The Puyallup River is the second most polluted in the Puget Sound area and its salmon runs are being harmed, which in turn hurts orcas. Scientists are studying where PCBs and other contaminants are coming from.
Many older cats suffer from health problems caused by a hyperactive thyroid, and while there's no single cause of the condition, hormone-disturbing chemicals in the environment are thought to be an important factor.
In the 2000s, California banned a class of toxic fire retardants called PBDEs, which were put in household items like furniture and electronics. But now the chemicals used to replace them may also be negatively impacting fish and humans.
The levels of harmful flame retardants in children's blood are dropping every year, according to a new study of kids from New York City.
The flame retardants—polybrominated diphenyl ethers (PBDEs)— were used for decades in furniture, electronics and clothing in an effort to slow the spread of flames if they catch fire. The chemicals were voluntarily phased out starting in 2004 because they build up in the environment and people—PBDEs are found in the air (in and outside our homes), some food, and in people all around the world.
People are mostly exposed by breathing in contaminated dust. The chemicals are linked to a host of health problems, including impaired brain development, altered thyroid hormones, lower IQs in exposed children and some birth defects.
The new study in NYC, which followed 334 mothers and their children from 1998 to 2013, is the first to show a decline in PBDEs in kids' blood and shows that, despite the chemicals' persistence, bans or phase-outs can reduce children's exposure.
"These findings reinforce the decision to phase-out PBDEs from consumer products," said co author Julie Herbstman, an associate professor and researcher at the Columbia University Mailman School of Public Health, in a statement.
The initial phase-out of PBDEs in 2004 was voluntary. Since then some states have banned PBDEs and the U.S. Environmental Protection Agency and chemical companies agreed to a phase-out of almost all PBDEs by 2014.
Herbstman and colleagues tested the mothers' umbilical cord blood, and the kids' blood at ages 2, 3, 5, 7 and 9. The most common PBDE chemical—BDE-47—decreased in the blood about 5 percent every year. When they only looked at the blood after birth, the levels dropped about 13 percent every year.
This isn't the first time phase-outs have been linked to sharp decreases in PBDE exposure: in 2016, researchers reported that levels of the chemicals in Bay Area women's breast milk dropped nearly 40 percent about a decade after California banned the compounds in 2006.
However, lead author Whitney Cowell, a pediatric environmental health research fellow at Mt. Sinai, cautioned about being overly optimistic: The chemicals "continue to be detected in the blood of young children nearly 10 years following their removal from U.S. commerce," she said in a statement.
They found PBDEs in 80 percent of the cord blood samples and every single sample of kids tested from 2 to 9 years old. She also pointed out that since the PBDE phase-out began, scientists have been finding replacement chemicals in children's blood.
As PBDEs are replaced by other chemicals, Cowell and colleague wrote that increasingly PBDE-contaminated products will end up in landfills, so the chemicals may more frequently leach into water supplies—which could "trigger a transition in human exposure pathways from dust to dietary sources," they wrote.
We've all heard the old adage—"the dose makes the poison." Well—for many pollutants—it may be time to reexamine that.
Some of the most common, extensively tested chemicals — radon, lead, particulate matter, asbestos, tobacco and benzene — appear to be proportionally more harmful to a person's health at the lower levels of exposure, according to a new review of decades of research.
"Not only is there no apparent safe levels or thresholds, but at the lowest levels of exposure, there is a steeper increase in the risk," said author Dr. Bruce Lanphear, a professor and researcher at Simon Fraser University.
The key word here is proportionally—smoking three packs of cigarettes a day for 40 years is obviously worse for your lungs than a little secondhand smoke from time to time. However, the point is that for the nonsmoker exposed to secondhand smoke, the risk is "extraordinarily large," Lanphear said.
Lanphear, a renowned environmental health expert, has for years been a leading voice on how low levels of lead can have big impacts on kids' health. In a commentary published in today's PLOS Biology journal he summarizes key research on low levels of exposure to lead and other toxics and argues, in largely ignoring such exposures, most health and regulatory agencies are not fully protecting public health.
"For toxic chemicals without a threshold … we will inevitably fail to prevent most deaths, diseases, and disabilities, like obesity, heart disease, diabetes, and cancer, until we expand our focus to include population strategies that target people who have low-to-moderate exposures," he wrote.
Lanphear acknowledges it's a tough concept to wrap your head around—most people, including health professionals, think of safe levels or thresholds for toxics.
"If we took this research seriously, we could prevent a lot of death and disease and disability," Lanphear said. "And that makes me hopeful."
Take this example: In Scotland, a smoking ban in public places led to a 20 percent reduction in heart attacks among nonsmoking adults. It also led to a 15 percent reduction in preterm births among nonsmoking pregnant women.
"We can prevent about 15 percent of preterm births just by environmental regulation," Lanphear said.
Kirk Smith, a professor of Global Environmental Health at University of California, Berkeley, said Lanphear raises an "intriguing and potentially profound set of issues" that many in the scientific community have been talking about for years.
He cautioned, however, that measuring people's exposure to various pollutants is a complex and sometimes inconsistent science. "Certainly the idea of thresholds are going by the wayside," he said. "But having the EPA change all the regulations around air pollution or other pollutants? Not yet."
Smith quoted the late scientist Carl Sagan: "Extraordinary claims require extraordinary evidence."
"It is an extraordinary claim, and I don't think we have extraordinary evidence yet, but it's nevertheless an intriguing hypothesis," Smith said of Lanphear's paper.
The company scraps planned Pennsylvania investments and will instead shut down three polluting batteries in 2023. The announcement comes a week after a study shows lower lung function in people living near its Pittsburgh-region facility.