RESUMEN
OBJECTIVE: To determine whether there is an ongoing risk of developing bladder cancer in a previously studied cohort of workers exposed to both benzidine and dichlorobenzidine or dichlorobenzidine only in the last benzidine manufacturing plant in the USA. METHODS: Workers (n=488) were identified from the quarterly 941 forms the employer was required to submit to the Social Security Administration from 1960 to 1977. Exposures were assigned based on dates worked and known benzidine/dichlorobenzidine production schedules. Incidence, vital status and cause of death were determined through 2014. Analyses were restricted to white men. RESULTS: Bladder cancer incidence and mortality were significantly increased (25 incident cases, standardised incidence ratio (SIR) 2.19, 95% CI 1.42 to 3.23, and 5 deaths, standardised mortality ratio (SMR) 3.79, 95% CI 1.23 to 8.84). There were significant increases in incidence and mortality in those exposed to both benzidine and dichlorobenzidine (SIR 3.11, 95% CI 1.97 to 4.67, SMR 4.10, 95% CI 1.12 to 10.50), but not among workers exposed to dichlorobenzidine only (two incident cases, SIR 0.89, 95% CI 0.11 to 3.23 and one death, SMR 2.90, 95% CI 0.07 to 16.15). Bladder cancer incidence and mortality were increased in individuals with >20 years since last exposure with >5 years worked (six observed, SIR 5.94, 95% CI 2.18 to 12.92 and two deaths, SMR 7.93, 95% CI 0.96 to 28.65). CONCLUSIONS: Incidence and mortality due to bladder cancer increased among workers exposed to benzidine but not among workers exposed only to dichlorobenzidine. The risk of incidence and death from bladder cancer remain elevated more than 20 years after last exposure to benzidine in those who worked >5 years.
Asunto(s)
Bencidinas/toxicidad , Industria Química , Enfermedades Profesionales/inducido químicamente , Neoplasias de la Vejiga Urinaria/inducido químicamente , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/mortalidad , Exposición Profesional/efectos adversos , Factores de Riesgo , Neoplasias de la Vejiga Urinaria/epidemiología , Neoplasias de la Vejiga Urinaria/mortalidadRESUMEN
BACKGROUND: Silica has been associated with end stage kidney disease and kidney dysfunction. METHODS: Calculated glomerular filtration rate, history of kidney disease or chronic dialysis, elevated serum creatinine, and stages of chronic kidney disease among silicotics identified in Michigan's Silicosis Surveillance System from 1987 to 2009 were reviewed to determine the prevalence of kidney disease in confirmed cases of silicosis. RESULTS: Twenty-four percent of 1,072 silicotics had a measure of kidney dysfunction (32.3% if diabetes or hypertension present vs. 20.2% if not). Sixty-nine percent of silicotics had Stage I or greater chronic kidney dysfunction versus 38.8% of the U.S. general population ≥60 years. No association was found between kidney function and measures of silica exposure. CONCLUSIONS: Individuals with silicosis have an increased prevalence of kidney disease. More work to define the pathological changes associated with silica exposure is needed to understand the cause of silica's adverse effect on the kidney.