飲用水中顆粒、離子及殘餘鋁對高油飲食小鼠健康影響之研究

Abstract

天然原水經由淨水程序處理後，於水中殘留之顆粒、離子及鋁會在供水上衍生出許多問題，同時也會對環境中諸多生物產生健康上的影響，且考量國內飲食型態逐漸轉為高油飲食，若長期食用下會使生物健康產生問題，進而導致疾病發生。本研究分為兩個部分，第一部分為探討水中殘留顆粒及離子在不同飲食型態下所產生之健康影響，利用小鼠作為試驗物種，於研究中使用不同濾膜(UF膜及RO膜)將自來水中物質分為顆粒及離子，並搭配餵食一般及高油飼料進行暴露實驗，且配合飲用水水質分析以找出影響小鼠健康的可能因素。第二部分為針對自來水中不同殘餘鋁的濃度對小鼠進行健康影響評估，於模擬自來水組成之人工水樣中添加不同濃度鋁進行暴露實驗，分析目標器官(大腦、腎臟、脾臟、肝臟及睪丸)的功能及健康狀況，於最後估算出自來水中殘餘鋁對小鼠之可觀察到有不良影響的最低值(LOAEL)及參考劑量(RfD)。 比較餵食不同油脂含量飼料下搭配飲用三種暴露水樣對小鼠產生的健康影響可得知，一般飼料搭配無顆粒與離子之飲用水及高油飼料搭配飲用自來水對小鼠健康狀況影響較大，會對小鼠之大腦、腎臟、脾臟、肝臟及睪丸等器官造成氧化壓力及發炎反應的產生(p<0.05)，同時易使脂質累積於小鼠體內，而飲用無顆粒之飲用水則對小鼠健康影響較不顯著。無顆粒與離子之飲用水因無任何顆粒及離子存在，推測小鼠長期飲用後會使小鼠體內鈣、鎂及鉀等礦物質或必須微量元素缺乏，進而導致小鼠健康狀況不良；而自來水當中因鋁濃度遠高於其餘兩種暴露水樣，推測飲用自來水同時餵食高油飼料之小鼠則會因高油飲食下鋁的暴露造成健康狀況惡化，而飲用無離子之飲用水則對小鼠較為健康。 另外暴露不同鋁濃度後得到可觀察不良影響的最低值(LOAEL)為5 mg/L (0.914 mg/kg)，而參考劑量(RfD)為0.0091 mg/kg-day，在此濃度下便會對小鼠腎臟、脾臟及肝臟產生影響，若將鋁濃度提高至25 mg/L，則會對大腦、腎臟、脾臟、肝臟及睪丸五種目標器官皆產生健康影響。

Particless, ions and residual aluminum (Al) after water purification processes have raised numerous concerns for the safety of drinking water. Considering dietary habits, the long-term consumption of high-fat foods also possibly causes the negative effects on human health. Our current survey reveals that the utilization of drinking water containing high amount of residual Al accompanying by high-fat dietary habit may simultaneously result in the inflammation effect on some organs in human body. This study aimed to assess the effects of the long-term coupling utilization of drinking water containing particles, ions and different dietary habits (normal and high-fat feeding) on the health of mice. Particularly, our study included two parts. The first part investigated the co-effects of different Al forms (particle and ionic) and different dietary habits on mice, and the second part investigated the effects of different Al concentration. Firstly, tap waters containing Al as feeding water were prepared via two filtration processes, ie, ultrafiltration (UF) and reverse osmosis (RO), which applied to feed the mice. The co-effects of three exposure tap water samples (1) un-treated tap water, (2) tap water after UF, and (3) tap water after RO and different dietary habits (normal and high-fat feeding) on the mice were investigated. Secondly, synthetic tap waters with different Al concentrations were also prepared to survey the various effects of Al on the health of mice. The result has found that the normal-fat feeding coupling with RO filtration water and high-fat feeding with un-treated tap water had negatively greatest impact on the health of mice. Specifically, oxidative stress and inflammation have significantly been observed in the brain, kidney, spleen, liver and testis of tested mice (p<0.05). The negative effects of RO filtration water possibly results from the lack of essential elements, such as calcium, magnesium and potassium and other trace elements. After RO filtration, drinking water without any particles and ions existed. The long-term intake of such water possibly causes stresses on the mice body. In case of un-treated tap water, the stresses may cause by the co-effect of aluminum concentration in tap water and high-fat feeding. This study implies that drinking water after UF filtration has the smallest affects on the health of mice even under high-fat dietary habit. The results of different Al concentration test reveals that the lowest-observed-adverse- effect level (LOAEL) of aluminium was 5 mg / L (0.914 mg/ kg), and the reference dose (RfD) was 0.0091 mg/kg/day. In such exposure dose of Al, kidneys, spleen and liver are mostly affected.