Alligators exposed to ‘forever chemicals’ show autoimmune impacts: study

Read the full story in The Hill.

Alligators exposed to “forever chemicals” in North Carolina’s Cape Fear River may be experiencing adverse clinical and autoimmune effects, a new study has found. 

In addition to showing genetic indicators for immune system impacts, the animals had many unhealed or infected lesions, according to the study, published on Thursday in Frontiers in Toxicology. 

Algorithm formulated to assess environmental risk of personal care products

Read the full story at Cosmetics & Toiletries.

A recent article published in Toxicological Research examines the potential impact of shampoo, conditioner, facial cleansers, etc., on the environment after they are used and the remaining chemicals spiral down the drain. This work responds to concerns by regulators and consumer groups, among others, over the potential for such rinse-off personal care products to be detrimental to ecosystems, most predominantly aquatic life.

Conserving critical habitat in the face of climate change in Midwestern lakes by managing watershed land use

Read the full story from the University of Minnesota.

Lakes across the Midwest are losing cold, oxygenated habitat as a result of climate change and nutrient pollution. This loss of critical habitat has negative consequences for water quality, fish, and the production of greenhouse gases. While data show that effectively managing watershed land use at a local scale can protect coldwater, oxygen-rich habitats and reduce nutrient pollution in Midwestern lakes, lake-specific targets for watershed management are lacking. 

In a University of Minnesota study published in Ecosphere, researchers used statistical models to estimate the resilience of over 10,000 lakes in the upper Midwest to both climate change and land use in order to identify temperature and watershed conditions above which critical habitat was lost. For lakes in which watershed land use was predicted to influence coldwater habitat, the researchers identified lake-specific thresholds for protecting or restoring forested watersheds. They also estimated the uncertainty in how individual lakes would respond to both climate and land use change.

Sulfoxaflor poses risks to endangered species, US EPA finds

Read the full story in Chemical & Engineering News.

The insecticide sulfoxaflor, which is less toxic than organophosphates and neonicotinoids, is likely to harm about one-third of species listed as endangered or threatened in the US, according to a draft biological evaluation released July 19 by the Environmental Protection Agency. The agency predicts that mitigation measures will protect most of those species, however.

Do chemicals in sunscreens threaten aquatic life? A new report says a thorough assessment is ‘urgently needed,’ while also calling sunscreens essential protection against skin cancer

Sunscreens for sale at a Walgreens drug store. Jeff Greenberg/Universal Images Group via Getty Images

by Robert Richmond, University of Hawaii and Karen Glanz, University of Pennsylvania

Studies have shown that the same active ingredients in sunscreens that protect people from cancer-causing ultraviolet rays can be toxic to a range of species in oceans, rivers and lakes. With both of these risks in mind, a new report from the National Academies of Sciences, Engineering and Medicine finds an urgent need for more information about whether these chemicals threaten aquatic life on a broad scale.

The report calls on the U.S. Environmental Protection Agency to conduct a detailed review called an environmental risk assessment of the likelihood that exposure to one or more of these chemicals, called UV filters, may harm organisms in saltwater and freshwater ecosystems. The study recommends focusing on two types of settings – coral reefs in shallow waters near shore, and slow-moving freshwater bodies like ponds and marshes – that are heavily used for recreation and/or exposed to wastewater or urban runoff.

The study recognizes that sunscreen with a Sun Protection Factor (SPF) of 30 or higher is an effective defense against sunburn and skin cancer, and that making it harder to buy broad-spectrum sunscreen that people will actually use could harm public health. Accordingly, it calls for research examining how changes in sunscreen usage could affect human health. Two members of the study committee explain how their group balanced these concerns.

Many species are exposed to many stresses

Robert Richmond, Research Professor and Director, Kewalo Marine Laboratory, University of Hawaii at Manoa

Studies to date have provided compelling laboratory evidence that some UV filters can have toxic effects on aquatic species, including corals, anemones and zebrafish, that are exposed to the chemicals. These findings have raised concerns about sunscreens’ larger-scale impacts on biological communities and ecosystems.

But outcomes in the environment will differ depending on what compounds, ecosystems and local environmental conditions are involved. That’s especially true for coral reefs. The committee highlighted reefs because they are ecologically, economically and culturally valuable, and attract large numbers of tourists who use sunscreens.

Coral reefs are declining worldwide due to multiple human-induced disturbances. Some of these disturbances are global, such as ocean warming and acidification driven by climate change. Other stressors, such as coastal water quality, are more local.

Studying the effects of chemicals on corals and coral reefs is challenging because they are both complex systems. Reef-building corals are a combination of an animal, single-celled algae and rich populations of bacteria living and working together. Coral reefs are made up of thousands of interacting organisms.

Importantly, many stress responses in corals occur without causing outright death, but impair their health, growth, resilience and even ability to reproduce. Scientists need to know more about these responses to guide effective management responses and interventions.

Dozens of parrotfish swim over a reef of res, white and yellow corals.
Healthy coral reefs like this one in American Samoa support such diverse communities of fish and other organisms that they often are called the rainforests of the sea. Kevin Lino, NOAA/Flickr, CC BY

After in-depth reviews of the existing data, our study committee recommended that the U.S. Environmental Protection Agency should undertake an ecological risk assessment of the 17 UV filters used in sunscreens sold in the U.S. Such a study would include a comparison of toxicity findings to relevant concentrations and exposure conditions.

For example, what happens to organisms exposed to these chemicals occasionally versus those exposed regularly, in calm bays or along open, wave-swept coasts? How do UV filters differ in whether they break down in water, or accumulate in sediments or the tissues of living organisms?

In our view, an ecological risk assessment would provide EPA and others the basis for sound and effective policy development. The sooner this happens and the results are applied to the regulatory process, the better for everyone who is affected, including future generations.

Lab results versus real-world conditions

Karen Glanz, George A. Weiss University Professor and Director, UPenn Prevention Research Center, University of Pennsylvania

The question of whether UV filters pose harm to the environment while helping to reduce skin damage and prevent skin cancer is a conundrum. It seemingly pits human and environmental health against each other head-to-head and asks policymakers, medical experts and the public to choose between them.

Humans need sunlight to live, but overexposure to the sun’s damaging rays – ultraviolet radiation – causes sunburn and wrinkles and is a risk factor for the development of skin cancers, including the most deadly type, melanoma. Routine use of broad-spectrum sunscreen with SPF 30+ when outdoors has been found to prevent skin damage and skin cancer. But sunscreens are most effective as part of a set of behaviors that also includes wearing hats and cover-up clothing and seeking shade.

Most people in the U.S. don’t practice these behaviors frequently or thoroughly enough. So it’s important to weigh very carefully the potential effects of restricting the choice of available sunscreens.

Some jurisdictions already restrict the sale of certain sunscreens because concerned advocates believe doing so will be good for the environment. In the U.S., they include Hawaii, the U.S Virgin Islands and the city of Key West, Florida. Our report doesn’t draw a definitive conclusion about whether these measures are scientifically justified or effective. Rather, it emphasizes analyzing whether and how they may affect human health as well as the environment.

The study draws attention to the challenge of understanding risks from UV filters to aquatic environments under various conditions, and in the context of overarching environmental stressors such as rising sea temperatures. It’s important to understand that for both environmental and human health issues, laboratory studies don’t always match what happens in the environment.

Studies of model systems such as bacteria and yeast, and organisms such as fish embryos and insect larvae, can yield findings that do not hold up in studies of humans. For both the environment and humans, it may not be possible or ethical to conduct true experiments that test the long-term effects of chemicals in UV filters.

Members of our committee wrestled to interpret the available evidence, and also with the gaps in that evidence. Ultimately we concluded that the science is not settled, but that there is much to build on to advance understanding of this issue. Our conclusions are not a win/lose outcome for either the environment or humans. Rather, they point to a need to think both broadly and strategically for the benefit of people and the planet.

Robert Richmond, Professor of Biology and Director, Kewalo Marine Laboratory, University of Hawaii and Karen Glanz, George A. Weiss University Professor and Director, UPenn Prevention Research Center, University of Pennsylvania

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Opinion: On the Hudson River, a new model of environmental stewardship

Read the full story at Undark.

The languishing waterway offers an indispensable lesson for scientists: Environmental problems are human problems.

Disease-causing parasites can hitch a ride on plastics and potentially spread through the sea, new research suggests

The sticky biofilms that form on microplastics can harbor disease-causing pathogens and help them spread. Tunatura/iStock via Getty Images Plus

by Karen Shapiro, University of California, Davis and Emma Zhang, University of California, Davis

Typically when people hear about plastic pollution, they might envision seabirds with bellies full of trash or sea turtles with plastic straws in their noses. However, plastic pollution poses another threat that’s invisible to the eye and has important consequences for both human and animal health.

Microplastics, tiny plastic particles present in many cosmetics, can form when larger materials, such as clothing or fishing nets, break down in water. Microplastics are now widespread in the ocean and have been found in fish and shellfish, including those that people eat.

As researchers studying how waterborne pathogens spread, we wanted to better understand what happens when microplastics and disease-causing pathogens end up in the same body of water. In our recent study published in the journal Scientific Reports, we found that pathogens from land can hitch a ride to the beach on microscopic pieces of plastic, providing a new way for germs to concentrate along coastlines and travel to the deep sea.

Aerial shot of boat floating through plastic pollution on water
Microplastic pollution has negative consequences for human, animal and environmental health. Yunaidi Joepoet/Moment via Getty Images

Investigating how plastics and pathogens interact

We focused on three parasites that are common contaminants in marine water and seafoods: the single-celled protozoans Toxoplasma gondii (Toxo), Cryptosporidium (Crypto) and Giardia. These parasites end up in waterways when feces from infected animals, and sometimes people, contaminate the environment.

Crypto and Giardia cause gastrointestinal disease that can be deadly in young children and immunocompromised individuals. Toxo can cause lifelong infections in people, and can prove fatal for those with weak immune systems. Infection in pregnant women can also cause miscarriage or blindness and neurological disease in the baby. Toxo also infects a wide range of marine wildlife and kills endangered species, including southern sea otters, Hector’s dolphins and Hawaiian monk seals.

To test whether these parasites can stick onto plastic surfaces, we first placed microplastic beads and fibers in beakers of seawater in our lab for two weeks. This step was important to induce the formation of a biofilm – a sticky layer of bacteria and gellike substances that coats plastics when they enter fresh or marine waters. Researchers also call this sticky layer an eco-corona. We then added the parasites to the test bottles and counted how many became stuck on the microplastics or remained freely floating in the seawater over a seven-day period.

Biofilms are vast communities of microbes that can form on almost any surface, including your teeth.

We found that significant numbers of parasites were clinging to the microplastic, and these numbers were increasing over time. So many parasites were binding to the sticky biofilms that, gram for gram, plastic had two to three times more parasites than did seawater.

Surprisingly, we found that microfibers (commonly from clothes and fishing nets) harbored a greater number of parasites than did microbeads (commonly found in cosmetics). This result is important, because microfibers are the most common type of microplastic found in marine waters, on coastal beaches and even in seafood.

Plastics could change ocean disease transmission

Unlike other pathogens that are commonly found in seawater, the pathogens we focused on are derived from terrestrial animal and human hosts. Their presence in marine environments is entirely due to fecal waste contamination that ends up in the sea. Our study shows that microplastics could also serve as transport systems for these parasites.

These pathogens cannot replicate in the sea. Hitching a ride on plastics into marine environments, however, could fundamentally alter how these pathogens move around in marine waters. We believe that microplastics that float along the surface could potentially travel long distances, spreading pathogens far from their original sources on land and bringing them to regions they would not otherwise be able to reach.

On the other hand, plastics that sink will concentrate pathogens on the sea bottom, where filter-feeding animals like clams, mussels, oysters, abalone and other shellfish live. A sticky biofilm layer can camouflage synthetic plastics in seawater, and animals that typically eat dead organic material may unintentionally ingest them. Future experiments will test whether live oysters placed in tanks with and without plastics end up ingesting more pathogens.

Diagram illustrating how pathogens can associate with biofilms on microplastics and spread through the sea.
The biofilms that form on microplastics can help pathogens spread through the sea. Emma Zhang, CC BY-NC-ND

A One Health problem

One Health is an approach to research, policy and veterinary and human medicine that emphasizes the close connection of animal, human and environmental health. While it may seem that plastic pollution affects only animals in the ocean, it can ultimately have consequences on human health.

Our project was conducted by a multidisciplinary team of experts, ranging from microplastics researchers and parasitologists to shellfish biologists and epidemiologists. This study highlights the importance of collaboration across human, animal and environmental disciplines to address a challenging problem affecting our shared marine environment.

Our hope is that better understanding how microplastics can move disease-causing pathogens in new ways will encourage others to think twice before reaching for that plastic straw or polyester T-shirt.

Karen Shapiro, Associate Professor of Pathology, Microbiology and Immunology, University of California, Davis and Emma Zhang, Veterinary researcher, University of California, Davis

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Microplastics and pollution combine to become much more toxic: Study

Read the full story in Environmental Health News.

Microplastics can pick up pollution in their travels and pose an even greater threat to human health, according to a new study.

In the ocean, for example, toxic compounds can hitch a ride on plastic and make the material 10 times more toxic than it would normally be, according to the research published earlier this year in Chemosphere.

Although the dangers of both microplastics and harmful compounds have been studied individually, few researchers have look at their combined effect. This study is also unique in that the researchers tested these polluted plastic particles on human cells—most previous research has focused on the impacts on marine life.

New scoring scale tracks the harmful effects of salt pollution in freshwater streams and rivers

Read the full story from the University of Maryland.

A new study sheds light on how salinization from winter road salt combined with other pollutants creates ‘chemical cocktails’ that can jeopardize the ecological balance of waterways, including those in the Washington, D.C. area. The researchers developed a new five-stage scale (Stage 0-IV) to track the progression of this damage, a tool that could inform public policy in the future. Parts of the Potomac, the Anacostia and Rock Creek waterways are in Stage III on the scale for at least part of the year.

Birds of prey populations across Europe suppressed by lead poisoning from gun ammunition

Read the full story from the University of Cambridge.

Poisoning caused by preying on or scavenging animals shot by hunters using lead ammunition has left the populations of many raptors – or birds of prey – far smaller than they should be, according to the first study to calculate these impacts across Europe.