长江重庆江段鱼类污染状况

通过残毒分析发现，重庆江段的鱼体受到不同程度的污染。鱼体中主要污染物Ｃｄ、Ｃｒ、Ａｓ等的负荷比较高，但未超标，食用品质较好。鱼样外周血红细胞微核率为０８２‰～４２８‰，表明重庆江段水质对鱼体细胞具诱变作用。

鱼类污染中毒的肉眼判断

1.重金属污染中毒。重金属是指密度比较大的金属,如铅、锰、锌等。中毒鱼类鳃部呈灰白色,并分泌大量黏液,形成絮状沉积物,使鱼鳃阻塞,引起呼吸障碍,中毒鱼类常在水表层浮游。鱼类铅中毒,体色明显呈黑色。鱼类铜中毒,体色呈灰白色,鳃丝呈浅绿色。

不容忽视的鱼类污染

随着生活水平的提高,人们已特别喜欢吃鱼。但对鱼类的污染问题,却很少有人问津和了解,所以误贪污染鱼类的事件频频发生。同时人们也不要认为活鱼就新鲜,因为即使受了工业废水和生活废水污染的鱼类,也往往能生存,但这些鱼体中已富集了一定量的有毒有害物质,如果经常食用,也会在人体中富集起来,最终损害人体健康。

上海黄浦江水系常见鱼类重金属含量及健康风险评价

黄浦江是兼具饮用水源、航运、排洪排涝、渔业、旅游等功能的上海“母亲河”,鱼类资源丰富。为了解黄浦江水系鱼类重金属污染状况,测定了黄浦江水系15种优势鱼类和主要经济鱼类肌肉中Cu、Zn、Fe、Mn、Pb、Cd、Cr、As、Hg的含量。结果表明,除As外,所有鱼体中的重金属含量均低于国家标准限值或农业行业标准限值。综合污染指数分析结果显示:淀山湖水域翘嘴鲌、大鳍■为重金属中度污染(2.03.0);苏州河水域翘嘴鲌、兴凯■为中度污染,大鳍■为重度污染。健康风险分析结果显示,除As外,Cu、Zn、Pb、Cd、Cr、Hg、Mn等的健康风险指数均小于1,对人群的健康风险不显著。复合重金属危害系数(TTHQ)分析结果显示:黄浦江水域似鳊的TTHQ值为0.957;苏州河水域光泽黄颡鱼、刀鲚、似鳊、翘嘴鲌、■、大鳍■、日本鳗鲡、兴凯■的TTHQ值均大于1;淀山湖水域泥鳅的TTHQ值接近1,翘嘴鲌、黄颡鱼、■、大鳍■的TTHQ值大于1。以上鱼类均存在复合重金属健康风险。目前,淀山湖水域仍有专业渔民开展捕捞作业,因此,应对当地居民重金属健康风险作长期监测。

Pollution of Environmental Endocrine Disrupting Chemicals(EDCs) in Water and Its Adverse Reproductive Effect on Fish

Environmental endocrine disrupting chemicals （EDCs）, commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, more and more EDCs were released into the environment. EDCs go into water body via atmosphere sedi-mentation, surface runoff, soil eluviation, etc., so water body becomes the main place for existing. In order to attract scientific and public attention worldwide and to prevent EDCs pol ution, in this study we reviewed the classification of EDCs and their concentrations in natural water bodies, drinking water sources and water plants, and the reproductive toxicity of EDCs to fish were reviewed. EDCs could disturb the endocrine system and make reproductive organs and reproduction abnor-mal, resulting in fertility descending, reproduction function damage, community quan-tity decrease and even species extinction. In addition, EDCs could disrupt the homeostasis maintained by hormones, which would result in defects of neural de-velopment and abnormalities of the endocrine and reproductive systems. The exact molecular mechanisms have not been completely reported, but researches have suggested that multiple mechanisms were involved in the action of EDCs. Although there have been researches on the biohazard of EDCs, there stil exist problems of weakness in fundamental researches, difficulties in recognizing and identifying EDCs and high cost, which restraint the knowledge on them.

Levels of Polychlorinated Biphenyls （PCB） in Fish from the Lakes of the Warmia and Mazury Region

The term polychlorinated biphenyls, or PCBs refers to a class of synthetic organic chemicals that are, to a large degree, chemically inert. PCBs are not found in a nature as a natural compounds and its appearance in natural environment is connected with unintentional and irresponsible human activity. PCBs have been produced on an industrial scale for more than 50 years and have been exported as chemicals in products to almost every country in the world. PCBs were commonly used as dielectric fluids in transformers and capacitors, in heat transfer and hydraulic systems. Other uses of PCBs included the formulation of lubricating and cutting oils, as plasticizers in paints. Nowadays PCBs are ranked among the compounds called POP （Persistent Organic Pollutants）. This group of hazard removable pollutants includes pesticides, dioxins and furans also. Fishes fished from August 2006 to December 2007 from lakes in north-east Poland： Lafiskie, Kisajno and Niegocin. The investigations were carried out on four fish species： roach, common bream, perch and pike. According to the preliminary mass and length measurements anticipatory treatment were realized. Subsequently fishes were analysed in accordance with National Institute of Hygiene method. According to the investigations results PCBs were found in fish muscular tissues, fished from north-east lakes. PCB level didn＇t exceed the highest acceptable daily dose （4pg-TEQ body mass/day）.

Mercury Exposure Assessment in Iraqi Women＇s Hair with Respect to Fish Consumption and Contamination in Marshland （Southern Iraq）

This study investigated the level of mercury in hair samples of pregnant women and newborns living in marshes. Hair mercury concentration, as an indicator of mercury body load, was studied in 30 samples of indigenous women and newborns to assess the association between fish consumption and specific characteristics that can influence exposure. In January 2013, 40 pregnant women were invited to participate. An interview was administered and a questionnaire was used to collect information about age, body weight, height, fish （fresh） consumption, pregnancy stage, residence duration, education level, family income and number of dental amalgam fillings. The results showed that for hair total Hg concentration was 6.47 p.g/g （6.47 ~ 0.71 pg/g）. About 5.9% of mothers had hair total Hg levels in excess of 14 ~tg/g. Maternal hair mercury was above the threshold level of WHO （World Health Organization） （5 pg/g）. As expected, there was a clear increase in hair Hg with reported fresh fish consumption （p = 0.08）. The highest mean in a group who consumed fish several times per week was 5.93 lag/g. Moreover, a significant effect of age and residential time on Hg in women＇s hair was found such as the older women.

Distribution of Mercury in a Gadoid Fish Species, Tusk （Brosme brosme）, and Its Implication for Food Safety

The tusk （Brosme brosme） is a popular gadoid fish for human consumption, which also is susceptible to mercury accumulation. However, few data of mercury levels in tusk exist, and it is difficult to compare tusk fished from assumed contaminated areas with background levels. The aim of this study was to increase the information of mercury levels observed in tusk from the Northeast Atlantic Ocean. Samples of tusk were collected from seven different localities in open ocean areas, nine along the Norwegian coastal current （NCC）, and from two fjord stations. Determinations of mercury in muscle and liver were carried out using inductive coupled plasma mass spectrometry （ICPMS） after microwave-assisted wet digestion. The highest concentrations of mercury in muscle were found in tusk captured from the fjords Hardangerfjord and Sorfjord, and had mean concentrations of mercury at 1.5 and 1.7 mg kg＂~ wet weight （ww）, respectively, where all of the tusk exceeded EU＇s upper limit of 0.5 mg kg1 ww. The lowest concentrations of mercury were observed in tusk captured from the open ocean areas, and the concentrations ranged from 0.08 to 0.30 mg kg-1 ww. Mercury concentrations of tusk captured along the NCC ranged from 0.21 to 0.49 mg kg-1 ww. Mercury concentrations increased with the weight of the tusk, and variance analysis （ANOVA） of weight normalized mercury concentrations showed that there were significant differences in mercury concentrations between tusk collected from the open ocean, NCC and fjords, which indicates that differences in mercury concentration between different areas arecaused by other factors.

Pollutants and fish predator/prey behavior： A review of laboratory and field approaches

Fish behavior can be altered by contaminants. There is an extensive literature on laboratory behavioral assays, with many chemicals impairing feeding or predator avoidance. However, there is not extensive work on fishes that live in contami- nated environments. Therefore, we then review our recent research on feeding and trophic relations of populations from contami- nated estuaries compared with relatively unpolluted sites. The mummichog Fundulus heteroclitus, is a non-migratory fish; those from more contaminated areas are poor predators and slower to capture active prey （grass shrimp, Palaemonetes pugio）. In the field, they consume much detritus and sediment, which is not nutritious. They are less active than fish from cleaner sites and more vulnerable to predation. They have altered thyroid glands and neurotransmitter levels, which may underlie altered behaviors Fish from the reference site kept in tanks with sediment and food from the polluted site showed bioaccumulation and reduced prey capture after two months, although fish from the polluted site did not show significant improvement when maintained in a clean environment. Poor nutrition and predator avoidance may be responsible for their being smaller and having a shorter life span than reference fish. Bluefish Pomatomus saltatrix, are a marine species in which the young-of-the-year spend their first summer in es- tuaries. We found bioaccumulation of contaminants and reduced activity, schooling, and feeding in young-of-the-year bluefish from a relatively unpolluted site that were fed prey fish from a contaminated site. They also had altered thyroid glands and neuro- transmitter levels. Many field-caught specimens had empty stomachs, which is rare in this species. In the fall, when they migrate back out to the ocean, they are smaller, slower, and more likely to starve or to be eaten than those that spent their summer in cleaner estuaries [Current Zoology 58 （1）： 9-20, 2012].