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#2 Tri(n) Butylphosphate

Potentially toxic to the kidney and nervous system.

Tributyl phosphate is an odorless colorless to yellow liquid. Toxic by ingestion and inhalation.

Tri-n-butyl phosphate, Bu3-P, TBP. Industrial chemical; used as a plasticizer, in hydraulic fluid, as a solvent and extractant for metal ions, and as a heat exchange agent.

Number 1