Occupational exposure to silica and end-stage renal disease - reply.
JAMA J Am Med Assoc 1997 Aug; 278(7):547
The authors respond to comments by Wilke (see NIOSHTIC record NIOSH- 00239290) on their article entitled End-Stage Renal Disease among Silica-Exposed Gold Miners: A New Method for Assessing Incidence among Epidemiologic Cohorts (Journal of the American Medical Association, Vol. 277, pages 1219-1223; see NIOSHTIC record NIOSH- 00237303). They agreed with Wilke that the biological basis for the increased risk of end stage renal disease (ESRD) reported in the cohort of silica (14808607) exposed gold miners is unknown. Two different mechanisms of toxicity leading to ESRD may be operating in different patients: direct toxicity or an immunological abnormality. In patients with evidence of immune dysfunction, it is unclear whether the immunologic abnormalities are directly responsible for renal injury or whether they represent a response to the toxic effects of silica. It was noted that the specific characteristics of silica dust exposure may contribute to the variability in the mechanism of silica toxicity. For example, the pathologic potential of silica dust is known to be related to how the dust is produced. Freshly ground silica dusts appear to more cytotoxic in-vitro and more inflammatory in-vivo than aged silica dusts. The authors conclude that further studies are required to clarify the mechanisms involved in silica toxicity.
NIOSH-Author; Kidney-disorders; Silica-dusts; Occupational-exposure; Underground-mining; Mine-workers; Immune-system-disorders
Journal of the American Medical Association