﹙一﹚前言
環境化學物質﹙envirnonmental chemicals﹚對於造成野生動物的異常影響在過去的10年早有記錄已經建立,其中賀爾蒙中的雌激素﹙estrogens﹚被認為對內分泌系統具有中止以及改變作用,這些副作用包括誘導卵黃蛋白原﹙vitellogenin induction﹚、雄性會出現雌性生殖器官﹙feminized reproductive organs﹚、降低生殖力﹙reduced fecundity﹚、改變性別﹙change in sex ratio﹚和發育退化﹙developmental degeneration﹚1.2,最受關注3。
﹙二﹚雌激素可能代謝途徑
雌激素﹙estrogens﹚可能被用於人類賀爾蒙的補充、蓄牧助長劑經過廢棄、消化、代謝、排泄其主藥﹙未代謝產物﹚和代謝產物成污染物,分別流向廢水處理廠和大地環境。也會有可能因下大雨將在廢水處理廠的污染物,流向大地。再經過土壤的滲透回到飲用水處理廠。期間很有可能其污染物經過非生物性的轉化﹙Abiotic transformations﹚如光解﹙photolysis﹚、水解﹙hydrolysis﹚、氧化﹙oxidation﹚、還原﹙reduction﹚、錯化﹙complexation﹚和生物性的轉化﹙Biotransformations﹚如細菌分解產生﹙microorganisms﹚以及因經產生吸附﹙sorption﹚的代謝產物﹙transformation product﹚,這些未代謝產物和代謝產物最終匯集到飲用水處理廠,再次回到人類飲用4。
﹙三﹚雌激素對水生環境的影響
天然雌激素:17β-estradiol (E2), estrone (E1), and estriol (E3)以及合成雌激素:17α-ethynylestradiol (EE2), and diethylstilbestrol (DES) 5,這些雌激素的活性可能會干擾到水生環境。即使含量非常小在水中濃度下如:1ηg/L 的E2就會讓雄鳟魚﹙male trout﹚誘導卵黃蛋白原6。4ηg/L 的E2和0.1ηg/L 的EE2 會讓雄日本青將魚﹙Japanese medaka﹚開始變性﹙由精巢變為卵巢﹚7。對整體生態環境有強力的影響。
﹙四﹚結論
雖然近年來環境保護之觀念、一直被強調,但是也發現凡有人類足跡的地域,皆會發現藥物殘留,藥物殘留無所不在的滲透在大地,包括:河川、下水道、農作物等。此現象國內外皆知。惟有確實作好藥物回收工作,監測相關事業廢水,嚴格執行環保法律。期盼你我、事業體、政府共同努力,共創美好環境。
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﹙本文作者為藥學碩士﹚