Table 4 Summary results from cohort studies reporting on arsenic exposure and the risk of bladder cancer
Study [reference] (Table from original publication) | Study locale | Outcome | ICD1 | Arsenic exposure assessment | Exposure [comments] | Outcome measure | Cohort size | Cases | Risk estimate (95% CI) | Covariates assessed |
|---|---|---|---|---|---|---|---|---|---|---|
Chen et al. 1988 [70] (Table Six) | 4 neighbouring townships from Blackfoot disease (BFD) endemic area, Taiwan | Morality 1968-83 | N/A | Group level | Median arsenic content of artesian well and (range): 0.78 ppm (0.35–1.14); in shallow well: 0.04 (0.00-0.30). General population used as reference. 95% CI obtained from IARC 2012 review [23]. | SMR | 871 | 15 | 38.8 (21.7–64.0) | |
Chiou et al. 1995 [32] (Table Four) | 4 neighbouring townships from BFD endemic area, Taiwan | Incidence 1988 (Follow-up period ranged 0.05 to 7.7 years) | N/A | Individual level ‘estimated’ | Cumulative arsenic exposure (mg˙•L-1˙•year): | RR | 2,556 | 29 | age, sex, cigarette smoking | |
0 | 1.0 | |||||||||
0.1–19.9 | 1.57 (0.44–5.55) | |||||||||
> 20 | 3.58 (1.05–12.19) | |||||||||
unknown | 1.25 (0.38–4.12) | |||||||||
[Median arsenic content of artesian well and (range): 0.78 ppm (0.35–1.14); in shallow well: 0.04 (0.00-0.30). Histories of residential address and duration of drinking well water used to derive cumulative exposure.] | ||||||||||
* Tsuda et al.2 1995 [34] (Table Three) | Niigata, Japan | Mortality 1959-92 (Recruitment in 1959, followed until 1992) | Transitional cell carcinoma | Individual level ‘measured’ | Arsenic water concentration (μg˙•L-1): | SMR | 443 | age, smoking habits | ||
< 50 | 254 | 0.00 (0–12.50) | ||||||||
50 – 990 | 76 | 0.00 (0–47.05) | ||||||||
ICD9 188, 189 ICDO histology N/A | ≥ 1,000 | 113 | 31.18 (8.62–91.75) | |||||||
[Arsenic-polluted area. Exposure to be between 1955-59. All 34 wells in the area were sampled and arsenic concentration ranged from non detectable to 3,000 μg˙•L-1).] | ||||||||||
Lewis et al. 19993[40] (Table Four) | Millard County in Utah, USA | Mortality (Recruitment 1900–1945) | N/A | Group level | Cumulative arsenic exposure derived from: low exposure (< 1000 ppb-year); medium (1,000-4,999 ppb-year); high (≥ 5,000 ppb-year): | 4,058 | Individual data on cofactors not available. However, the cohort was assembled from historical membership records of the Church of Jesus Christ of Latter-day Saints (Mormons) which prohibits tobacco use and the consumption of alcohol and caffeine. | |||
SMRmale | – | 0.42 (0.08–1.22) | ||||||||
< 1,000 ppb•year | SMRfemale | – | 0.81 (0.10–2.93) | |||||||
≥ 5,000 ppb•year | SMRmale | – | 0.4 | |||||||
[Residential history combined with local water records used to assess exposure. High variability in exposure estimates in each community with median arsenic concentrations ranging from 14 to 166 ppb. Records of arsenic measurements dating back to 1964.] | SMRfemale | – | 1.18 | |||||||
SMRmale | – | 0.95 | ||||||||
SMRfemale | – | 1.10 | ||||||||
* Chiou et al. 20013[33] (Table Five) | 18 villages in four townships in Lanyang Basin, North-eastern Taiwan | Incidence 1991-1994 (Follow-up period from time of enrollment to Dec.1996) | Urinary organs | Individual level ‘estimated’ | Arsenic water concentration (μg˙•L-1): | RR | 8,102 | age, sex, cigarette smoking, duration of well water drinking | ||
0–10.0 | Urinary organs | 3 | 1.0 | |||||||
ICD9 188, 189 | ||||||||||
10.1–50.0 | 3 | 1.5 (0.3–8.0) | ||||||||
50.1–100.0 | 2 | 2.2 (0.4–13.7) | ||||||||
Transitional cell carcinoma | > 100.0 | 7 | 4.8 (1.2–19.4) | |||||||
Arsenic water concentration (μg˙•L-1); | RR Transitional cell carcinoma | |||||||||
0–10.0 | 1 | 1.0 | ||||||||
ICDO1 8120.2, 8120.3, 8130.3 | 10.1–50.0 | 1 | 1.9 (0.1–32.5) | |||||||
50.1–100.0 | 2 | 8.2 (0.7–99.1) | ||||||||
> 100.0 | 6 | 15.3 (1.7–139.9) | ||||||||
[Arsenic levels in shallow well ranging from < 0.15 to 3,590 μg˙•L-1 and collected from 3,901 well water samples between 1991–94.] | ||||||||||
† Baastrup et al. 2008 [96] (Table Three) | 23 municipalities in Copenhagen & Asrhus areas, Dannemark | Incidence 1993-1997 (Follow-up from enrollment until date of first cancer diagnosis, emigration, death, or Aug. 2003) | N/A | Individual level ‘estimated’ | Cumulated arsenic exposure (5 mg˙): | IRR | 56,378 | 214 | 1.0 (0.98–1.04) | smoking status, smoking duration, smoking intensity, education, occupation |
Time-weighted average exposure (μg˙•L-1): | IRR | 214 | 1.01 (0.93–1.11) | |||||||
[Average arsenic exposure from 0.05 to 25.3 μg˙•L-1, with mean of 1.2 μg˙•L-1. Average arsenic concentrations obtained from 4,954 samples from 2,487 water utilities collected, 1987–2004, with most samples dating 2002–04. Residential history 1970–2003.] | ||||||||||
*†Huang et al. 2008 [53] (Table Two) | 3 villages in Putai Township, in BFD endemic area of southern Taiwan | Incidence 1989 (Average follow-up period of 12 years) | Urothelial carcinoma | Individual level ‘estimated’ | Arsenic water concentration (μg˙•L-1): | RR | 1,078 | age, sex, cigarette smoking, education | ||
0–400 | 1 | 1.0 | ||||||||
ICDO3 M-codes 8120/3, 8230/3 | 401–700 | 14 | 5.2 (0.7–39.8) | |||||||
710–900 | 9 | 6.7 (0.8–53.4) | ||||||||
≥ 900 | 7 | 6.5 (0.8–53.1) | ||||||||
Cumulative arsenic exposure (mg˙•L-1•year): | RR | |||||||||
0 | 0 | – | ||||||||
0.1–11.9 | 2 | 1.0 | ||||||||
12.0–19.9 | 9 | 4.6 (1.0–21.8) | ||||||||
≥ 20.0 | 20 | 7.9 (1.7–37.9) | ||||||||
[Period of arsenic water samples collection not reported. Participants used artesian well water more > 30 years when recruited. Information from interview included history of well-water consumption, residential history, lifestyle factors]. | ||||||||||
*†Chen et al. 20105[60] (Tables One, Two) | Taiwan | Incidence 1991-1994 (Average follow-up period of 11.6 years) | Urothelial carcinoma | Individual level ‘measured’ | Arsenic water concentration (μg˙•L-1): | RR | 8,086 | age, sex, cigarette smoking status, education, alcohol consumption at enrolment, and whether subject started drinking well water from birth | ||
ICDO histology | < 10 | Urothelial carcinoma | 3 | 1.0 | ||||||
N/A | 10–49.9 | 6 | 1.85 (0.45–7.61) | |||||||
Urinary organs | 50–99.9 | 3 | 2.19 (0.43–11.1) | |||||||
ICD9 188, 189, 189.1-189.9 | 100–299.9 | 7 | 5.50 (1.39–21.8) | |||||||
≥ 300 | 10 | 10.8 (2.90–40.3) | ||||||||
unknown | 7 | 4.34 (1.06–17.7) | ||||||||
Cumulative arsenic exposure (μg˙•L-1•year): | ||||||||||
< 400 | RR | 6 | 1.0 | |||||||
400– < 1,000 | Urinary organs | 3 | 1.16 (0.29–4.64) | |||||||
1,000– < 5,000 | 12 | 2.44 (0.91–6.50) | ||||||||
5,000– < 10,000 | 5 | 3.88 (1.18–12.7) | ||||||||
≥ 10,000 | 11 | 7.55 (2.79–20.4) | ||||||||
Unknown | 8 | 2.90 (1.01–8.37) | ||||||||
[Arsenic concentration ranged < 0.15 to > 3,000 μg˙•L-1 and was estimated using 3,901 water samples from residence of participants at time of interview. Other measures of arsenic exposure included, duration of exposure, age starting/ending drinking well water, and cumulative exposure.] | ||||||||||
*†Chung et al. 20136[65] (Table One) | 3 villages in Putai Township, in BFD endemic area of southern Taiwan | Mortality 1996-2010 (Average follow-up period of 17.8 years) | ICD9 188 | SMR based analyses: | Median arsenic content of artesian well (range: 700–930 μg˙•L-1) measured in the early 1960s. | SMRmale | 1,563 | 24 | 2.9 (27.5–63.8) | SMR adjusted for age |
SMRfemale | 19 | 59.4 (35.7–92.7) | ||||||||
Group level | ||||||||||
[Used age-adjusted mortality rate in Taiwan as standard rates.] | ||||||||||
HR based analyses: Individual level ‘estimated’ | Average arsenic concentration in artesian well (μg˙•L-1): | HR | HR adjusted for age, gender, education, smoking habits | |||||||
< 50 | 1 | 1.0 | ||||||||
50–710 | 15 | 4.35 (0.56–33.52) | ||||||||
> 710 | 22 | 7.22 (0.95–55.04) | ||||||||
[Duration of drinking artesian well water and history of residential address obtained from questionnaires. Authors found a significant association with duration of well water drinking.] |