Phosphorus Amendment Reduces Hematological Effects of Lead in Mallards Ingesting Contaminated Sediments

Lead poisoning of waterfowl has been reported for decades in the Coeur d’Alene River Basin (CDARB) in Idaho as a result of the ingestion of lead-contaminated sediments. This study was conducted to determine whether the addition of phosphoric acid to sediments would reduce the bioavailability and toxicity of lead to mallards (Anas platyrhynchos) as related to adverse hematological effects and altered plasma chemistries. Mallards received diets containing 12% clean sediment (controls) or 12% sediment from three different CDARB sites containing 4520, 5390, or 6990 μg/g lead (dw) with or without phosphoric acid amendment. Blood lead concentrations were significantly higher in all CDARB treatment groups and ranged from geometric mean values of 5.0 μg/g for the first two sites to 6.2 μg/g for the third site. With amendments, all blood lead concentrations became 41% to 64% lower. Red blood cell ALAD activity was depressed by 90% or more with lead-contaminated sediment from all sites and did not differ with amended diets. Free erythrocyte protoporphyrin (FEP) concentrations were elevated by contaminated sediment from all sites. Amendment decreased the elevations in FEP by as much as 80%. Hematocrit values and hemoglobin concentrations were lower for all lead site sediments by as much as 30% for site 3. Plasma enzyme activities for ALT, CK, and LDH-L were elevated by as much as 2.2-fold, and plasma creatinine concentration was 1.7-fold higher for site 3 sediment. Amendments restored hematocrit, hemoglobin, and plasma enzyme activities so that they did not differ from controls. Although amendments of phosphorus substantially reduced the bioavailability of lead and alleviated many of the adverse hematological effects, lead concentrations in the blood of mallards fed the amended sediments were still above those believed to be harmful to waterfowl under the present conditions.     

Bioavailability of Lead and Cadmium in Soils Artificially Contaminated with Smelter Fly Ash

This study evaluated lead and cadmium uptake by maize grown on soils artificially spiked with smelter fly ash and possible changes in chemical fractionation of these metals in the soil. Maize grown on the less contaminated soil (1,466 mg Pb kg⁻¹; 19 mg Cd kg⁻¹) did not exhibit any chlorosis/necrosis symptoms or lower biomass yields compared to the control. The addition of the chelating agent ethylenediaminetetraacetic acid increased lead uptake by maize, as expected. Neither maize cultivation nor the addition of the chelant influenced significantly the chemical fractionation of lead and cadmium in the soil during the experiment.     

Toxicity Assessment of Contaminated Sediments after Dredging

No abstract available.     

Statistical Evaluation of the Bioavailability of Heavy Metals from Contaminated Soils to Vegetables

No abstract available.     

Toxicity of Lead-Contaminated Sediment to Mallards

Because consumption of lead-contaminated sediment has been suspected as the cause of waterfowl mortality in the Coeur d'Alene River basin in Idaho, we studied the bioavailability and toxicity of this sediment to mallards (Anas platyrhynchos). In experiment 1, one of 10 adult male mallards died when fed a pelleted commercial duck diet that contained 24% lead-contaminated sediment (with 3,400 μg/g lead in the sediment). Protoporphyrin levels in the blood increased as the percentage of lead-contaminated sediment in the diet increased. Birds fed 24% lead-contaminated sediment exhibited atrophy of the breast muscles, green staining of the feathers around the vent, viscous bile, green staining of the gizzard lining, and renal tubular intranuclear inclusion bodies. Mallards fed 24% lead-contaminated sediment had means of 6.1 μg/g of lead in the blood and 28 μg/g in the liver (wet-weight basis) and 1,660 μg/g in the feces (dry-weight basis). In experiment 2, we raised the dietary concentration of the lead-contaminated sediment to 48%, but only about 20% sediment was actually ingested due to food washing by the birds. Protoporphyrin levels were elevated in the lead-exposed birds, and all of the mallards fed 48% lead-contaminated sediment had renal tubular intranuclear inclusion bodies. The concentrations of lead in the liver were 9.1 μg/g for mallards fed 24% lead-contaminated sediment and 16 μg/g for mallards fed 48% lead-contaminated sediment. In experiment 3, four of five mallards died when fed a ground corn diet containing 24% lead-contaminated sediment (with 4,000 μg/g lead in this sample of sediment), but none died when the 24% lead-contaminated sediment was mixed into a nutritionally balanced commercial duck diet; estimated actual ingestion rates for sediment were 14% and 17% for the corn and commercial diets. Lead exposure caused elevations in protoporphyrin, and four of the five mallards fed 24% lead-contaminated sediment in a commercial diet and all five fed the contaminated sediment in a corn diet had renal intranuclear inclusion bodies. Lead was higher in the livers of mallards fed 24% lead-contaminated sediment in the corn diet (38μg/g) than in the commercial diet (13 μg/g). Received: 9 April 1998/Accepted: 21 October 1998     

Contaminated and Natural Lead Environments of Man

Eight cases of conjoined twins have been observed to occur among more than 5,000 embryonating zebra fish eggs that had been submitted to elevated water temperature several hours after fertilization. A naturally occurring epidemic of conjoined twins in salmon roe is described, and the principles which may underly the formation of conjoined twins in selected vertebrates and mammals are discussed. It is thought that environmental rather than genetic causes are usually at work in their production.     

Bioaccumulation and Bioavailability of Mirex from Lake Ontario Sediments

No abstract available.     

A Laboratory Assay to Assess Avoidance of Contaminated Sediments by the Freshwater Oligochaete Lumbriculus variegatus

Responses of benthic organisms to contaminated sediments in the laboratory historically have been assessed as survival, growth, and reproduction. However, these responses do not include behavioral aspects of organisms, which also can influence species distribution and abundance in benthic communities. This study documents avoidance behavior of the freshwater oligochaete Lumbriculus variegatus to contaminated sediments in the laboratory, utilizing a chamber specifically built to facilitate the measurement of this response. A number of field-collected sediments from sites with known contamination, several of which exhibited little or no toxicity in standard tests examining growth and/or survival, were evaluated. The oligochaetes exhibited marked avoidance to many of the sediments, indicating the potential utility of this assay in identifying effects of contaminated sediments on benthic community structure. Received: 29 September 1997/Accepted: 6 January 1998     

Impact of Soil and Dust Lead on Children's Blood Lead in Contaminated Areas of Sweden

The impact of lead in soil and dust on blood lead concentrations in young children (i.e., 1–5 y of age, N = 202) and the risk of health effects were investigated in an urban and a mining area of Sweden. Blood, soil, and indoor dust, as well as information on lead-exposure factors, were collected. The blood lead concentrations (total range = 9–77 μmlg/l) the authors measured indicated a low risk for lead-induced health effects. Lead in soil (i.e., < 10–5,000 μmlg/g) and in dust (i.e., < 1–316 μmlg/g) had little effect on blood lead concentrations, given the present conditions and present concentration range—especially in the mining area. Urban children had significantly higher blood lead concentrations than children in the mining area, despite higher concentrations of lead in soil in the mining area. In the urban children, blood lead concentrations were influenced by parental smoking and lead in dust at day-care centers.     

Cytochrome P450-Dependent Enzymes and Oxidant-Mediated Responses in Rainbow Trout Exposed to Contaminated Sediments

Hatchery-reared immature rainbow trout (Oncorhynchus mykiss) were exposed to different concentrations (2 and 4 liters) of contaminated sediment taken from a site receiving unbleached pulp mill effluents. The fish were held in aquaria and sampled three times during an experimental period of 21 days. The monooxygenase activity, measured as the deethylation of 7-ethoxyresorufin (EROD activity), increased three- to fourfold in the exposed fish relative to controls. The increase was not dependent on exposure concentration. Cytochrome P450IA1, the EROD catalyst, demonstrated proportional induction in the 2-liter exposed fish. However, exposure to 4 liters sediment strongly induced P450IA1 and did not reflect EROD activity. This may suggest inhibition of P450IA1 activity by the amount of chemicals discharged from pulp mills. UDPglucuronosyl-transferase increased at one stage of the experimental period, while glutathione S-transferase remained unchanged. Amounts of total glutathione in blood, liver, and muscle were slightly increased by exposure to contaminated sediments, but hepatic enzyme activities of superoxide dismutase and catalase were not affected. In conclusion, monooxygenase activities appear to be a sensitive tool in the monitoring of sediment toxicity.     

Field Evaluation of Lead Effects on Canada Geese and Mallards in the Coeur d'Alene River Basin, Idaho

Hatch year (HY) mallards (Anas platyrhynchos) in the Coeur d'Alene (CDA) River Basin had higher concentrations of lead in their blood than HY Western Canada geese (Branta canadensis moffitti) (geometric means 0.98 versus 0.28 μg/g, wet weight). The pattern for adults of both species was similar, although geometric means (1.77 versus 0.41 μg/g) were higher than in HY birds. HY mallards captured in the CDA River Basin in 1987 contained significantly lower lead concentrations in their blood than in 1994–95 (0.36 versus 0.98 μg/g); however, some very young mallards were sampled in 1987, and concentrations in adults were not significantly different in 1987, 1994, or 1995 (1.52, 2.07, 1.55 μg/g, respectively). Both species in the CDA River Basin in 1994–95 showed significantly reduced red blood cell delta-aminolevulinic acid dehydratase (ALAD) activity compared to the reference areas: Canada geese (HY −65.4 to −86.0%, adults −82.3%), and mallards (HY −90.7 to −95.5%, adults −94.1%). Canada goose goslings were divided into size classes, and the two smaller classes from the CDA River Basin had significantly elevated free erythrocyte protoporphyrin (protoporphyrin) levels compared to the reference area (15.2× and 6.9×). HY and adult mallards both had significantly elevated protoporphyrin (5.9× and 7.5×). Recognizing that interspecific differences exist in response and sensitivity to lead, it appears (at least for hemoglobin and hematocrit) that Canada geese were more sensitive to lead than mallards, i.e., adverse hematologic effects occur at lower blood lead concentrations. Only Canada geese from the CDA River Basin, in spite of lower blood lead concentrations, had significantly reduced mean hemoglobin and hematocrit values. No euthanized Canada geese (all HYs) from CDA River Basin were classified as clinically lead poisoned, but 38 Canada geese found dead in the CDA River Basin during a concurrent study succumbed to lead poisoning between 1992 and 1997. Only 6 (15.8%) of these 38 contained ingested lead shot, which contrasts greatly with the 75–94% incidence of ingested lead shot when mortality was due to lead shot ingestion. Lead from other contaminated sources (i.e., sediments and vegetation) in the CDA River Basin was strongly implicated in most Canada goose deaths. Based on the 31 live mallards and Canada geese collected in the CDA River Basin, which were representative of the live populations blood sampled only, the prevalence of subclinical and clinical lead poisoning (as determined by liver lead concentrations, excluding birds with ingested lead shot) was higher in mallards: subclinical (4 of 8, 50% HYs and 6 of 11, 55% adults); clinical (0% HYs and 4 of 11, 36% adults), with less data available for Canada geese (only 1 of 9, 11% HYs marginally subclinical). The clinically lead-poisoned mallards had extremely high concentrations of lead in blood (2.69–8.82 μg/g) and liver (6.39–17.89 μg/g). Eight mallards found dead in the CDA River Basin during a concurrent study were diagnosed as lead poisoned, and only one (12.5%) contained ingested lead shot, which again strongly implicates other lead sources. The finding of dead lead poisoned Canada geese together with the high percentage of live mallards classified as subclinically or clinically lead poisoned, in combination with the low incidence of ingested lead shot causes us concern for both of these species, which live in association with lead-contaminated sediment in the CDA River Basin. Received: 31 July 1999/Accepted: 8 December 1999     

Bioavailability of Polycyclic Aromatic Hydrocarbons (PAHs) from Surficial Lake Erie Sediments

No abstract available.     

Assessment of Toxicity to Earthworm Eisenia fetida of Lead Contaminated Shooting Range Soils with Different Properties

Bulletin of Environmental Contamination and Toxicology - The objective of the study was to evaluate the toxicity of trace elements to earthworms (Eisenia fetida) in recreational and military...     

Oral Bioavailability of Lead and Arsenic from a NISTStandard Reference Soil Material

The oral bioavailability of soil contaminants is measured using in vitro or in vivo techniques. Current efforts in our laboratory are focused on the comparisons of in vitro methods for bioavailability estimation with the presently employed in vivo techniques, such as animal models. We present a comparison of two techniques for oral bioavailability estimation: in vitro dissolution and in vivo rat feeding using a standard reference soil. Lead (Pb) and arsenic (As) were chosen because of the range of concentration in this soil as well as the large historical database of bioavailability values for these metals. Metal solubility was measured using a sequential soil extraction in synthetic analogues of human saliva, gastric and intestinal fluids. The soluble metal was defined as the bioaccessible fraction. Oral bioavailability of Pb and As was measured in Sprague Dawley rats by determining metal levels in the major organs and urine, feces, and blood at 1-, 2-, and 3-day time points. Extractions to determine bioaccessibility yielded a gastric component of 76.1% and 69.4% for Pb and As, respectively, and intestinal components were 10.7% and 65.9%. The oral bioavailability of the standard reference soil was 0.7% and 37.8% for Pb and As, respectively. Bioaccessibility was greater than bioavailability for both metals in both gastrointestinal compartments. Although Pb had the highest soil concentration of the selected metals, it was the least bioavailable, while As was highly available in both the in vitro and in vivo method. These types of data allow for an in vitro–in vivo comparison of a soil whose metal concentrations have been certified and validated. Received: 13 March 2000/Accepted: 27 June 2000     

Evaluation of Fish Health Status and Histopathology in Gills and Liver Due to Metal Contaminated Sediments Exposure

Health status of freshwater fish, Cirrhina mrigala was studied by qualitative and quantitative histopathological analysis, alterations in frequency/prevalence percentages (%) and histological alteration indices (HAI) in response to metal contaminated sediments of the River Ravi aquatic ecosystem. Histo-structures of gill and liver samples of fish were analyzed and comparison between the degree of damage of the alterations in fish organs was performed after exposure to metal contaminated sediments for 7, 14 and 28 days under semi-static water renewal bioassays. Histopathological studies revealed marked histological alterations in the gills and liver of exposed fish as compared to normal tissue structure observed in control fish. The frequency and prevalence percentages observed in 28-day exposed fish were significantly higher as compared to 7- and 14-day exposed fish. The order of frequency and prevalence percentage for gills and liver of exposed fish was as: 28-day?>?14-day?>?7-day. The highest prevalence percentages recorded were 83 and 80% as focal area of necrosis in gill and liver, respectively, after 28-day exposure. The lowest prevalence percentage observed in 7-day exposed Cirrhina mrigala was dilation of sinusoids (17%).     

Desorption and Bioavailability of Spiked Pentabromo Diphenyl Ether and Tetrachlorodibenzo(<Emphasis Type="Italic">p</Emphasis>)dioxin in Contaminated Sediments

The relationship between desorption kinetics and bioavailability of sediment-associated 2,2',4,4,5' pentabromo diphenyl ether [(14)C] (BDE-99) and 2,3,7,8 tetrachlorodibenzo(p)dioxin [(3)H] (TCDD) was examined in the contaminated sediments. The desorption kinetics were measured in a sediment-water suspension using Tenax extraction, and bioaccumulation was examined by exposing Lumbriculus variegatus (Oligochaeta) to BDE-99 and TCDD spiked sediment in a 14-day kinetic study. Both chemicals had a high affinity to the finest particle size fraction (<20 microm) and the large, very slowly desorbing fraction (58-75%). The biota-sediment accumulation factors ranged between 1.9 and 4.4 for BDE-99 and between 1.4 and 2.8 for TCDD. The chemical outflux from the rapidly desorbing fraction and influx into organisms shows the connection between desorption and bioavailability. Despite this, normalization to the rapidly desorbing fraction was unable to reduce differences in bioavailability estimates between the chemicals. Thus, it is evident that chemical extraction in the mixed system (Tenax tubes) does not fully describe the bioavailable fraction that worms face in stagnant sediments in a similar way for all chemicals. However, when all desorbing domains were included in the calculation, the difference between the chemicals disappears. Desorbing fractions were also able to reduce variability in the biota-sediment accumulation factors between the tested sediments when organic carbon-based sediment chemical concentrations were modified by the desorbing fractions.     

Innovative Intersectoral Approach Reduces Blood Lead Levels of Children and Workers in Romania

Abstract

With the support of the U.S. Ageney for International Development (USAID), an intersectoral approach involving the community, governmental and nongovernmental agencies, and the management of the local copper smelting plant succeeded in reducing the blood lead levels of plant workers and of young children living in the vicinity of a copper smelter, Zlatna, Romania. Specifics of the collaborative effort, which attracted enthusiastic responses from all participants, are provided.