Chronic Exposure to Drinking Water Arsenic and Gallbladder Cancer Risk: Preliminary Evidence from Endemic Regions of India

• Published in: Cancer epidemiology, biomarkers & prevention Vol. 32; no. 3; pp. 406 - 414
• Main Authors: Shridhar, Krithiga, Krishnatreya, Manigreeva, Sarkar, Soumyajit, Kumar, Ranjit, Kondal, Dimple, Kuriakose, Steena, Rs, Vinutha, Singh, Amulya K, Kataki, Amal Chandra, Ghosh, Ashok, Mukherjee, Abhijit, Prabhakaran, D, Mondal, Debapriya, Prabhakaran, Poornima, Dhillon, Preet K
• Format: Journal Article
• Language: English
• Published: United States 06-03-2023
• Subjects: Arsenic; Case-Control Studies; Drinking Water - analysis; Environmental Exposure; Female; Gallbladder Neoplasms; Humans; India - epidemiology; Male; Water Pollutants, Chemical; India
• ISSN: 1055-9965; 1538-7755
• DOI: 10.1158/1055-9965.EPI-22-0926

Evidence linking arsenic in drinking water to digestive tract cancers is limited. We evaluated the association between arsenic levels in groundwater and gallbladder cancer risk in a case-control study (2019-2021) of long-term residents (≥10years) in two arsenic-impacted and high gallbladder cancer risk states of India-Assam and Bihar.
We recruited men and women aged 30 to 69 years from hospitals (73.4% women), with newly diagnosed, biopsy-confirmed gallbladder cancer (N = 214) and unrelated controls frequency-matched for 5-year age, sex, and state (N = 166). Long-term residential history, lifestyle factors, family history, socio-demographics, and physical measurements were collected. Average-weighted arsenic concentration (AwAC) was extrapolated from district-level groundwater monitoring data (2017-2018) and residential history. We evaluated gallbladder cancer risk for tertiles of AwAC (μg/L) in multivariable logistic regression models adjusted for important confounders [Range: 0-448.39; median (interquartile range), T1-0.45 (0.0-1.19); T2-3.75 (2.83-7.38); T3-17.6 (12.34-20.54)].
We observed a dose-response increase in gallbladder cancer risk based on AwAC tertiles [OR = 2.00 (95% confidence interval, 1.05-3.79) and 2.43 (1.30-4.54); Ptrend = 0.007]. Participants in the highest AwAC tertile consumed more tubewell water (67.7% vs. 27.9%) and reported more sediments (37.9% vs. 18.7%) with unsatisfactory color, odor, and taste (49.2% vs. 25.0%) than those in the lowest tertile.
These findings suggest chronic arsenic exposure in drinking water at low-moderate levels may be a potential risk factor for gallbladder cancer.
Risk factors for gallbladder cancer, a lethal digestive tract cancer, are not fully understood. Data from arsenic-endemic regions of India, with a high incidence of gallbladder cancer, may offer unique insights. Tackling 'arsenic pollution' may help reduce the burden of several health outcomes.