Airborne Heavy Metals Research Articles

Heavy Metals in Epiphytic Mosses: An Experience in Florence

Abstract The epiphytic moss Hypnum cupressiforme has been used for passive monitoring of airborne heavy metals pollution by vehicular traffic in the urban area of Florence. Lead, cadmium, zinc and copper were determined by differential pulse anodic stripping voltammetry (DPASV). in the summer of 1993 about 30 samples were collected from the trunks of holm oak at the same height (1 metre) from the soil. Lead contents fall within the range of 0.02–1.08 μ moles g−1 (dry weight) and for this metal, the emission source may be attributed mainly to vehicular traffic in poorly industrialized urban areas. Some evaluations have been carried out about the employment of Zn/Pb molar ratio for characterizing airborne pollution in urban areas.

Comparison of moss and bark samples as biomonitors of heavy metals in a highly industrialised area in Izmir, Turkey

The moss, Hypnum cupressiforme and bark of the pine, Pinus brutia have been used for passive monitoring of airborne heavy metal pollution by an iron-steel mill of an industrialised area of Izmir, Turkey. Six metals, lead (Pb), cadmium (Cd), zinc (Zn), chromium (Cr), manganese (Mn) and iron (Fe) have been monitored using atomic absorption spectrometry. Between 26.2.1992 and 13.8.1992 samples were taken on five occasions at a distance of 0.25, 1.0 and 2.5 km from the mill. The results show an accumulation of all six metals, with differences between the moss and bark samples and a decrease in concentration with distance from the mill. The arithmetic means of the measured heavy metal concentrations in the moss, Hypnum cupressiforme, were always much higher than those in the bark of the P. brutia, indicating that the moss H. cupressiforme is more suitable than the bark of P. brutia for use in monitoring heavy metal pollution. The results show that the study area, within 2.5 km from the iron-steel mill, is heavily polluted.

Sorbents for the removal of airborne heavy metals from incinerator effluent

The effectiveness of inorganic alumino-silicate sorbents (alumina and kaolinite) to adsorb airborne lead and cadmium from the effluent stream of a simulated waste incinerator was studied. A 20 kW (68,000 BTU/h) flow reactor was used to achieve the temperature and residence times typical of a waste incinerator. Solutions containing lead or cadmium were introduced yielding airborne metals concentrations between 15 and 150 ppm. Gas samples were drawn into a particle impactor that collected the airborne particles and condensed phase metal aerosols, separating them into ten size ranges from 0.2 μm to greater than 10 μm. Metals to sorbent mass ratios between 0.03 and 1.56 were investigated. Scavenging efficiency increased as the ratio of sorbent to injected metal mass was increased. The scavenging efficiencies were as high as 76% for lead scavenged by kaolinite to as low as 14% for cadmium scavenged by alumina.

Sorbents for the removal of airborne heavy metals from the incineration of waste lubricating oils

Sorbents for the removal of airborne heavy metals from the incineration of waste lubricating oils

Comparison of biological collectors of airborne heavy metals near ferrochrome and steel works

The value of several biological monitors of the distribution of airborne Cr and Ni dust was studied in the vicinity of ferrochrome and stainless steel works. The following indigenous biomonitors were compared: the forest mosses Pleurozium schreberi and Hylocomium splendens, the epiphytic lichen Hypogymnia physodes, bark of Scots pine (Pinus silvestris), needle litter, earthworms (Dendrobaena octaedra) and moths (mainly Xylena vetusta). Results were compared and related to the heavy metal deposition estimated by the vertical snow sampling method. The representative sampling size at different pollution levels was investigated. In Cr it varied from 1 to 300 mg m−2 a−1. Of the biomonitors studied, the mosses showed most effective accumulation of heavy metals, their results having a clear relationship to the deposition and good replicability. The lichen gave almost as good results as the mosses. Both mosses and lichens collected heavy metals more effectively at low to moderate pollution loads than near the pollution source. The accumulation of heavy metals in bark was lower than in the mosses or lichen. The heavy metal content of earthworms indicated the degree of pollution well, but the replicability of the method was poor. The accumulation of heavy metals in moths was low.

An ion-exchange model of lead-210 and lead uptake in a foliose lichen; application to quantitative monitoring of airborne lead fallout

Lead, 210Pb and 210Po levels were determined in dated sequential growth of thalli of the foliose lichen Flavoparmelia baltimorensis from Great Falls and Plummers Island, Maryland. An ion-exchange model for uptake of Pb and 210Pb applied to these data is consistent with the experimentally measured Pb partition coefficient between water and lichen as well as the expected lead concentrations in rain. Lead-210/Polonium-210 activity ratios are significantly elevated in very young growth (<3 years old), as expected from model calculations. Retrospective Pb fallouts are computed which reflect the drop in gasoline lead emissions in the period sampled (1973–1986). With experimental determination of partition coefficients this methodology is a basis for retrospective quantitative monitoring of other airborne heavy metals using foliose lichens.

Distribution of airborne heavy metals as measured in the lichens Ramalina stenospora and Parmotrema praesorediosum in Baton Rouge, Louisiana

The lichens Ramalina stenospora and Parmotrema praesorediosum were collected from 30 stations in the greater metropolitan area of Baton Rouge, Louisiana and analyzed for Al, Cu, Fe, Zn, and Pb content. A univariate analysis of the data showed a significant difference between metal concentrations and sampling stations. When the stations were separated into two groups representing those in the industrial and urban zones, a discriminant analysis was over 90% successful in correctly assigning stations based solely on metal concentrations. No significant differences in metal concentration with species could be observed. Average metal concentrations for the two lichen species were used to construct contours and three-dimensional plots of metal distribution across the study area which clearly demonstrate the effects of the industrial zone on airborne metal levels.

Separation of anthropogenic and natural emissions of particulate heavy metals in the western Mediterranean atmosphere

Measurements of atmospheric particulate matter often include both natural and anthropogenic aerosols. The method proposed here allows the two contributions to be separated, and then, to be estimated. Sampling was carried out at Cape Ferrat, on the southeastern coast of France, during 1986 and 1987. The concentrations of Pb, Cu, Zn and Cd were measured using flameless atomic absorption spectrophotometry. The concentration data allowed us to establish, for each metal, an experimental probability density function, which was numerically analyzed. The numerical process is described in detail. The results show a good agreement between the calculated natural background aerosol at Cape Ferrat and natural concentration levels measured in several remote locations. Differences are explainable by the nature of the environment. Anthropogenic emissions are very high compared with natural inputs, because most of the airborne heavy metals in the western Mediterranean arise from human activities.

Heavy metal concentrations in a lichen of Mt. Rainier and Olympic National Parks, Washington, USA

It is commonly assumed that the larger National Parks in the United States are pristine places which can provide baseline environmental conditions for comparisons with more developed areas. However, recently it has been recognized that many National Pars are threatened by atmospheric pollution. Until 1985, a copper smelter at Tacoma, Washington, 50 km northwest of Mount Rainier National Park, Washington emitted 30 tons of lead annually, along with high levels of arsenic and other metals. Other nearby sources of airborne heavy metals include a coal-fired generating plant at Centralia, 80 km west of the Park, and automobiles within the Seattle-Tacoma metropolitan area 50-100 km to the northwest. Heavy metals are a potential threat because they may effect ecosystems by decreasing nutrient cycling rates and impairing overall productivity. The objective of this study was to test the hypothesis that an arboreal lichen (Alectoria sarmentosa) within Mt. Rainier National Park contained elevated levels of heavy metals from these sources. This lichen species was chosen because it is common throughout forested areas of the region. Olympic National Park was selected as an experimental control area because it is located on the relatively undeveloped Olympic Penisula west of Seattle-Tacoma.

Determination of metal deposition patterns by epiphytic lichens

The use of epiphytic lichens as quantitative monitors of airborne heavy metals needs a standardization of collection, analytical procedures and of data elaboration. Evidence is given of a patterned metal accumulation in lichens and for the foliose species, the analysis of the outermost edge of the thallus is suggested. Moreover, the raw concentrations of metals must be normalized to the earth's crustal abundance, as lichens entrap atmospheric particulates which are mostly constituted by soil and rock dust suspended by wind.

Isomerization of vinylidene olefins: R.C. Williamson; J.J. Harrison Chevron Research Co. U.S. 4,697,040, Sept. 29, 1987; Appl. Feb. 26, 1986

As airborne pollution is recognised as the single largest environmental health hazard in Europe, the necessity to develop effective systems for monitoring and reducing the level of air pollutants, becomes imperative. The paper describes a tested and implemented long-term biomonitoring system for airborne heavy metals at a national scale. Moss bags (Hylocomium splendens) were exposed in 142 monitoring stations designated in Romania, and the content of Pb, Cd, Ni and As was quantified using inductively coupled plasma mass spectrometry. The results revealed that the accumulation of heavy metals exceeded the established thresholds, marking high pollution levels in 8.8% of samples for As, in 5.63% samples for Cd, in 3.17% samples for Pb, and in 0.35% samples for Ni. The maximum heavy metal concentration was 113.77 mg kg−1 dry weight for Pb, 44.93 mg kg−1 dry weight for Ni, 14.68 mg kg−1 dry weight for As, and 3.88 mg kg−1 dry weight for Cd, with several overlaps for at least two metals, thus marking pollution hotspots. In order to process, summarise and communicate the obtained data, a software named BioMonRo has been developed as the core part of a complex monitoring and warning-informative system. The software is able to generate heavy metal pollution maps and specific reports, depicting the levels and patterns of distribution, which can be automatically sent to a number of interested recipients. The results show that the developed national system is functional, cost-effective, and could be successfully used for long-term monitoring of airborne heavy metals.

Correlations between the concentration of adenosine tri phosphate, chlorophyll degradation and the amounts of airborne heavy metals and sulphur in a transplanted lichen

The lichenRamalina duriaei (De Not.) Bagl. was transplanted to 12 biomonitoring sites during the period July1984–July 1985. The amounts of Ni, Cr, Cu, Zn, and Pb detected in the lichen thalli after the period of exposure, were compared with the ATP concentrations and the chlorophyll degradation in the same material. An inverse correlation between Pb, Cu, and ATP concentrations was found in the studied lichen. The degradation of chlorophylla to phaeophytina, as expressed by the ratio OD435/OD415 was inversely correlated with the amounts of Pb, Zn, Cu, and S in the lichen thallus. The amounts of the five heavy metals studied, were compared with those detected inR. duriaei transplanted to eight biomonitoring sites during the period 1979–1980. It is suggested that a regional increase in the amounts of Cr in the lichen exposed during the 1984/85 period is causally linked with emissions of Cr from the stacks of a new coal-fired power plant. The OD435/OD415 ratio was inversely correlated with the amounts of S in the lichen only in the material transplanted around the coal-fired power plant but not in the Tel Aviv area. No significant correlation was obtained between ATP and the amounts of S in the lichen.

Quantitative monitoring of airborne lead pollution by a foliose lichen

The potential use of lichens as quantitative monitors of airborne heavy metal pollution has been demonstrated by measurements of Po210, Pb, Cd, Zn, and V levels in sequential growth of the foliose lichen Pseudoparmelia baltimorensis from three localities in the greater Washington, D.C. area. Samples were dated using the growth rate measured by Lawrey and Hale (1977). Po210, Pb, and V increase with age in a given colony. Higher levels of Pb, V, Cd, and Zn are present in samples from the two more polluted sites. The retention of heavy metals is consistent with trapping by an ion exchange mechanism. Since Po210 is the daughter product of in situ decay of Pb210, accumulated from atmospheric fallout of known rate, its levels can be used to calculate trapping efficiencies of Pb and retrospective fallout rates. These rates are similar to published data from rural and urban areas.

Airborne heavy metal pollution in the environment of a danish steel plant

A survey of heavy metal deposition was carried out in the vicinity of a Danish steel plant. Bulk precipitation and transplanted lichen (Hypogymnia physodes (L.) Nyl.) were sampled at 12 stations in the environment before and after the production had been converted from open-hearth furnaces to electric-arc furnaces. The samples were analyzed for Cd, Cr, Cu, Fe, Mn, Pb and Zn.

The effect of coating polymers on accumulation of airborne heavy metals by lichens

Thalli of the fruticose lichen Ramalina duriaei (De Not.) Jatta collected at a rural unpolluted area were coated with synthetic coating polymers. The coated lichens were transplanted to a polluted site near a busy road intersection, for a period of 5 months. After the exposure period the content of Cu, Pb, and Ni in the thalli was measured. It was found that some of the coating polymers were effective in reducing the accumulation of Cu and Ni in the lichen thallus, but could not prevent the prevention of Pb. The coating treatment reduced chlorophyll degradation which occurred in the uncoated lichens.

Monitoring of Heavy Metals in Airborne Particles by Using Mosses Collected from the City of Zurich

Abstract The suitability of the moss Bryum argenteum as indicator plant of airborne heavy metals in urban environment has been examined. After extraction of the metals with 2N nitric acid, copper, cadmium, lead and zinc have been simultaneously determined by differential pulse anodic stripping voltammetry at the hanging mercury drop electrode. The method has been applied to determine the distribution of the respective metals in the Zurich city area. We have collected about 200 samples, uniformly spread over the area of Zurich, for this investigation. The results show clearly that the metals are considerably accumulated in the city compared to an uncontaminated region outside Zurich. Low correlation coefficients between metal concentrations indicate different emission sources for the various metals.

Characterization of airborne heavy metals within a primary zinc-lead smelting works

Characterization of airborne heavy metals within a primary zinc-lead smelting works

The effect of airborne heavy metals on automobile passengers in Germany

Inside passenger compartments of running cars, concentrations of lead, cadmium, copper, manganese, and iron are determined. Measurements inside different cars are performed on motorways and rural and urban roads. Analysis of the heavy metals is carried out by atomic absorption spectrometry. During urban driving, inside concentrations are in the same range as the concentrations measured on German motorways. Average concentrations of urban roads are slightly elevated. Average concentrations are lead 1.1 μgm −3, cadmium 0.002 μgm −3, copper 0.8 μgm −3, manganese 0.04 μgm −3, iron 2 μgm −3. Variations of concentration inside different cars are obvious. Elevated iron concentrations are produced by internal sources. A strong relationship of automotive lead concentrations to traffic and meteorological parameters is found. The comparison of inside concentrations to concentrations measured at a highly frequented motorway junction show that the penetration of airborne heavy metals to running cars is optimal.

Zinc and Cadmium Contents of Agricultural Soils and Corn in Northwestern Indiana

AbstractSoil and corn (Zea mays L.) leaf and grain samplings were conducted in northwestern Indiana to determine if airborne heavy metal particulates containing Cd and Zn from the northwestern Indiana industrial‐urban complex, situated on the south side of Lake Michigan, were contaminating soils and crops. Sampling in the region revealed no widespread metal contamination. Some metal enrichment had occurred on agricultural soils in Gary and East Gary, Ind. Corn leaf concentrations of Cd, Pb, and Zn fluctuated with sampling location, but grain Cd and Pb levels remained essentially constant at &lt;0.05 and &lt;0.4 µg/g, respectively. A comparison of Zn/Cd ratios in soils, and in corn leaves and grain, suggested that Cd was more actively accumulated in the corn plant but not the grain.Because of the limited acreage affected and the relatively low metal levels observed, no human or animal health problems are expected from harvested crops or silage.The use of log distance vs. log metal concentration in regression analysis showed that the limited metal contamination of agricultural soils was mainly in a southeasterly direction from the industrial‐urban area.

Use of msses as collectors of airborne heavy metals near a smelting complex

Moss bags are used as collectors of airborne heavy metals in the region surrounding the Zn and Pb smelting complex at Avonmouth, near Bristol, U.K. A land area of 660 km' is studied by exposure of 250 freshly prepared Sphagnum moss bags for 6-week periods. The results are presented as a series of squares computer drawn on maps of the area. Concentrations of metals in exposed mosses range from 4800 ppm Pb, 8200 ppm Zn and 200 ppm Cd, ≈ 700 m from the smelter, to insignificant levels in areas of Wales further than 15 km from the smelter. Metal concentrations are high within the zone of the prevailing winds from Avonmouth, where Pb and Cd values exceed background levels approximately 15-fold, as far as 15 km from the smelter.