The relationship of daily mortality to suspended particulates in Santa Clara County, 1980-1986.

This paper explores the relationship between daily mortality and suspended particulates in Santa Clara County, CA, for years 1980 to 1986. An association was found between high particulate concentrations and increased mortality. This association persists after adjustment for temperature, relative humidity, year, and seasonality. Contrary to expectation, the magnitude of the particulate effect appears the same or larger than that estimated for London, despite Santa Clara County's cleaner air. The persistence of an effect at these lower particulate concentrations suggests that the particulate variable may be acting as a surrogate for some constituent particles, such as acid aerosols.