Department of Environmental and Occupational Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Sci Total Environ. 2010 Feb 15;408(6):1271-5. doi: 10.1016/j.scitotenv.2009.12.036. Epub 2010 Jan 8.
Hazardous waste sites are major environmental concerns, but few studies have quantified their expected utility loss on health.
To evaluate the health impact of groundwater pollution by an electronics manufacturing factory, we conducted a health risk assessment based on expected utility loss from liver cancer.
Based on measurements of major pollutants, we estimated the likelihood of developing liver cancer after exposure to groundwater contamination. All patients with liver cancer between 1990 and 2005 in the Taiwan Cancer Registry were followed through 2007 using the National Mortality Registry to obtain survival function. Quality of life was assessed with two cross-sectional surveys, one employing the standard gamble method, and the other using the EQ-5D instrument. Quality-adjusted life expectancy (QALE) was estimated by multiplying the utility values with survival function under the unit of quality-adjusted life year (QALY). The difference of QALE between the cancer cohort and the age- and gender-matched reference population was calculated to represent the utility loss due to liver cancer.
A total of 94,144 patients with liver cancer were identified. The average utility loss to development of liver cancer was 17.5 QALYs. Based on toxicological approach, we estimated that groundwater pollution caused 1.7 extra cases of liver cancer, with an overall loss of 29.8 QALYs. Based on epidemiological approach, the expected annual excess number of liver cancer would be 3.65, which would have been accumulated through the years, had the pollution not mitigated.
We demonstrated a practical approach for comparative health risk assessment using QALY as the common unit. This approach can be used for policy decisions based on possible health risks.
危险废物场地是主要的环境关注点，但很少有研究量化其对健康的预期效用损失。
为了评估一家电子制造工厂造成的地下水污染对健康的影响，我们根据肝癌的预期效用损失进行了健康风险评估。
基于主要污染物的测量值，我们估计了接触地下水污染后患肝癌的可能性。通过国家死亡率登记处，对 1990 年至 2005 年间在台湾癌症登记处登记的所有肝癌患者进行了随访，直到 2007 年，以获得生存函数。使用两个横断面调查评估生活质量，一个采用标准博弈法，另一个采用 EQ-5D 工具。通过将效用值乘以质量调整生命年（QALY）的生存函数来估计质量调整生命期望（QALE）。癌症队列与年龄和性别匹配的参考人群之间的 QALE 差异被计算出来，以代表肝癌导致的效用损失。
共确定了 94144 例肝癌患者。发展为肝癌的平均效用损失为 17.5 QALYs。根据毒理学方法，我们估计地下水污染导致了 1.7 例额外的肝癌病例，总损失为 29.8 QALYs。根据流行病学方法，预计每年会有 3.65 例肝癌病例会额外增加，如果污染没有得到缓解，这些病例将逐年积累。
我们展示了一种使用 QALY 作为共同单位进行比较健康风险评估的实用方法。这种方法可用于基于可能健康风险的政策决策。
