Table 2 Summary of epidemiological studies on the association of organochlorines and cancer risk among Japanese
From: Exposure to environmental chemicals and cancer risk: epidemiological evidence from Japanese studies
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 | |||||||||
| Â | Not detected | Quartile 2 | 1 | Â | Â | |||||||||
|  | 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 | Â | 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) |  | |||||||||