A study by the Population Council (Begay 2011) has found that every one of a panel of 41 commercially-available sexual lubricants for sale in the USA damaged human rectal and colonic cells in the test tube and compromised the integrity of the single-cell layer that forms the surface of the rectum.
In contrast Carraguard, a gel formerly tried as an experimental microbicide, did not damage cells.
Unexpectedly, the investigators found that four of the lubricants not only damaged the rectal lining cells but appeared actively to increase HIV replication in the cell cultures.
They found that this activity was caused by polyquaternium-15, a commonly-used cosmetic ingredient, which has the property of facilitating HIV’s attachment to cells.
The study, whose original findings were presented at the Microbicides 2010 Conference last year (Begay 2010), complements the results of two other studies presented at that conference. The first (Russo) tested six popular lubricants and found that four stripped cells off the rectal epithelium (surface membrane). The second (Gorbach) found that men and women who took part in a rectal microbicide study and who used lubricants for anal sex were three times more likely to be diagnosed with gonorrhoea, chlamydia or syphilis than people who used no lube.
For the current survey Othell Begay and colleagues from the Population Council tested a panel of 41 commonly-used lubricants. They tested their cytotoxic (cell-killing) activity in two different ways and, by culturing them with HIV-infected cells, tested whether they inhibited or enhanced viral replication. They used the ratio of their cytotoxic and antiviral properties to calculate a “therapeutic index” (TI) which predicted whether they might have any useful HIV-inhibiting potential in real-life situations.
The researchers compared results from the 41 commercially-available lubes with Carraguard, as detailed above, and also with medical saline solution and Gynol II, a spermicide cream already known to be cytotoxic, as it contains nonoxynol-9, a compound which has been known for ten years to damage cells and make users more vulnerable to HIV.
They found that cells treated with all the lubricants were damaged. A cell assay called TEER (transepithelial electrical resistance) gauges cell integrity by testing their resistance to electric current – whole cells transmit electricity less easily. The researchers found that the TEER value for cells exposed to the lubricants had dropped by 60% within two hours, as it did for cells exposed to Gynol II, whereas it remained steady for cells exposed to Carraguard and saline.
The researchers found only one lubricant with mild anti-HIV activity – the vaginal moisturiser Replens. However the therapeutic index for Replens was under 100 compared with a TI of over 3500 for Carraguard – and Carraguard failed when tested as an HIV-preventing microbicide.
Unexpectedly, the researchers found that one brand of lubricant – Astroglide – appeared actively to enhance HIV replication in cells.
Astroglide has previously been found to inhibit HIV in the test tube to some extent, not enhance it. This paradox can be explained by the fact that, like nonoxynol-9, some lubricant ingredients destroy viruses by dissolving their containing membrane – but do the same thing to cell membranes, and thus have a net harmful effect.
The four (out of six) Astroglide lubricants that appeared to increase viral replication were the only ones containing a compound called polyquaternium-15 which, when tested, was found to be the cause.
In the Russo paper presented last year it was theorised that the cytotoxic properties of lubricants might be due to their being hyperosmolar. This means they contain more sugars and salts than the body’s natural fluids. When hyperosmolar fluids come into contact with cells they cause cells to secrete water and dry up.
Most of the lubricants tests in this study were hyperosmolar. However four where hypo-osmolar, meaning they contained less sugar and salt than body fluids, and one was iso-osmolar, meaning it contained the same balance as body fluids, and none of these were any less toxic. Replens, the least toxic lubricant, was also the most acid, and it is known that vaginal acidity help to protect against HIV transmission.
What does this mean for users of lubricants? These are still preliminary results and much more research is needed before detailed recommendations can be made.
It is important to emphasise that the lubricants tested were all water-based. Water-based ‘lubes’ were initially recommended for use in safer sex because they do not weaken condoms whereas oil-based ones cause them to burst. Since it is the condom that is protecting users from HIV rather than the lube, condom users should still be encouraged to use water-based lubes because condoms are also more likely to break, and trauma to the rectal lining occur, with no lube.
However for people who for one reason or another do not use condoms, water-based lubes may not the safest ones to use. A good compromise are the silicone-based lubricants, which do not appear to damage cells and are also safe with condoms.
References
Begay O et al. Identification of personal lubricants that can cause rectal epithelial cell damage and enhance HIV-1 replication in vitro. AIDS Research and Human Retroviruses, early online edition. February 2011. The study may be viewed online here.
Begay O et al. Preliminary evaluation of toxicity and antiviral properties of personal lubricants. 2010 International Microbicides Conference, Pittsburgh. Abstract no. 129. 2010.
Russo J et al. (presenter Dezzutti C) Safety and anti-HIV activity of over-the-counter lubricant gels. 2010 International Microbicides Conference, Pittsburgh, abstract 347, 2010.
Gorbach PM et al. Rectal lubricant use and risk for rectal STI. 2010 International Microbicides Conference, Pittsburgh, abstract 348, 2010.
This article was first published by NAM/Aidsmap.com and is republished with permission.
The International Rectal Microbicide Advocates (IRMA) – a global network of advocates, scientists, policy makers and funders from six continents working together to advance a robust rectal microbicide research and development agenda – issued an advisory "Safety of lubricants for rectal use: A fact sheet for HIV educators and advocates" (Last updated 13 October 2010) that states:
Based on current evidence:
- More research is urgently needed to explore if there is a link between lube use and acquiring HIV and/or rectal STIs.
- It is unclear whether any particular type or brand of lube might increase, decrease or have no effect on acquiring HIV and/or rectal STIs.
- Using male or female condoms is still considered the best way to prevent acquiring HIV and STIs during AI (anal intercourse). In addition, the use of condom-compatible lubes has been associated with a decreased risk of condoms breaking or slipping.
- It is not possible at this time to recommend for or against using lubes if having AI without condoms.
- Lube use on its own is not a proven method of HIV or STI prevention.
| What do the current research and findings mean to consumers/lube users?
While it may be too soon to say definitively, the latest research on lube safety indicates that most water-based lubes may all cause some degree of tissue damage, which in turn leads to a higher risk of anal STIs and HIV infection. This risk has not been found with silicon-based formulas, which are not hyper-osmolar. [Osmolarity is a measure of the concentration of the soluble components—or solutes—present in a solution. Products can be iso-osmolar, hypo-osmolar or hyperosmolar. Iso-osmolar products have the same osmolarity as normal cells. Hypo-osmolar products tend to make cells swell up with water, which can lead to cells bursting. Hyperosmolar products have a higher concentration of solutes than normal human cells. Therefore, when in contact with the cells of the rectum or vagina, they tend to “suck” away water from inside cells, making them shrink in size. Both hypo- and hyperosmolar products could potentially increase the risk of acquiring HIV and STIs because of their abrasive effect on the lining inside the rectum, but this assumption requires further research. Studies10, 11, 12 have found that many water-based lubes are hyperosmolar, which may explain why these products tend to show greater damage to cells. -- Safety of lubricants for rectal use: Questions & Answers for HIV educators and advocates (IRMA)] Furthermore, there is now evidence that there are specific ingredients which may specifically enhance HIV replication in vitro, and others which show an increased risk for HSV (herpes simplex virus) infection in mice. IRMA acknowledges much more research is needed, but if you want to be absolutely safe, these are some conclusions you can come to based on the available evidence: There is growing evidence that some formulations of water-based lubricants may be unsafe to use, and may be associated with a higher risk of acquiring HIV and/or rectal STIs. The mechanism of for this has not been determined, but one theory is that water-based lubricants that are hyper-osmolar may cause tissue damage in the rectal lining. Evidence is also emerging that specific ingredients used in many popular water-based formulas may be of particular concern, enhancing HIV-replication in vitro, or increasing the risk for HSV-1 infection in mice. The same studies have not found silicone-based lubes to be associated with these safety concerns. While using condoms with a latex-compatible lubricant is still considered the best way to prevent acquiring HIV and STis during anal intercourse, the early evidence suggests: • Silicon-based lubricants may be safer than water-based formulas, and should be preferred especially when condoms are not used (ie barebacking). • Avoid any products with the following ingredients: polyquarternium (found in some formulations of Astroglide), EDTA or GML (glycerol monolaurate). Reference Begay O et al. Identification of personal lubricants that can cause rectal epithelial cell damage and enhance HIV-1 replication in vitro. AIDS Research and Human Retroviruses, early online edition. February 2011. The study may be viewed online here. |
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@12 that's not what the article say: no link has been made yet betwen lube use and HIV infection. More research is needed.
For more info there is a factsheet available here
http://rectalmicrobicides.org/materials.php
or simply read the 5 bullet-points summary above.
also Aston and Demi called and they need our billionaire hot boy's money rasing help for stamping out sexual slavery, so us hot gay polo players gonna raise a heap of cash for this cause, Real Men Don't Pay Girls (or Boys), I love those two dearly and us capable, smart successful gay and straight men gonna help them
we tired of the same old bullshit about free condoms and lube cause its not working
sex is overrated, go ride some horses this weekend
in other news, my son's new golf teacher is a hottie- gay and really super cute and capable, all the gay dads are trying to get their kids in his golf classes, you should see us all swoon when he is teaching our kids
But this whole report is (I think) totally unwarranted in an Asian context where already paranoia runs deep. There is nothing conclusive that comes out of this research that can be applied in practice... but they wait till near the end of the article to tell you that.
The experiments were done in vitro and that doesnt necessarily mean the same situations apply in recto
Add to that the fact that the lining of the rectum is constantly being eroded by the passage of feces and more so with hi fibre feces ( which is advisable) and you begin to wonder what all the hysteria is about
This is precisely the reason why I've decided that from now on I'll only have sex with my right hand! Well OK, I'll do it with my left hand when my right hand is out of town on a business trip. ;-)
Yes folks breathing can be dangerous for you too but I don't see people stop breathing because of it, all of this doesn't mean don't have sex, I think some of the above opinions are a bit extreme and feed into that scare tactic mentality.
I generally like the silicon-based lubes, such as the aforementioned Wet Platinum®, which is widely available and in sizes up to 1/2 GALLON! lolz
But if I may be allowed to whine here: Silicon lubes leave super-slippery spots all over the place -- they're obviously not water-soluble so you'll have to change your sheets/steering-wheel-cover/burka/whatever after each passionate lovemaking session.
Second, anti-HIV organisations should stop distributing complimentary sachets of water-based lub for its anti-HIV campaigns. Instead, silicone-based lub should be distributed. A short message explaining why silicone-based lub is adopted should be included on the sachets. Additionally, as a service to those who want to purchase personal bottles of silicone-based lub, the addresses of local sellers of such products should also be advertised on the mentioned posters and websites.
To avoid confusion, these 2 messages should also be included: (1) water-based lub IF used with condoms is still preferred over unprotected sex & protected sex without any water-based lub.; (2) oil-based lub should NEVER be used because it breaks condoms.
I think that for those who do have a choice they should choose a silicone-based lub. As for those who don't have the luxury of obtaining silicone-based lub, continuing to use a water-based lub with condom is still an effective means of protection against HIV. Even though water-based lub may damage some tissues on the rectum, the extra lubrication provided by it reduces the chances of tear and bleeding, which poses an even higher risk of HIV transmission than mere slight tissue damage. Also, the physical barrier provided by the condom should greatly reduce the chances of HIV transmission. As such, in the absence of silicone-based lub, we should continue to use water-based lub with condom as what conventional anti-HIV campaigns advocate.
if catching a disease is your main concern and is more important than the pleasure of anal sex, then you jolly well should just stay home, order the tenga sex toys online from tengatango.com and wank off to it.
many variations to choose from and guess what, no risk whatsoever.
Ha!
Eros (original)
From this article the recommendation is for safety reasons but in general it is the best for pleasure.
Better than other silicon based ones I have tried. Online ordering works cheapest for me.
But seriously, folks: If you're buying proper-sized name-brand condoms that haven't expired, you store them sealed in their original airtight package at an appropriate temperature, and you're using enough latex-friendly lube, it should be essentially impossible to tear them.
From what I've read, a condom is more likely to slip off due to the downsizing that can occur following ejaculatory nirvana than to tear or break.
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