Chronic Exposure to Drinking Water Arsenic and Gallbladder Cancer Risk: Preliminary Evidence from Endemic Regions of India
Menée dans 2 Etats indiens auprès de 166 témoins et 214 patients atteints d'un cancer de la vésicule biliaire (âge : 30-69 ans ; 73,4 % de femmes), cette étude analyse l'association entre les niveaux d'arsenic dans les eaux souterraines et le risque de développer la maladie
Résumé en anglais
BACKGROUND: Evidence linking arsenic in drinking water to digestive tract cancers is limited. We evaluated the association between arsenic levels in groundwater and gallbladder cancer (GBC) risk in a case-control study (2019-2021) of long-term residents (≥10years) in two arsenic-impacted and high-GBC risk states of India– Assam and Bihar.
METHODS: We recruited men and women aged 30-69 years from hospitals (73.4% women), with newly diagnosed, biopsy-confirmed GBC (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 GBC risk for tertiles of AwAC (µg/L) in multivariable logistic regression models adjusted for important confounders (Range: zero-448.39; median (IQR): T1-0.45(0.0-1.19); T2-3.75(2.83-7.38); T3-17.6(12.34-20.54)).
RESULTS: We observed a dose-response increase in GBC risk based on AwAC tertiles (OR=2.00 (95% CI: 1.05-3.79) and 2.43 (1.30-4.54), p-trend=0.007). Participants in the highest AwAC tertile consumed more tube-well 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.
CONCLUSIONS: These findings suggest chronic arsenic exposure in drinking water at low-moderate levels may be a potential risk factor for GBC.
IMPACT: Risk factors for GBC, a rare digestive tract cancer, are not fully understood. Data from arsenic-endemic regions of India, with a high incidence of GBC, may offer unique insights. Tackling ‘arsenic pollution’ may help reduce the burden of several health outcomes.
