Table 5.
Study [Ref #] | Study Design | Sample Size, # Cases | Study Period | Study Population, Location | Chemical Exposure(s) | Maternal Outcome(s) | Result |
---|---|---|---|---|---|---|---|
[157] | Nested Case-control. | N=483, 250 cases, 233 controls (frequency-matched). | 1996–2001. | Participation in Danish National Birth Cohort (DNBC) in Denmark. | Measured plasma levels of 16 PFAS: PFOS, PFOA, PFNA, PFHxS, PFOSA, PFBS, PFHpS, PFDS, and PFOSA), PFPeA, PFHxA, PFHpA, PFUnA, PFDoA, PFTrA, and PFTeA; twice in 1st and 2nd trimesters. | Maternal Breast Cancer (MBC). |
PFOS and Maternal BC: Adjusted RR=0.99 (95% CI: 0.98–1.01). When modeled as five categories: Adjusted RR=1.51 (0.81–2.71), 1.51 (0.82–2.84), 1.13 (0.59–2.04), and 0.90 (0.47–1.70) for women in the 2nd, 3rd, 4th, and 5th exposure quintiles compared to women in the lowest exposure quintile. PFOA and Maternal BC: Adjusted RR=1.00 (95% CI: 0.90–1.11). Categorical results were similar. PFNA and Maternal BC: Adjusted RR=0.76 (95% CI: 0.30–1.94); Categorical results were similar. PFHxS and Maternal BC: Adjusted RR=0.66 (0.47–0.94). When modeled as five categories: Adjusted RR=0.64 (0.34–1.18), 0.70 (0.38–1.29), 0.38 (0.20–0.70), and 0.61 (0.33–1.12) for women in the 2nd, 3rd, 4th, and 5th exposure quintiles compared to women in the lowest exposure quintile. PFOSA and Maternal BC: Adjusted RR=1.04 (0.99–1.08). When modeled as five categories: Adjusted RR=1.38 (0.75–2.52), 0.91 (0.49–1.66), 1.11 (0.60–2.05), and 1.89 (1.01–3.54) for women in the 2nd, 3rd, 4th, and 5th exposure quintiles compared to women in the lowest exposure quintile. sumPFSA and Maternal BC: Adjusted RR=1.00 (0.99–1.01). Results were similar when exposure was modeled categorically and for other summary exposure metrics. |
[159] | Nested Case-control. | N=258, 129 cases, 129 controls, (matched on birth year). | 1959–1967. | Participation in Child Health and Development Studies and residence in Oakland, CA, USA. | Measured serum levels of p,p′-DDT, o,p′-DDT, and p,p′-DDE in 3rd trimester or within 1–3 days of delivery. | Maternal Breast Cancer (MBC). |
Model with all compounds p,p′-DDT and MBC: Adjusted OR=1.9 (95% CI: 0.9–4.1, p-value=0.09) and 2.9 (95% CI: 1.1–8.0, p-value=0.04) for women in the 2nd and 3rd exposure tertiles compared to women in the lowest exposure tertile. p,p′-DDE and MBC: Adjusted OR=1.3 (95% CI: 0.6–2.7, p-value=0.48) and 1.0 (95% CI: 0.4–2.4, p-value=0.92) for women in the 2nd and 3rd exposure tertiles compared to women in the lowest exposure tertile. o,p′-DDT and MBC: Adjusted OR=0.5 (95% CI: 0.3–1.0, p-value=0.06) and 0.4 (95% CI: 0.2–0.8, p-value=0.02) for women in the 2nd and 3rd exposure tertiles compared to women in the lowest exposure tertile. Model with all compounds p,p′-DDT and MBC: Adjusted OR=2.5 (95% CI: 1.0–6.3, p-value=0.05) and 5.2 (95% CI: 1.4–19.1, p-value=0.01). p,p′-DDE and MBC: Adjusted OR=1.5 (95% CI: 0.6–3.4, p-value=0.34) and 0.9 (95% CI: 0.3–3.0, p-value=0.90) for women in the 2nd and 3rd exposure tertiles compared to women in the lowest exposure tertile. o,p′-DDT and MBC: Adjusted OR=0.5 (95% CI: 0.2–1.2, p-value=0.13) and 0.3 (95% CI: 0.1–0.7, p-value=0.01) for women in the 2nd and 3rd exposure tertiles compared to women in the lowest exposure tertile. |
[160] | Nested Case-Control. | N=224, 112 cases, 112 controls (matched on birth year). | 1959–1967. | Participation in Child Health and Development Studies and residence in Oakland, CA, USA. | Measured serum levels of 16 PCBs: Estrogenic (101, 187, 201); Non-ortho (66, 74, 105, 118, 156, 167, 138, 170); and Di-ortho (99, 153, 180, 183, 203, and [203/167 + 187] in 3rd trimester or within 1–3 days of delivery. | Maternal Breast Cancer (MBC). |
PCB-167 and MBC: Adjusted OR=1.09 (95% CI: 0.48–2.47), 0.70 (95% CI: 0.27–1.78), and 0.24 (95% CI: 0.07–0.79) for women in the 2nd, 3rd, and 4th exposure quartiles compared to women in the lowest exposure quartile (p-trend <0.04). PCB-187 and MBC: Adjusted OR=0.94 (95% CI: 0.41–2.17), 0.92 (95% CI: 0.36–2.38), and 0.35 (95% CI: 0.11–1.14) for women in the 2nd, 3rd, and 4th exposure quartiles compared to women in the lowest exposure quartile (p-trend <0.02). PCB-203 and MBC: Adjusted OR=1.21 (95% CI: 0.46–3.18), 2.89 (95% CI: 0.98–8.55), and 6.34 (95% CI: 1.85–21.73) for women in the 2nd, 3rd, and 4th exposure quartiles compared to women in the lowest exposure quartile (p-trend <0.001). |
CI = Confidence Interval; DDE = Dichlorodiphenyldichloroethylene; DDT = Dichlorodiphenyltricloroethane; Di-2-ethylhexyl phthalate metabolites (ΣDEHP = MEHHP, MECPP, MEOHP, and MEHP); HR = Hazard Ratio; IQR = Interquartile range; OR = Odds Ratio; OCP = Organochlorine Pesticide; PFAS = Perfluoroalkyl substances; PFDeA = Perfluorodecanoic acid; PFHxS = Perfluorohexane sulfonate; PFNA = Perfluorononanoic acid; PFOSA = Perfluorooctane sulfonamide; PFOS = Perfluorooctane sulfonic acid; PFOA = Perfluorooctanoic acid; PFUA = Perfluoroundecanoic acid; PBPK = Physiologically-based pharmacokinetic; PBDE = Polybrominated diphenyl ether; PCB = Polychlorinated biphenyl; PCDD = Polychlorinated dibenzo-p-dioxins. PCDF = Polychlorinated dibenzofurans. RR = Relative Risk; SD = Standard Deviation.