Food preservatives present in the processed foods may harm the body’s immune system, according to a new study.

The findings suggested that the preservative tert-butylhydroquinone, or TBHQ, can harm the immunity in both animal tests and in non-animal tests. TBHQ has been used in all kinds of foods. It offers no benefits besides increasing a product’s shelf life.

In the study, the research team found that TBHQ affected immune cell proteins at doses similar to those that cause harm in traditional studies.

“The pandemic has focused public and scientific attention on environmental factors that can impact the immune system,” said researcher Olga Naidenko from the US-based Environmental Working Group.

“Before the pandemic, chemicals that may harm the immune system’s defense against infection or cancer did not receive sufficient attention from public health agencies. To protect public health, this must change,” Naidenko added.

For the study, the researchers used data from the Environmental Protection Agency’s Toxicity Forecaster or ToxCast. They analysed the health hazards of the most common chemicals added to food, as well as the “forever chemicals” known as PFAS, which can migrate to food from packaging.

They examined all publicly available studies that show how PFAS migrate to food from packaging materials or processing equipment.

The study was published in the International Journal of Environmental Research and Public Health.