An analysis of 108 batches of antiperspirants from 30 different brands conducted by the independent lab Valisure found that more than half of them contained detectable levels of the cancer-causing chemical benzene. The chemical is known to cause leukemia and other life-threatening blood disorders.

The Food and Drug Administration classifies benzene as a "Class 1 solvent" and warns that it "should not be employed in the manufacture of drug substances, excipients, and drug products because of their unacceptable toxicity," Valisure explained in a blog post.

However, the FDA does have an emergency exemption for some products and allows them to contain two parts per million of the chemical. Valisure said that the temporary exemption does not apply to products like body sprays and deodorants.

The report, which was published last month, resulted in Procter & Gamble issuing a voluntary recall of 17 different Old Spice and Secret antiperspirant products. Valisure said that two lots of Old Spice had over 17 parts per million of benzene, nearly nine times the FDA limit. However, the company said it has not received any reports of adverse reactions due to the high levels of benzene.

Proctor & Gamble explained that the benzene contamination likely came from the propellant used to make the aerosolized body spray.

"Due to the highly specialized nature of aerosol products, we use a manufacturing partner to produce these products," Kate DiCarlo, senior director of communications for the Personal Care Portfolio of P&G, said, according to CNN. "That manufacturing partner identified an issue with their propellant supply and is implementing additional measures to address the issue identified in the investigation."

No recalls have been issued for other products identified as having trace amounts of benzene, including Tag, Sure, Equate, Suave, Right Guard, and Brut. They all had levels of benzene above the 2 ppm limit set by the FDA.

"The detection of high levels of benzene in body sprays is cause for significant concern since these products are often used daily, by both adults and adolescents," says David Light, Founder and CEO of Valisure. "These findings build upon our now validated discovery of benzene in sunscreens, after-sun care products, and hand sanitizers that have already been followed by national recalls earlier this year. With this latest development, we have identified a concerning trend of carcinogen contamination in consumer healthcare products."