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Although some persistent organic pollutants (POPs) are considered human carcinogens, results from studies evaluating exposures and breast cancer risk have been inconsistent, potentially related to varying ages at exposure. Additionally, few studies evaluated the association between POPs exposure and mammographic breast density (MBD), an intermediate biomarker of breast cancer risk. We carried out a cross-sectional study to investigate associations between serum POPs concentrations and MBD measured in 1998 in female residents of Triana, Alabama, in a predominately African American population with high POPs exposures, particularly to p,p'-DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane). We measured lipid-adjusted serum concentrations (ng/g lipid) of p,p'-DDT and its main metabolite p,p'-DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), polychlorinated biphenyls (PCBs), β-hexachlorocyclohexane (β-HCCH), heptachlor epoxide, oxychlordane, trans -nonachlor, mirex, and aldrin for each woman in our study (n = 210). We also measured two MBD metrics, percent MBD (%MBD) and area of MBD (aMBD). Using adjusted Spearman correlation coefficients (r s) we evaluated correlations between %MBD and aMBD with individual POPs in the overall population and by age group (19–40, 41–54, and 55–91 years) and also estimated adjusted mean measures of MBD with 95% confidence intervals across tertiles of analytes using generalized linear models (GLM). We calculated p- values for multiplicative interaction by age group using GLM. Additional analyses excluded women with current hormone replacement therapy (HRT) use and evaluated early-life exposure (prior to age 18) during the heaviest contamination period in Triana (1947–90). Among all women, we found no correlation between p,p'-DDE and %MBD, but after age stratification and exclusion of HRT users, there was a suggestion of a difference by age group, with younger women having a weak positive correlation (r s = 0.12, p = 0.37) and older women having a weak negative correlation (r s = −0.12, p = 0.43); p interaction = 0.06. In contrast, PCBs were weakly positively correlated with %MBD among all women, with the correlation magnitudes increasing after excluding current HRT users (r s -total PCBs = 0.17, p = 0.03). After age stratification and exclusion of HRT users, correlations for PCBs were higher among younger and middle-age women, with only a handful of these correlations being statistically significant. For β-HCCH, the strongest finding was a negative correlation among older women (r s = −0.26, p = 0.07). Correlations were positive predominantly in the younger age group for heptachlor epoxide (r s = 0.27, p = 0.04), oxychlordane (r s = 0.35, p = 0.006), and trans- nonachlor (r s = 0.37, p = 0.003), and largely null for the middle and older age groups; p interaction range: 0.03–0.05. Similar patterns were found in GLM analyses using tertiles of exposure and aMBD as the metric for MBD. Women exposed during the heaviest chemical contamination period in Triana prior to age 18 had positive correlations between %MBD and PCBs, heptachlor epoxide, mirex, oxychlordane, and trans -nonachlor. In this population, despite high exposures to p,p'-DDT and thus high serum concentrations of its main metabolite, p,p'-DDE, we did not find strong evidence of a positive association with MBD. In fact, there was some evidence of a negative association among older women for p,p'-DDE; a similar pattern was found for β-HCCH. However, younger women with higher serum levels of PCBs, heptachlor epoxide, oxychlordane, and trans -nonachlor, who were likely exposed in early life, had higher MBD. These findings should be replicated in larger studies. • This population had particularly high serum levels of p,p'-DDE. • We did not find strong evidence of a positive association between p,p'-DDE and MBD. • In older women we found reduced MBD with higher p,p'-DDE and β-HCCH. • PCBs and other POPs were positively associated with MBD, mainly in younger women. • Early-life exposures to PCBs and other POPs were positively associated with MBD. [ABSTRACT FROM AUTHOR]

Changes in health care delivery necessitate modification in dermatology training. While the residents at The University of Alabama at Birmingham were planning their 1995-1996 curriculum, several questions regarding the most appropriate allocation of time and resources arose. Interest in other residency curricula prompted the development of a national survey of dermatology residents. Our purpose was to provide comprehensive data regarding the didactic, clinical, surgical, and other aspects of today's U.S. dermatology residency training from the perspective of the residents. It is hoped these data will assist dermatology residency programs with evaluation of their current curricula. A comprehensive 31-question multiplechoice survey was mailed to 631 residents in 70 U.S. dermatology residency programs. Results were tabulated and median values and percentages of responses were obtained. A Wilcoxon rank-sum test, a chi-square analysis, and logistic regression analysis were performed on survey items on the basis of residents' satisfaction with the training program. Two hundred forty-eight responses (39%) were returned with all years of training well represented. Median values and percentages obtained outlined the didactic, clinical, surgical, and other aspects of dermatology residency training. Seventeen percent of residents believed they were not being adequately trained. Satisfaction with training was noted with more didactic faculty involvement, consultations and research, and surgical procedures performed per month. Residents with enriched didactic, clinical, and surgical training experiences are more satisfied with their training programs.