Cardiovascular mortality and arsenic (As) exposure by drinking water in Auvergne (France)

Cardiovascular effects (i.e., hypertension, ischemic heart disease and stroke) of arsenic (As) have been studied in countries where As-drinking water levels are high (> 100 μg/L). In France, in 1997, a review of the As level in drinking water has showed that more than 200 000 persons (half living in the Auvergne region) are deserved by water exceeding 10 g μAs / L (i.e., WHO guideline value). In this context, an ecological study is performed in Auvergne (France) to study the spatial and temporal variation of mortality from cardiovascular diseases (codes CIM-9: 390-459) between 1979 and 1999, according to exposure of As-drinking water. Demographic and mortality data are provided respectively by the French National Demographic Institute (INSEE) and the French National Service of Medical Statistics (INSERM - CepiDC). The standardized mortality rate (SMR) are calculated by sex, using the population data of the 1982, 1990 and 1999-census, in each geographical unit of analysis defined as the communes (i.e., smallest French territorial division) by the method of indirect standardization; the Auvergne population has been defined as referring population. As-exposure is obtained by the database of the national health survey of drinking water (SISE-Eaux). Exposure to arsenic is estimated by the average levels of arsenic in water distribution individual units (UDI) of communes. Statistical analyses and geographical representation of data are carried out with the StatEL statistical software and MapInfo geographic information system (GIS); the threshold of significance is p <0.05. Since 1980, cardiovascular sub-mortality is shown in Auvergne in both male and female populations, although significant improvement is highlighted in the communes equipped by medical structures. Moreover, and whatever the studied period has been, trends of sub-mortality are observed more frequently in the female population living in areas deserved with As-drinking water values above the WHO guidelines.