2025 Environmental Health Risks

• Chagas kills more people in Latin America each year than malaria

• Roughly 300,000 people in the U.S. are infected, many without knowing it

• Cases have been confirmed in 30 states, including California

It’s one of the most insidious diseases you’ve probably never heard of. Chagas disease, caused by the parasite Trypanosoma cruzi, is spreading across California and at least 29 other states. Researchers estimate that as many as 300,000 people in the U.S. may already be infected — most of them unaware until it strikes years later with heart failure, stroke or sudden death.

The kissing bug connection

The parasite lives in a bloodsucking insect called the kissing bug. About a dozen species are found in the U.S. Research in Los Angeles’ Griffith Park shows that nearly a third of local kissing bugs carry the parasite. Wildlife including wood rats, skunks, mice, raccoons and even black bears have also tested positive, making the reservoir for infection wide and varied.

“Kissing bugs are pretty equal opportunity when it comes to who they take a blood meal from,” said Sarah Hamer, an epidemiologist at Texas A&M University in a Los Angeles Times report. 

From rural stigma to urban reality

Historically regarded as a disease of rural Latin America, Chagas is increasingly appearing in U.S. patients with no foreign travel history. Doctors report infections in unexpected places, including an affluent Hollywood Hills neighborhood. California has the highest number of known cases — between 70,000 and 100,000 — both from immigrants arriving with the disease and from possible local transmission.

From 2019 to 2023, Los Angeles County alone confirmed about 180 cases. Health experts warn those numbers likely represent only a fraction of infections, since Chagas is not a reportable disease in most of California.

A neglected disease with deadly consequences

The lack of routine screening means many patients go undiagnosed until irreversible damage occurs. “If we screened for it and caught it early, most patients could be cured,” said Kaiser Permanente cardiologist Salvador Hernandez. “The problem is we don’t, and people end up dying or requiring terrifically expensive care.”

Antiparasitic drugs can stop the parasite if given in time. Dogs are also vulnerable, often becoming infected by eating the bugs.

Calls for recognition and action

Epidemiologists and medical experts are pressing the Centers for Disease Control and Prevention and the World Health Organization to declare Chagas endemic in the U.S. Such a move could bring wider awareness, research funding and public health investment.

“This is a disease that has been neglected and has been impacting Latin Americans for many decades,” said Norman Beatty, a University of Florida medical epidemiologist. “But it’s also here in the United States.”

Here’s a sidebar draft you could run alongside the main story:

How to spot Chagas symptoms

Chagas disease can remain silent for years, but when symptoms do appear, they often mimic other illnesses. Doctors say early recognition is key.

Early or acute symptoms (days to weeks after infection):

• Swollen eyelid or face (sometimes called Romaña’s sign)

• Fever, fatigue, rash

• Swollen lymph nodes

• Nausea, diarrhea or loss of appetite

Chronic symptoms (years later, often mistaken for other conditions):

• Irregular heartbeat or palpitations

• Enlarged heart, heart failure or sudden cardiac arrest

• Stroke or seizures

• Difficulty swallowing or severe constipation from digestive tract damage

Why it’s missed:

• Many patients have no symptoms until advanced disease develops

• Signs often resemble more common cardiac or gastrointestinal problems

• Most U.S. physicians do not routinely screen for it

What helps:

• Blood donation centers sometimes detect infections during screening

• Antiparasitic medications can stop disease progression if caught early

• Regular check-ups and heart health evaluations are critical for those at risk

• Study finds PFAS treatment also cuts other toxic contaminants

• Reductions seen in cancer-linked byproducts, nitrates and heavy metals

• Smaller, rural communities lag behind in access to advanced systems

Water treatment systems designed to remove the toxic “forever chemicals” known as PFAS may provide far greater public health benefits than previously recognized, according to new research from the Environmental Working Group (EWG).

A peer-reviewed study published in ACS ES&T Water shows that technologies like granular activated carbon, ion exchange and reverse osmosis not only reduce PFAS levels but also cut other hazardous contaminants from drinking water, including cancer-causing disinfection byproducts (DBPs), agricultural nitrates and heavy metals such as arsenic and uranium.

“PFAS treatment isn’t just about ‘forever chemicals,’” said Sydney Evans, EWG senior science analyst and lead author of the study. “It’s also opening the door to improving water treatment across the board.”

A potential game-changer

The study analyzed data from 19 U.S. utilities and the Environmental Protection Agency’s national monitoring program. Researchers found that installing advanced PFAS treatment led to a 42% drop in trihalomethanes and a 50% reduction in haloacetic acids, both carcinogenic byproducts of water disinfection.

“These kinds of reductions caused by PFAS filters are a game changer for public health, especially since where there are PFAS, there are always other chemicals, too,” said EWG analyst Varun Subramaniam.

Environmental injustice

Despite the health benefits, access to advanced filtration remains uneven. Only 7% of very small water systems, serving fewer than 500 people, use the technology, compared with 28% of the largest utilities.

“This is a textbook case of environmental injustice,” Subramaniam said. “The communities least able to afford advanced filtration often face the highest health risks.”

EWG researchers urged policymakers to address inequities by boosting federal and state funding for small, under-resourced water systems.

Regulatory setbacks

The findings come amid controversy over the Environmental Protection Agency’s recent moves to weaken limits on PFAS in drinking water and delay compliance deadlines, less than a year after new standards were finalized. Critics say the rollbacks could prolong harmful exposures, particularly in communities without access to advanced treatment.

“This study exposes a dangerous blind spot in federal water policy,” said Melanie Benesh, EWG’s vice president of government affairs. “Communities wouldn’t just filter out PFAS, they’d be eliminating multiple toxic chemicals at the same time.”

EWG also flagged gaps in national monitoring, arguing that inconsistent reporting prevents regulators from tracking co-occurring contaminants and evaluating treatment effectiveness.

Health risks of PFAS exposure

PFAS are known as “forever chemicals” because they do not break down in the environment and can accumulate in the body. The Centers for Disease Control and Prevention has detected PFAS in the blood of 99% of Americans, including newborns.

Exposure has been linked to suppressed immune function, reduced vaccine effectiveness, cancer risks and developmental harms.

“Advanced PFAS water treatment is a turning point,” Evans said. “When we fix one problem, we can solve several others. The opportunity to protect public health at scale is too big to ignore.”

• Blood levels of PFAS (“forever chemicals”) were linked to about a 31 % increased future risk of type 2 diabetes.
  

• The study compared 180 newly diagnosed diabetes cases with 180 matched non‑diabetic controls from Mount Sinai’s BioMe cohort.
  

• Metabolic disruptions in amino-acid and drug-processing pathways may offer clues to how PFAS interfere with blood sugar regulation.
  

Per‑ and polyfluoroalkyl substances (PFAS), or “forever chemicals,” have gotten a lot of attention recently for the plethora of health risks associated with them. 

Now, a new study from Mount Sinai suggests that PFAS exposure may quietly raise your risk of developing type 2 diabetes.

“PFAS are synthetic chemicals that resist heat, oil, water, and stains, and are found in countless everyday consumer products,” researcher Vishal Midya, Ph.D., M.Stat., said in a news release. 

“Because they don’t break down easily, PFAS accumulate in the environment — and in human bodies. Our study is one of the first to examine how these chemicals may disrupt the body’s metabolism in ways that increase diabetes risk — particularly in diverse U.S. populations.” 

The study

The research team conducted the study using BioMe, a health‑record linked biobank that has enrolled over 70,000 people at Mount Sinai Hospital since 2007. 

They selected 180 individuals recently diagnosed with type 2 diabetes and matched them with 180 similar participants (same age, sex, ancestry) who did not have diabetes. 

Blood samples from all participants were tested for PFAS levels. The researchers then examined how increasing PFAS exposure related to subsequent diabetes risk, while also exploring metabolic signatures in pathways tied to amino‑acid biosynthesis and drug metabolism.

The results

The key finding: For each step up in PFAS exposure (e.g. from low to moderate, moderate to high), there was a 31 % higher risk of developing type 2 diabetes later on. 

While the study can’t prove PFAS causes diabetes directly, it did find signs that PFAS may disrupt critical metabolic processes — specifically amino‑acid biosynthesis and drug metabolism — which are intimately involved in regulating blood sugar.

“This research leverages an exposomics framework to characterize environmental impacts and associated metabolic alterations contributing to the development of type 2 diabetes in vulnerable U.S. populations,” researcher Damaskini Valvi, M.D., Ph.D., MPH, said in the news release. 

“These findings can help us design more effective interventions for the early prevention of type 2 diabetes in the future, taking into account individuals’ exposures to environmental chemicals along with other well-known genetic, clinical, and lifestyle factors implicated in diabetes development. Mounting research suggests that PFAS are a risk factor for several chronic diseases, such as obesity, liver disease, and diabetes.” 

• Trained dogs were able to detect Parkinson’s disease from skin swabs with up to 80% accuracy.
  

• This method could lead to a faster, non-invasive way to diagnose the disease earlier.
  

• Researchers hope it could eventually help spot Parkinson’s years before symptoms appear.
  

What if a dog’s nose could help doctors diagnose Parkinson’s Disease (PD)? 

That’s exactly what new research from Medical Detection Dogs and the Universities of Bristol and Manchester has explored. 

In a recent study, two specially trained dogs were able to sniff out Parkinson’s with high accuracy, using nothing more than skin swabs from participants.

While we often associate medical detection dogs with things like cancer or diabetes, this study brings us one step closer to using man’s best friend as a tool in identifying neurological diseases — especially those like Parkinson’s that are notoriously hard to catch early.

“We are extremely proud to say that once again, dogs can very accurately detect disease,” Medical Detection Dogs CEO and Chief Scientific Officer Claire Guest said in a news release. 

“There is currently no early test for Parkinson’s disease and symptoms may start up to 20 years before they become visible and persistent, leading to a confirmed diagnosis. Timely diagnosis is key as subsequent treatment could slow down the progression of the disease and reduce the intensity of symptoms.”

The study

The star dogs — Bumper the Golden Retriever and Peanut the Labrador — were trained over several weeks using more than 200 skin swab samples. 

The samples came from two groups: people with Parkinson’s disease and those without. During training, the dogs learned to pick out the scent associated with Parkinson’s and were rewarded when they correctly identified positive samples — or correctly ignored the ones that didn’t show signs of the disease.

For the actual testing phase, researchers used a “double-blind” method. That means even the handlers didn’t know which samples were which — only a computer did. 

Each row of samples was presented in different orders, and any samples the dogs didn’t respond to were reshuffled and re-presented until a decision was made for every single one.

The results

The dogs showed up to 80% sensitivity (correctly identifying positive cases) and up to 98% specificity (correctly ignoring negative ones). 

Even more noteworthy? The dogs were still able to detect Parkinson’s even when patients had other unrelated health conditions, suggesting the scent they were picking up on is very specific to the disease.

There’s still no definitive test for Parkinson’s, and symptoms can take years — even decades — to fully show up. That’s why early detection tools like this have so much promise. 

“Identifying diagnostic biomarkers of PD, particularly those that may predict development or help diagnose disease earlier, is the subject of much ongoing research,” researcher Nicola Rooney said in the news release. 

“The dogs in this study achieved high sensitivity and specificity and showed there is an olfactory signature distinct to patients with the disease. Sensitivity levels of 70% and 80% are well above chance, and I believe that dogs could help us to develop a quick non-invasive and cost-effective method to identify patients with Parkinson’s disease.”

• EWG study shows tackling several tap water contaminants at once offers far greater health benefits than treating pollutants individually.

• Arsenic and chromium-6 frequently occur together and can be reduced using the same technologies.

• Small and rural communities face the highest risks and costs, underscoring a call for updated federal regulations.

A new study suggests that changing how America treats contaminated drinking water could save tens of thousands of lives. Instead of tackling one pollutant at a time, water systems should adopt multi-contaminant treatment strategies that can significantly reduce cancer risks nationwide, according to research published by the Environmental Working Group (EWG) in the journal Environmental Research.

The peer-reviewed study analyzed more than a decade’s worth of data from over 17,000 community water systems. EWG scientists found that simultaneously targeting dangerous chemicals like arsenic and hexavalent chromium, also known as chromium-6, could prevent more than 50,000 lifetime cancer cases in the U.S. Chromium-6 alone has been detected in water supplies serving about 251 million Americans.

“Drinking water is contaminated mostly in mixtures, but our regulatory system still acts like they appear one at a time,” said Tasha Stoiber, Ph.D., EWG senior scientist and lead author of the study. “This research shows that treating multiple contaminants together could prevent tens of thousands of cancer cases.”

Higher risk where pollution overlaps

Arsenic and chromium-6 frequently co-occur in drinking water systems and can be removed using similar technologies like reverse osmosis and ion exchange. The study found that reducing arsenic levels by as little as 27% to 42% in systems already dealing with chromium-6 contamination could quadruple the number of cancer cases avoided compared to treating chromium-6 alone.

States like California, Arizona, and Texas face the highest burden from arsenic pollution and would benefit most from a multi-contaminant approach. In California alone, nearly eight out of 10 preventable cancer cases linked to drinking water are due to arsenic exposure.

Health risks from these pollutants are particularly severe for children, pregnant people, and residents in small or rural communities, which often rely on groundwater and lack resources to upgrade outdated water systems.

Outdated regulations and cost challenges

Under current regulations, the federal government evaluates each contaminant in isolation, considering costs and benefits pollutant by pollutant. But EWG researchers argue this approach is outdated and leaves millions vulnerable to cumulative health risks from chemical mixtures in drinking water.

“The federal nitrate limit was set decades ago to prevent infant deaths, but we now know cancer and birth complications can occur at much lower levels,” said Anne Schechinger, EWG’s Midwest director.

Nitrate contamination, particularly common in agricultural regions, poses significant health risks including cancer and birth defects. EWG estimates that cutting nitrate levels by just 20% could prevent 130 cancer cases each year and save $35 million in healthcare costs, especially when combined with treatment for arsenic and chromium-6.

Despite proven technologies capable of removing multiple pollutants at once, small water systems face steep costs and limited technical support, leaving many communities exposed to significant health risks.

“This is about more than clean water—it’s about protecting health and advancing equity,” said David Andrews, Ph.D., acting chief science officer at EWG. “We have the engineering solutions to fix the broken drinking water system in the U.S., but we need state and federal policies to reflect the reality people face when they turn on the tap.”

What consumers can do

While policymakers debate reforms, consumers worried about tap water contaminants can take steps to protect themselves. EWG recommends reverse osmosis filters for removing arsenic, chromium-6, and nitrate, though filters must be replaced on schedule to stay effective.

Consumers can also search EWG’s Tap Water Database to learn which contaminants are present in their local water systems.

As concerns grow about drinking water safety across the country, experts say a shift toward multi-contaminant solutions could be key not only to preventing cancer cases but also to promoting health equity and saving millions in healthcare costs.

Environmental groups are pressuring the U.S. Environmental Protection Agency in federal court to complete its review on the dangers of the pesticide atrazine, which could lead to a ban of the chemical.

Atrazine is already banned in 60 countries after it was found to pollute water and have links to birth defects, cancer and fertility problems, nonprofit Center for Food Safety said Wednesday.

But atrazine remains the second-most-widely-used herbicide in the U.S, the Center for Food Safety said. 

Environmentalists said the Biden administration delayed its court-mandated review of atrazine danger's to wildlife for more than three years and the responsibility now falls to the Trump administration.

"The Trump administration has the opportunity, right now, to undo decades of cowardly inaction on atrazine and create a sweeping, signature achievement for everyone's health by banning this nasty stuff," said Nathan Donley, environmental health science director at the Center for Biological Diversity, in a press release.

Nothing short of a complete ban ...

"Nothing short of a complete ban on atrazine will end the harm this extraordinarily dangerous pesticide is doing to human health and the thousands of waterways it has poisoned," he added.

Atrazine has also found critics among Trump's supporters, including commentator Alex Jones, who said it turned frogs gay, and recently-confirmed Health and Human Services Secretary Robert F. Kennedy Jr., who said it was contributing to gender confusion among young people.

The EPA didn't immediately respond to ConsumerAffairs's request for comment.

Nearly 90% of atrazine is sprayed on corn people don't eat that is fed to animals, said George Kimbrell, legal director at Center for Food Safety and attorney on the case, in a press release.

"Atrazine is not necessary to grow healthy food or help farmers, making its continued use and the delay of judicial review of its unlawful approval all the more infuriating," he said.

Email Dieter Holger at dholger@consumeraffairs.com.