A global survey found harmful levels even in water samples taken far any obvious source of contamination.They’re in makeup, dental floss and menstrual products. They’re in nonstick pans and takeout food wrappers. Same with rain jackets and firefighting equipment, as well as pesticides and artificial turf on sports fields.They’re PFAS: a class of man-made chemicals called per- and polyfluoroalkyl substances. They are also called “forever chemicals” because the bonds in their chemical compounds are so strong they don’t break down for hundreds to thousands of years, if at all.They’re also in our water.A new study of more than 45,000 water samples around the world found that about 31 percent of groundwater samples tested that weren’t near any obvious source of contamination have PFAS levels considered harmful to human health by the Environmental Protection Agency. About 16 percent of surface water samples tested, which were also not near any known source, have similarly hazardous PFAS levels.This finding “sets off alarm bells,” said Denis O’Carroll, a professor of civil and environmental engineering at the University of New South Wales and one of the authors of the study, which was published on Monday in Nature Geoscience. “Not just for PFAS, but also for all the other chemicals that we put out into the environment. We don’t necessarily know their long-term impacts to us or the ecosystem.”High levels of exposure to some PFAS chemicals have been linked to higher cholesterol, liver and immune system damage, hypertension and pre-eclampsia during pregnancy, as well as kidney and testicular cancer.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The 8th update to a major international report shows more people are getting sick and dying from extreme heat, drought and other climate problems.Climate change continues to have a worsening effect on health and mortality around the world, according to an exhaustive report published on Tuesday by an international team of 114 researchers.One of the starkest findings is that heat-related deaths of people older than 65 have increased by 85 percent since the 1990s, according to modeling that incorporates both changing temperatures and demographics. People in this age group, along with babies, are especially vulnerable to health risks like heat stroke. As global temperatures have risen, older people and infants now are exposed to twice the number of heat-wave days annually as they were from 1986 to 2005.The report, published in the medical journal The Lancet, also tracked estimated lost income and food insecurity. Globally, exposure to extreme heat, and resulting losses in productivity or inability to work, may have led to income losses as high as $863 billion in 2022. And, in 2021, an estimated 127 million more people experienced moderate or severe food insecurity linked to heat waves and droughts, compared with 1981-2010.“We’ve lost very precious years of climate action and that has come at an enormous health cost,” said Marina Romanello, a researcher at University College London and the executive director of the report, known as The Lancet Countdown. “The loss of life, the impact that people experience, is irreversible.”The indicators of public health tracked in the report have generally declined over the nine years the researchers have produced editions of the assessment.The analysis also examined health outcomes for individual countries, including the United States. Heat-related deaths of adults 65 and older increased by 88 percent between 2018 and 2022, compared with 2000-04. An estimated 23,200 older Americans died in 2022 because of exposure to extreme heat.For health practitioners, the statistics are not abstract or faceless.“These numbers remind me of the elderly patients I see in my own hospital with heatstroke,” said Dr. Renee Salas, an emergency medicine physician at Massachusetts General Hospital and Harvard Medical School.Dr. Salas is one of the report’s co-authors and said she viewed the project like tracking vital signs in a patient, but on a national and international scale.The data can help fill a gap for federal policymakers.“We have a limited set of indicators for climate change and health that are routinely collected in the United States,” said Dr. John Balbus, director of the office of climate change and health equity in the U.S. Department of Health and Human Services. He did not contribute to this report and is not currently involved with The Lancet Countdown, but previously served as a scientific adviser to the project’s funder.Dr. Balbus cautioned that this report mostly measures people’s exposure to climate-related risks rather than actual health outcomes, such as rates of disease. In order to get from exposures to real health outcomes, he said more investment in research was needed.For the first time, this year’s Lancet Countdown included projections for the future. If the global average temperature rises by 2 degrees Celsius compared with pre-industrial temperatures, an increasingly likely future unless society significantly reduces greenhouse gas emissions, the number of heat-related deaths each year will increase by 370 percent by the middle of this century, the report found.At the same time, the researchers point out that reducing fossil fuel pollution is proving beneficial for global health. Deaths from air pollution related to fossil fuels have decreased by 15 percent since 2005, with most of that improvement a result of less coal-related pollution entering the atmosphere.The value of The Lancet Countdown is its ongoing monitoring of climate change’s effects on global health, said Sharon Friel, director of the Planetary Health Equity Hothouse at the Australian National University.Dr. Friel was not involved in the report, but read it and wrote an accompanying commentary.Dr. Howard Frumkin, a former special assistant to the director for climate change and health at the Centers for Disease Control and Prevention, said the report was a valuable dashboard but that the climate impacts he most worried about were not the obvious ones highlighted. Researchers and policymakers need to pay attention to the health effects of people being displaced by climate change and migrating, Dr. Frumkin said.“If you’re on cancer chemotherapy or if you are getting kidney dialysis or if you’re getting addiction treatment and you have to move suddenly, that’s terribly disruptive and threatening,” he said. Dr. Frumkin was not involved in the new report but was a co-author on previous editions.Over the years, the health experts involved in this project have included more research about the continued use of fossil fuels being the root cause of health issues.“The diagnosis in this report is very clear,” Dr. Salas said. “Further expansion of fossil fuels is reckless and the data clearly shows that it threatens the health and well-being of every person.”The researchers point out that health care systems, and other societal infrastructure health care depends on, haven’t adapted quickly enough to our current level of global warming.“If we haven’t been able to cope today, chances are we won’t be able to cope in the future,” Dr. Romanello said.The report is likely to be discussed at the annual United Nations climate summit in the United Arab Emirates that starts in a few weeks. This year the summit will include a greater focus on human health.

As concerns over wildfires and air quality mount, drones and laser shows offer an alternative to fireworks on July 4 and other holidays.The American practice of setting off fireworks on July 4 stretches back to the first Independence Day celebration in Philadelphia in 1777. Today, it’s a beloved tradition that almost seems impossible to replace.But with concerns over air quality, wildfires and supply chains, some cities are doing just that.This year Salt Lake City is replacing its fireworks with synchronized dancing drone displays to avoid worsening air quality and setting off more wildfires. Boulder, Colo., is switching to drones, too, and Minneapolis is opting for lasers, simply because those technologies have been easier to source than fireworks in recent years.And as wildfire smoke from Canada again blanketed much of the United States last week, New York City officials debated whether to set off fireworks on the 4th but, as of Monday night, had not called them off.Across the border, Montreal canceled July 1 Canada Day fireworks, citing poor air quality from the more than 100 wildfires burning across Quebec.“They’re definitely going to compound those existing sources of air pollution,” said Grace Tee Lewis, an epidemiologist at the Environmental Defense Fund who specializes in air pollution and public health.Fireworks cause a spike in a form of air pollution called particulate matter, the same type of pollution that is elevated from wildfire smoke. While there’s not much research on the risks of fireworks specifically, particulate matter less than 2.5 microns wide (about one-30th the width of a human hair) is known to enter people’s lungs and bloodstreams and cause breathing problems and inflammation. Children, older people and those with existing health conditions like asthma and chronic heart disease should take special care, Dr. Tee Lewis said.“Watch it from a distance,” she recommended. “The closer you are, the more particulate matter exposure you’re going to have.”Dr. Tee Lewis added that since the spread of the coronavirus, more people may be more vulnerable to air pollution, especially people suffering from long Covid or heart complications as a result of their infections. For those determined to get their pyrotechnic fix, wearing the same N95 face masks that protect against the virus is one way to protect yourself from smoke and air pollution, she said.On July 4 and 5, fine particulate matter levels across the country rise by 42 percent on average, according to a 2015 study by the National Oceanic and Atmospheric Administration. Alongside the fireworks party, particulate matter pollution can rise as much as 370 percent.These levels often exceed what’s allowed by the Environmental Protection Agency for day-to-day outdoor air quality, but local, state and tribal governments are generally allowed to flag one-time events like fireworks, as well as wildfires, as “exceptional events” and avoid officially violating national air standards.A drone show in Windsor, England, during coronation celebrations for King Charles III.Leon Neal/Pool via ReutersA New Year’s Eve show in Singapore.How Hwee Young/EPA, via ShutterstockA drone show for the Bordeaux Wine Festival in June.Romain Perrocheau/Agence France-Presse — Getty ImagesOther countries see similar spikes in air pollution around their own major holidays, said Dian Seidel, an author of the 2015 study and a retired NOAA climate scientist.Background air pollution from wildfire smoke is certainly something for cities to consider as they plan fireworks or alternative celebrations like drone shows, Dr. Seidel said. “Maybe there are ways not to be a party pooper, but to still have something pretty in the sky to look at, and not cause a big amount of pollution,” she said.Maps: Tracking Air Quality and Smoke From Canada WildfiresSee maps of where smoke is traveling and how harmful the air has become across the region.Besides air pollution, fireworks come with other risks. Dogs and other household pets are known to hate July 4, and many humane societies and animal shelters prepare for an influx of lost or runaway pets after the holiday. Fireworks lead to problems for wild animals, too. A 2022 study of wild geese in Europe found that during crucial rest stops on their long migrations, many birds abandoned their sleeping sites on New Year’s Eve.In 2022, Americans suffered an estimated 10,200 fireworks-related injuries and 11 reported deaths, according to the U.S. Consumer Product Safety Commission. Many of the injuries resulted from smaller firecrackers and sparklers set off by people at home, not during large public or commercial shows.But the adrenaline rush of sparks, whistles and booms, and a little bit of danger, socially acceptable for one day, is exactly why so many people love fireworks. Even Dr. Tee Lewis said her children set off small July 4 fireworks at their grandparents’ house, where they are legally allowed.She and Dr. Seidel don’t want to stop the holiday festivities. They simply urge caution, and for people to consider alternatives.In the end, holiday fireworks lead to just a couple of days of particularly visible air pollution. Around the country and around the world, communities deal with less visible but still unhealthy air daily or seasonally from things like vehicle traffic, industrial pollution and wildfires.This year, the E.P.A. proposed strengthening its air quality standard for fine particulate matter to better protect public health, but said it would still allow special consideration for “exceptional events.”

As smoke from wildfires crosses state and international borders more frequently, tracking and studying it is increasingly important for shaping air quality and health measures around the world.An upcoming study from researchers at Stanford University offers a new way to trace far-flung smoke and pollution back to individual wildfires of origin.What’s burning in a wildfire determines what kind of pollution is in the smoke. A forest fire burns differently from a fire in a swamp, or a fire that burns buildings. As smoke travels, its chemical composition may change with time and distance.The findings could help officials to determine which wildfires are likely to have the biggest health consequences for the greatest number of people, and to allocate firefighting resources accordingly.“We don’t find that fire suppression resources are often spent on the fires that are most damaging from a health perspective,” said Jeff Wen, a Ph.D. candidate in Earth system science at Stanford and the study’s lead author.Others have done similar research before, but at a much smaller scale. The new study, not yet peer reviewed, would be the first to cover the whole contiguous United States, according to the authors.“Historically, we haven’t really been able to study those types of questions at a broad spatial, temporal scale,” Mr. Wen said.It’s clear that wildfires have become more frequent and intense in recent years, fueled in part by climate change’s role in drying out many landscapes. Less clear to scientists has been how smoke from these fires has changed over time. The new study shows that as fires have worsened, so has their smoke: From 2016 to 2020, the U.S. population experienced double the smoke pollution that it did 10 years earlier, from 2006 to 2010. While the study focused on historical data, some of its methods can also be used to predict where smoke from a new fire will travel in the future.The researchers focused on a pollutant called particulate matter, made of very small solid particles floating in the air, which can enter people’s lungs and blood and lead to problems such as difficulty breathing, inflammation and damaged immune cells.A helicopter survey of wildfires burning near Mistissini, Quebec, this month.Canadian Forces, via ReutersUsing their new method, Mr. Wen and his team ranked all of the wildfires observed in the United States from April 2006 to December 2020 by the resulting smoke exposure. They found that the worst fire by smoke exposure during this period was the 2007 Bugaboo Fire, which burned more than 130,000 acres in and around the Okefenokee Swamp, straddling Georgia and Florida.This initially surprised the researchers, since Western states tend to have more large fires. But the Eastern Seaboard is more densely populated, so smoke from the Bugaboo Fire didn’t have to go far to affect many millions of people. Peatlands like the Okefenokee Swamp also tend to burn slowly, Mr. Wen said, releasing more particulate matter into the air.The worst fires in their ranking did not match up very well with the worst fires in traditional rankings, such as acres burned or buildings and infrastructure lost. More firefighting resources were not necessarily deployed to the smokiest fires, either.“We often suppress fires mainly because of structures and immediate threat to life,” said Bonne Ford, an atmospheric scientist at Colorado State University who was not involved in this study. While it’s important to save lives and help rural communities in immediate harm’s way, it’s “short-term thinking” to focus only on those immediately dangerous fires and ignore others that may harm many people farther away through smoke exposure.Dr. Ford and others have studied wildfire smoke patterns, as well as the resulting exposure to particulate matter pollution. But the Stanford researchers have pulled off something new by putting the two together, she said, especially over so many years and so much land area.One aspect of the study Dr. Ford took issue with was treating all human exposure to particulate matter in smoke the same, no matter where it happened. Some people are more vulnerable to air pollution, she said, depending on their age, pre-existing health conditions, other environmental factors and whether they can take precautions such as wearing face masks outside and using air filters inside. Future research could combine Dr. Wen’s methods with existing vulnerability indexes, Dr. Ford said.There are also more precise ways to track and predict where smoke travels, according to John Lin, an atmospheric scientist at the University of Utah who was not involved in the study. Aside from that, Dr. Lin thought the Stanford study would be very useful in figuring out the real human toll of wildfire smoke.Smoke traveling long distances is “the new normal,” he said. This reality challenges the ways governments have historically dealt with air quality, through regulations like the Clean Air Act. Now that pollution is increasingly crossing borders, Dr. Lin said, the way that people manage air quality should evolve accordingly.