When eating out at restaurants, Americans are exposed to far higher levels of certain hormone-disrupting chemicals than when cooking at home, according to the findings of a new study.
Researchers from the University of California’s Berkley and San Francisco campuses found that people who ate fast food, food from restaurants, or cafeteria food ingested 35% more phthalates than those who ate food cooked at home. The findings were published online March 29, in the journal Environmental International.
Phthalates are a group of chemicals used to help make plastic flexible or more durable. They are commonly used as part of the packaging, preparation, storage and processing of food products, but are also found in a wide range of other items, including toys, cosmetics, detergents, PVC tubing, medical devices, and pill coatings.
Studies have found that exposure to phthalates can interfere with hormones and result in widespread harmful side effects. For most people, the diet is the primary source of exposure for most phthalates.
Phthalates often contaminate the food supply when food contacts certain materials. This can occur during industrialized production, but it can even enter the food supply when preparers wearing rubber gloves handle food.
The study focused on dietary intake of phthalates from more than 10,000 participants over the age of 6 using data from the National Health and Nutrition Examination Survey from 2005 to 2014. Researchers compared exposures between food at home and food from fast food and restaurants, calculating daily intake of phthalates from metabolite concentrations in urinary spot samples.
Adolescents had 55% higher phthalate concentrations in their body if they ate fast food or ate out at restaurants, compared to those who ate food cooked at home. Cafeteria food was associated with 15% higher phthalate levels in children and 64% higher phthalate levels in adults.
Sandwiches, such as cheeseburgers, were especially associated with increased levels of phthalates if they were purchased at restaurants or fast food establishments. The findings appear to support a study published last year indicating that one-third of all fast food wrappers contain harmful endocrine disrupting chemicals.
A recent study even indicated high levels of phthalates were found in cheese used to make packaged macaroni and cheese products.
Other studies have shown phthalates are potent endocrine disruptors which affect the function of hormones, including thyroid hormones, increased risk of miscarriage, and reduced male fertility, even for generations after initial exposure.
“Dining out may be an important source of biologically relevant cumulative phthalates exposure among the U.S. population,” the researchers concluded. “Future studies should evaluate modifiable production practices that remove phthalates from the food supply in addition to efficacy of interventions that promote eating fresh foods prepared at home.”