水环境中痕量、超痕量元素汞的形态分析技术进展

水环境中汞的含量虽微,但其毒性甚大。水环境中汞的赋存形态不同,其毒性亦不同,汞总量的测定已不能充分揭示汞的毒性及其生物有效性。本文较为详尽的归纳总结了近年来水环境中汞形态分析的样品处理技术及其形态分析技术进展。     

Metabolic studies of Hg-203 on Chlamydomonas reinhardi

Sterile cultures of Chlamydomonas reinhardi, WT+, were treated with Hg-203 at 25 degrees C to identify probably formed volatile mercury compounds. Experiments were performed with living and dead cells under aerobic or anaerobic conditions, respectively, and the mercury concentration was measured in the system algae/nutrient medium. We found a timerelated decrease of mercury concentration in the cell suspension and the cell-free nutrient medium due to a reduction of Hg++ to Hg0, probably caused by extracellular enzymes; monomethyl or dimethyl mercury could not be detected.     

Le Dosage Spectrométrique du Mercure dans l'Air vers 1930

In the 1930s, atomic absorption spectroscopy replaced chemical methods for determining the amount of mercury in atmospheric air. The overall state of chemical analysis was favourable: physical instruments were moving into the chemical laboratory. This new method emerged from work in quantitative physics, and it met a need arising from the risk encountered by those who handled mercury. The new spectrometer, which originally functioned as a detector, also made precise and rapid quantitative determinations possible. This in turn encouraged industrialists to take out patents and make commercial use of the method after various improvements. This method is considered to be the ancestor of modern atomic absorption spectroscopy, which developed independently after 1960. The method developed in the 1930s could only be used for gaseous mercury, and it was not generalized as a method for quantifying other elements. The determination of mercury in air by atomic absorption spectroscopy was the first application of this technique; indeed, it was the only example of a specific use of atomic absorption. It was also part of the instrumental revolution.     

The dental amalgam issue. A review

Summary Using an interdisciplinary approach, the current position in the dental amalgam controversy and the potential impact of amalgam mercury on human health are reviewed. Aspects of materials science, corrosion, mercury exposure, toxicology, neurology and immunology are included.New data on mercury exposure from corroded amalgam fillings in vivo are presented. The exposure can reach levels considerably over known threshold limit values. Also, measurements of mercury absorption from intraoral air are presented. The vital importance of avoiding a galvanic amalgam-gold coupling is emphasized. The symptomatology of a disabled patient, who recovered after amalgam removal, has been included.It is concluded that discussion of the dental amalgam issue has suffered from the lack of an interdisciplinary approach. It would be wise to learn from the lesson of acrodynia, and consider amalgam mercury among other possible factors in neurological and immunological diseases of unclear etiology.     

The dental amalgam issue. A review

Using an interdisciplinary approach, the current position in the dental amalgam controversy and the potential impact of amalgam mercury on human health are reviewed. Aspects of materials science, corrosion, mercury exposure, toxicology, neurology and immunology are included. New data on mercury exposure from corroded amalgam fillings in vivo are presented. The exposure can reach levels considerably over known threshold limit values. Also, measurements of mercury absorption from intraoral air are presented. The vital importance of avoiding a galvanic amalgam-gold coupling is emphasized. The symptomatology of a disabled patient, who recovered after amalgam removal, has been included. It is concluded that discussion of the dental amalgam issue has suffered from the lack of an interdisciplinary approach. It would be wise to learn from the lesson of acrodynia, and consider amalgam mercury among other possible factors in neurological and immunological diseases of unclear etiology.     

Metabolic studies of Hg-203 onChlamydomonas reinhardi

Summary Sterile cultures ofChlamydomonas reinhardi, WT⁺, were treated with Hg-203 at 25°C to identify probably formed volatile mercury compounds. Experiments were performed with living and dead cells under aerobic or anaerobic conditions, respectively, and the mercury concentration was measured in the system algae/nutrient medium. We found a timerelated decrease of mercury concentration in the cell suspension and the cell-free nutrient medium due to a reduction of Hg⁺⁺ to Hg⁰, probably caused by extracellular enzymes; monomethyl or dimethyl mercury could not be detected.This work was supported by a grant of Österreichisches Bundesministerium für Gesundheit und Umweltschutz.     

Accumulation of mercuric selenide granules in the liver of Odontocetes (Mammifers, Cetacea): a possible method of detoxification of methylmercury by selenium]

In Mediterranean Cetaceans, concretions of pure mercuric selenide are found in the connective tissue of the liver. Their presence explains that high levels of mercury and selenium coexist with low level of methylmercury. The selenide could be produced parallel with demethylation of mercury, a process leading to the fossilization of mercury and partially of selenium under the form of a non biodegradable component.     

Natural selection for resistance to mercury pollution

Summary The survival under conditions of mercury pollution of two natural populations of the marine gastropodCerithium rupestre, derived from mercury-polluted and mercury-free sites, was tested in the laboratory. The results indicate a significantly higher survival rate for animals derived from the mercury-polluted site, in each of six repetitive experiments. We conclude that mercury resistance in marine organisms is reinforced in mercury polluted sites, presumably by natural selection for increased resistance. The evolution of metal tolerance in marine organisms may be as fast as that of metal tolerance in plants and the evolution of industrial melanisms in moths.     

Über Quecksilberspuren in Graphiten

Summary An investigation of 104 natural graphites shows in most of the samples a content <1 ppm mercury (Hg). An emissionspectrochemical method was used by the doubleare fromL. H. Ahrens. There are samples in the mine-ralogical collections with contents >10 ppm Hg, if metallic mercury is present in these collections.     

Chronic mercury vapor poisoning of aphids

Summary Exposure of green peach aphids,Myzus persicae (Sulz.), to an atmosphere containing mercury vapor resulted in a curtailment ofembryogenesis and larviposition by adults, and in the development by larvae and adults of a cuticular darkening of their legs, head capsule, antennae, cornicles and cauda. Mortality of affected larvae resulted from molting difficulties, particularly by last-instar alatiform female and male larvae. Greenbugs,Schizaphis graminum (Rond.), and pea aphids,Acyrthosiphon pisum (Harr.), responded to mercury vapor exposure in similar ways.     

La pression intrarénale chez l'homme

Summary The intrarenal pressure has been determined in man using a needle of the lumbal puncture type connected with a mercury manometer. Preliminary results in 8 patients with various renal diseases indicate no significant difference between cases of glomerulonephritis, acute anuria, chronic pyelonephritis and normal or almost normal kidneys. Our values are comprised between 23.5 and 41.5 mm of mercury, with an average of 34 mm. A possible correlation with the mean blood pressure is suggested by our data: intrarenal pressure =0.19 mean blood pressure +9.0. In one case, renal decapsulation had no influence on the intrarenal pressure.     

Über den Einfluss von Natriumsulfit,Natriumtellurit und Natriumselenit auf die Retention von Zink,Kadmium und Quecksilber im Organismus

Summary The influence of sodium sulfite, sodium tellurite and sodium selenite on the retention of zinc, cadmium and mercury in mice was studied. The retention of mercury was increased by sodium selenite and by sodium tellurite. The retention of cadmium was increased only by sodium selenite. Sodium sulfite did not influence the retention of metals studied. The retention of zinc was not influenced by any compounds used.     

Effect of ascorbic acid on biotransformation and modification of the toxicity of mercurials in goldfish (Carassius auratus)

Summary Ascorbic acid mediated a small but significant degradation of methylmercury to inorganic mercury in goldfish (Carassius auratus) and reduced the toxicity of mercuric chloride despite its substantial conversion into organic form. This investigation was supported by a grant from the Fishing Industry Research Account of the Australian Department of Primary Industry.     

The benthic red alga Ceramium ciliatum var. robustum (J.Ag.) G. Mazoyer is a remarkable biological indicator of littoral mercury pollution]

The study of mercury composition of red Algae Ceranium ciliatum var. robustum, comparatively with other marine organisms and considering its growth and the extent of pollution at various harvesting points: reveals that this seaweed constitutes a conspicuous biological indicator for the littoral mercury pollution.     

Observational defects in eighteenth-century British telescopes

Among the several remarkable properties of mercury is that it dissolves many of the metals (but not iron), forming amalgams. It was the recognition of the ready formation of gold and silver amalgams that led to the extraction of precious metals by the amalgamation method. In this article I trace some of the historical aspects associated with the development of the European amalgamation process, first devised by Ignaz von Born in the 1780s. In particular, I describe an international gathering of experts in mining and metallurgy which was held at Skleno in Slovakia in 1786, and the founding there of a society for mining sciences called ‘Die Societät der Bergbaukunde’.     

Study on the distribution of methyl-mercury (203Hg) by whole body autoradiography of macaque monkeys (Macaca irus)]

The distribution of methyl-mercury labelled with mercury-203 has been studied in Monkeys by whole body autoradiography technique. The mercury is rapidly absorbed. It is localized in all the body and mainly in well defined areas of the central nervous system.     

Inhibition of cadmium teratogenesis by a mercaptoacrylic acid (MFA)

The teratogenic effect of cadmium can be diminished by a number of mechanisms including zinc and pretreatment with cadmium and mercury. In this study, the oral administration of alpha-mercapto-beta-(2-furyl)-acrylic acid (MFA) protects against cadmium-induced malformations and embryonic death. This protection is probably mediated by the chelation of the cadmium ion rather than metallothionein (MT) synthesis.     

Methylmercury sexual dimorphism in the mouse

Summary 5–8 days after a single nontoxic dose of radioactive methylmercury chloride adult male mouse kidneys contain twice as much radioactive mercury per unit wet wt as do kidneys of similarly dosed adult females.This investigation was supported in part by NSF (RANN) grants (GI-30097 and AEN75-14889), by Program Project grant (ES-01248) and Center grant (ES-01247) from the NIEHS, and in part by the US Department of Energy at the University of Rochester Department of Radiation Biology and Biophysics and has been assigned Report No. UR-3490-1308.     

ATPase activity in mercury intoxicated eels

Summary Eels intoxicated by lethal doses of HgCl₂ accumulate mercury in their gills. Mercury inhibits the ouabainsensitive Na+K+ATPase activity of gills involving the rupture of the fish NaCl balance.The author wishes to express his sincere gratitude to Professor A. Disteche and Professor E. Schoffeniels for discussions during the investigation. This research was carried out in participation in the Belgian National Research and Development Program on the Environment-Water-Sea Project-Office of the Prime Minister-Interministerial Commission for Science Policy and Programmation.     

Steigerung der Genauigkeit bei astronomischen Durchgangsbeobachtungen

Summary The influence of the axis-inclination on the transit time can be eliminated by the observation of the star image reflected by a mercury level together with the influence of the variable collimation produced by a flexion of the axis.The hand-driving of the impersonal micrometer has been remplaced by a motor with an additional wheelwork permitting to move the micrometer independently from the motor mechanism. Both improvements increase the precision of the transit observations.