antibiotic resistance

Microplastics and antibiotic resistance

April 14, 2025 By EarthWise Leave a Comment

Microplastics are a real problem. They are pretty much everywhere. They are in our food, in the oceans, on mountains, up in the clouds, and most alarmingly, in our bodies. All of that is already bad news, but researchers at Boston University have found that microplastics may also be contributing to antibiotic resistance in dangerous bacteria.

The researchers observed that bacteria exposed to microplastics become resistant to multiple types of antibiotics commonly used to treat infections. Bacteria can become resistant to antibiotics for a number of reasons, including misuse and overprescribing of medications. However, a major factor influencing antibiotic resistance is the microenvironment – the immediate surroundings of a microbe – which is where bacteria and viruses replicate.

The Boston University study tested how the common bacterium E. coli reacted to being in a closed environment with microplastics. The plastics provide a surface that the bacteria can attach to and colonize. When attached to a surface, bacteria create a sticky substance called a biofilm that acts like a shield, protecting the bacteria and keeping them affixed securely. The tests showed that microplastics supercharged the biofilms so much that when antibiotics were introduced, they were unable to penetrate the shield.

Microplastics are everywhere, but they are especially prevalent in impoverished places where sanitation may be limited. Refugees, asylum seekers, and forcibly displaced populations are already at increased risk of contracting drug-resistant infections. The prevalence of microplastics adds another risk to the already difficult lives of these people.

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Microplastics Could Be Fueling Antibiotic Resistance, BU Study Finds

Photo, posted May 15, 2021, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Antibiotics In Animal Agriculture | Earth Wise

April 13, 2023 By EarthWise Leave a Comment

In animal agriculture, farmers use antibiotics to treat, prevent, and control animal diseases, and to increase the productivity of their operations. According to the FDA, approximately 80% of all antibiotics sold in the U.S. are purchased for use in food-producing animals.

The routine administration of antibiotics to farm animals for non-therapeutic purposes promotes the development of antibiotic-resistant bacteria, with repercussions for human and animal health. As antibiotic-resistant bacteria spreads, medicines used to treat human diseases can become less effective.

According to a new study led by researchers from the University of Washington, a California policy restricting the use of antibiotics in farm animals is associated with a reduction in one type of antibiotic-resistant infection in people in the state. The findings, recently published in the journal Environmental Health Perspectives, suggest that regulations limiting the use of antibiotics in livestock can significantly impact human health.

In 2018, California Senate Bill 27 banned routine preventive use of antibiotics in food-animal production and any antibiotic use without a veterinarian’s prescription. Last year, the European Union passed a law restricting antibiotic use to only sick animals on farms. And coming this June, most antibiotics – those that are medically important to humans and animals – will be by prescription only in the United States.

Despite these changes, antibiotic resistance is projected to remain one of the biggest threats to human health over the next 50 years because resistance continues to grow and few new antibiotics are coming online.

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Restricting antibiotics for livestock could limit spread of antibiotic-resistant infections in people

Ranchers should prepare now for 2023 animal antibiotic guidelines

Photo, posted May 8, 2018, courtesy of Preston Keres / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Dangers Of Thawing Permafrost | Earth Wise

April 12, 2022 By EarthWise Leave a Comment

The thawing of the permafrost in the Arctic is a major concern from the standpoint of the potential release of enormous amounts of carbon dioxide trapped in it. There are nearly 2,000 billion tons of carbon there, which is as much as humanity releases into the atmosphere in 50 years. But greenhouse gases are not the only danger posed by permafrost thawing. There are also microbes, unknown viruses, and chemicals that could be very dangerous.

More than 100 diverse microorganisms in Siberia’s deep permafrost have been found to be antibiotic resistant. The deep permafrost is one of the few environments on Earth that have not been exposed to modern antibiotics. As the permafrost thaws, its bacteria could mix with meltwater and create new antibiotic-resistant strains.

By-products of fossil fuels – introduced into permafrost environments since the beginning of the industrial revolution – are present. Metal deposits including arsenic, mercury, and nickel, have been mined for decades and have contaminated large areas.

Now-banned pollutants and chemicals – including DDT – came to the Arctic through the atmosphere and over time have become trapped in the permafrost.

There is now ongoing research further characterizing the microbes frozen in permafrost and providing more precise measurement of emissions hotspots in permafrost regions. Scientists are increasingly turning to integrated Earth observations from the ground, the air, and space.

There are models that predict the gradual release of emissions from permafrost over the next century. Other models say it could happen within just a few years. The worst-case scenario would be utterly catastrophic but none of the scenarios portend anything good.

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Thawing Permafrost Could Leach Microbes, Chemicals Into Environment

Photo, posted February 9, 2017, courtesy of Benjamin Jones/USGS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Could Lyme Disease Be Eradicated? | Earth Wise

November 22, 2021 By EarthWise Leave a Comment

Tiny ticks are a big problem. Measuring only three to five millimeters in size, ticks are widely distributed around the world. They are external parasites, feasting on the blood of birds, reptiles, amphibians, and mammals – including humans.

According to estimates from the Centers for Disease Control and Prevention, ticks infect an estimated 476,000 people with Lyme disease in the United States every year. Lyme disease is caused by a bacterium called Borrelia burgdorferi that lurks in wild mice. Ticks that feed on the mice become infected and can then in turn infect people and animals.

The disease is not only a problem in the United States, but in other parts of North America, Europe and Asia as well. It often causes a characteristic “bullseye” rash and flu-like symptoms. If left untreated, it can lead to serious long-term health problems.

Currently, lyme disease is treated using antibiotics. But antibiotics kill a wide range of bacteria – including healthy gut bacteria – which can lead to additional health issues and more antibiotic resistance.

A recent discovery by researchers from Northeastern University in Boston could allow Lyme disease to be eradicated in the wild. The researchers found that a compound called hygromycin A is deadly to the bacterium that causes Lyme disease but harmless to animals and has little effect on most other bacteria.

The little-known antibiotic cleared Lyme disease infection in mice, both when administered via injection and when ingested using bait. As a result, dropping feeding baits could eradicate Lyme disease from whole areas or even entire countries. The first field trial will be next summer.

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Drug treatment for Lyme disease could lead to its eradication

Photo, posted June 21, 2017, courtesy of NIAID via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.