Occupational exposure to toluene and its possible causative role in renal damage development in shoe workers.
OBJECTIVE
An important, although, unprecise number of shoe workers in Leon, Mexico, are in continuous contact with toluene-based glues. The induction of renal glomerular and/or tubular lesions as a result of toluene exposure is still being discussed controversially. Our objective was to evaluate the extent of occupational exposure, assessing urinary o-Cresol excretion as a measure for toluene exposure in a population at risk as compared to a control population. Urinary albumin excretion (UAE) and N-acetyl-beta-D-glucosaminidase (NAG) enzymatic activity were tested to assess renal dysfunction.


METHODS
A cross-sectional study was performed comparing 50 toluene-exposed shoe workers and 25 control subjects. Urinary o-cresol was assessed on first and last day of labor week from exposed subjects. A single urine sample was obtained from control subjects. Urinary Albumin excretion (UAE) and (NAG) activity were examined in 12 h urine samples in all subjects. Urine and serum creatinine were measured to asses renal function.


RESULTS
At the end of the labor week, urinary o-cresol levels were higher in samples obtained from exposed subjects. Albumin excretion was similar in the exposed and control groups. NAG activity was greater in the exposed group compared to control group (median 3.5 U/g creatinine vs 1.9 U/g creatinine, z=2.6, P=0.009). An inverse relationship was found between schooling years and the NAG enzymatic activity for the two studied groups (r= -0.27, P=0.02),


CONCLUSIONS
Our findings support the hypothesis that toluene may be a factor associated with the presence of renal damage in exposed shoe workers. As NAG activity is increased, we believe the lesion initiates in the renal tubular cells.
Instituto Investigaciones Médicas, Universidad de Guanajuato, León, Guanajuato, Mexico.
Ana-Lilia
AL
González-Yebra
Carlos
C
Kornhauser
Kazimierz
K
Wrobel
Elva-Leticia
EL
Pérez-Luque
Katarzina
K
Wrobel
Gloria
G
Barbosa
D000269:Adhesives / Q000009:adverse effects*; D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects; D003408:Cresols / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007221:Industry; D007674:Kidney Diseases / Q000139:chemically induced*; D007677:Kidney Function Tests; D008297:Male; D009784:Occupational Diseases / Q000139:chemically induced; D016273:Occupational Exposure / Q000009:adverse effects*; D012775:Shoes; D012959:Socioeconomic Factors; D014050:Toluene / Q000009:adverse effects*
D000269:Adhesives; D000395:Air Pollutants, Occupational; D003408:Cresols; D014050:Toluene; C025390:creosol