Epidemiologic studies of cancer risk

Hagmar L, Welinder H, Linden K, AtteweU R, Osterman-Golkar S, Tornqvist M. An epidemiological study of cancer risk among workers exposed to ethylene oxide using hemoglobin adducts to validate environmental exposure assessments. Int Arch Occup Environ Health 1991 63(4) 271-7. 

Considering its relatively long history of widespread use, it is remarkable that epidemiological studies of cancer risk focused on DDT exposure are almost non-existent. Ditraglia et al (61) studied mortality in workers from four organochlorine pesticide manufacturing plants, one of which had solely manufactured DDT since 1947. Cohorts were defined as all workers who had been employed for at least six months prior to 1965 and vital status was ascertained up to 1976. For the DDT plant a total of 6 cancer deaths were found leading to the calculation of an SMR of... 

The wear products of MOM joint articulahon are transported systemically and are manifested in elevated chromium and cobalt levels in a patient s serum and urine, raising the potential risk for carcinogenesis (Jacobs et al. 1996, Jacobs et al. 1998, Jacobs et al. 1999). However, epidemiological studies of cancer risk in patients with MOM remain inconclusive, because of the relatively small... 

The wear products of MOM joint articulation are transported systemically and are manifested in elevated chromium and cobalt levels in a patient s serum and urine, raising the pKJtential risk for carcinogenesis [36, 69, 70]. However, epidemiological studies of cancer risk in patients with MOM remain inconclusive, due to the relatively small patient populations evaluated, the Scandinavian basis of the studies, and the typically rare incidence of the disease [35, 72]. There have also been reports of metal hypersensitivity associated with the implantation of MOM pros-theses, but the incidence of this complication is reported to be extremely rare [73]. Hypersensitivity may manifest itself in the form of an allergic response on the patient s skin however, there is no accepted clinical test to reliably test a patent s sensitivity to metals [74]. It remains unclear whether metal hypersensitivity is a contributing factor to implant performance or survivorship. 

Besides age, the development of colorectal cancer appears to be caused by variety of dietary or environmental factors, comor-bid disease states, and genetic susceptibility to the disease. Table 88-1 lists well-known risk factors for developing colon cancer. Epidemiologic studies of worldwide incidence of colorectal... 

In an epidemiological study of 1345 workers potentially exposed to acrylonitrile and followed for 10 or more years there was a greater than expected incidence of lung cancer (8 obs. vs. 4.4 exp.)." A trend toward increased risks of cancer of all sites was also observed with increased duration of exposure and with higher severity of exposure. However, in a follow-up of this cohort through 1983 the only statisti-... 

Wei Q, Cheng L, Amos Cl et al. Repair of tobaeeo eareinogen-indueed DNA adduets and lung eaneer risk a molecular epidemiologic study. JNatl Cancer Inst 2000 92 1764-1772. 

A meta-analysis of epidemiological studies of ovarian cancer showed a summary estimated relative risk of 0.64 for ever-use of combined oral contraceptives, implying a 36% reduction in ovarian cancer risk (130). This protective effect increased with increasing duration of oral contraceptive use and continued for at least 10 years after discontinuation. Although most of the oral contraceptives reported in these studies were older, higher-dose formulations, the Cancer and Steroid Hormone (CASH) study included users of tablets containing ethinylestradiol 35 pg or less, and this subgroup of women had a reduced risk of ovarian cancer (115). 

A number of case studies and epidemiological studies of occupationally-exposed workers indicate that inhalation of BCME or CME containing BCME is associated with increased risk of lung cancer (Figueroa et al. 1973 Thiess et al. 1973 Sakabe 1973 Albert et al. 1975 Weiss and Boucot 1975 DeFonso and Kelton 1976 Lemen et al. 

EPA has used cancer risk data from human epidemiological studies to derive risk factors associated with oral exposure to benzene. Oral dose levels associated with specific carcinogenic risks have been extrapolated the risk value of 2.7x 10"2 for lifetime inhalation exposure to 1 ppm was converted to a slope factor of 2.9/10"2 for oral exposure of 1 mg/kg/day, assuming identical levels of absorption of benzene following both routes of exposure. Using the method described by EPA (IRIS 1996), the drinking water levels associated with individual upper-bound estimates of 10"4, 10"5, 10"6, and 10"7 have been calculated to be lxlO 1, lxlO"2, lxlO"3, and lxlO"4 mg/L, respectively, which are equivalent to dose levels of 3x 10"3,... 

Since there are no human studies in which ingestion of a known amount of asbestos can be associated with a clear increase in gastrointestinal cancer risk, NAS (1983) extrapolated data on gastrointestinal risk from epidemiological studies of workers exposed to asbestos by inhalation. These calculations indicated that lifetime ingestion of 1.1x10 TEM fibers/liter of water corresponded to an excess gastrointestinal cancer risk of 10" (NAS 1983). 

It was already known in 1987 that foods that provide large amounts of retinol increase the risk of cancer of the esophagus (92,93), and in an epidemiological study the increased risk of cancer associated with the use of cigarettes and alcohol was enhanced by the ingestion of foods containing retinol (94). 

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