Does 10% bleach solution damage silicone or not?

June 21, 2019 7:20 PM

Soaking in 10% bleach solution is a very common recommendation for sanitizing silicone sex toys, but silicone menstrual cup manufacturers all seem to say not to use bleach to clean them. What's the deal - does 10% bleach solution damage silicone or not? I'm hoping someone with a materials science background can shed light on this.

My hypotheses for this discrepancy:
1) Maybe something about the composition of the silicone is different (most silicone sex toys are far firmer than menstrual cups, though both are often described as "medical-grade"silicone.)
2) Menstrual cups are usually made by and marketed to people who are more crunchy and more likely to find the idea of bleach objectionable/people generally have more panic about STIs than Toxic Shock Syndrome, maybe this influences the recommendations for cleaning sex toys vs cups?

[I am aware that one can boil cups to sterilize them and also that some people don't think you need to sterilize them but am not looking for discussion about those things, thanks.]

posted by needs more cowbell to Science & Nature (9 answers total)

I had always thought this was because there were concerns about residual bleach (potentially) doing things to your insides, not to the menstrual cups.
posted by jessamyn at 7:28 PM on June 21, 2019 [5 favorites]

According to this chart, which shows up on many rubber and chemical websites, it's not known if bleach harms silicone. Scroll down for "bleach solution."
posted by wryly at 7:32 PM on June 21, 2019

Response by poster: I thought about the residual bleach issue, but if that's the case it would seem striking that that doesn't appear to factor into advice about cleaning sex toys at all, even with things that people might use for extended amounts of time, like buttplugs.
posted by needs more cowbell at 8:05 PM on June 21, 2019

In the U.S. the vast majority of sex toys are sold as “novelty items” and are not held to safety standards in the way that you might expect. Menstrual cups are considered medical devices and are held to a higher standard. The menstrual cup company is legally obligated to be concerned about what their product does to your body. The sex toy company is not.
posted by Secret Sparrow at 8:53 PM on June 21, 2019 [11 favorites]

I have had a silicone menstrual cup for over ten years and I soak it in peroxide overnight after my period is over and then wash it with gentle liquid soap. I used to boil it. I’ve never had any issues.
posted by amapolaroja at 10:48 PM on June 21, 2019

I’m not “crunchy” but I don’t feel comfortable with bleach inside my vagina even though I know it would be trace amounts buy the time my period rolled around again.
posted by amapolaroja at 10:55 PM on June 21, 2019

Anecdata!
I have bleached my Fleurcup with a stronger solution that that (it may have been close to 25 or 30%) and the cup is fine and so am I. I've been using that same cup for 10 years now. No issues of any kind.
Of course you'll want to rinse it very well afterwards, but that's a given.

Mind you, the bleach did not actually remove the discolouration from the cup. Peroxide does, and so does sunlight.
posted by Too-Ticky at 2:18 AM on June 22, 2019 [1 favorite]

Can’t speak to the bleach piece but wanted to suggest an alternative- I use the sterilising tablets for baby bottles for my cup
posted by koahiatamadl at 2:23 AM on June 22, 2019 [1 favorite]

Bleach (sodium hypochlorite) degrades [scripps.edu] very rapidly, especially 10% bleach.

"liquid bleach starts as salt water and degrades into salt water."
posted by porpoise at 2:07 PM on June 22, 2019 [3 favorites]