Metal Accumulation Patterns Research Articles

Patterns of trace metal accumulation in Swedish marine nemerteans

Patterns of trace metal accumulation in Swedish marine nemerteans

Bioaccumulation of cadmium, lead, copper, and zinc in successive developmental stages of Lymantria dispar L. (Lymantriidae, Lepid)?a life cycle study

The forest pest insect Lymantria dispar L. (gypsy moth) was reared on an artificial diet contaminated independently with four metals at two different concentrations (2 and 10 μg/g Cd, 4 and 20 μg/g Pb, 10 and 50 μg/g Cu, 100 and 500 μgg Zn). Whole body metal concentrations were determined in each larval stage, pupae, imagoes, and F1 generation first instars and also of the corresponding exuviae, headcapsules, and faeces. The pattern of metal accumulation in successive developmental stages was metal and concentration (Cu, Zn) specific. Pb was barely assimilated by the larvae (concentration factor <0.4), whereas the concentration factors for the other metals were generally above 1 (the highest concentration factors determined for instars were: 3.5 (Zn), 4 (Cd), 5 (Cu)). All metals were eliminated via the meconium to a certain extent. In all groups, metal content was positively correlated with L. dispar larval weight. These relationships were also concentration dependent. F1-generation first instar larvae showed significantly higher metal contamination than controls, reflecting the metal burdens of the parental generation.

Accumulation patterns of trace metals in freshwater isopods in sediment bioassays—Influence of substrate characteristics, temperature and pH

Asellus aquaticus (L.) was exposed in microcosms to littoral sediments from Lake Ketelmeer (River Rhine estuary) and from a control site in order to study effects of substrate characteristics, temperature and pH on the kinetics of trace metal accumulation. Elimination patterns were studied in parallel experiments with preloaded animals kept on control sediment or in test water. In a 50 day semistatic bioassay at three different temperatures (5, 10 and 20°C) and two pH levels (7.3 vs 8.1) a highly significant accumulation of Cd, Pb, Cu and Zn by the isopods was observed. No net uptake was recorded in animals kept on control substrates. The most marked accumulation by Asellus was noted for the non-essential trace metals Cd and Pb. Element-specific effects of sediment characteristics and temperature were encountered on sediment-water partitioning (Cd, Cu and Zn) and on accumulation and elimination kinetics (Cd, Cu and Pb). No significant effects were observed for the different pH levels. Accumulation of Cd and Cu increased significantly with temperature. Pb concentrations in animals exposed at 20°C were found to be significantly lower compared to other temperatures. The accumulation of Zn appeared to be unaffected by temperature. Two distinct elimination patterns were observed. Elimination of Cd and Cu was absent at the higher temperatures. A slight elimination of these metals was recorded only in some of the treatment groups at 5°C. Both elements seemed to be stored in stable body compartments. A relatively rapid elimination, not affected by temperature, was observed for Pb (biological) half-life: 8–15 days) and Zn (half-life: 21–44 days); above the control sediments Asellus maintained a Zn concentration of c. 100–150 μgg −1 (dry wt). Several explanations for the observed accumulation patterns and temperature effects are presented. The results indicated that freshwater isopods could be suitable organisms for bioassays and biological monitoring studies on the bioavailability of sediment-bound trace metals.

Amelioration of copper and nickel toxicity by iron plaque on roots of rice (Oryza sativa)

Deposition of an iron oxide plaque or coating on roots of rice (Oryza sativa L. cv. M-201 84 Biggs) ameliorated the toxic effects of copper (Cu), nickel (Ni), and Cu + Ni on plant growth and affected patterns of metal uptake and accumulation. Plaque was formed on plants during 24 h in an anaerobic solution containing 20 mg ∙ L−1 iron at pH 5.5. Subsequently two additional coatings were deposited after new growth of roots. Plants were grown hydroponically in one-quarter strength Hoagland's solution and exposed to Cu (0.5 mg ∙ L−1), Ni (2.0 mg ∙ L−1), or Cu + Ni; exposure to metals lasted 21 – 45 days. At the end of the experimental period growth was estimated as total biomass, dry weight of root, dry weight of shoot, length of leaf, and length of root. After harvesting, Fe, Cu, and Ni concentrations in plaque were measured using a dithionite–citrate–bicarbonate extraction, and internal Fe, Cu, and Ni concentrations were measured in roots and leaves using atomic absorption spectrophotometry. Formation of the palque did not affect growth of plants in control solutions. When exposed to Cu, plants with plaque had significantly larger biomass, dry weight of roots, dry weight of leaves, and growth increments of root and leaf than plants without plaque. When exposed to Ni, plants with plaque had signifiantly higher increment in leaf growth than plants without plaque. When exposed to Ni + Cu, plants with plaque had significantly higher biomass than plants without plaque. Toxic symptoms were not observed on plants with plaque grown with excess copper, while all other plants exposed to metals showed chlorosis, necrosis, or both. Metals were detected on the surface of roots, whether plants were allowed to develop a plaque or not. Cu, Ni, and Fe were concentrated in plaque and in roots. Lower concentrations of Cu and Ni were found in leaves of plants with a plaque than in plants without plaque. Comparisons of concentrations of Fe, Cu, and Ni with those of other species grown under field conditions are made. Key words: rice, iron plaque, toxicity of Cu and Ni.

Accumulation of heavy metals from polluted soils by the earthworm, Lumbricus rubellus: Can laboratory exposure of ‘control’ worms reduce biomonitoring problems?

This paper compares the patterns of metal (Pb, Zn, Cd, Cu) accumulation in nine populations of the epigeic earthworm, Lumbricus rubellus, native on metalliferous soils, with the patterns of metal accumulation in batches of L. rubellus sampled from an uncontaminated site and maintained on the nine contaminated soils for 31 days under laboratory conditions. The primary findings were: (1) the Pb, Zn and Cd concentrations in the ‘native’ worms were significantly higher in most cases than in the ‘introduced’ worms; (2) multiple regression analyses indicated that the relationships between tissue and soil metal concentrations were similar for ‘native’ and ‘introduced’ worms; (3) high soil organic matter content reduced the bioavailability of Pb, but low pH increased Pb bioavailability. It was concluded that, although no phenotypic evidence of metal-tolerant ecotypes was obtained, the exposure of earthworms from uncontaminated soils to contaminated soils under laboratory conditions can provide meaningful integrative data concerning metal bioavailability in soils which, for biomonitoring purposes, often present formidable sampling problems.

CONCENTRATIONS OF METALS (Cu, Pb, Cd, Zn, Ca) IN SIX SPECIES OF BRITISH TERRESTRIAL GASTROPODS NEAR A DISUSED LEAD AND ZINC MINE

Heavy metal concentrations in 6 terrestrial slug species inhabiting a disused Pb/Zn mine site were measured by atomic absorption spectrophotometry. Differences in metal accumulation patterns were such that the species could be ranked in order of overall metal accumulation capability: Arion hortensis < Deoceras reticulatum < Milax budapestensis < Arion ater < Deroceras caruanac < Arion subfuscus. Species belonging to the same genus were widely separated by this simple ranking scheme. The results are discussed in the context of inter-species competition and resource partitioning, and cautionary comments are made concerning the utility of slugs as biomonitors of terrestrial heavy metal pollution.

ACCUMULATION OF SELECTED TRACE METALS IN SOILS OF URBAN RUNOFF SWALE DRAINS1

ABSTRACT: Field investigations were conducted at three sites in the Washington, D.C., area to detect the accumulation patterns of the trace metals, cadmium, copper, lead and zinc in the soils of roadside grassed swale drains that had been receiving urban stormwater runoff. Two sites were residential areas and one site was an intensively used highway. The research results seem to indicate that the use of swale drains to control urban stormwater runoff had few harmful effects to fine textured soils with respect to the study metals. With the exception of zinc, typical roadside patterns of decreasing metal concentrations with increasing distance from roads were observed for the upper 5 cm of study soils. Zinc accumulated in residential grassed swales due to leachate from galvanized curverts. Sampling to a depth of 60 cm revealed no evidence of subsurface trace metal enrichment in the study swales. Although the percentage of soil zinc in leachable form was as high as 20 percent of total zinc concentrations, the other study metals had small leachable components. Leachable lead was always less than 1 percent of the total lead.

Accumulation patterns of heavy metals in forest mosses from the south-west region of Nigeria

The accumulated levels of the metals, Pb, Cd, Cu, Ni, Zn, Mn and Fe were determined in forest mosses from south-west Nigeria. Distinct gradients were observed only with Pb and Zn, and a small zone of random contamination with Cu was identified in parts of the east and the south-east. This contamination was possibly a result of the use of copper-based fungicides and pesticides in cocoa farms in the area. The levels of the metals are compared with those in forest mosses in some other parts of the world.

Comparative study on amounts of trace elements in the solitary ascidians, Ciona intestinalis and Ciona robusta

1. 1. The closely related ascidian species, C. intestinalis and C. robusta have different accumulation patterns of metals. 2. 2. The former had a higher amount of vanadium and lower amounts of iron and manganese in most tissues than the latter. 3. 3. However, there was little difference in nitrogen and phosphate contents.

ACCUMULATION OF SELECTED TRACE METALS IN SOILS OF URBAN RUNOFF DETENTION BASINS1

ABSTRACT Field investigations were conducted at three sites in the Washington, D.C., area to detect accumulation patterns of the trace metals, cadmium, copper, lead, and zinc in the soils of urban stormwater detention basins. The research results seemed to indicate that the use of detention basins to control urban stormwater runoff had few harmful effects to fine textured soils with respect to the study trace metals. Although the trace metals, especially lead and zinc, were found to accumulate in the surface soils of the basins, little significant downward movement of metals in the soil profiles had occurred. Accumulations of metals in the surface soils appeared to be a function of microtopography and the resultant residence time of standing water. The fractions of trace metals that were present in a leachable form in surface soils and stormwater solids were small, with median values ranging from 7.7 percent of the total concentration for Cd to 0.01 percent for Pb.

Heavy-metal accumulation in the annual rings of balsam fir Abies balsamea (L.) Mill.

The accumulation patterns of Pb, Cu and Zn in annual rings and the growth of balsam fir Abies balsamea (L.) Mill. growing at non-polluted (control) and polluted forest sites are compared. Results show (1) a gradual decrease in metal accumulation from older to younger annual rings at the non-polluted site; (2) this pattern is drastically reversed for the younger rings at the polluted site from the time pollution loading began; and (3) a marked decrease in the growth of annual rings corresponding to the reversal of metal accumulation pattern.

Lead, Zinc and Copper Analyses of British Blanket Peats

(1) Analyses of three heavy metals (lead, zinc and copper) in surface peat layers, dated peat profiles and surface vegetation samples from fifteen British sites are discussed in the context of the movement of heavy metals in the peat system, and the present-day and historical patterns of heavy metal accumulation in humified, slow-growing blanket peat. (2) The concentrations of heavy metals in the surface peat samples provide a basis for the division of the fifteen sites into two groups-'low-background' and 'high-background' sites-reflecting the current urban/industrial status of the sites. Significant regressions were found of the concentrations of lead and copper in the surface peat layers on the loge population of the nearest big town to each site. (3) Dating schemes for five peat profiles were produced by pollen analysis. Generalized linear dating-plots were obtained by correlating individual pollen features with documentary evidence of tree-planting and agrarian or industrial activity. Estimated rates of net peat accumulation varied from 1 cm in 5-5 years to 1 cm in 40 years. (4) Recent rates of heavy metal deposition were calculated for six sites where the rate of peat accumulation had been estimated from pollen analytical/radiocarbon dating. The deposition rates derived from the peat analyses for lead and copper were similar to those obtained by other workers from conventional deposition gauges. The rates for zinc were very much lower than the published figures, suggesting considerable losses by leaching of this metal from the peat surface. (5) Variation in the concentrations of heavy metals was examined in three dated peat profiles. The distribution of lead in a 'low-background' profile apparently reflects national trends in production and utilization of lead during the last seven or eight centuries, while well-marked peaks in the lead profiles at two 'highbackground' sites are shown to correspond well with the documented history of the fortunes of the local lead mines and smelters. The patterns of zinc and copper were less well-defined. (6) In surface samples of present-day blanket bog vegetation consisting of Calluna vulgaris and Eriophorum vaginatum, the concentration of lead was higher in the older, more persistent or decaying plant components, whereas the concentration of zinc was higher in the younger, actively metabolizing organs. In a Sphagnum papillosum sample, the distribution of lead was fairly homogeneous in different age-segments, but the concentration of zinc was higher in the lower, older segments. It is suggested, therefore, that zinc is more mobile within plants and more susceptible to leaching. (7) Two neighbouring peat profiles were analysed for macrofossils. Apparent anomalies in the distribution of zinc were attributed to the differences in the vegetational composition of the profiles. (8) In a laboratory experiment the greater part of the lead and zinc and one-third of the copper in peat blocks was removed by leaching for 24 h with a chelating agent (EDTA). Lead and copper were virtually unaffected by leaching with sulphuric and acetic acids, whereas the zinc was substantially leached by the sulphuric but not by the acetic acid. It is concluded that leaching of lead and copper through peat is unlikely, but that zinc in surface peat is susceptible to leaching, especially in areas

Patterns of trace metal accumulation in crayfish populations.

Patterns of trace metal accumulation in crayfish populations.

Relation Between Total Body Weight and Concentrations of Manganese, Iron, Copper, Zinc, and Mercury in White Muscle of Bluefish (Pomatomus saltatrix) and a Bathyl-Demersal Fish Antimora rostrata

Concentrations of mercury (Hg) increased significantly with size (P &lt; 0.001) in white muscle of bluefish (Pomatomus saltatrix) and a bathyl-demersal fish Antimora rostrata but concentrations of manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn) either remained constant or decreased. These results indicate that fish residing in two different ecosystems in the Atlantic Ocean may be in a steady state with their environment with respect to Mn, Fe, Cu, and Zn but not Hg. The observed variations in accumulation patterns of trace metals in muscle of these two species as a function of size are discussed.