable Groups	Health Risks
Ozone, Particulate Matter	People over age 65 Children under age 5 People with pre-existing conditions: asthma, COPD, respiratory allergies, cardiovascular disease People working or exercising outdoors People with limited English proficiency	Respiratory arrest Exacerbation of asthma and other lung disease Exacerbation of allergies and respiratory infections Reduction in childhood lung function development2
Pollen	People with allergies People with asthma	Exacerbation of asthma Allergy symptoms

Hazard: food-borne illness

Exposures	Vulnerable Groups	Health Risks
Spoiled food from refrigeration failure in transport/storage	People over age 65 Children under age 5 Pregnant women People with compromised immune systems	Gastrointestinal illness
Changes in patterns of salmonella growth	People over age 65 Children under age 5 Pregnant women People with compromised immune systems	Salmonella infection

Hazard: drought

Exposures	Vulnerable Groups	Health Risks
Water quality degradation	People over age 65 Children under age 5 Pregnant women People with compromised immune systems	Gastrointestinal Illness Nitrate exposure Naturally occurring arsenic and uranium exposure3

Heat and increased precipitation combined

Hazard: vectorborne disease

• Longer seasons
• Expanding ranges
• Increased habitat
• Higher breeding rates

Exposures	Vulnerable Groups	Health Risks
Ticks	People working or exercising outdoors People with pets that go outdoors	Tick-borne illnesses (e.g. Lyme, Babesiosis, Anaplasmosis)
Mosquitoes	People working or exercising outdoors	West Nile Virus Eastern Equine Encephalitis

Hazard: biological contamination of water

Exposures	Vulnerable Groups	Health Risks
Contact with water contaminated with fecal bacteria (e.g. E. Coli or salmonella) from runoff, flooding, or sewer overflow discharge4	People over age 65 Children under age 5 Pregnant women People with compromised immune systems	Skin infections Eye infections Wound infections Gastrointestinal Illness
Water or shellfish contaminated with Vibrio bacteria (e.g. Vibrio vulnificus, Vibrio parahaemolyticus)5	People over age 65 Children under age 5 Pregnant women People with compromised immune systems People with liver disease or Thalassemia People who consume raw shellfish People who take medications that decrease stomach acid levels	Gastrointestinal illness Wound infection Septicemia (bloodstream infection)
Contact with Algae Blooms (Cyanobacteria)6	Children under age 5 People who boat or swim in fresh water lakes, ponds, and rivers Pets	Gastrointestinal symptoms Skin and eye irritation Neurological damage Liver damage

Hazard: chemical contamination of water

Exposures	Vulnerable Groups	Health Risks
Contact with chemically contaminated water from flooding and runoff	People over age 65 Children under age 5 Pregnant women	Skin reactions Chronic Illness

Flooding (inland and coastal)

Hazard: all flooding

Exposures	Vulnerable Groups	Health Risks
Contaminated flood water (direct contact or flood-contaminated drinking water)	People over age 65 Children under age 5 Pregnant women People with compromised immune systems People with limited English proficiency	Skin infections Eye infections Wound infections Trench foot Gastrointestinal illness
Debris/Physical hazards	Adolescents and Young Adults7 Utility workers Rescue workers	Injury or death from debris, downed wires, drowning, falls, and motor vehicle crashes
Loss of Electricity, heat	People over age 65 People living alone Children under age 5 People using medical equipment that requires electrical power or medications that require refrigeration	Carbon Monoxide (CO) Poisoning Falls and injuries in the home Medical emergencies due to loss of medical equipment function Medical emergencies due to spoiled medications
Relocation/Displacement	People over age 65 People with limited mobility People under age 18 People with low socioeconomic status People who rent their homes People with limited English proficiency People of color	Psychological stress Financial loss stress Loss of employment Substance abuse
Mold	Children under age 5 People with compromised immune systems or respiratory disease People with Allergies People with Asthma	Allergic reactions Respiratory illness

Hazard: all flooding

Exposures	Vulnerable Groups	Health Risks
Salinization of land leading to loss of shade cover and green space	People susceptible to heat-related illness (see groups vulnerable to heat events)	Heat-related illnesses (see heat related health risks)
Salt intrusion into drinking water supplies	People with hypertension or other salt-sensitive illnesses/medications	Hypertension Medication interactions

Extreme weather

Hazard: damage to critical infrastructure

Exposures	Vulnerable Groups	Health Risks
Loss of electricity, heat	People over age 65 People living alone Children under age 5 People using medical equipment that requires electrical power or medications that require refrigeration	Hypothermia Carbon Monoxide (CO) Poisoning Falls and injuries in the home Medical emergencies due to loss of medical equipment function Medical emergencies due to spoiled medications
Loss of water and sewer/septic utilities	People over age 65 Children under age 5 Pregnant women People with compromised immune systems People with limited English fluency	Gastrointestinal illness Dehydration
Damage to roadways	People over age 65 People living alone Children under age 5 Pregnant women People with limited mobility People with chronic medical conditions requiring frequent care	Death or injury due to delayed emergency response Motor vehicle accidents/injuries

Hazard: direct storm impacts

Exposures	Vulnerable Groups	Health Risks
Debris/Physical hazards	Adolescents and Young Adults7 Utility workers Rescue workers	Injury or death from debris, downed wires, falling trees, falls, and motor vehicle crashes

Sources

1. Hattis D, Ogneva-Himmelberger Y, Ratick S. The spatial variability of heat-related mortality in Massachusetts. Applied Geography 33 (2012) 45-52.
2. Gauderman WJ, Avol E, Gilliland F, Vora H, Thomas D, Berhane K, McConnell R, Kuenzli N, Lurmann F, Rappaport E, Margolis H, Bates D, Peters J. The effect of air pollution on lung development from 10 to 18 years of age. N Engl J Med. 2004 Sep 9;351(11):1057-67.
3. USGS Uranium and Arsenic Bedrock Well Study for Massachusetts on Mass.gov.
4. Lowe D, Ebi KL, Forsberg B. Factors Increasing Vulnerability to Health Effects before, during and after Floods. Int. J. Environ. Res. Public Health 2013, 10, 7015-7067.