Trifluoroacetic acid is actually more lipid soluble than acetic acid. The octanol-water partition* of TFA is about 3:1 where acetic acid is about 2:3; there may be some sense in using soapy water in washing. Many old-fashioned soaps are slightly alkaline as well. TFA is about as strong, in pK and concentration as a concentrated aqueous acid, but will absorb into the skin far more easily than an acid like 36% hydrochloric. I regard it as more hazardous in this way.

*Howard and Meylan; Handbook of Physical Properties of Organic Chemicals; CRC Lewis; 1997

Does anyone have an idea of why (M)SDS so often recommend “wash gently with soap and plenty of water”? What is the soap supposed to do? My understanding is that soap primarily acts by dissolving grease; dissolving grease releases dirt; water washes away dirt. Is there a significant fat/oil/grease component to a TFA splash? Are we just reading boiler plate washing instructions?

SMK

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From: DCHAS-L Discussion List [mailto:dchas-l**At_Symbol_Here**MED.CORNELL.EDU]On Behalf Of Kim Gates
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Subject: [DCHAS-L] Question on trifluoracetic acid & emergencies