【作者】 杨慧赞；

【导师】 潘鲁青；

【作者基本信息】 中国海洋大学 ， 水产养殖， 2008， 硕士

【摘要】 近年来,随着海上石油和轮船运输业的发展以及工业、生活污水的大量排放,海洋环境中多环芳烃化合物(polycyclic aromatic hydrocarbon, PAHs)的污染日益加重,16种PAHs已经成为海洋环境中必须监测的污染物,其中苯并[a]芘(BaP)属致癌性最强的PAHs之一。栉孔扇贝(Chlamys farreri)是我国北方近海重要的经济贝类。本论文以BaP作为PAHs的代表物,通过实验室实验和自然海区取样的方法,采用现代分析技术,研究了BaP在栉孔扇贝体内的毒代与毒效动力学规律,并建立了栉孔扇贝对BaP的生理毒代与毒效动力学模型(PBTK-TD model),在水产品安全、海洋生物保护和环境监测等领域具有指导意义。1.苯并[a]芘在栉孔扇贝体内累积和消除规律的研究本部分设置4个BaP染毒浓度,研究了BaP在栉孔扇贝组织中(包括软体部、鳃丝、血淋巴、消化盲囊和闭壳肌)累积和消除规律,结果显示BaP污染对栉孔扇贝体内BaP含量影响显著(P<0.05):扇贝血淋巴中BaP含量在染毒开始后就迅速升高并一直维持在较高的水平,各处理组之间无显著差异(P>0.05),结束曝污后只有0.05μg/L处理组血淋巴BaP含量在消除实验后期略微下降;扇贝其它组织BaP含量受水体中BaP浓度影响显著,同一组织不同曝污浓度以及相同曝污浓度不同组织中的BaP含量都有显著差异(P<0.05),各组织所有处理组BaP含量随时间均呈双峰变化,表现为染毒初期各组织中BaP含量迅速上升,紧接着小幅下降,之后又累积升高,在消除实验开始后,各组织中BaP含量迅速回落,之后趋于平缓,但实验结束时扇贝体内BaP含量还是维持在较高水平,各组织中BaP消除率与组织中脂肪含量负相关。可见栉孔扇贝对环境中BaP具有很强的富集能力,组织中BaP累积量具有明显的时间剂量效应。2.苯并[a]芘在栉孔扇贝体内生理毒代动力学模型的研究根据栉孔扇贝生理特征和BaP转运规律,构建了用于BaP在栉孔扇贝体内代谢动力学研究的生理模型。研究了不同曝污浓度下BaP在栉孔扇贝软体部、鳃丝、消化盲囊和闭壳肌中的毒代动力学规律:BaP在栉孔扇贝0.05μ/L处理组的软体部、鳃丝和闭壳肌,0.5μ/L处理组的软体部和闭壳肌以及5μ/L处理组的闭壳肌中符合一室开放模型,其它各组均符合二室开放模型;消除实验期间扇贝对BaP的消除动力学均符合二室开放模型。研究发现BaP能在扇贝体内快速累积,但消除半衰期较长,代谢排出速度较慢,根据实验所获得的毒代动力学参数可预测栉孔扇贝体内BaP的分布以及各组织中含量的经时变化规律,建立了BaP在栉孔扇贝体内的生理毒代动力学模型。3.苯并[a]芘在栉孔扇贝体内的毒代-毒效动力学模型研究本研究在栉孔扇贝对BaP生理毒代动力学研究的基础上,将毒性效应指标引入,研究了栉孔扇贝鳃丝和消化盲囊芳烃羟化酶(AHH)、脂质过氧化(MDA)、单细胞凝胶电泳和蛋白质羰基化水平等毒理指标的动力学规律,并将BaP在栉孔扇贝鳃丝和消化盲囊中的毒代和毒效动力学有机结合,探讨了BaP在栉孔扇贝组织中的生理毒代-毒效动力学模型(PBTK-TD model),发现组织中BaP含量与毒效指标表现出很好的时间和剂量同步行,剂量关系多符合一元三次方程关系,且相关性良好,可见栉孔扇贝鳃丝和消化盲囊中的毒性效应指标能在一定程度上指示组织中BaP的含量,BaP含量也能反应BaP对扇贝的损伤程度,这在水产品安全、海洋生物及海洋环境的保护具有一定的指导意义。4.青岛近海栉孔扇贝体内苯并[a]芘累积与毒性效应的野外调查本文选择了青岛近海3个取样位点(红石崖、太平角和8号码头)分别于2007年4月30日和7月30日取各海区表层海水和栉孔扇贝各组织测定了BaP含量,并分析了BaP对扇贝鳃丝和消耗盲囊毒性效应。结果显示两个时间所取三个位点海水中BaP的含量大小均为:8号码头>太平角>红石崖(P<0.05),并且7月30日所取的样品中BaP含量均高于4月30日所取的样品(P<0.05);分析扇贝体内累积量,发现鳃丝和软体部对水体中BaP污染较敏感,与水体中BaP浓度成正相关,且不同取样点差异显著(P<0.05),其它组织除8号码头消化盲囊中BaP含量较其它海区高外,均无显著差异(P>0.05);研究毒性效应得出以下结论:鳃丝和消化盲囊单细胞凝胶电泳与蛋白质羰基化含量对BaP污染较敏感,不同取样位点差异显著(P<0.05),拖尾率和蛋白质羰基化含量均与海水BaP浓度呈正相关,而AHH活力和MDA含量仅表现为8号码头扇贝鳃丝高于另外两个位点,其它均无显著差异(P>0.05)更多还原

【Abstract】 Recently, because of development of maritime petroleum, marine traffic and industry sewerage discharge, polycyclic aromatic hydrocarbon (PAHs) pollution became seriously. 16 kinds of PAHs became priority organic pollutants. Benzo[a]pyrene (BaP) is one of the most carcinogenic PAHs. Chlamys farreri is important economy bivalve cultured bu float valve in northern coast of China. We adopted laboratory study and sea area sampling, study the toxicokinetics and toxicodynamic of BaP in C. farrery,and a physiologically based toxicokinetic and toxicodynamic(PBTK-TD)model was developed for BaP in scallop (Chlamys farreri).What can be used in security of aquatic food, protection of halobios and oceanic environment.1. Research on bioaccumulation and elimination of benzo[a]pyrene in tissues of scallop (Chlamys farreri)In the experiment, 4 treatments were set up to investigate bioaccumulation and elimination of benzo[a]pyrene (BaP) in tissues (including soamtic tissue, gill,haemolymph, digestive gland and adductor muscle) of scallop (Chlamys farreri). The results suggested that BaP exposure had significant effects on BaP content in tissues of scallop (P<0.05). In haemolymph, there were no obvious difference of B[a]P content among all treatments (P<0.05). BaP content increased rapidly at the beginning of exposure and maintained at a high level during the experiment. After exposure cessation, B[a]P content in haemolymph descended appreciably at the late elimination experiment only in 0.05μg/L treatment. While BaP content in other tissues was affected markedly by BaP concentration of exposure water (P<0.05). There were marked difference of BaP content among the same tissue in different treatments, and the same situation were seen in different tissues treated with the same treatment. The change of BaP content of each tissue in all treatments exposure showed two peaks, that was at the beginning of exposure, BaP content in tissues rised rapidly, and then descended appreciably, but increased afterwards. At the initiation of elimination experiment, BaP content in tissues dropped swiftly and then became stabilization, which stayed at a high level at the end of the whole experiment. The elimination rate of BaP in all tissues showed negative relation with the lipid content in corresponding tissues. What can be concluded is that the ability of bioaccumulation of BaP in scallop is mighty and the cumulative content shows time response.2. A physiologically based toxicokinetic model for benzo[a]pyrene in Chlamys farreriThe Physiologically Based Toxicokinetic Model for Benzo [a] Pyrene (BaP) in Chlamys farreri physiological characteristic of C. farreri and transfer rule of BaP. This article mainly research about the toxicokinetics of BaP in somatic tissue , gill , digstive gland and adductor muscle : There are lots of deals present themselves as One-compartment Model , such as somatic tissue , gill and adductor muscle dealed with 0.05μg/L and 0.5μg/L , others are accord with Two-compartment Modle ; They are tally with Two-compartment Modle during the eliminate period . We can conclude from this experiment that BaP have the ability of accumulate in Chlamys farreri quickly , but the half life of elimination is to long , and the rate of metabolize is comparatively slow . The parameters of poison metabolize conclude from this experiment can forecast the distribution of BaP in Chlamys farreri and the change rule of content in different tissue , so the concise PBTK model came into being .3. A Toxicokinetic and toxicodynamic models for benzo[a]pyrene in Chlamys farreri Based on PBTK model for BaP in, this study we import toxicological index in gill and digestive gland: included AHH, MDA, single cell gel electrophoresis (SCGE) assay and oxidative carbonyl protein, a physiologically based toxicokinetic and toxicodynami(cPBTK-TD)model was developed for BaP in scallop (Chlamys farreri). We found that, BaP content and toxicological index in gill and digestive gland showed time and dose correlativity, accorded with cubic equation. What can be conclude is that the toxicological index in gill and digestive gland of scallop can reflect the BaP content in scallop tissue, whereas the component of BaP in tissue can direct the damage degree. It is very important for security of aquatic food, protection of halobios and sea environment.4. Bioaccumulation and toxicological effects of benzo[a]prrene in Chlamys farreri from offing of QingdaoSub-surface seawater and scallop (Chlamys farreri) samples at 3 sites(include Honsshiya, Taipingjiao and No.8 dock) in the sea area of the Qingdao in Apr. 30 and Jul. 30 of 2007, Benzo[a]Pyrene (BaP) content of seawater and tissue of scallop, toxicological index of gill and digestive gland were analyzed. As a result, the BaP in seawater is NO.8 dock > Taipingjiao > Hongshiya(P<0.05), in individual site April < July. Compare content of BaP in seawater and scallop tissue, a good correlation is observed between sea water and partial scallop tissue(gill and somatic tissue) (P<0.05), there is no significant difference between other tissue of scallop sampled from different sea areas.The frequencies of comet cells and oxidative carbonyl protein content in scallop tissue (gill and smatic tissue) were obtained as follows, No.8 dock > Taipingjiao > Hongshiya(P<0.05), AHH activity and MDA content had no significant difference, except the gill of scallop simpled from No.8 dock is higher than others.更多还原