工業廢水或都市污水處理廠排放水中,通常含有許多化學物質,其中有些對水中生物具有突變性,致癌性,生殖毒性或其他慢毒性;而有些在高濃度時,則具有急毒性甚至造成生物死亡。以傳統之化學分析方法檢測,是無法表示其毒性,也無法得知其對水體所造成的傷害,經由生物毒性試驗才能實際推估放流水進入承受水體所可能造成之生態衝擊或對人類之危害,故建立完整之生物監測系統為管制毒物進入水體之一大利器,也更容易掌握污染來源的特性。
我們計劃使用Microtox™來進行測試,進行檢測水之急毒性,測試水樣包括生活污水,人工溼地進放流水。這些水樣可能含有微量的毒性,須用水生生物毒性試驗來測試。檢測結果可發現進流水樣普遍存在微量的生物毒性,但經處理後之放流水均無生物毒性反應,可知處理廠有明顯的減毒成效。而且Microtox™操作使用簡單且快速,所以,已成為快速廢水毒性測試之典型使用方法之一。
水生生物毒性試驗亦可測試其他物質之毒性,包括垃圾滲出水、污泥、底泥、土壤等可能內含毒性物質之介質,國外使用標準化之生物監測方法已行有多年,但可能並不適用於國內環境,因此建立本土性之生物測試方法,使能成為末來訂定排放水“毒性標準”之依據,以保護水生環境,實屬當務之需。 An effluent toxicity can not be simply determined by traditional chemical basis technique. Toxicity has to be determined by toxicity test using living organisms, then estimation can be made to find out the possible impacts of an effluent to the receiving water. To establish biomonitoring system is necessary to control toxic substances releasing to natural water system.
Microtox assay will be used to determine acute and/or chronic toxicity of constructed wetlenad and municipal wastewater treatment plant effluents.
Aquatic toxicity tests can also be applied to determine toxicity of landfill leachate, sludge, contaminated soil or sediment. Conducting toxicity tests has been required for issuing discharge permits at several developed countries; however established testing methods may not be appropriate for us. Since implementation of such legislation will be in near future in Taiwan, it is necessary to set up our own toxicity testing programs.