Breast Cancer and Serum Organochlorines: a Prospective Study Among White, Black, and Asian Women

Abstract

Future investigations must consider the biologic mechanisms involved and variations in exposure to chemical pollutants and of breast cancer incidence rates among diverse groups of women.

Serum organochlorines and breast cancer: a case–control study among African-American women

“…It is possible that the serum organochlorine levels measured in the study population are too low to influence breast cancer risk. Our levels of PCBs and DDE, as well as those of African American women in North Carolina collected during the 1990s (16), are substantially lower than those reported by Krieger et al (22), which were measured in the 1960s. However, compared to those measured in Caucasian women from samples taken in the 1990s, our levels and those measured among North Carolina black women are approximately 1.0 and 0.15 μg/g higher for lipidadjusted DDE and PCBs, respectively (16).…”

“…The majority of the earliest case-control studies were null but these also tended to have small sample sizes, did not study a well-defined population or failed to control for breast cancer risk factors that could have confounded the comparison between case patients and controls (10-13). Recent larger case-control studies that more carefully controlled for confounding factors have provided mixed results with some positive findings among subgroups of the populations defined by tumor receptor status but with limited statistical power to evaluate subgroups (14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28). Among the positive studies, one (28) reported a significant difference in DDE between breast cancer case patients and controls, as well as an almost 4-fold increase in risk comparing the highest quintile of DDE to the lowest; however, the values for serum organochlorine levels were not lipid adjusted.…”

“…Explanations proposed include that the expression of various tumor receptor proteins, namely ER, PR, HER2 and p53 may result in effect modification of the exposure-disease relationship in breast cancer (57)(58)(59). Only two previous studies have looked specifically at African-American women, and neither found significant differences in serum levels of DDE or PCBs between case patients and controls (16,22). This study's finding of an interaction between the association between DDE levels and breast cancer risk with ER status is in line with that of Dewailly et al who found significant differences in mean adipose DDE between ER positive case patients and controls (14).…”

“…Several epidemiologic studies since the 1970's have examined the association between breast cancer in women and organochlorines measured either in the serum or adipose tissue. A number of these studies have been null, but others have had mixed results or findings limited to subgroups of the populations studied (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28). While DDT and PCBs were banned in the US in the 1970's, residues of DDT and PCBs continue to be detected in the blood of most Americans as they are persistent in the environment, are known to accumulate in tissue including the fatty tissue of the breast, and have long half lives (29)(30)(31).…”

“…While DDT and PCBs were banned in the US in the 1970's, residues of DDT and PCBs continue to be detected in the blood of most Americans as they are persistent in the environment, are known to accumulate in tissue including the fatty tissue of the breast, and have long half lives (29)(30)(31). Compared with Caucasians, African-Americans have higher levels of serum DDT compounds (32,33); in addition, their PCB levels have been higher than whites in several studies (16,22). Therefore they are potentially at a greater risk of associated adverse health affects.…”