中国环境科学
中國環境科學
중국배경과학
CHINA ENVIRONMENTAL SCIENCE
2014年
10期
2692-2700
,共9页
徐亚%朱雪梅%刘玉强%能昌信%董路
徐亞%硃雪梅%劉玉彊%能昌信%董路
서아%주설매%류옥강%능창신%동로
模糊-随机%暴露评价%不确定性%风险评价
模糊-隨機%暴露評價%不確定性%風險評價
모호-수궤%폭로평개%불학정성%풍험평개
fuzzy-stochastic%exposure assessment%uncertainties%risk assessment
采用模糊理论描述风险评价过程的模糊不确定性,采用概率理论描述随机不确定性,同时为解决模糊数计算过程复杂的问题,将模糊变量表示成均匀随机变量的函数,用 Monte Carlo 算法模拟模糊变量之间的函数运算,从而实现模糊-随机方法的耦合.为验证该模糊-随机耦合模型的有用性,选取青海某汞化工污染场地进行案例研究,通过与 RBCA 模型比较,验证了该模型的基本精度,且能较好地表征场地参数的不确定性对风险评价结果的影响.案例分析的结果表明:人群主要暴露途径为经口摄入,贡献率为80%左右;正常暴露情形下,该场地的健康风险水平为0.28,风险水平可以接受,最不利情况下的健康风险风险水平为1.28,最不利情况出现的概率小于等于1%;该场地对人群的健康风险随着时间减小,在第6年左右其风险减小至可接受水平,建议无需对场地开展污染治理,只需在污染物高峰段(第1~6年或第6~8年)为居民提供替代水源以截断暴露途径,待场地污染水平自然衰减.
採用模糊理論描述風險評價過程的模糊不確定性,採用概率理論描述隨機不確定性,同時為解決模糊數計算過程複雜的問題,將模糊變量錶示成均勻隨機變量的函數,用 Monte Carlo 算法模擬模糊變量之間的函數運算,從而實現模糊-隨機方法的耦閤.為驗證該模糊-隨機耦閤模型的有用性,選取青海某汞化工汙染場地進行案例研究,通過與 RBCA 模型比較,驗證瞭該模型的基本精度,且能較好地錶徵場地參數的不確定性對風險評價結果的影響.案例分析的結果錶明:人群主要暴露途徑為經口攝入,貢獻率為80%左右;正常暴露情形下,該場地的健康風險水平為0.28,風險水平可以接受,最不利情況下的健康風險風險水平為1.28,最不利情況齣現的概率小于等于1%;該場地對人群的健康風險隨著時間減小,在第6年左右其風險減小至可接受水平,建議無需對場地開展汙染治理,隻需在汙染物高峰段(第1~6年或第6~8年)為居民提供替代水源以截斷暴露途徑,待場地汙染水平自然衰減.
채용모호이론묘술풍험평개과정적모호불학정성,채용개솔이론묘술수궤불학정성,동시위해결모호수계산과정복잡적문제,장모호변량표시성균균수궤변량적함수,용 Monte Carlo 산법모의모호변량지간적함수운산,종이실현모호-수궤방법적우합.위험증해모호-수궤우합모형적유용성,선취청해모홍화공오염장지진행안례연구,통과여 RBCA 모형비교,험증료해모형적기본정도,차능교호지표정장지삼수적불학정성대풍험평개결과적영향.안례분석적결과표명:인군주요폭로도경위경구섭입,공헌솔위80%좌우;정상폭로정형하,해장지적건강풍험수평위0.28,풍험수평가이접수,최불리정황하적건강풍험풍험수평위1.28,최불리정황출현적개솔소우등우1%;해장지대인군적건강풍험수착시간감소,재제6년좌우기풍험감소지가접수수평,건의무수대장지개전오염치리,지수재오염물고봉단(제1~6년혹제6~8년)위거민제공체대수원이절단폭로도경,대장지오염수평자연쇠감.
Risk assessment is associated with uncertainties in nature, and neglect of those uncertain elements in evaluating risk will inevitably lead to difficulty for decision-makers in the stage of risk management and decision-making. Fuzzy theory was used to describe the fuzzy uncertainties, and probability theory was employed to describe the random uncertainties. A coupled fuzzy-stochastic model was built to resolve the problem of complex computation of fuzzy numbers in which fuzzy number are represented with the function of uniform random variables. Monte Carlo method was also used to simulate the computation between fuzzy numbers. One mercury contaminated site located in Qinghai Province was selected as a case to demonstrate the effectiveness and reasonability of this coupled model. The reasonability of this model was verified by comparing simulated results of the widely used RBCA model. The case study indicated that:1) the main exposure pathway was oral intake with a contribution rate of 80%;2) the health risk of this contaminated site was acceptable with non-carcinogenic Hazard Quotient (HQ) of 0.28 under normal exposure condition;under the most unfavorable exposure condition which appearance probability was less than 1%, the health risk was unacceptable with HQ equals to 1.28;3) the health risk would decline in time and reach to an acceptable level after about six years. Therefore, it was suggested that the related responsibility should provide other drinking water resources to eliminate the exposure routine in the period of the first 6 years or the 6-8 years rather than take engineering measurements to remediate this contaminated site.