....Not sure you will find any specific toxicity data for NaOH-this is from FDA (correct as at August 22nd 2014) -it seems to reflect the general opinion(except for Australia-who I believe have banned NAOH/E534 in food )
§184.1763 Sodium hydroxide.
(a) Sodium hydroxide (NaOH, CAS Reg. No. 1310-73-2) is also known as sodium hydrate, soda lye, caustic soda, white caustic, and lye. The empirical formula is NaOH. Sodium hydroxide is prepared commercially by the electrolysis of sodium chloride solution and also by reacting calcium hydroxide with sodium carbonate.
(b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981), which is incorporated by reference. Copies are available from the National Academy Press, 2101 Constitution Ave. NW., Washington, DC 20418, or available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to:http://www.archives...._locations.html.
© In accordance with §184.1(b)(1), the ingredient is used in food with no limitation other than current good manufacturing practice. The affirmation of this ingredient as generally recognized as safe (GRAS) as a direct human food ingredient is based upon the following current good manufacturing practice conditions of use:
(1) The ingredient is used as a pH control agent as defined in §170.3(o)(23) of this chapter and as a processing aid as defined in §170.3(o)(24) of this chapter.
(2) The ingredient is used in foods at levels not to exceed current good manufacturing practice.
(d) Prior sanctions for this ingredient different from the uses established in this section do not exist or have been waived.
[48 FR 52444, Nov. 18, 1983]