(The Hill) — A new study has revealed that melatonin gummies advertised to help with sleep may have potentially harmful levels of the hormone, as well as cannabidiol (CBD) that was not labeled on the packaging.

A study published Wednesday in the medical journal JAMA investigated 25 different gummy brands that were labeled with “melatonin” and were also listed in the National Institutes of Health’s Dietary Supplement Label Database. The study found that 88 percent of the gummies investigated were inaccurately labeled, with only 12 percent containing within 10 percent of the quantity that was labeled.

One of the products that was labeled as including melatonin was actually found to have no traces of the hormone but contained 31.3 milligrams of CBD. The amount of CBD found across all the products ranged from 10.6 to 31.3 milligrams, but only five products included CBD in the label.

The study found that the “actual quantity” of  CBD in the gummies ranged from 104 to 118 percent of the labeled amount. According to the Food and Drug Administration (FDA), it is currently “illegal to market CBD by adding it to a food or labeling it as a dietary supplement.”

The FDA did not immediately respond to a request for comment.

The study said that about 1.3 percent of children in the United States used melatonin for sleep and relaxation concerns before the COVID-19 pandemic, which could place them at risk of ingesting potentially high amounts of melatonin. Melatonin gummies could also resemble candy, which could result in accidental ingestion by children.

The study noted that from 2012 to 2021, the number of calls for children ingesting melatonin to the Poison Control Centers increased 530 percent. During the same period, 4,097 hospitalizations, 287 intensive care unit (ICU) admissions and two deaths were associated with pediatric ingestion of melatonin.

Pieter Cohen, who co-authored the study, told CNN that the researchers looked into melatonin gummies because parents are more likely to give children an edible supplement as opposed to a capsule. He also accused the FDA of not enforcing the law, saying that the manufacturers of the products were not following the regulations.

“The regulatory framework for supplements is broken,” Cohen said, “The manufacturers are not complying with the law, and the FDA is not enforcing the law. So what that means is that we have a lot of poor-quality products out there.”