Objectives: Whether low-level exposure to lead may give rise to chronic kidney disease or end-stage renal disease (ESRD) is debated. In this study, we aimed to specifically investigate if low-level occupational exposure to lead was associated with increased incidence of ESRD.
Methods: The incidence of starting renal replacement therapy as a result of ESRD was examined in a cohort of10 303 lead-workers who had controlled blood lead concentrations due to a compulsory occupational health surveillance programme in Sweden during the time period 1977-1990. The ESRD incidence (obtained through register-linkage) among the lead-exposed workers was compared with the age, sex and calendar period-adjusted expected incidence based on data from the Swedish renal registry. Dose-response association was evaluated in external (general population) and internal (within the occupational cohort) comparisons by highest achieved blood lead level.
Results: There were 30 (0.29%) individuals in the cohort who developed ESRD during the median follow-up period of 26.3 years. The standardised incidence ratio (SIR) for ESRD incidence was 0.79 (95% CI 0.54 to 1.13). Among those who achieved the highest blood lead (>41.4 µg/dL), the SIR was 1.01 (0.44 to 1.99). There was no evidence of a dose-response relationship between the maximum achieved blood lead or the cumulative blood lead exposure and ESRD in external or internal comparisons.
Conclusions: This study of workers with documented occupational lead exposures followed for 20 years shows no statistically significant association between lead exposure (following the current occupational recommendations for Sweden) and ESRD.
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