Bladder cancer, chemical carcinogens

Carcinogenic agents include chemicals in the environment, such as aniline and benzene, which are associated with the development of bladder cancer and leukemia, respectively. Environmental factors, such as excessive sun exposure, also may result in cancer. Viruses, including the human papilloma virus and hepatitis B, maybe associated with the development of cancer. Some of the chemotherapy agents cause secondary cancers after therapy has been completed. Numerous factors may contribute to the development of cancer. 

An increased risk of death from bladder cancer (33 vs. 22.7 expected) was reported in 40,000 rubber and cable workers who had mixed exposures to many rubber additives, including PBNA, but not to known carcinogens. In contrast to this study, no significant increases in overall or site-specific cancer was detected in a cohort of 2410 rubber chemical manufacturing workers, who were employed at a factory in north Wales, United Kingdom, between 1955 and 1984. ... 

Zack and Gaffey (1983) reported the mortality status of 884 white men employed for at least one year between 1955 and 1977 by a chemical plant in Nitro, WV, USA, involved in the production of 2,4,5-trichlorophenol and 2,4,5-T. 4-Aminobiphenyl, a human bladder carcinogen (see lARC, 1982), was produced from 1941 to 1952 in this plant. There were nine cases of bladder cancer, with 0.91 expected deaths from cancer other than of the bladder were not in excess. One case of liposarcoma was reported among workers assigned to 2,4,5-T operations. Zack and Suskind (1980) reported cancer outcomes of a cohort of 121 males involved in a 1949 accident at the same plant. Followup revealed nine cancer deaths between 1949 and 1978, with 9.0 expected. Three of these were lymphatic or haematopoietic in origin (0.9 expected p = 0.047]), and one was a primary dermal fibrous histiocytoma (0.15 expected). 

Everyone who works with organic chemicals should be aware that a number of arenamines are carcinogens. The most dangerous examples (see Figure 23-8) are known to induce human bladder cancer. These chemicals were used widely in the chemical industry (mostly in azo dye manufacture) long before they were... 

DOT CLASSIFICATION 6.1 Label KEEP AWAY FROM FOOD SAFETY PROFILE Confirmed carcinogen with experimental tumorigenic data. Along with p-naphthylamine and benzidine, it has been incriminated as a cause of urinary bladder cancer. Poison by subcutaneous and intraperitoneal routes. Moderately toxic by ingestion. Mutation data reported. Combustible when exposed to heat or flame. Incompatible with nitrous acid. To fight fire, use dry chemical, CO2, mist, spray. When heated to decomposition it emits toxic fumes of NOx. See also 2-NAPHTHYLAMINE and AROMATIC AMINES. 

Bladder stone formation can lead to bladder cancer in rats and mice, thus making it difficult to be certain whether a chemical that leads to bladder stone formation and turnorigenesis is or is not a true animal and/or human carcinogen. 

Chemical carcinogenesis emerged as an established field of scientific enquiry after carcinogenic constituents in coal tar were identified by Japanese workers in 1915, and British workers isolated and identified coal-tar 3,4-benzo[a]pyrene as a carcinogen. Wignall (1929) reported the prevalence of bladder cancer among workers exposed to 8 and 10a (studies on 10b, 10c and lOd were not reported) and 1-naphthylamine (ll)24. Unlike... 

Urinary bladder cancer in humans has been associated with exposure to chemicals since the observation by Rehn in 1895 of an increased incidence of bladder cancer in aniline dye workers in Germany (Cohen 1998 Cohen et al. 2000 Johansson and Cohen 1997). As a result of extensive research during the past century, numerous chemicals and mixtures have been identified as causative factors for human bladder cancer, most notably cigarette smoking, which accounts for approximately one-half of the bladder cancer cases in the United States (Cohen et al. 2000 Johansson and Cohen 1997). Most of the chemicals that have been identified as human bladder carcinogens documented by the International Agency for Research on Cancer (lARC) are DNA reactive chemicals, many of which are aromatic amines, such as... 

Public concern has focused on the possible carcinogenic effects of drugs and other chemicals. Long-term chronic toxicity studies in a variety of species have been started in the hope of minimizing potential risk of cancer in man. However, the results of such studies are difficult, sometimes impossible, to interpret. Yet their economic impact can be enormous, as shown by the withdrawal of cyclamates when bladder cancer was observed in a limited number of rodents. Inevitably drugs will be affected too already the safety of certain oral contraceptives has been questioned because of possible carcinogenic effects in the breasts of dogs after extended use. 

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