The more you dine out, the more you’re getting exposed to
potentially hazardous chemicals known as phthalates, suggests a
new study published Wednesday in the journal Environment
Phthalates are a group of chemicals used to help make plastics
more flexible and durable. They can be found in everything from
cosmetics to children’s toys to medical devices. Most of us,
though, are exposed to low doses of phthalates through
contamination of our food. Research, mostly in animals, has
suggested that certain phthalates can muck with the organs and
glands responsible for making hormones, particularly androgens
In the current study, researchers looked at more than 10,000
people in the US over the age of six who had taken the National
Health and Nutrition Examination Survey (NHANES), an annual
study that combines comprehensive interviews and physical check-
ups, from 2005 to 2014. As part of the NHANES, these volunteers
provided urine samples and a food diary of everything they had
eaten the day before. Because phthalates only stay in our system
for about a day, the researchers used the volunteers’ urine to
estimate their level of total phthalate exposure from food.
“We found that people who eat out more—at full service
restaurants, cafeterias, and fast food restaurants—have nearly
35 percent higher phthalate levels than people who eat at home
more often,” senior author Ami Zota*, an assistant professor of
environmental and occupational health at George Washington
University’s Milken Institute School of Public Health, told
Gizmodo via email.
The team’s earlier research had already suggested that fast food
contains higher levels of phthalates, but the latest study is
the first to take a deep look at all kinds of food prepared
outside the home and across different age groups, Zota said.
The findings are relevant for everyone, since two-thirds of the
study sample had dined out recently. But they’re especially
relevant for children, according to Pam Factor-Litvak, an
epidemiologist at Columbia University who has studied phthalate
exposure in expecting mothers and young children.
“They’re developing, and hormone balance is really important for
them,” said Factor-Litvak, who is unaffiliated with the new
study. “So anything that interferes with that is potentially
Two phthalates in particular accounted for 75 percent of the
total phthalate exposure found in the study, known as di(2-
ethylhexyl) phthalate (DEHP) and di-isononyl phthalate (DiNP),
respectively. Studies have specifically found an association
between DEHP with conditions like childhood asthma, while other
research has linked DiNP, intended as a replacement for older
phthalates, to lower cognition or behavioral problems in
children. Both these phthalates are abundant in food packaging,
“It’s very likely that the exposure for children comes mostly
from packaging,” she said, “and especially from these two
Children overall had the highest levels of phthalates in their
system, while the greatest difference in phthalate exposure
between diners and non-diners was seen in teens.
In recent years, agencies like the World Health Organization
have looked at the research behind phthalate exposure. Their
2012 report concluded that while there’s still a lot of work
needed to untangle the connection between phthalates and human
health, there’s enough evidence that exposure during fetal
development and puberty can help cause an array of complications
like genital birth defects, infertility, asthma, and lower IQ.
In adults, it might be raising the risk of certain cancers,
obesity, and even Alzheimer’s.
US agencies have similarly expressed concern about phthalates. A
2014 report by the Consumer Product Safety Commission concluded
that up to 10 percent of mothers in the US might be getting
exposed to unsafe levels of phthalates, Zota points out. That
same year, the Environmental Protection Agency instituted a new
rule that would require companies to tell them if they planned
to use phthalates in a new product or application, an action
that would then be reviewed and possibly rejected by the agency.
Both the EPA and agencies like the Food and Drug Administration
are in the middle of conducting their own reviews of the
evidence (given the EPA’s recent track record, though, that’s
probably more discouraging than it should be).
The US and countries in the European Union have also banned
certain phthalates from being used in children’s toys, while
states like California are planning to mandate that companies
include phthalates and other potentially dangerous chemicals on
their product labels. But there might not be any such thing as a
safe phthalate, Factor-Litvak said. Unlike other toxic chemicals
that need a high enough dose to hurt us, the best evidence
suggests there’s no threshold effect for phthalates.
“That’s troubling because it means even very low levels of
exposure to some of these chemicals is going to be harmful,” she
Zota and her team believe there needs to be a lot more done to
keep phthalates away from people, including removing them from
the food supply entirely.
“There are some things that individuals can do to reduce their
exposure to harmful phthalates. For example, they can dine out
less and prepare more of their meals at home. They can also
increase their intake of fresh foods and decrease their
consumption of processed or packaged foods,” Zota said.
“However, since these chemicals are ubiquitous in our
environment, we also need changes in policy and in the
marketplace to ensure that everyone has greater access to
Zota’s team next plans to conduct research looking into how
exactly phthalates contaminate our food.
*This post originally misspelled Ami Zota’s name. We regret the