摘 要 本研究主因為新竹香山海域所養殖牡蠣容易受到重金屬污染，而客雅溪被認為是造成香山附近海域牡蠣污染的主要來源，因此在本研究中收集了客雅溪91~93年水質監測資料與新竹科學園區放流水數據，連同香山附近海域重金屬銅與砷在海水與底泥中之監測資料進行數據分析，研判斷銅與砷在環境中流布情形，同時在研究的過程中也針對香山海域中海水、底泥與養殖牡蠣中重金屬濃度進行實際採樣分析，計算出所養殖牡蠣對於銅與砷之生物濃縮因子(bioconcentration factor, BCF)，與估算可能的攝取速率常數，並藉上述結果推估可能污染源與牡蠣體內可能累積量。 經由研究的結果顯示，並未發現新竹科學園區所排放之廢水與牡蠣受污染情形有直接相關性，但客雅溪水質和海水與底泥中銅濃度有直接相關性，這顯示可能有其他污染源造成嚴重污染，在客雅溪水質部分則顯示當客雅溪中銅濃度愈高，海水中銅濃度也會愈高；當懸浮固體物含量愈高，海水中銅濃度愈低且底泥中銅含量愈高，而砷與客雅溪水質間，則未發現明顯相關性。對於生物濃縮因子的部分，牡蠣對銅的數值範圍約為104~106，砷則為102~104，此結果高於一般文獻值，牡蠣對於銅與砷之攝取速率常數範圍分別為446~1,066(1/day)與3.21~4.63(1/day)，結果與文獻值接近，因此推測養殖一年的牡蠣體內銅與砷累積量可高達銅512~1,201 mg/kg，砷的累積量則約為2.21~3.97 mg/kg，此高濃度累積量值得相關單位採取適當因應措施。 Abstract The objective of this study was to investigate potential sources of oyster contaminated by copper and arsenic in Sien-San area, Hsin-Chu City. Because most contaminants were regarded as coming from the Keya River, monitoring contaminant data from the river and the content of copper and arsenic in marine and sediment collected from web site and reports, which could indicate the fate of the selected metal in environment. Despite the data mentioned above, in situ sampling and analysis for selected metal in various matrixes including marine, sediment, and oyster were carried out in order to obtain the bioconcentration factor (BCF) and uptake rate constant of the selected metals with regard to oyster. By examining the BCF and uptake rate constant, the accumulative amounts of the metals in oyster can be predicted. The results of heavy metal analysis in various mediums and collected data from literatures indicate that there are no significant relation between contamination of Keya River and wastewater discharge from Science Park in Hsin-Chu City. The copper concentration in marine increases with increasing copper concentration in Keya River and decreases with increasing SS concentration in Keya River. Accordingly, the copper ions in marine and sediment were thought to result from plants near Keya River, but arsenic ions were not. As for the BCF, the ranges of BCF for copper and arsenic were set as104~106 and 102~104, respectively. The obtained BCF values in this study are slight higher than those in literature. The uptake rate constants (1/day) estimated for copper and arsenic are about 446~1066 and 3.21~4.63. Based on the predicted uptake rate constants, the accumulative amounts of heavy metal in oyster within one year can be calculated with which copper is about 512~1201 mg/kg and arsenic is about 2.21~3.97 mg/kg.
