Toxic Floodwaters: Public Health Risks and Vulnerability to Chemical Spills Triggered by Extreme Weather

Coastal communities in the United States are largely unprepared for the projected effects of the climate crisis, including more intense storm surges, sea level rise, increased precipitation, and other drivers of coastal and inland flooding. That flooding is damaging enough on its own, but in recent years, chemical spills triggered by extreme weather, such as hurricanes, have become more frequent, exposing nearby communities to toxic chemicals and hazardous waste in the midst of natural disaster. Extreme weather-related flooding already has a variety of negative public health impacts, including injury, exposure to pathogens and mold, stress, and displacement. Chemical and hazardous waste spills may exacerbate and cause harms such as dermatitis, rashes, burns, headaches, fatigue, abdominal pain, fever, decreased appetite, nausea, sore throat, and eye irritation.

Unfortunately, federal and state governments have failed to develop regulatory safeguards that would prevent chemical spills in the event of these predictable extreme storms. That needs to change. Federal and state agencies should review the many permitted facilities at risk of flooding and focus inspections, outreach, technical assistance, and compliance resources on the most vulnerable facilities. As deemed necessary, agencies should reform regulations and permit programs for industrial facilities to account for future flood risks. State agencies should also assess risks to communities at the fenceline of hazardous facilities and take action to protect these vulnerable communities from harm.

As the effects of climate change amplify, changing patterns in hurricanes, precipitation, and sea level rise will increase both the intensity and frequency of storm surges and coastal flooding in the United States.[1]^,[2]^,[3]^,[4] According to the National Oceanic and Atmospheric Administration (NOAA), the regions most vulnerable to flooding and sea level rise are the Gulf Coast, Eastern Seaboard (especially Southeastern states), and the Pacific Northwest.[5] The social and economic implications of these projections are significant. More than half of the U.S. population (164 million people) lives or works in coastal counties, generating 58 percent of the nation’s GDP.[6]

The health effects of extreme weather-related chemical releases are difficult to predict with accuracy because communities are exposed to different mixtures of chemicals that, when released and combined with whatever else is present in floodwaters, may produce a variety of effects.[23] People also respond differently to chemical exposure. A study of hurricane-related chemical releases from facilities in Louisiana and Texas in 2005 found that 197 different hazardous substances were released in 166 events.[24] In most cases, only one hazardous substance was released per event, but in some instances, as many as eight were released. Among the more common toxicants released are volatile organic compounds (VOCs), polyaromatic hydrocarbons (PAHs), petroleum, and heavy metals.[25]^,[26] Floodwaters may also stir up existing contaminants present in soil and waterways, forming a “toxic soup.”[27]

The following health outcomes have been reported from flood-related chemical exposure: dermatitis, rashes, burns, headaches, fatigue, abdominal pain, fever, decreased appetite, nausea, sore throat, and eye irritation.[28]^,[29]^,[30] Some contaminants, like heavy metals, may also adsorb to sediments and redistribute throughout an area with floodwaters.[31]^,[32] For example, researchers found elevated levels of lead and arsenic in soil samples following Hurricanes Katrina and Sandy.[33]

Emergency response and clean-up workers are also exposed to hazardous pollutants. Some hydrocarbons can damage neoprene protective wear, and wetsuits may increase skin contact with chemical contaminants.[34] In a survey of New Orleans firefighters three months after Hurricane Katrina, 38 percent reported one or more respiratory symptoms and almost half— most of whom had contact with floodwaters—reported skin rashes.[35] Workers performing post-disaster repairs or demolitions can also inhale dust containing chemical contaminants and heavy metals. Another study, this one of New Orleans construction workers, noted elevated cases of pneumonia, asthma, and transient fever and cough following Hurricane Katrina.[36]

Due to a legacy of redlining, exclusionary zoning practices, and other systematic forms of housing segregation, the vast majority of people who live near chemical facilities are Black, Hispanic, and have low wealth.[37]^,[38] These communities often grapple with a range of social stressors, such as higher rates of chronic disease, inadequate access to health care, substandard housing, and racism-related stress.[39]^,[40] The cumulative burden of socioeconomic stress, flooding, and pollution from chemical facilities exposes these families to a greater risk of “debilitating damage, uncompensated loss, and long-term suffering.”[41] Children, the elderly, incarcerated people, and people with disabilities are also vulnerable to harm from floods.[42]

For example, when Hurricane Florence hit North Carolina in 2018, inadequate safety measures led to releases of coal ash and caused hog waste "lagoons" to overflow into nearby communities.[43] Research shows that industrial hog facilities are disproportionately permitted near communities of color in North Carolina, and for years before the hurricane, health outcomes have been worse among residents living near hog concentrated animal feeding operations (CAFOs).[44]^,[45] Flooding and exposure to more toxic contaminants only worsened the existing burden felt by these communities.

Since it is difficult to control the effects of extreme weather-related chemical spills, experts recommend a preventative approach to protect public health.[46] Researchers also project these events to become more frequent, “whether due to more development in hazardous areas, anthropogenic climate change, or natural variation.”[47] While awareness of these events has grown over the last decade, they are inadequately regulated at the federal, state, and local level.[48] Currently, neither the Occupational Safety and Health Administration (OSHA) nor the Environmental Protection Agency (EPA) require facilities to comprehensively address extreme weather and flood risks in required pollution prevention and management programs.[49] Furthermore, few states address flood risks in the permitting of industrial facilities.

The effects of climate change are upon us, and recent extreme weather events provide ample evidence of the folly of leaving toxic chemicals in the path of perfectly predictable floodwaters. Regulators should utilize their authority under state and federal law to prevent and mitigate climate-driven disasters by:

• Prioritizing inspection and enforcement in the most socially vulnerable communities;
• Ensuring that remediation plans submitted by brownfields developers are responsive to the potential risk of contamination from flooding;
• Improving public access to information about potential chemical hazards; and
• Ensuring that facilities comply with hazardous chemical reporting requirements.

Lawmakers should establish and fund programs creating siting, construction, and monitoring standards for above-ground hazardous chemical storage tanks and other unregulated chemical facilities exposed to extreme weather and flood risks.

Learn more about CPR's Toxic Floodwaters program.