The Association between Prolonged Occupational Exposure to Paraphenylenediamine (Hair-dye) and Renal Impairment

Introduction: Paraphenylenediamine (PPD) is widely used in hair dyes and cosmetic skin application. PPD intoxication following oral ingestion could be an important cause of ARF in Sudan, Morocco and the Indian Subcontinent. Repeated and prolonged exposure to PPD may also be associated with Chronic Kidney Disease (CKD). Methods: This is a cross-sectional study that covered six conveniently-chosen hairdressing saloons in Khartoum, Sudan. Hairdressers with regular professional exposure to PPD were evaluated for the presence of renal impairment (serum creatinine ≥ 2 mg/dl) and other markers of kidney damage. Results: The study included seventy-two females with a mean age of 40±8 years and a median duration of exposure to PPD of 6 years. Renal impairment, proteinuria and hematuria were observed in 14%, 26.4% and 41.1% of hair dressers, respectively. Hypertension, skin changes and bronchospasm were found in 19.4%, 38.9% and 22% of participants, respectively. Using pure forms of PPD significantly increased the risk of having elevated serum creatinine (OR 5.9; P = 0.02) and proteinuria (OR 9.8; P = 0.002) compared to manufactured forms with lower concentrations. Each additional year of exposure to PPD significantly increased the risk of having elevated serum creatinine (OR 1.3; P = 0.01), proteinuria (OR 1.4; P = 0.001) and hematuria (OR 1.1; P = 0.04). Conclusion: In this group of hairdressers with regular exposure to PPD, we observed high prevalence of renal impairment, proteinuria and hematuria. These findings were significantly associated with the use of pure forms of PPD and longer duration of exposure. Keywords: Chronic Kidney Disease; Hair Dye; Occupational Hazard; Paraphenylenediamine; Nephrotoxicit

Ankyrin is the major oxidised protein in erythrocyte membranes from end-stage renal disease patients on chronic haemodialysis and oxidation is decreased by dialysis and vitamin C supplementation

Chronically haemodialysed end-stage renal disease patients are at high risk of morbidity arising from complications of dialysis, the underlying pathology that has led to renal disease and the complex pathology of chronic kidney disease. Anaemia is commonplace and its origins are multifactorial, involving reduced renal erythropoietin production, accumulation of uremic toxins and an increase in erythrocyte fragility. Oxidative damage is a common risk factor in renal disease and its co-morbidities and is known to cause erythrocyte fragility. Therefore, we have investigated the hypothesis that specific erythrocyte membrane proteins are more oxidised in end-stage renal disease patients and that vitamin C supplementation can ameliorate membrane protein oxidation. Eleven patients and 15 control subjects were recruited to the study. Patients were supplemented with 2 × 500 mg vitamin C per day for 4 weeks. Erythrocyte membrane proteins were prepared pre- and post-vitamin C supplementation for determination of protein oxidation. Total protein carbonyls were reduced by vitamin C supplementation but not by dialysis when investigated by enzyme linked immunosorbent assay. Using a western blot to detect oxidised proteins, one protein band, later identified as containing ankyrin, was found to be oxidised in patients but not controls and was reduced significantly by 60% in all patients after dialysis and by 20% after vitamin C treatment pre-dialysis. Ankyrin oxidation analysis may be useful in a stratified medicines approach as a possible marker to identify requirements for intervention in dialysis patients