e Never permanent night shifts f Family history of

e Never permanent night shifts. f Family history of breast/prostate cancer. g Among parous women. h Among postmenopausal women.
Table 2
Descriptive characteristics among controls by occupational exposure to alkylphenolic compounds.
Breast cancer
Prostate cancer
Never exposed Ever exposed p-Valueb
Never exposed Ever exposed p-Valueb
Barcelona
Primary
No
Never
Never smoker
Never
Never
Day shifts
No
Not applicable
Not applicable
Never
Not applicable
Nulliparous
Not applicable
Not applicable
Postmenopause
Not applicable
Never
a Percentages do not sum to the total due to missing values. b Chi squared, calculated without missing values. c Row percentage, the rest of percentages in the table are column percentages. d Chi-squared test of difference of exposure by sex. e Expressed as weight (kg)/height2 (m2). f Never permanent night shifts. g Family history of breast/prostate cancer. h Among parous women. i Among postmenopausal women. 394
increased probability of cancer that Anthranilic Acid the unexposed (OR = 1.21; 95% CI = 1.00–1.47). Occupational exposure in other scenarios or to other compounds showed mostly similar non-statistically significant asso-ciations (Fig. 1). In general, we did not observe associations between the different scenarios and specific types of alkylphenolic compounds and prostate cancer (Fig. 1). An exception was the occupational use of cosmetic, hair and personal hygiene products, which was associated with nearly three-fold risk compared to the unexposed (OR = 2.97; 95% CI = 1.15–7.69), although sample size was small (8 controls and 15 cases).
3.4. Sensitivity analyses
Among those unexposed to solvents, estimates were usually above the unity, and the ORs for the association between ever exposure to alkylphenolic compounds and breast cancer (OR = 1.19; 95% CI = 0.97–1.47) was similar to the overall ORs for whole population (Table 3) although it was no longer statistically significant (Supple-mental Table 1). When we considered only those exposures that were frequent and/or of high intensity, conclusions were mostly similar (Supplemental Table 2). Adjusting models for maternal or paternal SES yielded similar conclusions. No significant interactions were detected between BMI, menopausal status or education and ever exposure to alkylphenolic compounds (data not shown). Analyses excluding 138 in
4. Discussion
Using data from a large epidemiologic case-control study, we ob-served a moderate positive association between occupational exposure to alkylphenolic compounds and breast cancer, and in general, no as-sociations with prostate cancer. In support of the hypothesis of an as-sociation between breast cancer and these chemicals, estimates were stronger among those who ever worked frequently exposed and with high intensity of exposure, compared with those exposed to alkylphe-nolic compounds but never with a frequent and high intensity. Within the different scenarios of exposure, the occupational use of domestic tensioactives was positively associated with breast cancer, while other scenarios showed similar, but not statistically significant associations. The type of compound most frequently used among exposed women was nonylphenol ethoxylates, which were positively associated with breast cancer. Overall, no associations were observed for prostate cancer and occupational use of alkylphenolic compounds. However, exposures occurred on 1997 or onwards revealed significant associa-tions, as well as occupational use of cosmetic, hair and personal hygiene products, although based on a small sample size.