Cloudy with a chance of toxics: How climate change is increasing our vulnerability to chemical pollution
"Cloudy with a chance of toxics: How climate change is increasing our vulnerability to chemical pollution"
This guest post is by Elizabeth Grossman, author of Chasing Molecules: Poisonous Products, Human Health, and the Promise of Green Chemistry and High Tech Trash: Digital Devices, Hidden Toxics, and Human Health, and other books. She writes about environmental and science issues for the Washington Post, Salon, Mother Jones, the Nation, Grist, and other publications from Portland, Oregon. One of the book’s jacket quotes is from The great environmental writer and founder of 350.org, Bill McKibben: “There are enough environmental problems that seem insoluble. Elizabeth Grossman has given us this chronicle of a field with a bright future, the green chemistry that will replace the crude methods of the 19th century with the smart ones of the 21st. She tells us how it could happen. We should listen carefully!“
To melting ice caps, rising sea levels, acidifying oceans, and storm surges, add lung diseases and kidney stones to the expected effects of climate change. At a November 19 briefing in Washington, researchers from the Harvard Center for Health and the Global Environment, representatives of the American Medical Association and American Public Health Association detailed the likely negative health effects of global warming. These are conditions, reported Paul Epstein, Associate Director of the Harvard center, to which children, the elderly, and poor are especially vulnerable.
Rising temperatures, ozone and sulfur dioxide levels, along with particulate and other pollutants released by forest fires, will create conditions that are expected to increase rates of hospitalization for respiratory diseases, among them pneumonia, asthma, and chronic lung disease. Increased heat exposure, noted the researchers who’ve described these effects in a letter to President Obama, is also likely to increase the incidence of kidney stones.
But these are just some of the adverse health impacts associated with climate change.
In addition to the effects noted at the November 19 briefing – and those prompted by impacts of drought and altered insect patterns – rising temperatures are already triggering environmental conditions that have less visible but potentially profound health implications.
For traveling with global air and ocean currents are a soup of environmentally persistent synthetic chemicals whose behavior and effects are being exacerbated by climate change. Scientists tracking these chemicals around the globe are discovering that the movement of these long-lasting substances – manufactured materials that have no natural origin – is being accelerated by effects of rising temperatures. Researchers are also finding that global warming is increasing human and wildlife communities’ vulnerability to these chemicals’ biological impacts.
One of the places this is happening most dramatically is in the Arctic. Thanks to patterns of atmospheric circulation, whatever is released into air and oceans in the Northern Hemisphere, eventually moves north. This includes persistent pollutants.
After drifting north over months, years – and even decades – these chemicals typically become lodged in ice, snow, and permafrost. But as temperatures rise, these contaminants are being released as glaciers, polar sea ice, and permafrost melt. At the same time, climate change is prompting earlier Arctic springs, longer summers, and increased precipitation. More rain and snow and greater and faster snowmelt are causing erosion along polar riverbanks, lakes, and coastlines. Consequently, soil-bound contaminants are being washed into nearby water along with whatever pollutants arrive with the precipitation itself.
Further south, extreme storms like Hurricane Katrina can similarly release contaminants previously held in place by soil and send them into adjacent air and water. Some of these chemicals will later move into the atmosphere and back down to Earth again with moisture. Raining toxics sounds a bit extreme, but that’s what it amounts to.
What makes these chemicals’ behavior of even greater concern is that they are finding their way into our food, our bodies, and the innermost workings of living cells.
This is happening because many of these persistent synthetic chemicals are fat-soluble. In the Arctic – and in more temperate latitudes – these chemicals are accumulating in fat cells and thus climbing the food web. Arctic animals, particularly top predators like polar bears, with their large fat stores have among the highest levels recorded of some of these mobile persistent pollutants.
Meanwhile, seasonal climate changes are adding to these animals’ vulnerability. As altered temperature patterns change timing and location of food sources, some animals in polar regions north and south must migrate farther to find food. The lengthened hunting trips increase the animals’ stress levels and their reliance on stored body fat. Because fat cells serve as a reservoir for many contaminants, when fat is broken for energy, the toxics are also released, exposing the animals from within. There is concern that such toxics release is happening in people as well – concern underscored by the fact that a number of these chemicals appear to disrupt hormone activity with results that include adverse impacts on metabolism, including fat production.
There is no quick fix for these problems but it is worth noting that our reliance on fossil fuels has helped make petrochemicals the foundation for the overwhelming majority of our synthetic materials – manufactured substances that go into everything from computers to cosmetics. And petrochemicals have particularly problematic environmental and health impacts. To begin stem this tide, as we begin to shift away from fossil fuels and create new materials – alternatives to those with adverse environmental and health impacts – among the questions we must ask to help ensure new materials’ safety must be: how a substance behaves biologically – its impact on living cells – and how it behaves physically, including its possible contribution to the impacts of climate change.