Is climate change increasing toxicant exposure?
(Article originally published in the Townsend Letter Dec 2021)
Introduction
Climate change is having a powerful impact on the world. The direct effects are easy to see, from rising temperatures to extreme weather events to droughts. Scientists are now discovering that global climate change has indirect effects as well. Climate change is increasing exposure to toxicants and affecting the toxicity of chemicals. This could lead to an increase in health conditions linked to environmental exposures. It is a well-known fact that exposure to toxicants has both acute and chronic health effects. Acute conditions like cardiac arrhythmias and asthma can be attributed to air pollution for example. Chronic low dose exposure to toxicants in our air, food, water, and personal care products are linked to conditions such as cancer, hormonal disorders, auto-immune conditions, immunotoxicity, and chronic neurodegenerative diseases. Health care providers need to consider how climate change will alter exposures to pollutants, increase the routes and sources of exposure, and have effects on the toxicant itself. Now more than ever it is imperative that health providers consider the effects of environmental chemicals on patient’s health. Climate change is happening before our eyes, and it is already having an impact on toxicants in our food, water, and air.
Changes in our food due to global climate change
As temperatures rise, there are higher rates of bacterial growth in the soil and in the food supply. Insects and pest adapt to warmer temperatures and thrive causing damage to food crops. More herbicides and pesticides will be needed in agriculture due to these increases in pests, insects, disease, and weeds. This will lead to increased exposure to pesticides among farm workers who spray the crops, people who live near orchards and farms, as well as in consumers due to pesticide residue on food. 1,2 One study on the effects of climate change and food production predicted pesticide use on wheat will increase by 14% in Kansas and in Illinois pesticide use will increase by 18% on corn. 3 Higher temperatures may lead to more pathogens, vectors, or hosts resulting in greater use of biocides and veterinary medicines used in the animals we eat. This could increase of antibiotic-resistant pathogens in both animals and humans. Climate change also can lead to an increase in mycotoxin exposure from foods 3 Warmer temperatures lead to high amounts of carbon dioxide in the air which leads to lower levels of zinc, iron, protein, and other nutrients in crops. 1,2 Climate change will decrease the nutrient content of food. The use of more pesticides and herbicides on our food, the increased use of medications in animals, the increase in the presence of bacteria and mycotoxins in our food, and lower nutrient content of food, will eventually have adverse health effects.
Climate change is increasing the water temperature and altering the levels of oxygen in our rivers, lakes, and oceans. Several studies have already determined that these changes are increasing the concentration of methylmercury in the fish that people consume. Basically, climate change is increasing the amount of mercury in fish thus increasing another source of exposure of toxicants harmful to human health. In the past it was advised that people limit the amount of fish high in mercury to no more than once a month. Soon, due to the effect of climate change of the concentration of mercury in fish, people may have to completely avoid certain types of fish. 4,5
Choosing USDA organic foods can reduce the amount of pesticide residue consumed from fruits and vegetables and avoid exposure to antibiotics and hormones from meats and dairy. Avoiding or severely limiting fish known to be high in mercury is also advised as a means of avoiding toxicant exposure. Environmental Working Group frequently updates their list of fish high and low in mercury based on where the fish is sourced. www.ewg.org
Changes in our water due to global climate change
The increased use of pesticides and herbicides due to rising temperatures will contribute to an increase in contamination of nearby ground water. There will be more pesticide run-off in the water supply. Climate change will affect the amount of arsenic in the water and thus in the foods people consume. Arsenic is naturally occurring, in animal feed, and is still present in some pesticides. Higher temperatures release more arsenic from the soil. For example, under flood conditions arsenic is drawn out of soil into the water and rice being grown in that area takes up the arsenic. 7 Climate change will alter recharge events, lower water tables, and reduce groundwater flow. This will allow pesticides, arsenic, and other chemicals to seep into aquifers used for public drinking water. 6
The Environmental Protection Agency, EPA, warns that increased water temperatures will create more bacteria and algae blooms in water. Increases in extreme weather events such as storms and flooding will negatively impact water quality through pollutant runoff in to drinking water systems. This creates challenges for municipalities to regulate and keep the water safe for consumption. 8 As climate change brings rising temperatures it will vaporize chemicals, releasing them from soil or water and cause more harmful chemicals to dissolve in drinking water. Melting ice and snow can also release stored chemicals.
As global climate change affects water quality it is imperative that people frequently test their home water and use proper filtration for chemicals found in the water. Water testing can be done through https://watercheck.com/ Reverse osmosis filtration removes most toxicants and can be installed under the kitchen sink and used for cooking and drinking water. A whole house reverse osmosis system is probably the best method of filtration but not always feasible.
Changes in our air due to global climate change
In the US, the burning of fossil fuels to make electricity is the largest source of heat-trapping air pollution, producing about two billion tons of carbon dioxide, CO2, every year. Coal-burning power plants are the biggest air polluters. The second-largest source of carbon pollution is the transportation, which generates about 1.7 billion tons of CO2 emissions a year. Climate change means higher temperatures which will change precipitation patterns, create higher ocean acidity, and reduced sea-ice cover. All of this will have effects on concentrations of contaminants in the air. Especially increases in Ozone air pollution. 2 ,9 Increases in temperature will enhance the toxicity of contaminants and increase concentrations of ozone regionally. Low moisture conditions will produce toxic air particles, while high moisture will cause chemicals in the air to drop to the ground via rain or snow. 9
As the world warms up it has the potential to burn. Wildfires burning across the U.S. increases each year as does the proximity to major cities and towns. Some are man-made, both accidental and on purpose, and others are due to forces of nature like a lightning strike. Numerous toxic chemicals are released into the air when fires burn forests, fields, and towns. The health effects of the first responders are well documented but not as much attention to the effect on those living or working nearby. It’s important for physicians and health care providers to understand what chemicals are released when a wildfire burns. These toxicants can travel through the air contributing to respiratory conditions in vulnerable populations. Toxicants are released during wildfires that are known carcinogens, immunotoxins, endocrine disrupting compounds and can affect the pulmonary and cardiovascular system. 10
Climate change will significantly impact air quality in some areas of the U.S. more than others. In the Southwest where warmer and drier conditions are expected to continue there will be more dust storms transporting more toxicants and particulate matter in the air. What is interesting is that as particulate matter increases it can negatively affect the climate, creating climate changes. For example, soot can absorb heat and increase temperatures; sulphate particles can cool the climate and contribute to aerosol–cloud interactions. 11 These changes create poor air quality and hazardous chemicals in the air.
The health effects of poor air quality are well known. Air pollution is linked to cardiopulmonary and respiratory disease (e.g. asthma, chronic bronchitis, rhinitis), diabetes, rheumatic diseases, cognitive functioning, and neurodegenerative diseases. 12 Air filtration with Hepa filters is a way to eliminate some toxicants from indoor air. During period of high air pollution, it is advised that people avoid outdoor activities. People can track the air quality in their area at https://www.airnow.gov/
Changes in our health due to global climate change
According to the National Academy of Medicine, climate change is the biggest threat to human health this century. Not everyone will be affected equally. Race, geography, and economics play a role on the number of exposures to toxicants in the air and water and ability to mitigate the effects. 12 Rising temperatures and sea levels, extreme weather events, and increasing carbon dioxide levels will increase food, air, and water pollution. This will lead to more cardiovascular and respiratory conditions, heat related illnesses, vector born conditions such as malaria, Lyme disease and West Nile virus, more gastroenteritis from food borne pathogens, mycotoxin exposure, mental health effects and event climate refuges as people flee areas affected by wildfires, drought, and floods. 13
Exposures to these toxicants will impact children’s health through prenatal in-utero exposure. We know that toxicant exposures influence children’s health can begin before prenatally, reflecting parents’ diets and parent’s air, water, and food quality. 15 This can affect children’s cognitive and behavioral development, mental and physical health. Health impacts on children due increases in extreme weather events, temperatures and heat, and sea level rise that result from climate change may include acute injuries, chronic mental illness, food insecurity, food, and water contamination, and increases in cardiovascular, pulmonary, and endocrine health conditions. 15
Summary
Climate change will have a significant impact on the number of toxicants in our food, water, and air. These chemicals, even in low doses, are known to create adverse health effects disrupting the immune, neurological, and hormonal systems. Climate change is also having effects on health through more extreme weather events such as flooding, heat, droughts, changes in food and water borne pathogens, and even the supply of food and water. It is imperative that health care providers be aware of the links between toxicants and health conditions, understand the possible exposures from food, water, and air, know how to educate patients on proper avoidance technique. Health care providers trained in environmental medicine can offer toxicant testing through blood and urine and make treatment recommendation based on the results. Learn more in my book; 8 Weeks to Women’s Wellness, which includes information on toxicant exposure, the links to 10 women’s health conditions, avoidance recommendations and an 8 week detoxification plan to help support the body.
References
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