New insight into solvent-related end-stage renal disease: occupations, products and types of solvents at risk.

It has been shown that all-solvent exposure is associated with the progression of primary glomerulonephritis to end-stage renal disease (ESRD), but little is known about the type of solvents that are high risk. The aim of this study was to investigate the role of solvents by occupation, product and type.Using a retrospective cohort design, the authors studied 269 patients with non-end-stage and biopsy-proven primary glomerulonephritis diagnosed between 1994 and 2001 in Paris and its suburbs. Two industrial hygienists evaluated patients' exposures from lifetime occupational histories collected by interview from 2002-4, and using a list of the 30 most common solvents. The studied outcome was ESRD, defined as glomerular filtration rate <15 ml/mn/1.73 m(2) or dialysis. It was recorded during a mean follow-up of five years. Cox models were used to estimate adjusted hazard ratios (HR) of ESRD related to exposures.Eighteen per cent of the patients had ever been exposed to solvents. Those with the highest risk of progression to ESRD were exposed machinery fitters and machine assemblers (HR 4.7, 95% CI 1.2 to 17.4) and plumbers/welders (HR 4.2, 95% CI 1.3 to 13.6), as compared to never exposed patients, as well as those who ever handled printing inks and petroleum products (HR 12.6 (95% CI 1.7 to 94.9) and 3.2 (95% CI 1.4 to 7.2), respectively). Among solvents, the highest risks were found for: toluene/xylene (HR 5.1, 95% CI 1.8 to 14.8), gasoline, fuel and gas-oil (HR 8.6, 95% CI 2.7 to 27.4), and ketones (HR 13.3, 95% CI 1.4 to 123.5).This study highlights the potential nephrotoxicity of several solvents. Intervention to promote screening for proteinuria in exposed workers may prevent the progression of glomerulonephritis to ESRD.