No free lunch with phthalates on the menu

Americans love going out to eat. In fact, two-thirds of the U.S. population dine out daily, according to our new study. While many of us know that dining out establishments typically serve larger meals that contain more butter, salt, and oil than foods we might prepare at home, how many of us know that chemicals with the potential to harm reproductive health and child development (called phthalates, or “thal-ates”) are also on the menu – even in our school cafeterias?

Our study found that people who dine out at restaurants, cafeterias, and fast food outlets have higher levels of multiple endocrine disrupting phthalates in their bodies. On average, nearly 35% higher than people who eat only at home.

This is especially of concern for pregnant women, young kids and teenagers, who are more sensitive to endocrine disrupting chemicals, which can interfere with hormone action during various stages of development. While phthalates are associated with many health impacts across a lifetime, including infertility, preterm birth, neurodevelopmental problems, obesity, diabetes, and cancer, the National Academy of Sciences (NAS) recently identified certain phthalates as presumed human reproductive hazards, and previously acknowledged their ability to collectively increase risk of genital malformations and other reproductive tract abnormalities in baby boys.

To reflect this reality in our new study, we assessed multiple phthalates in combination by accounting for some being more toxic than others, which is reflective of modern-day exposures and associated health risks.

We found that children 6-11 years old had the highest overall cumulative phthalate levels. Teenagers who consumed the highest percent of their total calories from dining out at restaurants, cafeterias, or fast food outlets had up to 55% higher phthalate levels than teens who strictly ate food from home (which was most likely purchased from the grocery store).

JV Figure 1
Figure adapted from data reported in Varshavsky et al. 2018

Phthalates are used widely in everyday consumer and personal care products, ranging from perfume to vinyl flooring, and some are restricted in children’s toys. However, most of our phthalate body burden comes from food. Phthalates are not intentional food ingredients but instead contaminate food products by migrating from various food contact materials along the food production supply chain (e.g. from conveyer belts, industrial tubing, food handling gloves, takeout food containers, and other food packaging materials).

While we knew that phthalate sources include fast food and many household food products, such as meat/poultry, dairy products, olive oil, and even spices, we didn’t know whether other dining out sources may contribute to phthalate levels or how dining out compares to eating at home. Our study found that full-service restaurants and cafeterias are probable sources of phthalates exposure and that dining out is associated with higher phthalate levels than consuming food from the grocery store.

Cafeteria sources of phthalates exposure are particularly relevant for children and adolescents, many of whom depend on the National School Lunch Program as a vital source of nutrition. The program provides 30 million school lunches daily across 95% of U.S. public and private schools.

Fast food, restaurant, and cafeteria food appear to contribute about equally to teen’s phthalate levels. The cafeteria food contribution was relatively low in children (15% compared to ≥ 45% in adolescents), despite more children consuming cafeteria meals than teenagers or adults. Different lunch options and food choices may partially explain this discrepancy; teenagers are typically served and often choose  lower quality foods than younger kids in the lunch room, which may increase phthalate levels.

JV Figure 2
Figure adapted from data reported in Varshavsky et al. 2018

Our study suggests that other sources besides dining out contribute to high phthalate levels in children, but our findings also show that school lunches may provide unique opportunities to reduce exposure in children and teens.

As a scientist, I know we need more research. As a mother of a two year old son, I want to act on what we do know. Phthalates have no place (or purpose) in our school cafeterias. Many schools are outsourcing meal preparations off-site, where fresh ingredients undergo processing into less healthy alternatives, which may increase school lunch contamination. Overly processed deep-fried meals can be modified to include healthier, fresh ingredients.

Ultimately, adequate, nutritious meals are the most important factors in healthy development. Other benefits include healthier diet preferences, reduced risk of obesity, and improved test scores. While our findings are not a reason for kids to avoid the school cafeteria – they are a reason for policy makers, food service providers, and others to take action and eliminate phthalates from school lunches.

Many phthalates are already banned from children’s toys; why are we serving them to kids at lunch?

My co-authors on this study were: Rachel Morello-Frosch at the University of California, Berkeley, School of Public Health, Tracey Woodruff, Director of the Program on Reproductive Health and the Environment (PRHE) at the University of California, San Francisco, and Ami Zota at George Washington University, Milken School of Public Health.

PRHE’s Toxic Matters brochure provides practical tips on how to reduce potentially harmful chemical exposures in everyday life.

About the Author

Julia Varshavsky, PhD is a professor of health sciences at Northeastern University in Boston, MA, and an environmental heath scientist and environmental epidemiologist who cares about protecting the public from environmental chemical exposures. She was formerly a postdoctoral scientist with PRHE.