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Brooks - Rand (BRND) Labartory Methods

Select one of the links blelow to display the method descriptions associated with BRND.

Method Code

Method Title

001 Total Mercury in Hair and Certified Standard Tissues
002 Methylmercury in Hair and Certified Tissues

 

 

 

 

 

 

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.

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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.

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