An estimation of the health impact of groundwater pollution caused by dumping of chlorinated solvents

摘要

Background: Hazardous waste sites are major environmental concerns, but few studies have quantified theirrnexpected utility loss on health.rnObjectives: To evaluate the health impact of groundwater pollution by an electronics manufacturing factory,rnwe conducted a health risk assessment based on expected utility loss from liver cancer.rnMethods: Based on measurements of major pollutants, we estimated the likelihood of developing liver cancerrnafter exposure to groundwater contamination. All patients with liver cancer between 1990 and 2005 in thernTaiwan Cancer Registry were followed through 2007 using the National Mortality Registry to obtain survivalrnfunction. Quality of life was assessed with two cross-sectional surveys, one employing the standard gamblernmethod, and the other using the EQ-5D instrument. Quality-adjusted life expectancy (QALE) was estimatedrnby multiplying the utility values with survival function under the unit of quality-adjusted life year (QALY).rnThe difference of QALE between the cancer cohort and the age- and gender-matched reference populationrnwas calculated to represent the utility loss due to liver cancer.rnResults: A total of 94,144 patients with liver cancer were identified. The average utility loss to development ofrnliver cancer was 17.5 QALYs. Based on toxicological approach, we estimated that groundwater pollutionrncaused 1.7 extra cases of liver cancer, with an overall loss of 29.8 QALYs. Based on epidemiological approach,rnthe expected annual excess number of liver cancer would be 3.65, which would have been accumulatedrnthrough the years, had the pollution not mitigated.rnConclusions: We demonstrated a practical approach for comparative health risk assessment using QALY asrnthe common unit. This approach can be used for policy decisions based on possible health risks.