SUBSCRIBE TO OUR FREE NEWSLETTER
Daily news & progressive opinion—funded by the people, not the corporations—delivered straight to your inbox.
5
#000000
#FFFFFF
5
#000000
#FFFFFF
pesticides
'Astonishing' Study Shows Infant Deaths Rise in US When Bat Populations Fall
Experts hailed the study as "groundbreaking" and "sobering" for the connections it draws between ecosystem and human health.
Sep 06, 2024
Bat die-offs in the U.S. led to increased use of insecticides, which in turn led to greater infant mortality, according to a "seminal" study published Thursday that shows the effects of biodiversity loss on human beings.
Eyal Frank, an environmental economist at the University of Chicago, authored the study, which was published by Science, a leading peer-reviewed journal.
Bats can eat thousands of insects per night and act as a natural pest control for farmers, so when a fungal disease began killing off bat populations in the U.S. after being introduced in 2006, farmers in affected counties used more insecticides, Frank found. Those same counties saw more infant deaths, which Frank linked to increased use of insecticide that is harmful to human health, especially for babies and fetuses.
The study was greeted by an outpouring of praise from unaffiliated scientists for its methodology and the important takeaways it offers.
"[Frank] uses simple statistical methods to the most cutting-edge techniques, and the takeaway is the same," Eli Fenichel, an environmental economist at Yale University, toldThe New York Times. "Fungal disease killed bats, bats stopped eating enough insects, farmers applied more pesticide to maximize profit and keep food plentiful and cheap, the extra pesticide use led to more babies dying. It is a sobering result."
Carmen Messerlian, an environmental epidemiologist at Harvard University, told the Times the study "seminal" and "groundbreaking."
The study shows the need for a broader understanding of human health that includes consideration of entire ecosystems, said Roel Vermeulen, an environmental epidemiologist at Utrecht University in the Netherlands. "It emphasizes the need to move from a human-centric health impact analysis, which only considers the direct effects of pollution on human health, to a planetary health impact assessment," he toldNew Scientist.
Reporter Benji Jones echoed that sentiment in Vox, calling Frank's findings "astonishing" and writing that such studies could help us fight chemical pollution by corporations.
"When the link between human and environmental health is overlooked, industries enabled by short-sighted policies can destroy wildlife habitats without a full understanding of what we lose in the process," Jones said. "This is precisely why studies like this are so critical: They reveal, in terms most people can relate to, how the ongoing destruction of biodiversity affects us all."
NEW: This is one of the more stunning (and sobering) studies I've covered in a while:
It found that a decline of bats in the U.S. had come at a deadly cost to human babieshttps://t.co/M82FXxBrtO
— Dino Grandoni (@dino_grandoni) September 5, 2024
Frank, who said he started the work after stumbling on an article about bat population loss while procrastinating, happened upon an excellent natural experiment. The spread of white-nose syndrome, the fungal disease, was well tracked on a county-by-county level, leaving him with high-quality data that is hard to find for researchers who study the intersection of human and animal life.
The benefits of biodiversity on humans, and the drawbacks to its loss, are normally very difficult to quantify.
"That's just quite rare—to get good, empirical, grounded estimates of how much value the species is providing," Charles Taylor, an environmental economist at Harvard Kennedy School, toldThe Guardian. "Putting actual numbers to it in a credible way is tough."
Taylor himself is the author of a somewhat similar study that showed that pesticide use and infant mortality rose during years in which cicadas appeared; the insects do so at 13-17 year intervals.
David Rosner, a historian based at Columbia University, said the new bat study joins a large body of evidence dating back to the 1960s that links pesticide use with negative human health outcomes. "We're dumping these synthetic materials into our environment, not knowing anything about what their impacts are going to be," he said. "It's not surprising—it's just kind of shocking that we discover it every year."
Frank's claim about the cause of increased infant mortality should be taken with some caution, said Vermeulen, the Dutch researcher. He said the loss of agricultural income caused by bat die-offs could be connected to the increased deaths in complex ways.
The exact causal mechanism isn't known, Frank told media outlets, but the data shows the rise of infant mortality didn't come from food contamination by insecticides—rather, it's more likely it came via the water supply or contact with the chemicals.
Frank's other research extends beyond pesticide use. He and another researcher recently estimated that hundreds of thousands of human beings have died in India due to the collapse of the country's vulture population, as rotting meat increased the spread of diseases such as rabies.
Frank is not the first to study the impacts of white-nose syndrome on humans. Other studies have shown a reduction in land rents in counties hit by the bat plague and documented the billions of dollars that farmers have lost as their natural pest control disappeared.
The syndrome attacks bats while they hibernate. It was first identified in New York in 2006 and has since spread to much of North America. It's believed to have been brought over from Europe. It doesn't affect all bat species, but it's killed more than 90% of three key species, and bats also face a myriad of other threats, including habitat loss, climate change, and the dangerous churn of wind turbines.
Frank's bracing study should be a call to arms, experts said.
"This study estimates just a few of the consequences we suffer from the disappearance of bats, and they are just one of the species we're losing," Felicia Keesing, a biologist at Bard College, told The Washington Post. "These results should motivate everyone, not just farmers and parents, to clamor for the protection and restoration of biodiversity."
Keep ReadingShow Less
EPA Takes 'Historic' Step to Halt Dangerous Herbicide Use
"DCPA is so dangerous that it needs to be removed from the market immediately," said an EPA official, but advocates said the move was "long overdue."
Aug 06, 2024
Taking a rare step to "prevent imminent hazard," the U.S. Environmental Protection Agency on Tuesday issued an emergency order suspending all uses of an herbicide that has been linked to irreversible health risks for unborn babies.
The EPA issued the order after years of pushing AMVAC Chemical Corporation, the sole manufacturer of dimethyl tetrachloroterephthalate, to submit data about the risks posed by the chemical, which is also known as Dacthal and DCPA.
The agency estimated in 2023 that a fetus could be exposed to levels of DCPA four to 20 times greater than the safe limit, if a pregnant person handled products treated with the herbicide.
The chemical is used on crops including broccoli, onions, cabbage, and Brussels sprouts in the U.S., but has been banned since 2009 in the European Union.
Exposed fetuses can suffer effects including low birth weight, impaired brain development and motor skills, and decreased I.Q., according to the agency.
"DCPA is so dangerous that it needs to be removed from the market immediately," Michal Freedhoff, assistant administrator for the EPA's Office of Chemical Safety, said in statement. "In this case, pregnant women who may never even know they were exposed could give birth to babies that experience irreversible lifelong health problems."
"Countless people have been exposed to DCPA while the EPA abdicated its responsibility. The agency should have taken action decades ago, when it first identified the human health risks posed by this toxic crop chemical."
The Environmental Working Group (EWG) called the suspension of DCPA "welcome news," but said it was "long overdue." The group's research found that even though the EPA has collected evidence of DCPA's health risks, up to 200,000 pounds of the herbicide were sprayed on crops in California in some recent years.
"For years, EWG and other public health advocates have warned about the serious risks the weedkiller poses to farmworkers, pregnant people, and other vulnerable populations," said senior toxicologist Alexis Temkin. "Countless people have been exposed to DCPA while the EPA abdicated its responsibility. The agency should have taken action decades ago, when it first identified the human health risks posed by this toxic crop chemical."
Mily Treviño Sauceda, executive director of Alianza Nacional de Campesinas, also known as the National Farmworkers Women's Alliance, said the emergency order was "a great first step that we hope will be in a series of others that are based on listening to farmworkers, protecting our reproductive health, and safeguarding our families."
"Alianza is pleased to see the EPA make this historic decision," she said. "As an organization led by farmworker women, we know intimately the harm that pesticides, including dimethyl tetrachloroterephthalate... can inflict on our bodies and communities."
William Jordan, a volunteer with the Environmental Protection Network and a former deputy director for programs in the EPA's Office of Pesticide Programs, noted that the agency made the emergency order and bypassed the lengthy process of canceling DCPA's approval due to the harm the chemical causes—the first time in 40 years that the EPA has taken the step.
"The Environmental Protection Network endorses the strong regulatory action taken by EPA to address the extraordinary risks to unborn children posed by the use of pesticides containing DCPA," said Jordan. "EPA's order immediately suspending all sales, distribution, and use of DCPA products is the only way to avoid the harm to children that would result from continued use of this dangerous pesticide."
Keep ReadingShow Less
Where Have All the Butterflies Gone? Low Count Portends Sad Future for Biodiversity
"The lack of butterflies this year is a warning sign to us all," the director of a U.K. wildlife charity said. "Nature is sounding the alarm and we must listen."
Jul 29, 2024
A U.K. conservation charity sounded the alarm on Monday after a yearly butterfly count turned up a record low number of butterflies so far.
Participants in the count, which runs through August 4, are reporting a little more than half the number of butterflies as they did by this time in 2023, Butterfly Conservation said.
"The lack of butterflies this year is a warning sign to us all," the charity's director of conservation Dan Hoare said in a blog post. "Nature is sounding the alarm, and we must listen. Butterflies are a key indicator species. When they are in trouble we know the wider environment is in trouble too."
"So far this summer, I have not seen a single butterfly alight on the flowers. Desperate times."
The low numbers are one example of how the climate crisis exacerbates biodiversity loss. Butterfly numbers have plummeted by 80% in the U.K. since the 1970s, a decline driven by the climate emergency as well as habitat destruction and pesticide use. This year, the country experienced an abnormally wet, windy spring and a cooler than average summer.
"Butterflies need some warm and dry conditions to be able to fly around and mate," Hoare explained. "If the weather doesn't allow for this there will be fewer opportunities to breed, and the lack of butterflies now is likely the knock-on effect of our very dreary spring and early summer."
The climate emergency increases rainfall because warmer air holds more moisture. Spring 2024 was the U.K.'s sixth wettest on record and the wettest overall since 1986, according toThe Guardian. March, April, and May saw almost a third more rainfall than usual for those months.
The heavy rain also followed a drought in 2022 that put a different kind of pressure on butterfly populations by decreasing the number of plants that caterpillars need to eat. The green-veined white and the ringlet species were especially hard hit and have yet to recover.
"Never known a year like it," author and climate scientist Bill McGuire wrote of 2024. "We have two huge buddleia 'butterfly bushes' that are normally swarming with at least half a dozen species. So far this summer, I have not seen a single butterfly alight on the flowers. Desperate times."
Since the count began on July 11, the number of butterflies reported in the U.K. is the lowest in the count's 14-year history, but there is still a chance that warmer, drier weather could turn things around. However, even if it doesn't, Hoare called for more citizen scientists to participate in the count by spending 15 minutes noting any butterflies and moths they see in a specific area and recording their totals on the website or via app.
"People are telling us that they aren't seeing butterflies, but simply telling us is not enough; we need everyone to record what they are or aren't seeing by doing a Big Butterfly Count as this will give us the evidence we need to take vital action to conserve our butterfly species," Hoare said.
The U.K.'s butterfly decline is not the only recent example of climate extremes harming wildlife. Extreme wildfires in Australia in 2019 and 2020 killed at least 1 billion animals, while a heatwave in Mexico this spring prompted howler monkeys to drop dead out of trees. In 2023 and 2024, the world's coral reefs suffered their fourth mass bleaching event.
The news of the butterflies' decline also follows a week that saw the four hottest days on record globally. 2023 was the hottest year in the past 125,000, and 2024 is expected by many scientists to surpass it. Every month since June 2023 has been the hottest of its kind on record and has seen average temperatures at or above 1.5°C higher than preindustrial levels, the more ambitious temperature goal enshrined in the Paris agreement.
"The extreme events that we are now experiencing are indications of the weakening resilience of these systems," Johan Rockström, director of the Potsdam Institute for Climate Impact Research in Germany, toldThe Washington Post on Saturday. "We cannot risk pushing this any further."
Keep ReadingShow Less
Most Popular