[PopolaTheLabRat]

Hi guys. So 2 days ago, while i was cleaning up after doing acid-base titration and discarding my titration solutions (with few drops of phenolphthalein indicator), the solution poured on my hands while draining it on the sink. I quickly realised that my index finger had a small paper cut that hasn't fully healed yet. Its a small shallow cut that was no larger than 1cm. The wound came in contact with the solution.

The wound didn't irritate and there were no symptoms at all, but out of caution, i rinsed the my entire hands with tap water and soap.

But should i be concerned? Since the solution came into contact with broken skin?

[Borek]

Neither acids nor bases in concentrations used in typical alkalimetry experiments are harmful, and they are not more dangerous than many things using in food preparation. In this case just washing is perfectly enough.

Same goes about most indicators (phenolphthalein included).

[PopolaTheLabRat]

Neither acids nor bases in concentrations used in typical alkalimetry experiments are harmful, and they are not more dangerous than many things using in food preparation. In this case just washing is perfectly enough.

Same goes about most indicators (phenolphthalein included).

I see. Im wondering, what about the carcinogenicity of phenolphthalein? I worry a bit after realising that the phenolphthalein considered a "possible carcinogen to humans"

[Borek]

"Possible" means nothing in this context.

If I were to guess it probably goes like "some aromatic compounds are carcinogenic, so when we see an aromatic compound and we have no hard data on it, we mark it as a »possible carcinogen«, so that nobody sues us".

Also: quite often even trying to collect hard data turns out impossible. People are dying of cancer all the  time, so in every possible group researched some will die too. That means you can never say "none of the ppl researched died of cancer", but any correlation - if it exists - drowns in the noise. Whether that means there is no carcinogenic effect, or it is so low it is undetectable - no way to say. But it also means you are doing yourself a disservice worrying about possible effects, as stress kills much faster and much more often.

[PopolaTheLabRat]

There is hard data of phenolphthalein being carcinogenic. NTP did a 2-year feed study that was published in 1991, where they fed rodents with different doses of phenolphthalein for 2 years. Most of the rodents that were fed phenolphthalein developed cancer.
"https://ntp.niehs.nih.gov/publications/reports/tr/400s/tr465"

Its a class 2B carcinogen (possibly carcinogenic) arcording to the IARC because of this study.

Im just wondering how worried should i be about this carcinogen for this single exposure?

I don't know if it would be a big deal if its just a single expsure like for my case, or its only a big deal if it is chronic exposure like smoking and drinking alcohol.

[Hunter2]

Dont worry, I think there are more dangerous stuff in air and food to get cancer.  1 time a little phenolphtalein is no problem.
In the past phenolpthalein was added  to laxative chocolate.

https://www.sciencedirect.com/topics/medicine-and-dentistry/phenolphthalein