Aircraft engine oils; BA, basophils; Dermal exposure; EO, eosinophils; G3, grade 3; G3-N, grade 3 in an unused state; G3-U, grade 3 in a used state; G4, grade 4; G4-N, grade 4 in an unused state; G4-U, grade 4 in a used state; HCT, hematocrit; Hematological parameters; Hgb, hemoglobin; IACUC, Institutional Animal Care and Use Committee; LY, lymphocytes; MCH, mean corpuscular hemoglobin; MCHC, mean corpuscular hemoglobin concentration; MCV, mean corpuscular volume; MO, monocytes; MPV, mean platelet volume; NE, neutrophils; NMR, nuclear magnetic resonance; PLT, platelets; RBC, red blood cells; RDW, red blood cell distribution width; Reproductive organs; SDS, safety data sheet; Sprague Dawley rats; TCP, tricresyl phosphate; TIPP, phenol isopropylated phosphate (3:1); TOCP, tri-ortho-cresyl phosphate; TPP, triphenyl phosphate; WBC, white blood cells; WPAFB, Wright-Patterson Air Force Base