acute

Americans breathe unhealthy air

June 2, 2025 By EarthWise Leave a Comment

According to the American Lung Association’s annual State of the Air report, at least 156 million Americans – 46% of the population – live with unsafe levels of ozone, particulate pollution, or both.

The report analyzed ozone and particulate pollution levels between 2021 and 2023, during which the worst wildfire season on record took place in Canada. The report ranked pollution levels in counties and cities across the country on a grading scale from A to F. At least 156 million people live with air that got the poorest grade of F for at least one of three pollutants. At least 42 million people live in counties that failed all three pollutant standards measured.

While the report attempts to provide a complete picture of air quality around the country, about two-thirds of counties lack air quality monitoring for ozone or particulate pollution.

The wildfires in Canada are responsible for much of the increase in air pollution in the past several years. However, climate projections suggest that the conditions that fueled those fires are likely to become increasingly common.

Air quality standards in the United States have generally been improving since the Clean Air Act was enacted by Congress in 1970. Since that time, levels of key pollutants have dropped by nearly 80%. But millions of Americans are still breathing polluted air, leading to both acute and chronic health conditions.

Plans by the Trump administration to loosen environmental regulations and cut funding for air quality research are likely to only make matters worse.

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Almost Half of Americans Breathe Unhealthy Air, Report Finds

Photo, posted June 8, 2023, courtesy of Anthony Quintano via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megadroughts

February 24, 2025 By EarthWise Leave a Comment

A new study by Swiss and Austrian scientists has found that persistent multi-year droughts have become increasingly common since 1980 and will continue to proliferate as the climate warms.

There are multiple examples in recent years in places ranging from California to Mongolia to Australia. Fifteen years of persistent megadrought in Chile have nearly dried out the country’s water reserves and even affected Chile’s vital mining output. These multi-year droughts have triggered acute water crises in vulnerable regions around the world.

Droughts tend to only be noticed when they damage agriculture or visibly affect forests. An issue explored by the new study is whether megadroughts can be consistently identified and their impact on ecosystems understood.

The researchers analyzed global meteorological data and modeled droughts over a forty-year period beginning in 1980. They found that multi-year droughts have become longer, more frequent, and more extreme, covering more land. Every year since 1980, drought-stricken areas have spread by an additional fifty thousand square kilometers on average, an area the size of Vermont and New Hampshire combined.

The trend of intensifying megadroughts is clearly leading to drier and browner ecosystems. Tropical forests can offset the effects of drought as long as they have enough water reserves. However, the long-term effects on the planet and its ecosystems remain largely unknown. Ultimately, long-term extreme water shortages will result in trees in tropical and boreal regions dying, causing long-term and possibly irreversible damage to these ecosystems.

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The Megadroughts Are upon Us

Photo, posted January 7, 2018, courtesy of Kathleen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Car tires in your salad

June 26, 2024 By EarthWise Leave a Comment

There seems to be no end to the types of pollution we have introduced into the environment. One that has only recently started to gain attention is pollution caused by vehicle tires.

Through normal wear and tear, as vehicles drive along roadways, their tires cast off countless bits of rubber. These particles can linger in the atmosphere or can be washed down sewage drains and into waterways. In the water, these particles leach compounds that are toxic to wildlife.

Tires contain various chemical additives that prevent them from cracking and degrading along with various metals and other materials added to rubber and artificial rubber. Some of these additives are acutely toxic or even carcinogenic.

A recent study by researchers at the University of Vienna tested leafy vegetables that were grown in Switzerland, Spain, and Italy, and were sold in Swiss supermarkets. The study also tested vegetables harvested directly from Israeli farmlands.

Tire ingredients were found in 11 out of 15 samples gathered from Swiss supermarkets and 9 out of 13 samples collected from Israeli fields. Among these are 6PPD, a tire additive that has been identified as the cause of the extensive deaths of coho salmon on the US West Coast.

The researchers say that farmers may be introducing tire additives by irrigating crops with treated wastewater or by using sewage sludge as fertilizer. Airborne tire particles may also be settling on farm soil.

The concentration of tire particles found in the leafy vegetables are relatively low, but it is troubling that we are eating dangerous chemicals used to improve the quality of tires.

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Leafy Vegetables Found to Contain Tire Additives

Photo, posted October 14, 2014, courtesy of Green Mountain Girls Farm via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pollution From Tires | Earth Wise

October 16, 2023 By EarthWise Leave a Comment

A few years ago, researchers investigating massive deaths of coho salmon in West Coast streams discovered that the water contained particles from vehicle tires. The cause of the fish mortality turned out to be a chemical called 6PPD that is added to tires to prevent cracking and degradation. The mystery was solved, but so far, the chemical continues to be used by all major tire manufacturers and is found on roads and in waterways around the world.

Worse still, the acute toxicity of 6PPD and the chemicals that it transforms into when exposed to ground-level ozone is only the tip of the tire pollution iceberg. Tire rubber contains more than 400 chemicals and compounds, many of which are carcinogenic.

About 2 billion tires are sold across the globe each year and that number is expected to reach 3.4 billion by 2030. Tires are made from about 20% natural rubber and 24% synthetic rubber, which requires about 4 gallons of petroleum per tire. Hundreds of other ingredients – including steel, fillers, heavy metals like copper, cadmium, lead, and zinc – make up the rest.

Tire wear particles are emitted continually as vehicles travel. They range in size from visible pieces of rubber or plastic to microparticles. Research has shown that a car’s four tires collectively emit half a trillion ultrafine particles per mile driven. These particles are small enough to be breathed into the lungs and can travel throughout the body and even cross the blood-brain barrier. Particle pollution from tires exceeds that from tailpipes.

Tire pollution is a huge problem that is just starting to receive the attention it deserves.

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Road Hazard: Evidence Mounts on Toxic Pollution from Tires

Photo, posted June 22, 2018, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Giant Farming Robots | Earth Wise

April 20, 2023 By EarthWise Leave a Comment

Farmers are perpetually engaged in a battle against weeds, which can strangle crops and destroy their yields. There are basically two ways to fight weeds: spraying herbicides that are bad for the environment and human health or using human labor to pull the weeds by hand.

Both choices are increasingly undesirable. Herbicide resistance is a growing problem facing farms around the world and widespread labor shortages in the agricultural sector are making it increasingly difficult to use human resources to combat weeds.

A startup company called FarmWise founded by an MIT engineering alumnus is providing a third option for farmers. The company has developed giant autonomous weeding robots that use artificial intelligence to cut out weeds without damaging crops.

The company’s first product is called the Titan. It looks like a large tractor without a driver’s seat. It uses machine vision to distinguish weeds from crop plants like leafy greens, cauliflower, artichokes, and tomatoes. It snips off the weeds with sub-inch precision.

Fifteen titan robots have been roaming the fields of 30 large farms in California and Arizona for several years. A newer robot, called the Vulcan, is more lightweight and is pulled by a tractor. FarmWise continues to add new crops to its database so that the robots can be used to fight weeds in more and more kinds of farms.

Weed problems are especially acute for farmers of specialty crops, which grow on smaller farms than corn and soybeans, and have unique growing practices, which limit the effectiveness of chemical and technical solutions.

The overall goal of FarmWise is to turn artificial intelligence into a tool that is as reliable and dependable as GPS is now in the farming industry.

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Titanic robots make farming more sustainable

Photo, posted August 23, 2021, courtesy of Carol VanHook via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sea Level Rise And Global Security | Earth Wise

March 22, 2023 By EarthWise Leave a Comment

Recently, United Nations General Secretary Antonio Guterres addressed the U.N. Security Council on the issue of the security threats created by rising sea levels. In the past, some members of the Security Council – notably Brazil, China, Russia, and at times, India – have argued that the U.N.’s climate program should address such issues and that the Security Council doesn’t have a mandate or the expertise to consider the issue. The underlying problem is that by addressing the security issues created by rising seas, other sensitive geopolitical issues might come to the forefront.

Guterres’ speech focused on the real possibility that rising seas could disrupt and destabilize global societies unless there is an organized international effort to get ahead of the problem. Major cities facing serious impacts from rising seas include Cairo, Lagos, Bangkok, Jakarta, Mumbai, Shanghai, Copenhagen, London, Los Angeles, New York, and Buenos Aires, among others.

In all, Guterres said that the danger is most acute for about 900 million people living in low-lying coastal areas. Some countries, particularly small island developing countries, could disappear entirely.

The world is already facing refugee crises related to politics, warfare, and extreme weather. The flood of refugees created by rising seas could be biblical in magnitude.

The confluence of climate change and global security is growing steadily. As the global body primarily responsible for maintaining international peace and security, the U.N. Security Council cannot duck this issue much longer. It has a critical role to play in building the political will required to address the security challenges looming from rising seas.

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Sea Level Rise Could Drive 1 in 10 People from Their Homes, with Dangerous Implications for International Peace, UN Secretary General Warns

Photo, posted July 19, 2021, courtesy of Face of the World via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio