博士 / 國立臺灣大學 / 農業工程學研究所 / 89 / The purposes of this dissertation is to develop a physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model for arsenic accumulation in aquaculture fish from blackfoot disease (BFD) area, Taiwan. The bioaccumulation of inorganic arsenic (As) in tissues of groundwater aquaculture fish was analyzed. The BFD area is located in the southwest coastal regions of Taiwan in that the aquacultures of the fish located were subjected to As pollution from groundwater. Water and fish (large-scale mullet, Liza macrolepis and tilapia, Oreochomis sp.) samples were collected from the fish farms in the BFD area of Putai, Yichu, Peimen and Hsuehchia, respectively. The field investigation was to analyze fish for assessing the bioaccumulation of As and to estimate the concentration of As in the aquaculture ecosystems. The equilibrium bioconcentration factors (BCFss) were calculated. Total arsenic concentrations of the aquaculture fish target tissues were analyzed. Results show that As concentrations range from 0.98 mg g-1dry mass in muscle tissue to 54.14 mg g-1 in gut tissue. Significant regressions of As in fish (Cf) and in viscera (Cv) against body weight (W) were found , for O. sp. : Cf = 16.801e-0.0038W (R2 = 0.6172, p < 0.05) and Cv = 23.274e-0.004W (R2 = 0.6708, p < 0.05) ; whereas for L. macrolepis : Cf = 83.965e-0.0601W (R2 = 0.7065, p < 0.05) and Cv = 132.5e-0.0666W (R2 = 0.6796, p > 0.05). The BCFss value of As in O. sp. was determined to be 350.28 ± 643.49 mL g-1, wereas in Liza macrolepis was 164.75 ± 298.06 mL g-1. There was no significant difference (F = 1.71, p > 0.05) in As concentrations between O. sp. and L. macrolepis.
The acute toxicity experiment gives the 24- 48- 72- and 96-h LC50 values of 69.06 ± 1.66, 51.52 ± 1.74, 38.44 ± 1.83 and 28.68 ± 1.92 mg mL-1, respectively. The LC50 values obtained from the acute toxicity experiment was incorporated into the Hill model to establish the PD model. A six-compartment PBPK/PD model of the disposition of As in fish key organs (blood, muscle, gill, stomach, gut, liver) was then developed to predict tissue distributions and to assess effect of As concentration in fish.
A comparison between field observations and model predictions shows that the PBPK/PD model was successfully fitted to determine As concentrations in the target tissues (average %errors range from 4.82 %－81.47 %). After exposing 300 d in As contaminated fish ponds, PBPK/PD model simulations indicate that the order of As concentrations accumulation in fish target tissues is gut (12860 ng g-1) > liver (4920 ng g-1) > blood (4740 ng g-1) > stomach (2320 ng g-1) > gill (1470 ng g-1) > muscle (1260 ng g-1); whereas the order of % mortality is gut (9.71 %) > liver (0.737 %) > blood (0.667 %) > stomach (0.092 %) > gill (0.026 %) > muscle (0.017 %).
| Identifer | oai:union.ndltd.org:TW/089NTU00404047 |
| Date | January 2001 |
| Creators | Sher Singh, 沈林琥 |
| Contributors | Chung-Min Liao, 廖中明 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 195 |
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