Cancer incidence among refinery and petrochemical employees in Louisiana, 1983-1999.
OBJECTIVE
The purpose of this study is to determine the incidence of cancer among employees at two petrochemical facilities in south Louisiana, and to compare their cancer rates to those of the general population of south Louisiana.


METHODS
Records on 4639 active and former employees and retirees from the two plants were linked to the Louisiana Tumor Registry (LTR) database by LTR staff to ascertain incident cases of cancer. Standardized incidence ratios (SIRs) were then calculated using the south Louisiana population as the comparison and adjusted for age, race, and time period.


RESULTS
There was a significant 16% deficit of overall cancer cases for males in this cohort (SIR=0.84; 95% CI, 0.74-0.95). The only significantly elevated SIR in males was for cancer of the bone and joint (SIR=6.89; 95% CI, 1.42-20.1). This result was based on three non-fatal cases of bone cancer with different histologies, occurring in different parts of the body. These cases worked in different units of one plant. Significant deficits were seen for lung cancer, non-Hodgkin's lymphoma, and cancer of the oral cavity and pharynx. Cancer incidence among 719 female employees was non-significantly increased (SIR=1.24; 95% CI, 0.81-1.82). Breast cancer accounts for the excess (SIR=1.46; 95% CI, 0.73-2.61). Seventy percent of the breast cancer cases worked in an office setting.


CONCLUSIONS
This study found little evidence of any association between cancer incidence and employment at these two petrochemical facilities. The increased incidence of bone cancer is unlikely to be due to occupational exposures. The non-significant excess of breast cancer may be due to early detection or other important unmeasured confounders, such as certain reproductive factors.
Tsai
Shan P
SP
Shell Oil Company, Shell Health Services, Houston, TX 77252-2463, USA. shan.tsai@shell.com
Chen
Vivien W
VW
Fox
Erin E
EE
Wendt
Judy K
JK
Cheng Wu
Xiao
X
Foster
Delia E
DE
Fraser
Alistair E
AE
D000328:Adult; D000368:Aged; D019992:Databases as Topic; D019652:Extraction and Processing Industry; D005260:Female; D006801:Humans; D015994:Incidence; D008145:Louisiana / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000139:chemically induced / Q000145:classification / Q000453:epidemiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D010578:Petroleum / Q000633:toxicity*; D011159:Population Surveillance; D012042:Registries; D012307:Risk Factors
D010578:Petroleum