Details

Autor(en) / Beteiligte

• Gupta, S.K
• Gupta, R.C
• Seth, A.K
• Gupta, A.B
• Bassin, J.K
• Gupta, A

Titel

Adaptation of cytochrome-[b.sub.5] reductase activity and methaemoglobinaemia in areas with a high nitrate concentration in drinking-water

Ist Teil von

• Bulletin of the World Health Organization, 1999-09, Vol.77 (9), p.749

Ort / Verlag

World Health Organization

Erscheinungsjahr

1999

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• An epidemiological investigation was undertaken in India to assess the prevalence of methaemoglobinaemia in areas with high nitrate concentration in drinking-water and the possible association with an adaptation of cytochrome-[b.sub.5] reductase. Five areas were selected, with average nitrate ion concentrations in drinking-water of 26, 45, 95, 222 and 459 mg/l. These areas were visited and house schedules were prepared in accordance with a statistically designed protocol. A sample of 10% of the total population was selected in each of the areas, matched for age and weight, giving a total of 178 persons in five age groups. For each subject, a detailed history was documented, a medical examination was conducted and blood samples were taken to determine methaemoglobin level and cytochrome-[b.sub.5] reductase activity. Collected data were subjected to statistical analysis to test for a possible relationship between nitrate concentration, cytochrome-[b.sub.5] reductase activity and methaemoglobinaemia. High nitrate concentrations caused methaemoglobinaemia in infants and adults. The reserve of cytochrome-[b.sub.5] reductase activity (i.e. the enzyme activity not currently being used, but which is available when needed; for example, under conditions of increased nitrate ingestion) and its adaptation with increasing water nitrate concentration to reduce methaemoglobin were more pronounced in children and adolescents.