A new report from Consumer Reports magazine released Wednesday found that perchlorate – a chemical commonly used in rocket fuel, missiles and explosives – is also found in several foods, particularly those often consumed by babies and children.

The advocacy group examined 196 samples from 63 supermarket products and 10 fast-food products, which were chosen because previous scientific research suggested that these foods could contain perchlorate. They also analyzed the type of packaging in which each food was delivered.

About 67% of the samples had measurable levels of perchlorate, ranging from levels of just over 2 parts per billion (ppb) to 79 ppb. Overall, children’s foods had the highest levels, averaging 19.4 ppb. Baby food, fast food, and fresh fruits and vegetables also contained elevated levels of the chemical.

In terms of packaging, foods in plastic containers had the highest perchlorate levels, averaging nearly 54 ppb, followed by foods in plastic film and cardboard.

Consumer Reports’ findings come decades after perchlorate was first identified as a contaminant in water and food. In 2003, the Environmental Working Group found perchlorate in nearly 20 percent of supermarket samples it tested, often at high levels. Two years later, the Environmental Protection Agency (EPA) set a safe exposure limit for perchlorate, which it called the “official reference dose,” which was 0.7 micrograms per kilogram of body weight per day. That safety dose has been challenged by many food safety experts, who claim the level is still unsafe and should be lowered. By comparison, the European Food Safety Authority has set a daily intake of less than half that amount, 0.3 micrograms per kilogram of body weight per day.

Perchlorate has been linked to possible brain damage in young children and thyroid and hormone production problems in adults.