Common plastic chemicals linked to 356,000 annual heart disease deaths worldwide
Green Science Policy Institute
Chemicals used to make plastics more flexible are linked to
more than 356,000 deaths annually across the globe, creating what researchers
called a “substantial global health burden,” according to a new peer-reviewed
study.
The study, published Tuesday in the journal eBiomedicine, is the first to estimate heart
disease deaths from exposure to di-2-ethylhexyl phthalate (DEHP), a class of
phthalate chemicals that are used in raincoats, food packaging, shower
curtains, PVC flooring and pipes, IV bags and other items. The chemicals make
plastics softer and more pliable but are associated with multiple health
problems, including hormone disruption, obesity, diabetes, infertility, cancer
and heart problems.
The study does not prove DEHP causes heart-related deaths,
however, it adds to evidence that exposure to the widespread chemicals
— and the plastics that carry them — could raise people’s risk of heart
disease.
The new study comes as US regulators are undertaking a risk
evaluation of DEHP to see if it requires further regulation and are accepting public comments on the review until May 6.
The study also adds to a global debate over how to limit plastics and other
chemicals linked to human and environmental health problems.
The researchers used environmental and health data from 200 countries and territories to estimate DEHP exposure and compared this to 2018 mortality data from the Institute for Health Metrics and Evaluation, an independent population health research organization. The researchers estimated DEHP exposure contributed to 356,238 deaths, which represents 13% of all global deaths from heart disease in 2018 among people aged 55 to 64. The authors calculated these premature deaths caused a $510 billion economic burden.
People from countries in the Middle East, South Asia, East
Asia and the Pacific accounted for roughly half the estimated deaths. India had
the highest estimated DEHP-linked heart disease death total, with more than
100,000.
“This study uncovers a substantial global health burden
attributable to DEHP exposure,” the authors wrote. “These data highlight
critical global disparities in loss of life due to plastics pollution.”
It’s not entirely clear why these countries had such a large
proportion of the deaths, said study senior author Dr. Leonardo Trasande, a
professor of pediatrics at the NYU Grossman School of Medicine.
Phthalate impacts to heart health
The findings build on a 2021 study from the authors that
tied phthalates to roughly 50,000 premature deaths among older people in the US
each year, mostly from heart disease. In addition, a 2023 review found that most recent studies examining
the link between phthalates and heart problems found an association, including
strokes, arrhythmias, hypertension and other problems.
It’s not entirely clear how phthalates, including DEHP,
could impact the heart. But researchers say they could potentially disrupt
receptors that are crucial for metabolism and increase oxidative stress
— both of which can lead to heart problems and disease.
Laura Vandenberg, a researcher and professor of
environmental health sciences at University of Massachusetts Amherst School of
Public Health & Health Sciences, said it’s likely that the heart disease
link is due to these “indirect” effects of phthalates, including DEHP.
“Phthalates, in general, are known on a molecular level to
increase levels of oxidative stress, and also to serve as obesogens and
metabolic-disrupting chemicals,” Vandenberg said. Obesogens refer to
chemicals that cause our bodies to produce more fat.
Obesity is a risk factor for heart disease, and oxidative
stress, which causes cell damage, can lead to heart problems as well.
Microplastics and nonplastics “carry chemicals along for the
ride,” Trasande said, but it’s possible the tiny bits of plastics themselves
also might be causing tissue injury, leading to heart impacts.
When asked about the new study, Kevin Ott, executive
director of the Flexible Vinyl Alliance, which advocates for use of PVC
plastics, pointed to a 2018 US Food and Drug Administration (FDA) study
that stated there hadn’t been a human health study that connected phthalates
and human health impacts.
“Phthalates, in general, are known on a molecular level to
increase levels of oxidative stress, and also to serve as obesogens and
metabolic-disrupting chemicals.” -Laura Vandenberg, University of Massachusetts
Amherst
Academic studies, however, are consistently at odds with the
FDA stance. A large 2022 study that reviewed phthalates human health
research found links to multiple health problems and that “health risks can
occur at exposure levels below the ‘safe dose’ levels set out by
regulators.”
The Flexible Vinyl Alliance petitioned the FDA in 2018 to remove 23 phthalates
from use in any materials that contact food during processing, packaging
storage or handling, saying that industry had already stopped using them. The
FDA accepted the petition in 2022, revoking the authorizations. However, DEHP
remains in use and the alliance has supported its continued use, along with
three other remaining phthalates used in food materials, saying in a letter to the FDA the chemicals are
“minimally used” and remain “safe for their intended use when deployed for food
contact and food packaging.”
Trasande said the safest way to minimize health risks from
chemicals is to “regulate by class.”
“We’ve had a bunch of problems with regrettable
substitutions,” he said. “If we reduce DEHP I’m not convinced you’ll reduce
this mortality. But if you reduced plastic use or phthalates as a class, you
would.”
An “opportunity” to get DEHP out of products
Globally, about 3 million to 4 million tons of DEHP are produced each year, representing
about 40% of chemicals used to make plastics softer. Under
the Toxic Substances Control Act the US Environmental Protection Agency (EPA)
considers DEHP a “high priority substance,” which triggered a risk evaluation –
happening now – to see if it requires further regulation. The agency,
which already has a 6 parts per billion limit for DEHP in drinking water,
is accepting public comments on the DEHP review until May
6.
There’s an “opportunity to get DEHP out of as many products
as possible,” said Judith Enck, president of Beyond Plastics, a nonprofit
organization that fights plastic pollution.
She added that DEHP has “not been studied enough” and
pointed out that “millions of Americans get drinking water from PVC pipes,”
which contain DEHP.
“After 40 or 50 years many cities are getting around to
replacing lead service lines and we don’t want to replace those with PVC,” she
said, adding that Beyond Plastics is advocating for copper lines.
Trasande said the best available data suggests our diets are
the main route of exposure for DEHP, but it’s not clear that’s the case across
the globe. He suggested some simple steps that won’t “break the bank” to limit
exposure including using glass and stainless steel containers instead of
plastic, not microwaving plastic and looking at recycling numbers, as #3 is for
PVC plastics that could contain phthalates.
