人体发汞值与汞摄入量关系的探讨

根据对１２１０份发汞测得的结果认为发汞值属正偏态分布，但可以通过对数变换成为对数正态分布进行统计分析。发汞值与日均汞摄入量有关，监测发汞值可以推算人体环境汞暴露的水平，并提出了推算的方法。     

尿汞及发汞值作为汞污染区人群健康监护指标的意义

尿汞及发汞值作为汞污染区人群健康监护指标的意义巴月，张毅，崔留欣，程学敏，杨建勋，刘华莲，杨金勋，秦建学河南医科大学环境卫生学教研室（郑州４５００５２）关于尿汞值、发汞值作为人体汞负荷水平或慢性汞中毒诊断指标的意义，已有报道［１、２］；但其多是对职业...     

兰州地区Hg污染

汞在兰州地区环境中污染最重、分布最广、危害最大的元素。汞元素的来源主要是烟尘、工业废水、废渣、废气。干燥气候，汽车及人类活动对尘土的细化，加大了沙尘、地尘、降尘中汞的富集，从而加重了汞对人体的危害。     

某金矿冶炼厂汞污染对人体健康效应的调查

为探讨环境汞污染对人体健康效应,调查某金矿冶炼厂内外空气、土壤和野生植物汞污染情况及测定该厂区车间内外职业人群和非职业人群发汞、尿汞含量。结果表明,环境汞含量明显超标,职业人群尿汞平均含量０．０８８±０．０７８ｍｇ／Ｌ,发汞平均含量４．８８±３．８５μｇ／ｇ,二者差异有显著性意义（Ｐ＜０．０１）。提示：金冶炼厂环境污染对人体健康产生一定影响     

汞对人体健康的影响及其防治

自从日本发生水俣病以来，汞对人体的危害日益受到广泛关注。本文就近几年汞对中枢神经系统、肝脏、肾脏和生殖系统等的毒性影响作一综述，重点阐述了汞对神经系统的毒性机制和汞中毒的防治。     

甘医院职业性汞危害的调查

目的 了解某医院汞泄漏事故及汞吸收、汞中毒发病情况，消除汞危害。方法 调查事故过程；检测工作场所空气汞浓度；开展全员尿汞检查；对住院病例进行分析。结果 医院检验科未重视汞的防护，本次汞泄漏事故损耗汞约35ml。调查发现该院汞吸收与汞中毒的检出率为6．97％，职业性汞中毒发病率为2．24％。结论 检验人员的汞吸收、汞中毒与实验室用汞有关，必须重视医院汞危害的预防。     

汞的污染及其对动植物和人的危害

汞是一种有毒的重要金属元素，在工业上应用极广。汞对生物体毒性很高，汞的污染对其周围的动植物用人体造成了很大的危害。     

排除汞毒害的饮食调理

经过多方面调查统计,汞进入人体约有90％以上是通过食用鱼类等水产品摄进的。在汞污染严重地区,吃鱼虾多的人,头发中汞含量高达50微克。这主要是因为水生生物“食物链”的传递作用,将水中汞富集于体内。尽管水中汞的含量很低,但经过鱼体的富集作用,鱼体中的汞含量可增加到水中汞含量的数千倍乃至数万倍。另外,外界污染到水中汞是无机汞,对人体危害较轻。     

27例个体采金作业者汞负荷情况

２７例个体采金作业者汞负荷情况广东省职业病防治院（广州市新港西路１６５号，５１０３１０）翁丽娜潘金城金属汞对人体的危害常由于吸入汞蒸气所致。急性汞中毒患者主要发生于短期内吸入高浓度汞蒸气之后，在动物实验中也表明有明显的剂量—反应关系，如狗吸入金属汞蒸...     

微波密闭消解—冷原子吸收法测定生物样品中微量汞

微波密闭消解—冷原子吸收法测定生物样品中微量汞郝琳马强王叔淳商伯东天津市食品卫生监督检验所（天津３０００１１）汞对环境的污染，是世界关注的课题，汞随食物链而进入人体，在机体内蓄积可引起慢性中毒，汞对人体的危害是人们极为重视的。我国食品卫生标准对各类食...     

Inorganic and organic mercury in blood,urine and hair in low level mercury vapour exposure

Summary Fourteen Japanese females exposed to elemantal mercury vapour of concentration; 0.001–0.019 mg Hg/m³, were examined for inorganic and organic mercury concentrations in red blood cells, plasma, urine, and hair. Examinations were conducted the times; at 0,4 and 8 months of mercury exposure. No significant change of inorganic and organic mercury in urine was observed for three examinations. Both inorganic and organic mercury in plasma, and only organic mercury in red blood cells, increased significantly after commencement of mercury work. The hair organic mercury values stayed constant. The intake of organic mercury was judged as constant from the constancy of hair mercury values, and the change of organic mercury concentrations in plasma and red blood cells must have been elicited from the intake of elemental mercury. The reason why the increase of plasma mercury values did not reflect to urine mercury values was discussed.Supported by the grant from the Japanese Ministry of Education     

Distribution and retention of organic and inorganic mercury in methyl mercury-treated neonatal rats

Seven-day-old Long Evans rats received one mumol of 203Hg-labeled methyl mercury/kg sc and whole body retention and tissue distribution of organic and inorganic mercury were examined for 32 days postdosing. Neonates cleared mercury slowly until 10 days postdosing when the clearance rate abruptly increased. During the interval when whole body clearance of mercury was extremely slow, methyl mercury was metabolized to inorganic mercury. Peak concentration of mercury in kidney occurred at 2 days postdosing. At 32 days postdosing, 8% of mercury in kidney was in an organic from. Liver mercury concentration peaked at 2 days postdosing and organic mercury accounted for 38% at 32 days postdosing. Brain concentrations of mercury peaked at 2 days postdosing. At 10 days postdosing, organic mercury accounted for 86% of the brain mercury burden, and, at 32 days postdosing, for 60%. The percentage of mercury body burden in pelt rose from 30 to 70% between 1 and 10 days postdosing. At 32 days postdosing pelt contained 85% of the body burden of mercury. At all time points, about 95% of mercury in pelt was in an organic form. Compartmental analysis of these data permitted development of a model to describe the distribution and excretion of organic and inorganic mercury in methyl mercury-treated neonatal rats.     

Assessing the source of mercury in foliar tissue of quaking aspen

Foliar accumulation of mercury has been demonstrated to occur as plants leaf out, yet the primary source of this mercury is not known. Using closed-system growth chambers, uptake of mercury by quaking aspen (Populus tremuloides) foliage was measured over time as a function of soil mercury concentrations (0.01, 6.2, and 25.6 microg/g) and atmospheric mercury exposure concentrations (1.4, 14.9, and 68.5 ng/m3). Foliar mercury concentrations increased as a function of time for all exposures. Twice during the experiment, leaf washes were analyzed for mercury to assess surface deposition, and little mercury was removed (0.02-0.04 ng/m2), suggesting that direct deposition to the leaf surface was not significant during this experiment. At the end of the four-month experiment, whole-plant mercury concentrations were determined. It was found that whereas mercury in the atmosphere primarily influenced foliar uptake, root concentrations were related to the soil mercury concentration. The implication of this study is that litterfall may serve as a pathway for new, atmospherically derived mercury to be deposited to forest soils. This has significant implications for watershed management of ecosystems where mercury is of concern.     

Relation of mercury exposure to elemental mercury levels in the urine and blood

The levels of elemental and inorganic mercury were measured in urine and blood samples from workers in thermometer manufacturing factories. The inorganic mercury levels in the urine did not correlate with the levels of mercury exposure for each worker. However, a significant correlation was noted between elemental mercury levels in the urine and the levels of individual exposure. A significant correlation was also found between elemental mercury levels in the urine and mercury levels in the blood. These findings suggest that the determination of elemental mercury in urine may serve as a useful indicator for assessing levels of recent exposure to mercury vapor, as well as the level of inorganic mercury in the blood.     

Scalp hair as a biomarker in environmental and occupational mercury exposed populations: suitable or not?

Hair is a well-established and widely used matrix for measuring mercury exposure of an individual. Although a variety of washing procedures to remove external mercury contamination have been proposed, no standardized procedures are available yet. In this study, different washing reagents like l-cysteine (Cys), 2-mercaptoethanol (ME), and disodium diaminoethanetetra acetate (EDTA) were used to find out if it is possible to remove mercury contamination from human scalp hair spiked with HgCl2 solutions at different concentrations. It was found that the external mercury contamination could not be fully washed off even using reagents with high affinity to mercury like l-cysteine and ME. However, for the well-pulverized CRM hair samples some of the endogenous mercury was washed off. It suggests that hair is not a suitable biomarker for evaluation of total mercury exposure especially in people like mercury miners or gold miners/burners associated with serious external Hg exposure. However, hair still can be used as an indicator for methyl mercury exposure because, generally, there is almost no exogenous contamination of methyl mercury in hair.     

Distribution of Total Mercury and Methyl Mercury in Water, Sediment, and Fish from South Florida Estuaries

Concentrations of total mercury and methyl mercury were determined in sediment and fish collected from estuarine waters of Florida to understand their distribution and partitioning. Total mercury concentrations in sediments ranged from 1 to 219 ng/g dry wt. Methyl mercury accounted for, on average, 0.77% of total mercury in sediment. Methyl mercury concentrations were not correlated with total mercury or organic carbon content in sediments. The concentrations of total mercury in fish muscle were between 0.03 and 2.22 (mean: 0.31) μg/g, wet wt, with methyl mercury contributing 83% of total mercury. Methyl mercury concentrations in fish muscle were directly proportional to total mercury concentrations. The relationship of total and methyl mercury concentrations in fish to those of sediments from corresponding locations was fish-species dependent, in addition to several abiotic factors. Among fish species analyzed, hardhead catfish, gafftopsail catfish, and sand seatrout contained the highest concentrations of mercury. Filtered water samples from canals and creeks that discharge into the Florida Bay showed mercury concentrations of 3–7.4 ng/L, with methyl mercury accounting for <0.03–52% of the total mercury. Consumption of fish containing 0.31 μg mercury/g wet wt, the mean concentration found in this study, at rates greater than 70 g/day, was estimated to be hazardous to human health. Received: 3 July 1997/Accepted: 2 September 1997     

Canadian mercury inventories: the missing pieces

Research was conducted to determine the significance of the deliberate use of mercury in products in Canada and the associated releases from these sources. Through a combination of literature review and new calculations, the reservoir, flux, and releases of mercury from eight product sources were calculated, and these results compared to historical Canadian inventories. Mercury contributions from the waste sector were also assessed and compared to total Canadian mercury releases and to mercury releases from coal-fired generating stations. Results suggest the use and release of mercury associated with release of mercury associated with its use in products is 4.5 times what previous inventories indicate. Including dental amalgam and sewage sludge, the total releases of mercury to all environmental compartments in Canada totals 20 tonnes per year. This accounts for less than one-half of the 44 tonnes per year of mercury released from mercury waste disposal each year in Canada. Waste mercury contributions from hazardous waste imports, unknown product sources, and incomplete information on the use of mercury in known products may account for this discrepancy. Waste-related mercury releases and transfers for disposal and recycling are 11 times greater than that of electricity generation in Canada. Results indicate that Canadian inventories have underestimated the significance of mercury use and release associated with products, calling into question the current priorities for mercury management. This paper was developed as part of a panel session at the International Joint Commission "Mercury in the Ecosystem" workshop, February 26-27, 2003, Windsor, ON, Canada, as a complement to the information on Canadian Inventories presented by Luke Trip (Senes Consulting, Ottawa, ON, Canada).     

Microenvironmental exposure to mercury vapor

Work area and breathing zone samples were collected in a factory utilizing metallic mercury and analyzed for mercury vapor content. Breathing zone samples averaged several fold higher in concentration than concurrent area samples, reflecting a "microenvironmental" exposure to mercury vapor, presumably from contaminated clothing and hands. Blood and corrected total urine mercury values correlated well with the average microenvironmental exposure level for each worker. Measurements of unbound mercury in urine samples were sensitive at picking up minimal exposures. Excessive amounts of unbound mercury were not found in the urine, even with wide day-to-day swings in microenvironmental mercury vapor levels, suggesting that the human body can adapt to a chronic, moderate exposure to mercury vapor.     

Radioactive Mercury Distribution in Biological Fluids and Excretion in Human Subjects after Inhalation of Mercury Vapor

The distribution of mercury in red blood cells (RBCs) and plasma, and its excretion in urine and feces are described in five human subjects during the first 7 days following inhalation of radioactive mercury vapor. A major portion (98%) of radioactive mercury in whole blood is initially accumulated in the RBCs and is transferred partly to the plasma compartment until the ratio of mercury in RBCs to plasma is about 2 within 20 hr. The cumulative urinary and fecal excretion of mercury for 7 days is about 11.6% of the retained dose, and is closely related to the percent decline in body burden of mercury. There is little correlation between either the urinary excretion and plasma radioactivity of mercury, or the specific activities of urine and plasma mercury, suggesting a mechanism other than a direct glomerular filtration involved in the urinary excretion of recently exposed mercury. These studies suggest that blood mercury levels can be used as an index of recent exposure, while urinary levels may be an index of renal concentration of mercury. However, there is no reliable index for mercury concentration in the brain.     

Mercury exposure from domestic and imported estuarine and marine fish in the U.S. seafood market

BACKGROUND: Methylmercury exposure causes a variety of adverse effects on human health. Per capita estimates of mercury exposure are critical for risk assessments and for developing effective risk management strategies. OBJECTIVE: This study investigated the impact of natural stochasticity in mercury concentrations among fish and shellfish harvested from the Atlantic Ocean, Pacific Ocean, and foreign shores on estimated mercury exposures. METHODS: Mercury concentrations and seafood consumption are grouped by supply region (Atlantic Ocean, Pacific Ocean, and foreign shores). Distributions of intakes from this study are compared with values obtained using national FDA (Food and Drug Administration) mercury survey data to assess the significance of geographic variability in mercury concentrations on exposure estimates. RESULTS: Per capita mercury intake rates calculated using FDA mercury data differ significantly from those based on mercury concentration data for each supply area and intakes calculated for the 90th percentile of mercury concentrations. CONCLUSIONS: Differences in reported mercury concentrations can significantly affect per capita mercury intake estimates, pointing to the importance of spatially refined mercury concentration data. This analysis shows that national exposure estimates are most influenced by reported concentrations in imported tuna, swordfish, and shrimp; Pacific pollock; and Atlantic crabs. Collecting additional mercury concentration data for these seafood categories would improve the accuracy of national exposure estimates.