Phthalates – what are they, and what you can do to avoid them

Phthalates are chemical substances widely used in plastics to increase their flexibility, transparency, and durability.  They are of concern because recent studies have shown that they may affect human health by being endocrine disruptors.  This means that they may affect the fetus during pregnancy, and my also be implicated in reduced fertility, obesity, diabetes, endometriosis and some cancers.  There is concern that the development of the male fetus and male fertility may be especially affected.  

A recent study from the University of California in Berkeley and San Francisco, and George Washington University,found that people who ate out more regularly tended to have significantly higher levels of phthalates in their urine.  Researchers looked at people consuming food from restaurants, cafeterias, fast-food locations, or other dining establishments. They analyzed data on 10,253 people who were 6 years and older that was collected from 2005 to 2014 as part of the National Health and Nutrition Examination Survey (NHANES). This data included phthalate concentrations from their urine samples and the frequency at which they ate out versus at home. Those who regularly ate out had 35% higher phthalate levels than those who did not. This difference was even higher for adolescents: 55%. The culprit didn't seem to be the core ingredients of the food, but possibly something involved in the preparation of the food. For example, the study revealed that eating sandwiches (including cheeseburgers) prepared outside the home was associated with higher urine phthalate levels compared to eating sandwiches prepared at home. Many eating establishments use plastic containers, machine parts, packaging, and other items to handle, process, and store food. Phthalates are chemicals used in many plastic items to help them become more flexible. Therefore, phthalates may be leeching from all of these plastic items into the food that subsequently goes into your mouth.   

Here are some ways to decrease your exposure to plastics, according to the Natural Resources Defense Council . You can’t eliminate all plastic, but you can take some easy steps to reduce your plastic use. Swap plastic food storage containers with glass or stainless steel; if you do keep plastic ones, don’t use them to store fatty foods, and never microwave them. Replace plastic bags with reusable lunch bags, and plastic cling wrap with beeswax-coated cloth. Choose hard wood blocks and cotton baby dolls over plastic ones. In short, anytime you’re in the market for something plastic, research whether safer alternatives exist. Canned foods can make meal prep a breeze, but those cans are likely lined with BPA to keep them from corroding. Even cans labeled “BPA-free” may use a similar chemical that hasn’t been proved any safer. Choosing fresh, frozen, or dried foods (like beans) that aren’t packaged in cans is a smart preventive measure. Aseptic “brick” cartons or glass packaging are both better than cans.  Finally – eat at home!

Sadja Greenwood, MD, MPH