Observations on toxicologically relevant arsenic in urine in adult offspring of families with Balkan Endemic Nephropathy and controls by batch hydride generation atomic absorption spectrometry

Abstract

The aim of this study was to develop a method for the characterization of internal exposure to arsenic, which is thought to play a role in the development of a kidney disease, known as Balkan Endemic Nephropathy, typical for a district in Bulgaria, and to investigate whether the As body burden differs in the offspring versus control individuals. For this case study, an analytical procedure for the determination of toxicologically relevant arsenic (the sum of arsenite, arsenate, monomethylarsonate, and dimethylarsinate) in urine by batch-type hydride generation atomic absorption spectrometry was developed. Optimization experiments for levelling off the sensitivity of inorganic arsenic and its mono-and dimethylated species in dilute HCl-L-cysteine medium were performed. The limit of detection for hydride forming arsenic fraction was 0.5 ng As, i.e. 0.25 mg L À1 in 10 mL of 1 þ 4 v/v diluted urine. The relative standard deviation was typically 1.5-1.8% for aqueous solution and 2-6% for urine samples at 1.0 mg L À1 As. The sample throughput rate was 15 h À1 . No statistical correlation and crosscorrelation between individuals case-control and sex at 95% confidence were found: controls (n ¼ 99), mean 3.5 AE 2.1 (SD), range 0.9-10.4, median 3.0 mg L À1 As and cases (n ¼ 102), mean 3.6 AE 2.2 (SD), range 0.5-11.0, median 3.2 mg L À1 As. On the basis of this study, arsenic can be excluded as a factor involved in BEN development.