直接测汞仪测定尿中总汞

【目的】建立以直接测汞仪测定尿汞的方法。【方法】利用DMA80型直接测汞仪对尿样进行分析测定。【结果】该方法在尿汞为1.0～200.0 ng水平时具有良好的线性关系,该方法检出限为0.4μg/L,样品测定精密度为0.38%～1.68%,回收率为92.6%～96.9%。【结论】该方法可以作为尿中总汞的日常检测方法。     

Serum hormone and biochemical activity as biomarkers of mercury toxicity in the yellowfin seabream Acanthopagrus latus

This study was undertaken in two separate environmental and experimental conditions. The environmental test was carried out at creeks in the Persian Gulf and the experimental test was undertaken in seawater re-circulatory tanks. Mercury concentrations were determined using a standard cold vapour atomic absorption method. Serum enzymes were determined with Diagnostics Infinity reagent kit. Serum glucose and total protein were measured photometrically. Serum hormones were assayed using diagnostic ELISA kits. Results of the present investigation indicated that the sub-acute and chronic mercury concentrations tested may cause several changes in the biochemical and hormone parameters of the studied fish and we can use these changes as biomarkers for mercury detection. The range of mercury concentrations found in the creek water and specially sediments along the Mahshahr coast was higher than the other marine environment. It was declared that between enzymatic indices serum acid phosphatase (ACP) amount and ACP activity, between hormonal indices testosterone, T3 and T3/T4 and between metabolite index total protein can be considered as suitable and effective biomarkers of mercury pollution in yellowfin seabream.     

Effect of sublethal dose of mercury toxicity on liver cells and tissue of yellowfin seabream

The aim of the present study was to provide baseline data on the prevalence of histopathological liver lesions in Acanthopagrus latus under experimental mercury exposure. Experimental study was at seawater recirculatory tanks. Mercury concentrations were determined using a standard cold vapour atomic absorption. Histopathological analyses were done in tissue processor and the slides were stained with haematoxylin and counterstained with eosin. There were many liver lesions including enlarged and lateral nuclei, nuclear degeneration and vacuolation; oncotic, apoptic, focal, massive, centrilobular and periportal necrosis; atrophy, lipidosis, hydropic and cloudy swelling, oval cell proliferation; bile stagnation, dilation of sinusoid, intracellular oedema and dark granules in both field and laboratory conditions. In conclusion the present investigation indicated that mercury is a toxic substance in yellowfin seabream and the sublethal concentrations of mercury may cause several changes in the histological indices of the studied fish, and we can use these changes as biomarkers of mercury detection.     

Concentrations and health risk assessment of total mercury in canned tuna marketed in Southest Brazil

The aim of this research was to determine total mercury (Hg) content in 69 canned tuna of 13 brands marketed in southwest Brazil. All values are reported in μg.g⁻¹ wet weight basis. Potential health risk was estimated on the basis of mercury concentration and average consumption (175 g/per week) of fish in Brazil comparing to PTWI of 1.6 μg.kg⁻¹ (FAO/WHO, 2010). A large variation in the concentration of mercury in different species was observed. Mean mercury concentration was 0.256 ± 0.215 μg.g⁻¹ with a highest value of 1.060 μg.g⁻¹ in a single can. In general average concentration was below the legislation of 1.0 μg.g⁻¹ for predatory species (BRASIL, 2010). Estimate weekly intake (EWI) varied 0.2–1.7 μg.kg⁻¹. For the analyzed brands and Brazilian fish consumption, no human health risk is likely to occur. However one brand was higher than PTWI of 1.6 μg.kg⁻¹ showing no safety for specific risk group. Further studies including specific data on canned tuna consumption in specific populations will be needed as well as the fish type, fish size and fishing location.     

测汞仪直接测定并评价鲫鱼组织中汞含量

目的:建立用测汞仪直接测定并评价南京地区超市和农贸市场所售鲫鱼组织中的汞含量。方法:用直接测汞仪,分别测定鱼皮、鱼脑、鱼肉及鱼籽组织中的汞含量。结果:鲫鱼组织中的汞含量呈如下规律:鱼脑>鱼皮>鱼肉>鱼籽;鱼龄越大,体内富集的汞越多。对汞含量在0.12 ng～20.00 ng范围内呈线性关系,相关系数r=0.9999,最低检出限为0.04 ng。样品加标回收率为95.8%～104.4%,RSD为1.63%～2.92%。本方法与国标法无显著性差异。结论:本方法精密度和准确度较好,测汞时无需进行样品前处理,具有取样量少,简单、准确和高效等特点,能满足样品检测的要求。     

Metallic mercury induced tremor in rabbits and mercury content of the central nervous system

Fukuda, K. (1971).Brit. J. industr. Med.,28, 308-311. Metallic mercury induced tremor in rabbits and mercury content of the central nervous system. Tremor induced by metallic mercury was experimentally produced in rabbits by intermittent exposure to mercury vapour (average concentration of 4·0 mg/m³ for 6 hr/day on 4 days/week for 13 successive weeks). Two of six male rabbits exposed developed fine tremor and clonus in the fore- and hind-legs after 13 weeks' exposure. Electromyographic records showed typical grouped voltages accompanying the clonus (amplitude 0·3 to 1·0 mV, duration 20 to 30 ms, frequency 14 to 15 per second).

Activation analysis of the central nervous system showed mercury levels ranging from 0·8 to 3·9 μg/g wet tissue. The concentration in the cerebellum, the tegmentum, and the thalamus was significantly higher than in the remaining structures. The relationship between the tremor and the mercury content of the central nervous system is discussed and a positive causal relationship is suggested.

     

The mercury content of prehistoric fish

Seventeen samples of fish remains have been analyzed for mercury content by a neutron activation technique. Three samples were from Apple Creek, a Late Woodland site in central Illinois, which is dated shortly after A.D. 400. Five samples were from the Schultz site in Saginaw County, Michigan, a Middle Woodland location slightly older than Apple Creek. The remaining nine samples were from the pre‐Inca Chilca site located on the central coast of Peru. Freshwater species tested were Ictalurus punctatus (channel catfish), Pylodictis olivaris (flathead catfish), and Aplodinotus grunniens (drum). Five modern samples of these species from streams near Apple Creek were analyzed as a control. Peruvian salt water species have not yet been identified but are probably tuna and anchovy. Samples of the soil matrix in which the Chilca and Shultz specimens were found were also tested. Twelve of the prehistoric samples contained mercury in detectable quantities ranging from 0.014 to 9.463 ppm. Only one of the modern samples contained detectable mercury and neither soil sample had mercury in detectable amounts. The importance of archaeological data for establishing baselines for modern environmental evaluations is discussed. Implications of these data for modern disposal practices are considered.     

深海鱼类中汞含量的研究调查

采用原子荧光法对深海鱼类中的汞含量进行测定。方法具有准确可靠等优点,其检出限、精密度、国标溯源都在规定范围内。