In vitro studies have shown that some personal lubricants used during sexual intercourse significantly enhance the replication of the human immunodeficiency virus (HIV) and cause rectal tissue damage, according to Population Council research published in the journal AIDS Research and Human Retroviruses. In vitro experiments are conducted in an artificial environment, such as in a test tube, not in a living organism.
The Population Council research team evaluated 41 of the hundreds of brands available, including a majority of those identified in a survey of users of anal sex lubricants.
Low doses of four Astroglide formulations-Liquid, Warming Liquid, Glycerin & Paraben-Free Liquid, and Silken Secret-substantially amplified HIV replication in these laboratory studies. All of these products contain either polyquaternium or polyquaternium-15.
"We didn't find any polyquaterniums in any of the other lubricant formulations in our studies," noted lead author and Population Council research technician Othell Begay.
Damage to rectal tissue
Council researchers also demonstrated that the majority of the tested lubricants damaged rectal tissue, which may have implications for enhancing HIV transmission in humans.
"It is important to emphasise that our findings are from in vitro studies. What happens in the laboratory environment does not always happen in the human body. In fact, lubricants generally appear to play an important role in preventing the spread of HIV. Intercourse without them can damage cells by creating friction which could cause tears in the epithelium, thus possibly promoting HIV transmission. But we need to know more," said co-author and Population Council senior research investigator José Romero.
Limited information on lubricants
Personal lubricants have been available for decades, but knowledge about their impact on the transmission of STIs, including HIV, is limited. In the United States the Food and Drug Administration requires that manufacturers test lubricants for vaginal irritation, but does not require similar studies to ensure safety for rectal use.
Anecdotal evidence suggests that substances not marketed as lubricants, such as vegetable oils, are used during sexual intercourse, especially in low-income households and in the developing world. The contribution of these substances to tissue damage and STI transmission, if any, is unknown. - (Health24, February 2011)
Source: Population Council