Heavy metals in some Chinese herbal plants

The concentrations of nine heavy metals, cadmium, cobalt, copper, iron, manganese, nickel, lead, zinc and mercury in 42 Chinese herbal medicinal plants were determined. Generally, all the samples studied had, relative to the other trace metals, higher concentrations of iron, manganese, and zinc. The concentration range of the metals determined was comparable to that in many of the East Asian vegetables and fruits. A few samples were found to contain relatively higher concentrations of the toxic metals such as cadmium, lead, and mercury. This was probably caused by contamination during air-drying and preservation.     

Toxic effect of heavy metals on cells isolated from the rat adrenal and testis

Summary Heavy metals including mercury, cadmium, cobalt, and copper (100 μM) exerted an adverse effect on the viability of isolated rat adrenal capsular (zona glomerulosa), adrenal decapsular (fasciculata and reticularis), and Leydig cells of the testis with mercury being the most potent. Due to the decreased cell viability there was a parallel reduction in corticotropin-stimulated, corticosterone production by adrenal decapsular cells and luteinizing hormone-stimulated testosterone production by Leydig cells. The results indicated a direct toxic action of these heavy metals on steroid-producing cell in the adrenal gland and the tectis. Other metals tested, including lead, zinc, aluminum, chromium, iron, nickel, and lithium, did not exert any deleterious effect on cell viability or hormone-induced steroidogenesis, in adrenal and Leydig cells when tested up to a concentration of 100 μM.     

Survey of metal tolerance in moderately halophilic eubacteria

The tolerance patterns, expressed as MICs, for 250 moderately halophilic eubacteria to 10 heavy metals were surveyed by using an agar dilution method. The moderate halophiles tested included 12 culture collection strains and fresh isolates representative of Deleya halophila (37 strains), Acinetobacter sp. (24 strains), Flavobacterium sp. (28 strains), and 149 moderately halophilic gram-positive cocci included in the genera Marinococcus, Sporosarcina, Micrococcus, and Staphylococcus. On the basis of the MICs, the collection strains showed, overall, similar responses to silver, cobalt, mercury, nickel, lead, and zinc. All were sensitive to silver, mercury, and zinc and tolerant of lead. The response to arsenate, cadmium, chromium, and copper was very heterogeneous. The metal susceptibility levels of the 238 freshly isolated strains were, in general, very heterogeneous among the four taxonomic groups as well as within the strains included in each group. The highest toxicities were found with mercury, silver, and zinc, while arsenate showed the lowest activity. All these strains were tolerant of nickel, lead, and chromium and sensitive to silver and mercury. Acinetobacter sp. strains were the most heavy-metal tolerant, with the majority of them showing tolerance of eight different metal ions. In contrast, Flavobacterium sp. strains were the most metal sensitive. The influence of salinity and yeast extract concentrations of the culture medium on the toxicity of the heavy metals tested for some representative strains was also studied. Lowering the salinity, in general, led to enhanced sensitivity to cadmium and, in some cases, to cobalt and copper. However, increasing the salinity resulted in only a slight decrease in the cadmium, copper, and nickel toxicities.(ABSTRACT TRUNCATED AT 250 WORDS)     

Survey of metal tolerance in moderately halophilic eubacteria.

The tolerance patterns, expressed as MICs, for 250 moderately halophilic eubacteria to 10 heavy metals were surveyed by using an agar dilution method. The moderate halophiles tested included 12 culture collection strains and fresh isolates representative of Deleya halophila (37 strains), Acinetobacter sp. (24 strains), Flavobacterium sp. (28 strains), and 149 moderately halophilic gram-positive cocci included in the genera Marinococcus, Sporosarcina, Micrococcus, and Staphylococcus. On the basis of the MICs, the collection strains showed, overall, similar responses to silver, cobalt, mercury, nickel, lead, and zinc. All were sensitive to silver, mercury, and zinc and tolerant of lead. The response to arsenate, cadmium, chromium, and copper was very heterogeneous. The metal susceptibility levels of the 238 freshly isolated strains were, in general, very heterogeneous among the four taxonomic groups as well as within the strains included in each group. The highest toxicities were found with mercury, silver, and zinc, while arsenate showed the lowest activity. All these strains were tolerant of nickel, lead, and chromium and sensitive to silver and mercury. Acinetobacter sp. strains were the most heavy-metal tolerant, with the majority of them showing tolerance of eight different metal ions. In contrast, Flavobacterium sp. strains were the most metal sensitive. The influence of salinity and yeast extract concentrations of the culture medium on the toxicity of the heavy metals tested for some representative strains was also studied. Lowering the salinity, in general, led to enhanced sensitivity to cadmium and, in some cases, to cobalt and copper. However, increasing the salinity resulted in only a slight decrease in the cadmium, copper, and nickel toxicities.(ABSTRACT TRUNCATED AT 250 WORDS)     

Biomonitoring of heavy metals by epiphytic lichen species in Black Sea region of Turkey

The heavy metal accumulation in epiphytic lichens along the Sarp-Samsun Highway in Black Sea Region of Turkey was analyzed by using energy dispersive X-ray fluorescence (EDXRF) and flame atomic absorption spectroscopy (FAAS) methods. The analysis showed that the lichen samples contained elevated concentrations of the following metals: titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, tin, barium, and lead. A strong positive correlation was observed between the lead concentration of the lichens and the traffic density.     

大肠杆菌拓扑异构酶I结合重金属的特性及功能影响

【背景】大肠杆菌拓扑异构酶Ⅰ(Escherichia coli topoisomerase I,E.coli TopA)在DNA复制、转录、重组和基因表达调控等过程发挥关键作用。研究表明E.coli TopA只有结合锌离子才具有活性,然而E.coli TopA能否结合其他金属离子尤其是重金属离子,以及结合其他金属后是否具有活性,目前仍不清楚。【目的】探究大肠杆菌拓扑异构酶Ⅰ是否结合环境中常见重金属离子,研究重金属离子结合E.coli TopA蛋白后对其活性的影响。【方法】在分别添加有锌、钴、镍、镉、铁、汞、砷、铬、铅、铜离子的M9基础培养中表达、纯化出E.coli TopA蛋白,并对纯化得到的蛋白用电感耦合等离子体质谱仪进行相应金属离子含量的测定;利用表达E.coli TopA锌指结构的突变体蛋白鉴定重金属离子的结合位点;通过体外超螺旋DNA松弛实验测定不同金属结合E.coli TopA的拓扑异构酶活性;通过测定蛋白内源性荧光推测不同金属结合E.coli TopA的空间构象差异。【结果】E.coli TopA在体内除了能结合锌和铁之外,还能够结合钴、镍、镉3种离子,但是不能结合汞、砷、铬、铅、铜离子。钴、镍、镉结合形式的E.coli TopA,每个蛋白分子最多可以结合3个相应的金属离子,他们与TopA蛋白的结合位点也是位于3个锌指结构域,而且每个锌指结构域结合1个金属离子。此外,E.coli TopA结合钴、镍、镉离子后,其DNA拓扑异构酶活性并未受到影响,可能是由于钴、镍、镉离子结合形式的E.coli TopA蛋白,其空间构象与锌结合形式相比并未发生显著变化。【结论】由于DNA拓扑异构酶在维持细胞正常生理功能中发挥关键作用,研究表明E.coli TopA的功能不会受到常见重金属的干扰(不结合或者结合后活性无影响),这也有可能是大肠杆菌在进化过程中产生的对抗环境中重金属离子毒害作用的一种自我保护和耐受机制,具有重要的生理意义。     

Excretion of metals into the rat intestine

The acute excretion of metals across the intestinal wall and by bile was investigated in vivo within 2 h after iv administration in rats. Heavy metals of biological interest, such as copper and zinc, and of toxicological importance, such as cobalt, cadmium, mercury, lead, and bismuth, as well as rubidium and strontium as examples of the alkali and alkali-earth metals were chosen. Most of the metals were excreted along a concentration gradient from blood into the intestinal lumen. Rubidium is the only metal excreted against a concentration gradient from blood into the lumen of both the small and large intestines. For all metals investigated, excretion into the small intestine exceeds that into the large intestine. Metal excretion by bile also occurred mainly along a concentration gradient from liver to bile, e.g., cobalt, zinc, mercury, rubidium, and lead, which is chosen as example of this group. Copper and strontium are excreted against a considerable concentration gradient from blood into bile. This holds true also for cadmium and bismuth in low doses.     

In vitro study on the interactive effects of heavy metals on catalase activity of Sarotherodon mossambicus (Peters)

The in vitro effects of individual heavy metal ions as well as their combinations on catalase activity were investigated. Copper was found to be the strongest inhibitor of catalase activity followed by mercury, iron, chromium and cadmium. Copper toxicity on catalase activity was reduced in the presence of all the other metal ions. However, the addition of cadmium, chromium, iron, manganese, lead to mercury and cadmium, iron, manganese, nickel, lead, zinc to chromium increased their inhibitory effects on catalase activity.     

Heavy metals in relation to the biology of the mummichog, Fundulus heteroclitus

Heavy metal levels of cadmium, copper, mercury, manganese, and zinc were examined in the mummichog, Fundulus heteroditus from industrialized and non-industrialized environments. With one exception, the environment with the highest trace metal in its waters, had the fishes with the highest metal concentration. Except for mercury, the concentration factor varied inversely with the metal concentrations of the fish and water, suggesting a possible regulatory mechanism for metals in the tissues of mummichogs from environments with high metal concentrations. There was an inverse relationship between standard length and concentrations of zinc, manganese, copper and cadmium in whole male and female fishes. The viscera contained significantly greater concentrations of these metals than somatic muscle tissue. There were also significant differences between males and females with respect to whole-body zinc and copper concentrations, but no sex differences for manganese and cadmium.     

Seminal plasma trace metal levels in industrial workers

This study compares the seminal plasma trace metal levels of hospital workers with groups of industrial workers in a petroleum refinery, smelter, and chemical plant. The metals measured were the essential metals (copper, zinc, nickel, cobalt, and manganese) and the toxic metals (lead, cadmium, and aluminum). The group mean±SE metal level for each group (50 subjects per group) was calculated, and the statistical significance of the group mean differences of the industrial groups with the hospital group (control) was determined by the Student’s t-test. The differences observed in the smelter group were increased copper and zinc (p≤0.001) and decreased nickel, cobalt, and manganese (p≤0.001,≤0.01). The refinery group differences were increased copper, zinc, and nickel (p≤0.001) but decreased cobalt and manganese (p≤0.001). The chemical group differences were increased zinc (p≤0.001) and decreased cobalt (p≤0.001). The seminal plasma levels of the toxic metals lead and aluminum were increased in each of the industrial groups (p≤0.001). Concurrent differences were (1) decreased accumulation of nickel, cobalt, and manganese in the smelter group, (2) decreased cobalt and managanese in the refinery group, and (3) only decreased cobalt in the chemical group.     

Incidence of antibiotic and metal resistance and plasmid Carriage in Aeromonas isolated from brown bullhead (latalurus nebulosus)

G.W. PETTIBONE, J.P. MEAR AND B.M. SAMPSELL. 1996. Seventy-four strains of Aeromonas were isolated from skin, intestine, kidney and liver of 16 brown bullhead ( Ictalurus nebulosus ). All strains demonstrated multiple antibiotic resistance (MAR) with most strains resistant to rifampin (97%), novobiocin (96%) and vancomycin (85%). The minimum inhibitory concentration of eight metals to selected strains of Aeromonas revealed an apparent toxicity of chromium > copper > cadmium > nickel > mercury > zinc > cobalt > lead, based on the percentage of isolates sensitive to each concentration of metal. Plasmid DNA was found in 36% (27) of the isolates and most plasmid-containing strains had multiple plasmids less than 12 kilobase pairs (kbp) in size. No relationship between plasmid content and antibiotic or metal resistance was found. Plasmid incidence in bacteria isolated from five fish indicated that plasmids were more likely to occur in strains isolated from kidney and liver than in strains isolated from skin and intestine.     

TRACE-ELEMENT TOXICITIES IN OAT PLANTS

Excessive amounts of nickel, cobalt, chromium, copper, zinc, manganese, molybdenum and aluminium in nutrient solutions supplied to oat plants in sand culture produce ( a ) chlorosis and ( b ) other symptoms specific to the element involved. The specific symptoms are distinct for each metal, although those of cobalt and nickel might be confused.
The toxic effects of nickel, cobalt, copper, zinc, manganese and molybdenum are associated with high concentrations of the element in the leaf tissue, but this is not always so with chromium and aluminium.
The toxic effects of nickel, chromium, copper and molybdenum are associated with a reduced nitrogen content of the plant. Nickel, cobalt, chromium, zinc and manganese increase the concentration of phosphorus in the tissue whilst aluminium decreases it, probably to a deficiency level.
Aluminium reduces the intensity of toxic symptoms produced by nickel—probably by reducing the uptake of nickel and phosphorus. Copper effectively reduces the leaf necrosis produced by nickel, but not the nickel content of the leaf tissue; it is suggested that one factor in nickel toxicity may be inhibition of one or more functions of copper. The other elements slightly increase chlorosis and some increase necrosis.
The order of activitjl of the elements in producing chlorosis is found to be Ni>Cu>Co>Cr>Zn>Mo>Mn. This order, which is related to that giving yield reduction and is similar to the order of stability of metal complexes, is discussed in relation to induced iron deficiency.     

Long-Term Sorption of Metals Is Similar among Plastic Types: Implications for Plastic Debris in Aquatic Environments

Concerns regarding plastic debris and its ability to accumulate large concentrations of priority pollutants in the aquatic environment led us to quantify relationships between different types of mass-produced plastic and metals in seawater. At three locations in San Diego Bay, we measured the accumulation of nine targeted metals (aluminum, chromium, manganese, iron, cobalt, nickel, zinc, cadmium and lead) sampling at 1, 3, 6, 9 and 12 months, to five plastic types: polyethylene terephthalate (PET), high-density polyethylene (HDPE), polyvinyl chloride (PVC), low-density polyethylene (LDPE), and polypropylene (PP). Accumulation patterns were not consistent over space and time, and in general all types of plastic tended to accumulate similar concentrations of metals. When we did observe significant differences among concentrations of metals at a single sampling period or location in San Diego Bay, we found that HDPE typically accumulated lesser concentrations of metals than the other four polymers. Furthermore, over the 12-month study period, concentrations of all metals increased over time, and chromium, manganese, cobalt, nickel, zinc and lead did not reach saturation on at least one plastic type during the entire 12-month exposure. This suggests that plastic debris may accumulate greater concentrations of metals the longer it remains at sea. Overall, our work shows that a complex mixture of metals, including those listed as priority pollutants by the US EPA (Cd, Ni, Zn and Pb), can be found on plastic debris composed of various plastic types.     

Effects of Metals on Streptomyces coelicolor Growth and Actinorhodin Production

Actinorhodin production by Streptomyces coelicolor was used as a model system to study the effects of metals on growth and polyketide synthesis in a streptomycete. Numerous metals were tested in cultures grown in liquid media. Mercury and cadmium were highly toxic, and copper, nickel, and lead were less so, but all tended to inhibit both growth and antibiotic synthesis to a similar extent. Unexpectedly, manganese, cobalt, zinc, and, to a lesser extent, chromium caused complex effects that in general resulted in some enhancement of growth yield but a reduction in antibiotic titers. These complex effects meant that cobalt, manganese, and zinc had lower 50% inhibitory concentrations for antibiotic yields compared with those for biomass. The physiologically active divalent cations calcium and magnesium were also tested. Calcium at high concentrations was particularly effective in reducing antibiotic titers and enhancing growth yields. By adding calcium at different phases of growth, it could be demonstrated that it was most effective in reducing the antibiotic yield when added during the early growth phase. Addition during the antibiotic-producing phase resulted in little reduction of final actinorhodin titers.     

Detection and Analysis of 12 Heavy Metals in Blood and Hair Sample from a General Population of Pearl River Delta Area

To detect the content of 12 heavy metals in blood and hair sample from a general population of Pearl River Delta area, and to analyze the influence of duration of residence, gender, age, smoking and drinking on the heavy metal content. Use inductively coupled plasma mass spectrometry to detect the content of 12 heavy metals lead (Pb), mercury (Hg), cadmium (Cd), aluminum (Al), arsenic (As), copper (Cu), chrome (Cr), manganese (Mn), nickel (Ni), zinc (Zn), tin (Sn) and antimony (Sb) in blood and hair samples of a total of 50 subjects from a general population, collected by multistage stratified cluster random sampling method. The geometric mean of heavy metal content in blood samples of general population (μg/L): blood aluminum 214.00; blood chrome 92.82; blood manganese 21.43; blood nickel 20.59; blood copper 0.67; blood zinc 11.50; blood arsenic 0.55; blood cadmium 2.45; blood tin 0.00; blood antimony 1.92; blood lead 158.84; and blood mercury 1.19. The geometric mean of heavy metal content in hair samples of general population (μg/g): hair aluminum is 84.65; hair chrome 0.00; hair manganese 2.44; hair nickel 0.61; hair copper 28.49; hair zinc 136.65; hair arsenic 0.75; hair cadmium 0.46; hair tin 1.04; hair antimony 0.05; hair lead 8.97; and hair mercury 0.69. Some heavy metals were correlated with duration of residence, gender, age, smoking and drinking. This was the first time that simultaneously detecting heavy metal content in blood and hair was used to analyze the internal heavy metal burden in resident population of Pearl River Delta area. These data can serve as reference for further research.     

Heavy metal and selenium concentrations in liver tissue from wild American alligator (Alligator mississippiensis) livers near Charleston, South Carolina

Liver samples from 33 wild American alligators (Alligator mississippiensis) livers from the Charleston, South Carolina, area were analyzed for arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), mercury (Hg), nickel (Ni), lead (Pb), and selenium (Se) concentrations. Alligators are top predators and are considered a good biomonitoring species for various toxins, including heavy metals. Alligators from other areas in the US have shown high concentrations of mercury and other heavy metals, but the Charleston area, which is highly industrialized, has not been investigated. We found wide variation in hepatic heavy metal and selenium concentrations among alligators. Length and sex did not show a strong relationship with any metal based on statistical analysis. However, cluster analysis revealed three groupings of alligators based on liver metal concentrations. Alligators with low Se:Hg ratios also had high concentrations of Hg. Due to the wide variation in metal concentrations among individual alligators, we postulate that individual diet and microhabitat usage could be the cause for this variation.     

The Correlation of Serum Trace Elements and Heavy Metals with Carotid Artery Atherosclerosis in Maintenance Hemodialysis Patients

Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima-media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64?±?0.11 vs 0.42?±?0.05, p?相似文献   

Influence of chosen elements on the dynamics of the cariogenic process

This prospective study comprised 140 natural crowns of the teeth extracted from 31 boys and 35 men, as well as 39 girls and 35 women. They were divided into two groups. Group I consisted of primary teeth and group II consisted of permanent teeth. In each group, two subgroups were distinguished: subgroup A containing teeth without caries and subgroup B comprising carietic teeth. Zinc, iron, copper, nickel, chromium, cobalt, lead, cadmium, selenium, and strontium were determined in the samples by using the total reflection X-ray fluorescence method. Significantly higher concentrations of zinc, iron, copper, nickel, selenium, and strontium were detected in the crowns of healthy primary and permanent teeth than in the crowns of the carietic primary and permanent teeth. The concentrations of chromium, cobalt, lead, and cadmium were significantly higher in primary and permanent teeth with caries than in the healthy ones. Judging from the obtained results, we think that lower concentrations of zinc, iron, copper, nickel, selenium, and strontium together with higher concentrations of chromium, cobalt, lead, and cadmium in the carietic primary and permanent teeth, in relation with the respective concentrations of those elements in healthy teeth, can be one of the caries risk factors.     

Heavy metal contamination of sediments in the Upper Connecting Channels of the Great Lakes

In 1985, sampling at 250 stations throughout the St. Marys, St. Clair, and Detroit rivers and Lake St. Clair — the connecting channels of the upper Great Lakes — revealed widespread metal contamination of the sediments. Concentrations of cadmium, chromium, copper, lead, mercury, nickel, and zinc each exceeded U.S. Environmental Protection Agency sediment pollution guidelines at one or more stations throughout the study area. Sediments were polluted more frequently by copper, nickel, zinc, and lead than by cadmium, chromium, or mercury. Sediments with the highest concentrations of metals were found (in descending order) in the Detroit River, the St. Marys River, the St. Clair River, and Lake St. Clair. Although metal contamination of sediments was most common and sediment concentrations of metals were generally highest near industrial areas, substantial contamination of sediments by metals was present in sediment deposition areas up to 60 km from any known source of pollution.Contribution 735 of the National Fisheries Research Center-Great Lakes, U.S. Fish and Wildlife Service, 1451 Green Road, Ann Arbor, MI 48105.     

A note on susceptibility of Branhamella catarrhalis to heavy metals

The susceptibility of 56 strains of Branhamella catarrhalis and ten Neisseria spp. to arsenate, silver, nickel, mercury, lead, cadmium, chromium, manganese, iron, cobalt and molybdenum was tested with an agar dilution technique. All but two strains of B. catarrhalis were resistant to multiple metal ions. There were not sufficient differences in susceptibility, however, to allow the development of a typing scheme based on resistograms. Heavy metal resistance in Branhamella was unrelated to beta-lactamase production. Neisseria spp. were more susceptible to metal ions than B. catarrhalis and this may form the basis of a simple diagnostic test.