PAC Database - Detailed Chemical Data

Chemical Identity
Chemical CAS# UN# Health Code Numbers
Tetrabutyl ammonium phosphate 5574-97-0

Formula Synonyms
Physical Properties
Mol Wt State MP (°C) BP (°C) VP (Hg) VP (°C) SG LEL (ppm)
PAC Values
PAC Values (Original Units: mg/m3)
12 130 790
Converted PAC Values (ppm)
0.86 9.4 57
Technical Basis
A review of the limited sources did not identify exposure or toxicity data for this chemical compound. The toxicities of two similar chemicals were also investigated: 1) tetrabutylammonium hexafluorophosphate (CASRN: 3109-63-5) and 2) tetrabutylammonium chloride hydrate (CASRN: 1112-67-0). A summary of GHS hazard statements and safety data sheets for the chemical of interest indicates low-to-mid-level hazards (GHS Categories 2A, 3 and 4) for eye, dermal, and oral exposure, indicating at a minimum an HHR=1. Both similar chemicals have SDS and European Chemical Agency (ECHA) which indicated mid-level hazards
During investigation, available health hazard ratings, specifically GHS classifications and NFPA, were further examined. First, investigating GHS classifications and the United Nations Economic Commission for Europe (UNECE) label elements for acute toxicity (Table 3.1.3), the exposure hazards for the chemical of interest were rated between GHS Categories 4 and 5, as indicated by the ‘warning’ statement and accompany hazard codes (refer to Table 3.1.1, GHS Rev.9, 2021; pg. 123). Of the similar chemicals, both support a GHS Category 4 across oral/inhalation exposures. When TEELs were estimated from these GHS hazard categories, using the lower limits of corresponding Acute Toxicity Estimates (ATEs, Table 3.1.3) the range of potential TEEL-3 values were between 220-1100 mg/m3 (oral LD50, inhalation dust, inhalation vapor). Next, reviewing the NFPA ratings for the chemical of interest and similar chemicals, all were determined to have HHR = 2 in safety data sheets. Considering these analyses, it was determined that an assumed HHR=2 is consistent with both GHS and NFPA health hazard ratings, and it was selected as the TEEL-3 basis (Section 3.4.5). TEEL-2 and TEEL-1 values were derived according to Table 3.5.
• TEEL-1 = TEEL-2/11
• TEEL-2 = TEEL-3/6
• TEEL-3 = Estimated from HHR=2 (rat oral LD50, 4,000 mg/kg)
This review generated TEEL values that are more conservative than those published in Rev. 29A. In Rev. 29A, the basis of the TEEL-3 was a HHR=1 (40,000 mg/kg), however the current review utilized a HHR=2, considering comparability to the GHS results and conservatism.
GHS hazard classifications: National Center for Biotechnology Information (2023). PubChem Compound Summary for CID 2735142, Tetrabutylammonium dihydrogen phosphate.
Summary of GHS classifications:
Tetrabutylammonium chloride SDS:
Tetrabutylammonium phosphate SDS:
Tetra-n-butylammonium hexafluorophosphate SDS:
The United Nations Economic Commission for Europe (UNECE). (2021, September 14). Globally Harmonized System of Classification and Labelling of Chemicals (GHS Rev. 9, 2021).
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