飲用水淨水流程移除全氟碳化合物、藥品暨個人保健用品之效率

Abstract

新興污染物為新認定或是未被認定之污染物，這些物質對於人體健康以及生態環境可能具有相當程度的風險，相關環境流布議題也越來越受重視，特別是在進行水資源再利用時，台灣大部分淨水場進行的傳統淨水過程是否能有效移除這些新興污染物，相關資訊仍非常有限。本研究所關注的新興污染物為全氟碳化合物、鎮痛解熱劑和個人保健用品，探討傳統飲用水淨水流程對它們的移除效率情形。 本研究以長興淨水場原水為基質，添加已知濃度標準品，接著經過前加氯、混凝沉澱、快濾以及後加氯的各淨水單元的實驗室模擬，觀察個別單元對待測物的移除率為何，此外也進行UV反應以觀察待測物光解情形。前處理部分，水樣添加同位素標定內標準品後，調整pH值至3，接著以Atlantic HLB 圓盤型吸附劑（直徑47 mm）搭配SPE-DEX 4790自動化固相萃取器進行萃取，萃取後樣本再經濃縮成體積1 mL，以極致液相層析/串聯式質譜儀（UHPLC-MS/MS）進行分析。 在前加氯單元，鎮痛解熱劑、荷爾蒙及類似作用物以及保存劑類，移除率大多超過50%；前加氯對全氟碳化合物移除效率大致介於20－40%，其中PFHxA（perfluorohexanoic acid）完全無法被移除；混凝沉澱對鎮痛解熱劑中的acetaminophen、acetylsalicylic acid、meclofenamic acid以及保健食品 huperzine A移除率較佳（60－80%），然而對大多數鎮痛解熱劑和個人保健用品而言，混凝沉澱的移除效果大多低於30%；混凝沉澱無法移除PFHxA以及PFDA（perfluorodecanoic acid），而對其他全氟碳化合物移除率範圍在20－80%。快濾對大多數個人保健用品有超過 70% 的移除率；快濾對全氟碳化合物移除效率大致介於70－98%，但是對於PFHxA的移除率較差（低於23%）。後加氯單元對鎮痛解熱劑aminopyrine、 phenazone、荷爾蒙EE2、E2、E3、防曬劑oxybenzone、保健食品 huperzine A以及保存劑ethyl paraben、propyl paraben有較佳的移除效果(超過70%)；後加氯對全氟碳化合物移除效率大致介於20－40%，其中PFHxA則完全無法被移除。經全流程處理過後，除了清潔劑NP移除效果較差（低於30%），其餘個人保健用品經全流程處理移除率大多超過90%。全氟碳化合物經全流程處理過後移除率大多超過90%，而PFHxA移除率則是低於20%。UV反應實驗結果顯示，鎮痛解熱劑、荷爾蒙及類似作用物、保健食品huperzine A以及保存劑較易被光解，在UV反應時間60分鐘內，降解去除率可達100%；荷爾蒙及類似作用物之finasteride、防曬劑、驅蟲劑、興奮劑以及清潔劑經過60分鐘UV反應，仍有20－60%未被移除；UV反應結果顯示全氟碳化合物無法被有效光解。 以各淨水單元對待測物之移除率來看，快濾對個人保健用品以及全氟碳化合物移除效果較優於其他淨水單元，移除率大多超過90%；從全流程處理結果顯示，透過傳統飲用水淨水流程可以移除大多數個人保健用品以及全氟碳化合物。

Emerging contaminants are defined as newly identified or unrecognized pollutants. These substances may cause adverse effects on human health and the ecosystem, and their environment fate has become more concerned, especially on the issue of reused water. In Taiwan, most drinking water treatments utilize conventional processes and the information of elimination of these emerging contaminants is still limited. This study focused on the removal efficiency of the processes on perfluocochemicals and personal care products. Raw water from the upstream (Chin-Tan Weir) of Hsin-Dian Creek was used as the matrix and was spiked two levels of eught perfluocochemicals and 23 personal care products into raw water. Four processes were simulated at laboratory scale to evaluate the removal efficiencies：pre-chlorination, coagulation/sedimentation, rapid filtration, and post-chlorination. Some personal care products contain aromatic structures that may be photolyzed; thus this study also investigated the effect of the UV degradation. Water samples were adjusted to pH 3.0 by formic acid then underwent solid-phase extraction with Atlantic HLB disk. The eluents were concentrated to 1 mL by a SpeedVac concentrator and were analyzed by ultra-high performance liquid chromatography/ tandem mass spectrometry. The removal rate of analgesics, hormones and parabens in the pre-chlorination unit are over 50 %; 20-40% of perfluocochemicals were removed in the pre-chlorination unit and PFHxA (perfluorohexanoic acid) was not removed. The coagulation/sedimentation procedure removed less than 30% of the personal care products, and only had better removal on acetaminophen、acetylsalicylic acid、meclofenamic acid and huperzine A (60-80%). The coagulation/sedimentation procedure took out 20-80% of perfluocochemicals expect for PFHxA and PFDA (perfluorodecanoic acid) (not removed). The rapid filtration step took out over 70% of personal care products; the removal rates on perfluocochemicals ranged from 70 to 98% but was not good on removing of PFHxA ( < 23%). The removal rate in post-chlorination process for aminopyrine, phenazone, EE2, E2, E3, oxybenzone, huperzine A, ethyl paraben and propyl paraben were over 70% but other personal care products had removal rates lower than 70% during the post-chlorination process; most of the perfluocochemicals were removed in 20-40% expect for PFHxA (not removed). The whole procedure removed most of the personal care products (>90%) excluding NP (<30%); perfluocochemicals have removals over 90% expect for PFHxA (< 20%). Analgesics, hormones, parabens and huperzine A can be easily photolyzed in 60 minutes by UV radiation (100%). 20-60% of finasteride, suntan lotions, DEET, caffeine and NP were still left after 60-min UV radiation; perfluocochemicals cannot be effectively photolyzed by UV radiation. The rapid filtration step has the best removals in both personal care products and perfluocochemicals (removals > 90%) and the conventional drinking water treatment can remove most of the personal care products and perfluocochemicals.