Sulfur, 50µg/g (0.0050 wt%) in Diesel Fuel, 100ml

2,4,4'-Tribromo[13C12]diphenyl ether, 1.2ml x 50ug/ml, nonane

Salts in Crude Oil (Ca, Mg, Na)

N-Nitroso-di-n-butylamine, 100mg