Table 2.
Summary of epidemiological studies on the association of organochlorines and cancer risk among Japanese
| Reference | Study period | Outcome | Design | Study subjects | Exposure assessment | Exposure | Exposure level (median or range among control group) | Category | Odds ratios | 95% confidence interval | P for trend | Confounding factors | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Definition | Age range | Number of subjects | ||||||||||||
| Iwasaki et al. [18] |
Enrolment 1990–1994, follow-up to 2002 |
Breast cancer |
Nested case– control study |
Cases: identified from local hospitals, population-based cancer registries and death certificates, Controls: cohort members matched by age, public health centre area, area, date of blood collection, time of day of blood collection, fasting time at blood collection and menopausal status |
40–69 years old at enrolment | 139 cases and 278 controls | Plasma samples measured by a gas-chromatography isotope-dilution massspectrometry (GC-IDMS) | p,pʹ-DDT (ng/mL) | 0.50 | Quartile 1 | 1 | 0.97 | Adjusted for age at menarche, menopausal status and age at menopause, number of births, age at first birth, height, body mass index, and alcohol consumption | |
| 0.89 | Quartile 2 | 0.65 | (0.32–1.32) | |||||||||||
| 1.36 | Quartile 3 | 0.56 | (0.26–1.22) | |||||||||||
| 2.24 | Quartile 4 | 0.99 | (0.47–2.08) | |||||||||||
| p,pʹ-DDE (ng/mL) | 2.50 | Quartile 1 | 1 | 0.25 | ||||||||||
| 4.83 | Quartile 2 | 1.01 | (0.47–2.19) | |||||||||||
| 7.58 | Quartile 3 | 1.24 | (0.60–2.53) | |||||||||||
| 14.41 | Quartile 4 | 1.48 | (0.70–3.13) | |||||||||||
| β-HCH (ng/mL) | Not detected | Quartile 1 | 1 | 0.34 | ||||||||||
| Not detected | Quartile 2 | 1 | ||||||||||||
| 0.69 | Quartile 3 | 0.84 | (0.45–1.57) | |||||||||||
| 1.38 | Quartile 4 | 0.74 | (0.39–1.39) | |||||||||||
| Itoh et al. [19] | Enrolment 2001–2005 | Breast cancer | Hospital-based case–control | Cases: histopathologically confirmed, Controls: medical check-up examinees matched by age and area of residence | 20–74 years old | 403 cases and 403 controls | Serum samples measured by gas chromatography-isotope-dilution high resolution mass spectrometry (GC-ID-HRMS) | o,pʹ-DDT (ng/g lipid) | 0.90 | Quartile 1 | 1 | 0.48 | Adjusted for total lipid concentration in serum, bodymass index, menopausal status and age at menopause, smoking status, fish consumption, vegetable consumption, family history of breast cancer in a first-degree relative, age at first childbirth, parity, age at menarche, history of breast cancer screening, and history of breast feeding | |
| 1.3 | Quartile 2 | 0.57 | (0.25–1.29) | |||||||||||
| 2.0 | Quartile 3 | 1.13 | (0.53–2.38) | |||||||||||
| 4.1 | Quartile 4 | 0.67 | (0.30–1.52) | |||||||||||
| p,pʹ-DDT (ng/g lipid) | 5.6 | Quartile 1 | 1 | 0.33 | ||||||||||
| 8.5 | Quartile 2 | 0.58 | (0.27–1.25) | |||||||||||
| 12.0 | Quartile 3 | 0.99 | (0.47–2.07) | |||||||||||
| 23.0 | Quartile 4 | 0.58 | (0.27–1.25) | |||||||||||
| p,pʹ-DDE (ng/g lipid) | 160 | Quartile 1 | 1 | 0.46 | ||||||||||
| 300 | Quartile 2 | 0.47 | (0.24–0.92) | |||||||||||
| 490 | Quartile 3 | 0.99 | (0.48–2.02) | |||||||||||
| 1100 | Quartile 4 | 1.02 | (0.46–2.26) | |||||||||||
| β-HCH (ng/g lipid) | 26 | Quartile 1 | 1 | 0.63 | ||||||||||
| 52 | Quartile 2 | 0.81 | (0.39–1.72) | |||||||||||
| 82 | Quartile 3 | 0.72 | (0.31–1.69) | |||||||||||
| 160 | Quartile 4 | 1.04 | (0.43–2.52) | |||||||||||
| Total PCBs (ng/g lipid) | 110 | Quartile 1 | 1 | 0.008 | ||||||||||
| 160 | Quartile 2 | 0.79 | (0.36–1.72) | |||||||||||
| 200 | Quartile 3 | 0.57 | (0.28–1.15) | |||||||||||
| 290 | Quartile 4 | 0.33 | (0.14–0.78) | |||||||||||
| Sawada et al. [20] |
Enrolment 1990–1994, follow-up to 2005 |
Prostate cancer |
Nested case– control study |
Cases: identified from local hospitals, population-based cancer registries and death certificates, Controls: cohort members matched by age, public health centre area, area, date of blood collection, time of day of blood collection, and fasting time at blood collection |
40–69 years old at enrolment | 201 cases and 402 controls | Plasma samples measured by gas chromatography-isotope-dilution high resolution mass spectrometry (GC-ID-HRMS) | o,pʹ-DDT (ng/g lipid) | < 2.5 | Quartile 1 | 1 | 0.61 | Adjusted for smoking status, alcohol intake, marital status, body mass index, and intake of green tea and miso soup | |
| 2.5–4.2 | Quartile 2 | 1.39 | (0.79–2.44) | |||||||||||
| 4.3–7.6 | Quartile 3 | 1.29 | (0.71–2.34) | |||||||||||
| 7.7 | Quartile 4 | 1.04 | (0.54–2.03) | |||||||||||
| p,pʹ-DDT (ng/g lipid) | < 24 | Quartile 1 | 1 | 0.45 | ||||||||||
| 24–40 | Quartile 2 | 1.51 | (0.87–2.63) | |||||||||||
| 41–63 | Quartile 3 | 0.92 | (0.50–1.70) | |||||||||||
| 64 | Quartile 4 | 1.00 | (0.52–1.92) | |||||||||||
| p,pʹ-DDE (ng/g lipid) | < 560 | Quartile 1 | 1 | 0.65 | ||||||||||
| 560–939 | Quartile 2 | 1.00 | (0.60–1.66) | |||||||||||
| 940–1599 | Quartile 3 | 0.89 | (0.52–1.53) | |||||||||||
| 1600 | Quartile 4 | 0.90 | (0.52–1.54) | |||||||||||
| β-HCH (ng/g lipid) | < 200 | Quartile 1 | 1 | 0.05 | ||||||||||
| 200–319 | Quartile 2 | 0.89 | (0.52–1.50) | |||||||||||
| 320–519 | Quartile 3 | 0.85 | (0.50–1.46) | |||||||||||
| 520 | Quartile 4 | 0.56 | (0.30–1.01) | |||||||||||
| Total PCBs (ng/g lipid) | < 319 | Quartile 1 | 1 | 0.90 | ||||||||||
| 319–447 | Quartile 2 | 1.06 | (0.63–1.79) | |||||||||||
| 448–668 | Quartile 3 | 0.84 | (0.49–1.46) | |||||||||||
| 669 | Quartile 4 | 0.97 | (0.51–1.87) | |||||||||||
DDT Dichlorodiphenyltrichloroethane, DDE Dichlorodiphenyldichloroethylene, HCH Hexachlorocyclohexane, PCBs Polychlorinated biphenyls