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1.
鱼体甲基汞来源及半衰期的研究 总被引：1，自引：0，他引：1
松花江是我国汞污染较重的河流之一。历年累计输入江中的甲基汞为5．4吨，占输入总汞量(148．8吨)的3．8％。距离甲基汞污染源约23公里的哨口江段。历年江水中甲基汞平均含量仅占总汞平均含量的1～6．5％。而鱼体内甲基汞平均含量占总汞的比率则高达60％以上。为了摸清鱼体内甲基汞的来源。 相似文献
2.
以栉孔扇贝Chlamys farreri为研究对象,暴露于不同浓度HgCl2溶液35d后,转入自然海水中净化30d,检测不同时间点栉孔扇贝全组织中总汞与甲基汞含量,研究二者在栉孔扇贝组织中积累与净化情况.实验采用Kahle的双箱模型,数据处理采用两组不同动力学参数的双曲线毒性动力学模型.拟合发现,总汞和甲基汞在栉孔扇贝组织内的积累与净化规律符合双箱动力学模型;浓度低于2μg/L的汞溶液对栉孔扇贝的慢性毒性较小;各实验组暴露35d后栉孔扇贝组织中的总汞含量达到最高,暴露浓度与扇贝组织内的总汞积累量呈正比例关系.总汞在栉孔扇贝组织内的富集高峰出现在第35天,与理论点一致,而甲基汞富集高峰出现在40d后,有延迟现象;对比总汞和甲基汞在栉孔扇贝组织内的积累与净化动力学参数发现,总汞在栉孔扇贝组织内的积累因子（BCF）总体上大于甲基汞在栉孔扇贝组织内的BCF;汞与甲基汞在扇贝组织内的BCF和生物学半衰期（B1/2）与暴露液浓度均呈正相关关系;海水环境中总汞浓度低于0.064 8μg/L时,对栉孔扇贝的食品安全性无影响（以甲基汞为限量）. 相似文献
3.
《水产养殖》2014,(7):11-11
<正>汞是一种可以全球传输的对人体有害的重金属。前期研究指出,青藏高原的大气、水体、土壤等环境介质中汞的含量很低,是全球汞分布的背景区域之一。然而,关于青藏高原野生鱼类汞含量及富集作用的研究仍相当缺乏。日前,中国科学院青藏高原研究所联合香港科技大学开展了青藏高原野生鱼类汞含量的调查研究发现:在高原水体汞含量非常低的背景下,野生鱼体的汞含量相对较高,具有显著的富集作用,这与我国其他地区相对高汞污染环境中鱼体汞含量相对较低的结果形成鲜明对照。研究发现,高原特有野生鱼类在低温寡营养环境中具有极低的生长率和较长的寿命、较低的甲基汞去除率以及该地区水生生态系统食物链高效的甲基汞富集等,这些是造成汞富集的原因。 相似文献
4.
水产品中多环芳烃的检测方法及污染特征研究进展 总被引：1，自引：0，他引：1
多环芳烃作为持久性有机污染物,其来源广泛,易在生物体内富集且难以降解。水产品因能够为人体提供大量的蛋白质、脂肪和矿物质等营养物质而备受青睐,但由于受到水域环境污染的影响,其体内含有不同程度的多环芳烃污染物(PAHs)。而水生生物体内的PAHs通过食物链传递,在人体内蓄积,进而威胁人体健康。本文就PAHs的来源、分布迁移、在水产品中的检测方法及污染特征等方面进行综述。 相似文献
5.
镉对虾蟹毒性效应的研究进展 总被引：2，自引：0，他引：2
镉是一种半衰期很长的重金属元素,在生物体内有累积作用[1]。大量的镉进入水体中会引起水生生物的急性或慢性中毒,对器官、系统产生毒性影响,造成畸变甚至死亡[2]。虾、蟹是重要的水生生物资源,近年来由于重金属造成的生态环境污染,使其生产和种质资源遭到严重破坏,其中镉污染引起虾、蟹中毒的情况多有发生,并可通过食物链危害到人类的健康。因此,镉对虾蟹毒性影响的研究越来越受到重视。1镉在虾蟹体内的积累与分布水体中的镉可以通过呼吸、消化、体表渗透等途径被吸收到水生生物体中[3],在体内富集后,只有极少量被排出体外[4],通过测定虾蟹… 相似文献
6.
福建三都湾渔业环境和养殖生物体总汞含量及人体暴露健康风险评价 总被引：4，自引：0，他引：4
由于汞的生物甲基化和在食物链中的积累、放大作用,水产类膳食汞的摄入被认为是人体甲基汞负荷的主要来源。三都湾位于福建省东北部沿海,各类水产生物养殖面积1.5万hm2,年产量22.5万t。为评估甲基汞的健康风险,2004年在该湾采集海水样品9个、表层沉积物样品11个、养殖鱼类样品31个以及养殖贝类样品4个,用原子荧光光度法进行海水、沉积物和养殖生物总汞含量测定,对三都湾渔业环境汞污染现状和水产品质量安全进行评价。三都湾海水总汞含量范围在0.015～0.046μg/L,计(0.027±0.009)μg/L;沉积物总汞含量范围在0.055～0.113mg/kg,计(0.074±0.013)mg/kg,养殖贝类总汞含量范围在0.004～0.011mg/kg,计(0.008±0.005)mg/kg,与福建沿岸近20年来的其他相关调查结果相接近。养殖鱼类总汞含量范围在0.012～0.084mg/kg,计(0.032±0.006)mg/kg。通过调查数据的对比分析,三都湾鱼、贝类体总汞平均含量近30年来一直波动于鱼类汞含量的下限(0.05mg/kg)区间,与海水和沉积物汞的含量水平和变化趋势基本相对应;与美国、日本最近公布的鱼、贝类汞含量进行比较,三都湾牡蛎汞平均含量与日本的太平洋牡蛎和美国的牡蛎较接近,但三都湾牡蛎汞含量的最大值(0.011mg/kg)比日本、美国的牡蛎汞含量的最大值(0.250mg/kg和0.130mg/kg)低得多;三都湾大黄鱼、汞平均含量(0.026mg/kg和0.036mg/kg)和最大含量(0.084mg/kg和0.053mg/kg)均比美国的大西洋石首鱼(0.072mg/kg和0.148mg/kg)低;三都湾的鲈鱼汞平均含量(0.056mg/kg)低于日本的鲈鱼(0.100mg/kg)和美国的红鲈(0.128mg/kg)。后二者汞含量最大值(0.510mg/kg和0.625mg/kg)分别是三都湾养殖鲈鱼(0.075mg/kg)的6至8倍。三都湾海水、沉积物、贝类总汞含量符合国家环境质量标准,养殖鱼、贝类符合国家、WHO及欧盟的水产品汞限量要求。以100g/(人d)的水产类摄食量估算,食用鱼、贝类汞摄入量分别占JECFA推荐的汞临时性周可承受摄入量PTWI值的8.4%和2.9%;用总汞数据估算甲基汞摄入量分别占PTWI值的26.4%和9.0%。采用美国EPA设定的甲基汞RfD值估算,食用鱼、贝类甲基汞摄入量分别占60.3%和20.6%。三都湾沿海城乡居民水产品消费引起的汞暴露健康风险小。 相似文献
7.
为了解冰鲜鱼和水产配合饲料2种不同饲料对乌鳢(Ophiocephalus argus)中汞和甲基汞富集水平和食用安全的影响,实验采用ICP-MS法、液相-原子荧光分光光度法分别测定乌鳢在摄食冰鲜鱼和水产配合饲料两种不同饲料后,研究其肌肉、肝脏和肾脏3种不同组织中总汞和甲基汞的含量随养殖周期的富集规律。结果显示:在整个养殖过程中,饲料投喂组肌肉、肝脏和肾脏中总汞和甲基汞含量均低于冰鲜鱼投喂组,其中冰鲜鱼组肌肉、肝脏中总汞和甲基汞的富集均明显高于饲料组,肾脏中总汞的富集明显高于饲料组。从不同组织看,肌肉对总汞和甲基汞的富集显著高于肝脏和肾脏。肌肉中汞主要以甲基汞形式存在,平均含量占总汞的84.2%,低于国家食品安全限量标准,食用风险较低。相关性分析显示,2种不同饲料中总汞、甲基汞含量对乌鳢生长周期内总汞、甲基汞富集无显著性影响。结果表明乌鳢配合饲料养殖较冰鲜鱼养殖更为安全,适宜进一步推广运用。 相似文献
8.
鱼虾贝藻等水生生物生长在被污染的水体中,通过呼吸、体表以及食物链等途径,常常把毒物蓄积在体内,当人们在利用它们时由于有毒物质进入人体而危及健康,这是人所共知的现象,国内外亦有大量报导。日本轰动世界的水俣湾的“水俣病”及四日市的“骨痛病”就是由于人们食用汞、镉含量过高的水产品而引起的人体中毒事件的突出例子。因此测定生物体内的毒物物量是考察水体污染程度的一个重要方面。国内外对食品中有毒物质的含量制订了卫生标准,因此测定生物体内的毒物含量也是检查食品卫生、保障人民身体健康的一个重要方面。我 相似文献
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在《无公害水产品安全要求》及《无公害水产品产地环境要求》国家标准中,规定了总汞、砷等重金属的最高限量。当养殖水体受到污染,汞、砷含量超标时,它们与水体中众多生物活性物质发生反应,严重干扰水生生物的新陈代谢。汞、砷对水生生物的危害具有稳定性和累积性的特点,因此,当长期食用被汞、砷污染的水产品时,人的健康也将遭受严重的威胁。 相似文献
11.
Maximum limits of organic and inorganic mercury in fish feed 总被引：1，自引：0，他引：1
M.H.G. Berntssen K. Hylland K. Julshamn A.-K. Lundebye & R. Waagbø 《Aquaculture Nutrition》2004,10(2):83-97
The relatively high levels of mercury found in fish feeds might form a fish health and food safety risk. The present study aims to establish sublethal toxic threshold levels in fish and assess feed‐fillet transfer of dietary mercury. Atlantic salmon (Salmo salar L.) parr were fed for 4 months on fish meal‐based diets supplemented with mercuric chloride (0, 0.1, 1, 10 or 100 mg Hg kg?1 dry weight (DW)) or methylmercuric chloride (0, 0.1, 0.5, 5 or 10 mg MeHg kg?1 DW). At the end of the experiment, dietary inorganic mercury mainly accumulated in intestine (80% of body burden) and assimilation was low (6%). In contrast, methylmercury readily accumulated in internal organs and muscle (80% of body burden) and had a relatively high assimilation (23%). Highest accumulation of dietary inorganic mercury was observed in the gut and kidney. Fish fed 10 mg Hg kg?1 had an early (after 2 months) significant increase in renal metallothionein (MT) level and intestinal cell proliferation, followed by intestinal pathological conditions after 4 months of exposure. At 100 mg Hg kg?1, intestinal and renal function were reduced as seen from the significantly reduced protein and glycogen digestibility and increased plasma creatinine levels. For dietary methylmercury (MeHg), highest accumulation was found in blood and muscle. Intestinal cell proliferation and liver MT significantly increased at 5 mg MeHg kg?1 after 2 months of exposure. At the end of the experiment, blood haematology was significantly affected in fish fed 5 mg MeHg kg?1 and these fish exceeded the current food safety limit for mercury. Tissue MT induction and intestinal cell proliferation appeared to be useful and quantifiable early indicators of toxic mercury exposures. Based on the absence of induction of these early biological markers such as MT and cell proliferation, nonobserved effect levels (NOELs) could be set to 0.5 mg Hg kg?1 for dietary methylmercury and 1 mg Hg kg?1 for inorganic mercury. Lowest observed effect levels (LOELs) levels could be set to 5 mg kg?1 for methylmercury and 10 mg Hg kg?1 for inorganic mercury. 相似文献
12.
海水桡足类的营养及在鱼、虾、蟹幼体培育中的应用 总被引：1，自引：0，他引：1
海水桡足类在海洋食物网和生态系统中具有重要的地位,是各种海洋经济鱼类和甲壳类的重要饵料,也是经济水产动物人工育苗阶段的优质活饵料源。研究海水桡足类营养和应用效果,对提高海水鱼、虾、蟹类幼体变态率、成活率、苗种质量和育苗成功率具有重要的意义。 相似文献
13.
ABSTRACT: The distribution of mercury in the muscle and other tissues was determined in 23 species of fishes and invertebrates. This study reveals species-specific patterns of mercury accumulation in the muscle of tuna and alfonsino. Consistently high levels of total mercury were found in Beryx splendens (0.78 ± 0.56 µg/g), Atlantic Thunnus thynnus (0.42 ± 0.06 µg/g), Pacific T. thynnus (0.59 ± 0.34 µg/g), Thunnus obesus (0.98 ± 0.34 µg/g), Makaira nigricans (0.56 ± 0.05 µg/g), Tetraptrus audax (0.51 ± 0.08 µg/g), and Xiphias gladius (0.47 ± 0.24 µg/g). Other fish species had lower levels of total mercury or methylmercury in muscle than the maximum permitted level of mercury in fish in Japan (0.4 µg/g). Total mercury and methylmercury levels in the muscles of T. thynnus , T. obesus, and B. splendens were closely correlated with body weight. 相似文献
14.
本文报导虎嘉鱼(Hucho bIeekeri K.)的食性及食物消化的研究结果,其食性以水生昆虫和鱼类为主食。虎嘉鱼是较有经济价值的鱼类,这一研究对虎嘉鱼的开发和利用及人工养殖提供了科学依据。 相似文献
15.
亚硝酸盐在水生动物体内的吸收机制及蓄积的影响因素 总被引：8，自引：2，他引：8
亚硝酸盐是水产养殖系统中一种潜在的污染物,淡水鱼类通过鳃主动吸收亚硝酸盐,导致体内亚硝酸盐的浓度过高。海水鱼类对亚硝酸盐的敏感性较低,但仍可以通过肠和鳃吸收亚硝酸盐。影响亚硝酸盐在体内蓄积的因素很多,文章就亚硝酸盐在水生动物体内的吸收及蓄积的影响因素这2个方面进行了论述。 相似文献
16.
The aim of the present study was to investigate concentrations of total mercury (THg) and methylmercury (MeHG) in the common
carp from Czech ponds of Rožmberk, Spolsky, Nezmar, and Velky Bědny. Seven common carps (Cyprinus
caprio) from each of the ponds were caught. Muscle tissue, the liver, and the soft and hard roe were used for the tests. Total mercury
and methylmercury were found in all the muscle tissue samples examined. Detection limits for total mercury and methylmercury
determination methods were 0.001 mg kg–1 and 0.013 mg kg−1 respectively. Methylmercury levels in the liver and gonads were below the method’s limits of detection. THg and MeHg concentrations
in muscle tissues were 0.018–0.063 mg kg–1 w.w. and 0.019–0.063 mg kg–1 w.w. respectively. MeHg made up 90–100% of THg in muscle tissues. Total mercury and methylmercury concentrations were significantly
(P < 0.05) higher in fish from the Spolsky pond than from the Nezmar pond. MeHg/THg ratios were significantly (P < 0.05) higher in fish from the Rožmberk, Spolsky and Nezmar ponds compared with fish from the Velky Bědny pond. 相似文献
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水产品中镉的形态分析及其危害 总被引：6，自引：0，他引：6
镉是生物体非必需的微量有害元素之一。近年来,随着工业污染加剧,造成水生动物体内镉超标。镉残留时间长,能蓄积,可沿食物链转移,从而对人体健康造成威胁。水产品中的镉形态复杂,本文就镉污染来源、存在形态及不同形态对水产动物危害和其检测手段等做一综述。 相似文献
19.
Abstract. Polychlorinated biphenyls (PCBs), chlorinated pesticides and mercury were analysed in cultivated eels, Anguilla anguilla L., and their food. In one experiment the eels were mainly fed with a low-fat diet. In another experiment cultivated eels were fed a high-fat diet. Both experiments showed that the major part of the organochlorine compounds and mercury present in the diet was retained by the eel. The retention of the organochlorine compounds and mercury was estimated at 50–70% after an exposure period of about 1 year.
Although the mechanisms of accumulation of mercury and organochlorine compounds clearly differ, no differences in retention were found. The remaining mercury, PCBs and pesticides which were not retained possibly pass through the alimentary canal rather than being accumulated first and metabolized or excreted during the feeding period.
Due to these high levels of accumulation monitoring levels of PCBs, chlorinated pesticides and mercury in the diet is essential for protection of the quality of cultivated eels. 相似文献
Although the mechanisms of accumulation of mercury and organochlorine compounds clearly differ, no differences in retention were found. The remaining mercury, PCBs and pesticides which were not retained possibly pass through the alimentary canal rather than being accumulated first and metabolized or excreted during the feeding period.
Due to these high levels of accumulation monitoring levels of PCBs, chlorinated pesticides and mercury in the diet is essential for protection of the quality of cultivated eels. 相似文献