D5-threo-Chloramphenicol, 100 µg/ml, Acetone, 1m

4-n-Octylphenol, 1000µg/mL in MeOH, 1ml

Chlorthiophos, 100 µg/ml, Acetonitrile, 5ml

Sulfur Calibration Mixtures: Di-n-butyl sulfide in Light White Oil (less than 20mg/kg S) Unit : 10mL screw-capped bottle Light White Mineral Oil Heavy White Mineral Oil (20 cSt at 40°C) (70 cSt at 40°C)