Metal content of dandelion (Taraxacum officinale) leaves in relation to soil contamination and airborne particulate matter.

The global distribution of the common dandelion (Taraxacum officinale Weber, sensu lato; Asteraceae), along with its ability to tolerate a wide range of environmental conditions, make this 'species' a particularly attractive candidate to evaluate for its value as a biological monitor of environmental metal contamination. To examine the metal content of dandelion leaves in relation to environmental metal levels, the concentrations of eight metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were analyzed in leaf and soil samples collected at 29 sites in the mid-western United States differentially impacted by pollution. Sites were chosen primarily to cover a range of annual mean 24-h airborne particulate matter < or = 10 microm (hereafter, PM10) exposure, with PM10 levels varying from those found in isolated rural areas to levels typical of the most industrialized urban locations in the mid-western United States. A positive. significant correlation was detected between soil concentrations of each metal and measures of PM10 at a site, signifying that airborne particulate matter is a good indicator of soil metal contamination. Leaf concentrations of four of the eight metals (Cr, Mn, Pb and Zn) examined were found to increase significantly as the soil levels of these metals increased, but the percentage of the total variation explained by the relationship in these cases was generally low. This latter finding, along with the lack of a significant relationship between leaf and soil concentrations for the four other metals, indicate that the factors affecting metal absorption from the soil by dandelions are complex and that, aside from soil metal concentrations, other soil, plant and/or other environmental factors affect metal uptake. There was also no evidence that leaf metal concentrations were positively correlated with PM10. In addition, the concentrations of some metals (Cu, Fe, Mn, Pb and Zn) were significantly higher in leaves collected in the fall compared to those collected at the same sites in the spring. These findings suggest that dandelions may not be a particularly effective tool for quantifying levels of environmental metal contamination, at least on the scale of pollution typifying industrialized urban areas of the mid-western United States.     

Potential of dandelion (Taraxacum officinale) as a bioindicator of manganese arising from the use of methylcyclopentadienyl manganese tricarbonyl in unleaded gasoline

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese (Mn) compound currently added to unleaded gasoline in Canada. It has been suggested that the combustion of MMT containing Mn could cause various deleterious health effects in animals and humans at very high concentrations. This study evaluates the potential of dandelions (Taraxacum officinale) as bioindicators of Mn environmental contamination. Samples were picked at three different distances from a highway: a highly exposed site (E++), a lightly exposed site (E+) and a control site (E), located respectively at 10, 50 and 100 m. The total Mn, Mg, Ca, Al, Fe and Zn concentrations were measured in the soils and in the plants (flower, stem, leaves and root) by neutron activation analysis. Exchangeable Mn was measured in soils by atomic absorption spectrophotometry. Mn concentrations of the different parts of the plant and exchangeable Mn in soils were not correlated with distance from the roadway and, thus, do not seem to be a sensitive indicator of Mn contamination. Soil Mn concentrations were correlated with distance from the roadway. This suggests the hypothesis that the environmental fate of Mn from MMT sources could be associated with an increased total Mn in soil but does not lead to an increase in exchangeable Mn.     

Accumulation of copper, lead, manganese and iron by field populations of Hydrodictyon reticulatum (Linn.) Lagerheim.

The potential of 'water-net' Hydrodictyon reticulatum to accumulate copper, lead, manganese and iron was determined in seven polluted water bodies having different physicochemical characteristics. The lead accumulation was linearly related with ambient concentration whereas in case of copper, manganese and iron it was maximum at lowest ambient level of metals. Investigations on response of alga to various concentrations of test metals under single metal treatments revealed that the algal cells are saturated at high equilibrium concentration of greater than 0.5 (lead), greater than 2.5 (copper and iron) and greater than 5.0 (manganese) mg/l. Alkaline pH favoured accumulation of these metals under field conditions. Alga showed high concentration factor (Cf) for all the metals both under field and laboratory conditions. However, Cf value was higher in case of manganese and iron in natural populations. Results indicate the possibility of using this alga in waste water treatment programmes.     

Diagenetic remobilization of manganese, iron, copper and lead in anoxic sediment of a freshwater pond

The diagenetic remobilization of manganese, iron, copper and lead in anoxic sediment of a freshwater pond, T Reservoir, Japan has been examined in an in situ submerged chamber system, through the interstitial water and sediment analyses. Manganese was released continuously from the sediment into the overlying water during the experiment, whereas iron was released from the sediment abruptly after the 2nd day of the experiment. The steep vertical concentration gradients of manganese and iron were observed in the interstitial water. The release of manganese and iron from the sediment is due to the dissolution of ferro-manganese oxides and hydroxides in the surface sediment under anoxic condition. In contrast to manganese and iron, copper and lead were not released from the sediment during the experiment, and their concentrations in the interstitial water were not significantly different from the values of the overlying water. The results show that the diagenetic remobilization of copper and lead in the sediment is negligibly small. It is likely that copper and lead are fixed into the sediment by some process other than the formation of sulfides.     

Effects of manganese, copper and lead on Selenastrum capricornutum and Chlorella stigmatophora

Algal assays were conducted to observe the responses of Selenastrum capricornutum and Chlorella stigmatophora to the metals manganese, copper and lead, added singly or in combination to both artificial media and natural waters. A 50% reduction in the total algal cell volume of Selenastrum in standard algal assay medium (SAAM) occurred by the addition of either 3.1 mg manganese 1⁻¹ 85 μg copper 1⁻², or 140 μg lead 1⁻¹. For Chlorella grown in 28 ppt artificial seawater plus full SAAM nutrients, the corresponding numbers were 50mg manganese 1⁻¹, 70 μg copper 1⁻¹ or 700 μg lead 1⁻¹. Of the metals tested, only lead was found in higher concentrations in urban and agricultural runoff than at least one of these levels.Theoretical considerations show that a product model is a more reasonable reference for no-interaction than an additive model for experiments in which toxic metals are added in combination. Combination experiments, in which any combination of the three metals act at the same time, indicate (1) synergism between manganese and copper, (2) antagonism between manganese and lead, and (3) antagonism between copper and lead. As to the manganese-lead interaction, it is shown that the lead-induced inhibition of cell division is offset, partially for Selenastrum and completely for Chlorella by the addition of manganese.     

The effect of surfactants on the extraction-atomic absorption spectrophotometric determination of copper, iron, manganese, lead, nickel, zinc cadmium and cobalt

Nine surfactants representing pure cationic, anionic and non-ionic detergents, three industrially prepared detergents. sodium pyrophosphate. sodium tripolyphosphate, and a soap were investigated for their effect on the extraction-atomic absorption spectrophotometric determination of copper. iron, manganese and lead. Some results are also given for nickel, zinc, cadmium and cobalt. Cations were extracted into 10 ml of MIBK as APDC chelates. To Avoid emulsion formation, maximum concentration of LAS was 1 mg 1⁻¹, and for formulated and non-ionic detergents and washing powders it was 5 mg 1⁻¹.A standard addition procedure was used to obtain correct results for copper and nickel. Two extractions of iron, cobalt and lead, and one extraction of manganese, zinc and cadmium gave a recovery of 100 ± 5%. Soap gave high recoveries for iron and copper. NTA in concentrations up to 25 mg l⁻¹ did not interfere. EDTA in concentrations up to 25 mg l⁻¹ interfered with iron and nickel determinations, but the addition of 3 mg of aluminium removed the EDTA interference in the determination of copper, manganese, lead, zinc, cadmium and cobalt.For the determination of trace metals in polluted natural waters the amount of 4% APDC was increased to 10 ml and for manganese to 25 ml. An addition of 3 mg aluminium as nitrate after the addition of buffer with subsequent 20 min reaction time is required for the determination of all eight metals by the recommended procedures. The effect of humic acid was also investigated.     

Effect of fats, mineral oils and creosote on the extraction—atomic absorption determination of copper, iron, lead and manganese in water

The effect of five mineral oils, two fats and creosote on the extraction—atomic absorption spectrophotometric determination of copper, iron, lead and manganese in water was investigated. Pure mineral oils, fats and creosote gave 100±15% recovery, but soluble oil gave low results for copper and iron. At a soluble oil concentration of 12.5 mg 1⁻¹, the recoveries of copper and iron were, respectively 41 and 72%.     

Use of Polytrichum formosum (moss) as a passive biomonitor for heavy metal pollution (cadmium, copper, lead and zinc)

After sampling over regular intervals from 1985 to 1987 the heavy metals Cd, Cu, Pb and Zn were quantitatively determined by atomic emission spectrometry/inductively coupled plasma in above-ground parts of the moss Polytrichum formosum (Hedw.). All metals present a typical summer-winter oscillation (seasonal variation), which is much greater than the "inter-stand" variation of Polytrichum formosum within the forest ecosystem under investigation. To obtain comparable results on a regional or global scale it is suggested to collect all samples of Polytrichum formosum for biomonitoring purposes in the last week of September.     

The sorption of copper(II), manganese(II), zinc(II) and arsenic(III) onto human hair,and their desorption

Human hair has been studied in relation to sorption from aqueous solutions of Cu²⁺, Mn²⁺, Zn²⁺ and AsO₃^3?. At an equilibrium concentration of 0.3 μg ml^?1 the sorptions are relatively low for Mn (1.1 μg g^?1) and As (0.1 μg g^?1), and higher for Zn (10 μg g^?1) and Cu (35 μg g^?1). But only in the case of copper is the sorption significant relative to the indigenous levels of the elements in the hair. The greater sorption of Cu²⁺ may be correlated with better binding to the hair fibre, probably both electrostatically and to the sulphur in the keratin. There appears to be at least three modes of attachment, or three mechanisms of attachment of Cu²⁺ to the hair. An inter-element effect was observed, where Cu²⁺ severely inhibits the sorption of Zn²⁺ and Mn²⁺. Also the total sorption of Cu²⁺ is reduced on zinc or manganese-treated hair. Some comments are made regarding the results and the problems of exogenous contamination of human hair.     

Determination and speciation of copper and lead in sediments of a Mediterranean river (River Tenes, Catalonia, Spain)

Total concentrations of Cu and Pb and the speciation of these metals in sediments of the River Tenes are studied in order to establish the extent to which they are polluted and their capacity of remobilization. Five samples taken along the river were analyzed, major components of the sediments were studied using XRF and total Pb and Cu content were determined by AAS. In order to test the accuracy of the digestion methods used (triacid attack with nitric, perchloric and hydrofluoric acids or diacic attack with nitric and hydrochloric acids) for the determination of total trace metal, a standard reference material was also analyzed. Triacid attack is proposed to obtain good results. The results show a highly polluted area (1556 mg kg⁻¹ Cu and 1555 mg kg⁻¹ Pb) in the last sampling site analyzed. For metal speciation, the sequential scheme of Tessier et al. was used. From the results obtained, it can be concluded that Cu content in non-residual fraction is bonded mainly to organic matter, whereas non-residual Pb is mainly associated to iron and manganese oxides.     

Iron, zinc, copper, manganese and magnesium in malignant lymphomas

Lymph node and spleen tissues involved in malignant lymphomas were analysed for iron, manganese, copper, zinc and magnesium by atomic absorption spectrophotometry. The levels of iron are found to be significantly lower in the case of Hodgkin's lymphoma compared with non-Hodgkin's lymphoma and normal lymph nodes. However, they are elevated in Hodgkin's lymphoma when compared with the normal value for spleen tissues. Magnesium is significantly higher in lymph nodes of non-Hodgkin's lymphoma compared with Hodgkin's lymphoma and normal values, but is not altered significantly in spleen tissues. The distribution of the other elements examined is not altered significantly in malignant lymphomas. The importance of the in situ levels of these elements to NMR imaging is discussed.     

The lead, copper and zinc content of tree rings and bark. A measurement of local metallic pollution.

Analysis of samples of wood taken from different tree rings for lead by atomic absorption spectrometry showed that there was little correlation between the sample site or ring age and air borne lead concentrations. However, the concentration of lead in tree bark at several sites was particularly sensitive to traffic flow at that site. The concentration of lead, zinc and copper in the tree bark decreased with increased distance from the road and with height above the ground. The method offers a simple technique for effectively tracing atmospheric metal concentrations.     

Quantities and associations of lead, zinc, cadmium, manganese, chromium, nickel, vanadium, and copper in fresh Mississippi delta alluvium and New Orleans alluvial soils

The topic of this study is the effect of anthropogenic metals on the geochemical quality of urban soils. This is accomplished by comparing the metal contents and associations between two alluvial soils of the lower Mississippi River Delta, freshly deposited alluvial parent materials and alluvial soils collected from a nearby urban environment. Fresh alluvium samples (n = 97) were collected from the Bonnet Carré Spillway. The urban alluvial soil samples (n = 4026) were collected from New Orleans and stratified by census tracts (n = 286). The Spillway samples tend to have less Pb and Zn than generally noted for the baseline of natural soils. Except for Mn and V, Spillway alluvium contains significantly less metal than urban soils. For Spillway samples, the median metal content (in microg g(-1)) is 4.7 Pb, 11.1 Zn, 0.7 Cd, 164 Mn, 0.8 Cr, 3.9 Ni, 3.2 V, and 3.9 Cu. For urban soils, the median metal content (in microg g(-1)) is 120 Pb, 130 Zn, 3.2 Cd, 138 Mn, 2.1 Cr, 9.8 Ni, 3.8 V, and 12.7 Cu. Metal associations also differ between Spillway alluvium and urban alluvial soils. Fresh alluvium correlation coefficients between individual metals vary from 0.87 to 0.99 (P < 10(-13)) except for Cr which ranges from 0.57 to 0.68 (P < 10(-7)). The urban soil correlation coefficients for metals and the index value are 0.40-0.98. In urban soils, Pb, Zn, Cr, and Cu are dominant metals and highly associated, with a correlation coefficient ranging from 0.83 to 0.98 (P < 10(-25)). Their strong association justifies the use of GIS to map the integrated soil metal index (sum of the medians of metals by census tract) of New Orleans. Although also positively correlated (0.40-0.68, P < 10(-10)), Cd, Mn, Ni and V differ in their distribution in the city compared to Pb, Zn, Cr and Cu. Overall, significantly higher metal values occur in the inner city and lower values occur in outlying areas. The human health impact of the mixture of metals is not well understood. This study provides empirical data about the mixture and distribution of metals in New Orleans alluvial soils. Given common technical development, especially of traffic flows in cities, similar patterns of soil metals are expected for all US cities and probably international cities as well. Primary prevention of urban metal accumulations is necessary to enhance and sustain the development of urban culture.     

Adsorption of copper, lead and cobalt by activated carbon

The phenomena of lead, copper and cobalt adsorption by activated carbon from aqueous solution was studied in detail. Laboratory studies were conducted to evaluate and optimize the various process variables (i.e. carbon type, solution pH, equilibrium time and carbon dose). A quantitative determination of the adsorptive capacity of activated carbon to remove these metals was also determined.Significant differences were found in the ability of different types of activated carbons to adsorb lead, copper and cobalt from aqueous solution. Solution pH was found to be the most important parameter affecting the adsorption. It was found that there was practically no adsorption of lead, copper and cobalt by activated carbon below a well defined solution pH value for each metal. This critical solution pH value was found to be lower than the pH value associated with the formation of hydrolysis products. Of the ten commercially available activated carbons evaluated in these experiments, Barney Cheney NL 1266 was found to adsorb the largest percentage of lead, copper and cobalt. The adsorption of any single metal (lead, copper and cobalt) was hindered by the presence of the other metals; the metals apparently competed for adsorption sites.     

The effect of graded doses of cadmium on lead,zinc and copper content of target and indicator organs in rats

Eleven groups of inbred Wistar rats, five males and five females in each group, received graded doses of CdCl₂, from 0–25 ppm, in the drinking water from conception until sacrifice at the age of ten weeks. The Pb, Zn and Cu levels of various indicators and target organs were recorded by atomic absorption spectrophotometry. Cd concentrations above 5 ppm caused a significant increase in Zn content of kidneys, liver, spleen, heart and adrenal glands in most of the experimental groups, and in addition a significant positive correlation between Cd and Zn in the same tissues. With concentrations above 10 ppm, Zn contents of epiphyses and diaphyses decreased significantly, and through all groups there was a significant negative correlation between Zn and Cd in diaphysis. This local Zn deficit may cause a retarded growth of long bones. Cd supply resulted in a significant decrease in Zn content of incisors and molars, but did not significantly affect the Cu content. Neither were Zn nor Cu concentrations in hair affected. Cd supply led to a significantly increased storage of Cu in liver, spleen, heart and skeletal muscle and a positive correlation between Cd and Cu content in the same tissues. Cd administration caused a significant decrease of Pb concentrations in molars, hair, kidney cortex, heart, skeletal muscle and adrenal glands in several of the experimental groups, and also a significant negative correlation between Pb and Cd content of molars, hair, kidney cortex, liver and heart. This can be a result of decreased uptake, increased excretion or changes in the distribution pattern of Pb.     

Fabrication of polymer-supported nanosized hydrous manganese dioxide (HMO) for enhanced lead removal from waters

In the current study, a new hybrid adsorbent HMO-001 was fabricated by impregnating nanosized hydrous manganese dioxide (HMO) onto a porous polystyrene cation exchanger resin (D-001) for enhanced lead removal from aqueous media. D-001 was selected as a support material mainly because of the potential Donnan membrane effect exerted by the immobilized negatively charged sulfonic acid groups bound to the polymeric matrix, which would result in preconcentration and permeation enhancement of lead ions prior to their effective sequestration by the impregnated HMO. HMO-001 was characterized by scanning electron micrograph (SEM), transmission electron micrograph (TEM), and X-ray diffraction (XRD). Lead adsorption onto HMO-001 was dependent upon solution pH due to the ion-exchange nature, and it can be represented by the Freundlich isotherm model and pseudo-first order kinetic model well. The maximum capacity of HMO-001 toward lead ion was about 395 mg/g. As compared to D-001, HMO-001 exhibited highly selective lead retention from waters in the presence of competing Ca²⁺, Mg²⁺, and Na⁺ at much greater levels than the target toxic metal. Fixed-bed column adsorption of a simulated water indicated that lead retention on HMO-001 resulted in a conspicuous decrease of this toxic metal from 1 mg/L to below 0.01 mg/L (the drinking water standard recommended by WHO). The exhausted adsorbent particles are amenable to efficient regeneration by the binary NaAc-HAc solution for repeated use without any significant capacity loss. All the results validated the feasibility of HMO-001 for highly effective removal of lead from contaminated waters.     

Arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in feathers of Black-legged Kittiwake (Rissa tridactyla) and Black Oystercatcher (Haematopus bachmani) from Prince William Sound, Alaska

Arsenic, cadmium, chromium, lead, manganese, mercury and selenium were analyzed in the feathers of Black-legged Kittiwakes (Rissa tridactyla) from Shoup Bay in Prince William Sound, Alaska to determine if there were age-related differences in metal levels, and in Black Oystercatchers (Haematopus bachmani)) from the same region to determine if there were differences in oiled and unoiled birds. Except for mercury, there were no age-related differences in metals levels in the feathers of kittiwakes. Kittiwakes over 13 years of age had the highest levels of mercury. There were no differences in levels of metals in the feathers of oystercatchers from oiled and unoiled regions of Prince William Sound. Except for mercury, the feathers of oystercatchers had significantly higher levels of all metals than those of kittiwakes. Levels of mercury in kittiwake feathers (mean of 2910 ng/g [ppb]) were within the range of many species of seabirds reported for other studies, and were generally below adverse effects levels.     

Removal of copper,nickel, cobalt and manganese from aqueous solution by kaolinite

The removal of some heavy metals such as Mn(II), Co(II), Ni(II), and Cu(II) from aqueous solution is studied using a raw kaolinite. The sorption of these metals on kaolinite conformed to linear form of Langmuir adsorption equation. Langmuir C(m) constants for each metal were found as 0.446 mg/g (Mn), 0.919 mg/g (Co), 1.669 mg/g (Ni), 10787 mg/g (Cu) at 25 degrees C, respectively. Also, kinetic and thermodynamic parameters such as enthalpy (deltaH), free energy (deltaG) and entropy (deltaS) were calculated and these values show that adsorption of heavy metal on kaolinite was an endothermic process and the process of adsorption was favoured at high temperatures.     

Effect on exhaust emissions by the use of methylcyclopentadienyl manganese tricarbonyl (MMT) fuel additive and other lead replacement gasolines

This paper examines the potential effects on car exhaust emissions of a range of alternative lead replacement gasolines in the context of south European countries such as Greece. The main objective of this study was to assess the effects on emissions from non-catalyst passenger vehicles by the substitution of leaded ('super') gasoline with Euro95 unleaded enriched with the additive MMT or other alternative to leaded gasoline fuels. Regulated emissions, two non-regulated pollutants and vehicle performance were measured on two catalyst-equipped and two conventional, non-catalyst vehicles. It was found that there was no measurable effect on regulated emissions (CO, HC and NO(x)) and on fuel consumption by the introduction of the lead replacement fuels for both catalyst and non-catalyst cars. In the case of the non-catalyst car, the shift from leaded to unleaded gasoline was associated with an increase in benzene and formaldehyde emissions, a trend probably attributable to the increased aromatics content of the lead replacement fuels.     

Concentrations of copper, zinc and lead in the Sydney rock oyster, Saccostrea commercialis (Iredale and Roughley) from the Georges River, New South Wales.

Copper, zinc and lead were analysed from samples of non-commercially grown Sydney rock oysters collected from the Georges River estuary in spring 1987. The results, when compared with previous data from 1975, indicated a marked increase in the concentration of copper (up to 40%) and zinc (up to 300%). For several sites, the recommended (National Health and Medical Research Council) levels for copper and zinc (70 micrograms g-1 and 1000 micrograms g-1 respectively) were exceeded. There appears to be a decrease in the concentration of lead since 1975. The gradient of increasing copper and zinc concentrations with increasing distance upstream from the mouth of the estuary reported in 1975 could not be statistically validated. A significant correlation was found between copper and zinc loadings in the oysters. It was noted that data collected in 1975 were based on commercially grown oysters. The use of commercially grown oysters, rather than indigenous oysters, to examine interaction of contaminant load and distance upstream, is complicated as commercial oysters are moved within the estuary and between estuaries to maximise growth potential.