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Brooks - Rand (BRND) Labartory Methods Select one of the links blelow to display the method descriptions associated with BRND.
Lab Name: Brooks - Rand (BRND) Labartory Method Code 001 Total Mercury in Hair and Certified Standard Tissues For total mercury in hair and certified standard tissues, approximately 30 mg of hair was weighed to the nearest milligram into 18.2 mL teflon vials. 5 mL of 7:3 HNO3 + H2SO4 was added, and the samples digested in sealed containers for 3 h at 70 C. Upon cooling, samples were diluted to the 18.2 mL mark with a 5% solution of 0.2N CrCl in 12 N HC1. For total mercury in blood, 100 uL of homogenized blood was placed into a 7 mL conical teflon vial. 0.9 mL of the acid mixture was added, and the sample digested as above. The final volume was taken to be 1.0 mL. Total mercury was analysed on 25-100 uL aliquots of the digestate, by SnCl2 reduction, purging onto gold coated sand, and quantification by Cold Vapour Atomic Fluorescence Spectrometry (CVAFS). The instrumental Detection limit is about 1 pg Hg. Lab Name: Brooks - Rand (BRND) Labartory Method Code 002 Methylmercury in Hair and Certified Tissues For methylmercury in hair and certified tissues, approximately 30 mg was weighed to the nearest mg into 18.2 mL teflon vials. 10 mL of 25% KOH/methanol was added, and the samples digested in sealed containers for 3 h at 70 C. Upon cooling, the samples were diluted to the 18.2 mL mark with methanol. For blood samples, 50 uL of blood was placed into a 7 mL conical teflon vial, 950 uL of KOH/methanol added., and the samples digested as above. The methylmercury was analysed on 25-100 uL aliquots by aqueous phase ethylation, cryogenic GC separation, and CVAFS detection. |
