We all know that fast food is unhealthy for us, but what about the chemical levels?

FOX's Alex Hein has the details:

This is Housecall for Health.

The next time you add fries to your burger order, you may also be adding extra chemicals. A new study found that people who ate more fast food had higher levels of phthalates than non-consumers, suggesting the quick eats may expose diners to the potentially harmful chemicals.

The study, published in Environmental Health Perspectives, used data from nearly 9,000 participants. About 1/3 of the group, all aged six or older, reported eating some fast food in the prior 24 hours.

Participants reported on their diet and provided urine samples which were tested for breakdown of two specific phthalates, DEHP and DINP.

People with the highest consumption of fast food had 23.8% higher levels of the breakdown product for DEHP and nearly 40% higher levels of DINP, compared to those who didn't eat fast food in the reported time period.

Chronic exposure to phthalates can increase risk to a range of adverse health effects, especially during pregnancy.

For more on this story, check FOXNewsHealth.com.

Housecall for Health, I'm Alex Hein, FOX News.

Follow Alex Hein on Twitter: @Ahlex3889