A UNIQUE METABOLISM OF INORGANIC ARSENIC IN NATIVE ANDEAN WOMEN

Citation
M. Vahter et al., A UNIQUE METABOLISM OF INORGANIC ARSENIC IN NATIVE ANDEAN WOMEN, European journal of pharmacology. Environmental toxicology and pharmacology section, 293(4), 1995, pp. 455-462
Citations number
44
Categorie Soggetti
Pharmacology & Pharmacy",Toxicology
ISSN journal
09266917
Volume
293
Issue
4
Year of publication
1995
Pages
455 - 462
Database
ISI
SICI code
0926-6917(1995)293:4<455:AUMOIA>2.0.ZU;2-F
Abstract
The metabolism of inorganic arsenic (As) in native women in four Andea n villages in north-western Argentina with elevated levels of As in th e drinking water (2.5, 14, 31, and 200 mu g/l, respectively) has been investigated. Collected foods contained 9-427 mu g As/kg wet weight, w ith the highest concentrations in soup. Total As concentrations in blo od were markedly elevated (median 7.6 mu g/l) only in the village with the highest concentration in the drinking water. Group median concent rations of metabolites of inorganic As (inorganic As, methylarsonic ac id (MMA) and dimethylarsinic acid (DMA)) in the urine varied between 1 4 and 256 mu g/l. Urinary concentrations of total As were only slightl y higher (18-258 mu g/l), indicating that inorganic As was the main fo rm of As ingested. In contrast to all other populations studied so far , arsenic was excreted in the urine mainly as inorganic As and DMA. Th ere was very little MMA in the urine (overall median 2.2%, range 0.0-1 1%), which should be compared to 10-20% of the urinary arsenic in all other populations studied. This may indicate the existence of genetic polymorphism in the control of the methyltransferase activity involved in the methylation of As. Furthermore, the percentage of DMA in the u rine was significantly higher in the village with 200 mu g As/l in the water, indicating an induction of the formation of DMA. Such an effec t has not been observed in other studies on human subjects with elevat ed exposure to arsenic.