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Archives of Environmental Contamination and Toxicology (v.58, #2)
Permeation of Herbicidal Dichlobenil From a Casoron Formulation Through Nitrile Gloves by Shane S. Que Hee; Hanaa Zainal (pp. 249-254).
The aim of this study was to measure permeation of the herbicide dichlobenil in Casoron 4G through disposable and chemically protective nitrile gloves using an American Society for Testing and Materials-type permeation cell and a closed-loop system employing two different solvents (hexane and water) and two different challenge situations (aqueous emulsion and solid formulation). Capillary gas chromatography–mass spectrometry was used for quantification purposes. The chemically protective glove did not allow any permeation up to 8 h for the solid-formulation and water-collection challenges, but permeation was detected in all other challenges. The disposable glove allowed the most permeation, and the solid-formulation challenge with water collection necessitated that a dichlobenil equivalent be calculated because of the presence of its hydrolysis degradation product 2,6-dichlorobenzamide. Permeation from the solid formulation was detectable by hexane collection for both the disposable and chemically protective gloves and by water collection for the disposable glove. It was concluded that hexane-solvent collection was not valid for the disposable glove at 4 and 8 h of permeation in the solid Casoron challenge or for the aqueous emulsion challenge at 8 h relative to the water-collection solvent data. The hexane-solvent collection for the chemically protective glove was valid for the 8-h solid-formulation challenge but not for the 8-h aqueous-solution challenge. All water-solvent collections were valid; however, dichlobenil usually permeated the gloves.
Development of a Sample Preparation Method for the Analysis of Current-Use Pesticides in Sediment Using Gas Chromatography by Dongli Wang; Donald P. Weston; Yuping Ding; Michael J. Lydy (pp. 255-267).
Pyrethroid insecticides have been implicated as the cause of sediment toxicity to Hyalella azteca in both agricultural and urban areas of California; however, for a subset of these toxic sediments (~30%), the cause of toxicity remains unidentified. This article describes the analytical method development for seven additional pesticides that are being examined to determine if they might play a role in the unexplained toxicity. A pressurized liquid extraction method was optimized to simultaneously extract diazinon, methyl parathion, oxyfluorfen, dicofol, fenpropathrin, pyraclostrobin, and indoxacarb from sediment, and the extracts were cleaned using a two-step solid-phase extraction procedure. The final extract was analyzed for the target pesticides by gas chromatography/nitrogen–phosphorus detector (GC/NPD), and gas chromatography/electron capture detector (GC/ECD), after sulfur was removed by shaking with copper and cold crystallization. Three sediments were used as reference matrices to assess method accuracy and precision. Method detection limits were 0.23–1.8 ng/g dry sediment using seven replicates of sediment spiked at 1.0 ng/g dry sediment. Recoveries ranged from 61.6 to 118% with relative standard deviations of 2.1–17% when spiked at 5.0 and 50 ng/g dry sediment. The three reference sediments, spiked with 50 ng/g dry weight of the pesticide mixture, were aged for 0.25, 1, 4, 7, and 14 days. Recoveries of the pesticides in the sediments generally decreased with increased aging time, but the magnitude of the decline was pesticide and sediment dependent. The developed method was applied to field-collected sediments from the Central Valley of California.
Comparison of Phosphate Materials for Immobilizing Cadmium in Soil by Chang Oh Hong; Doug Young Chung; Do Kyoung Lee; Pil Joo Kim (pp. 268-274).
A study was conducted to compare the effects of phosphate (P) materials in reducing cadmium extractability. Seven P materials (commercial P fertilizers—fused phosphate (FP), ‘fused and superphosphate’ [FSP], and rock phosphate [RP]; P chemicals—Ca[H2PO4]2·H2O, [NH4]2HPO4, KH2PO4, and K2HPO4) were selected for the test. The selected P source was mixed with Cd-contaminated soil at the rate of 0, 200, 400, 800, and 1,600 mg P kg−1 under controlled moisture conditions at 70% of water holding capacity, then incubated for 8 weeks. FP, Ca(H2PO4)2 ∙ H2O, KH2PO4, and K2HPO4 significantly decreased NH4OAc-extractable Cd (plant-available form) concentrations with increasing application rates. Compared to other phosphate materials used, K2HPO4 was found to be the most effective in reducing the plant-available Cd concentration in soil, mainly due to the negative charge increase caused by soil pH and phosphate adsorption. Contrary to the general information, FSP and (NH4)2HPO4 increased Cd extractability at low levels of P application (<400 mg kg−1), and thereafter Cd extractability decreased significantly with increasing application rate. RP scarcely had an effect on reducing Cd extractability. Ion activity products of CdHPO4, Cd(OH)2, and CdCO3 analyzed by the MINTEQ program were significantly increased by K2HPO4 addition, but the effect of Cd-P compound formation on reducing Cd extractability was negligible. Conclusively, the P-induced alleviation of Cd extractability can be attributed primarily to Cd immobilization due to the increase in soil pH and negative charge rather than Cd-P precipitation, and therefore, alkaline P materials such as K2HPO4 are effective for immobilizing soil Cd.
Mass Loadings of Triclosan and Triclocarbon from Four Wastewater Treatment Plants to Three Rivers and Landfill in Savannah, Georgia, USA by Kurunthachalam Senthil Kumar; S. Mahalakshmi Priya; Aaron M. Peck; Kenneth S. Sajwan (pp. 275-285).
Triclosan (TCS) and triclocarbon (TCC) are bactericides used in various consumer and personal-care products. Recent studies have revealed considerable levels of these bactericides in wastewater, aquatic wildlife, and human samples. Consequently, in this study we measured TCS and TCC in influent and effluent, sludge, and pond water/sediment samples from four wastewater treatment plants (WWTPs) and three major rivers in Savannah, Georgia (USA). Among these treatment plants, the Wilshire plant showed elevated concentrations of TCS (influent, 86,161; effluent, 5370 ng/L), whereas TCC was greater in the Georgetown plant (influent, 36,221) and the Wilshire plant effluent (3045 ng/L). Clearance of TCS and TCC were 95 and 92%, respectively, in the President Street plant, 94 and 85%, respectively, in the Wilshire plant, 99 and 80%, respectively, in the Travis Field plant, and 99 and 99%, respectively, in the Georgetown plant. Based on the mass flow estimate, 138 g/day of TCS and 214 g/day TCC are released into the Savannah River from the President Street, Travis Field, and Wilshire plants and 1.60 g/day TCS and 1.64 g/day TCC are released to the Ogeechee River from the Georgetown plant. Based on the sludge data, the loading estimate can be calculated that 32 and 0.004 g/day TCS and 53 and 0.01 g/day TCC (nonincinerated and incinerated, respectively) are deposited in landfill from the President Street plant alone, whereas 4.6, 26, and 6.8 g/day TCS and 3.8, 23, and 5.9 g/day TCC (wet sludge) were produced and dumped in landfill from the rest of the WWTPs. Incineration of wet sludge can eliminate 99.99% of TCS and TCC. Concentrations of TCS and TCC in water and sediment were greater in the Vernon River, followed by the Savannah River and the Ogeechee River.
Occurrence of Organic Wastewater and Other Contaminants in Cave Streams in Northeastern Oklahoma and Northwestern Arkansas by Joseph R. Bidwell; Carol Becker; Steve Hensley; Richard Stark; Michael T. Meyer (pp. 286-298).
The prevalence of organic wastewater compounds in surface waters of the United States has been reported in a number of recent studies. In karstic areas, surface contaminants might be transported to groundwater and, ultimately, cave ecosystems, where they might impact resident biota. In this study, polar organic chemical integrative samplers (POCISs) and semipermeable membrane devices (SPMDs) were deployed in six caves and two surface-water sites located within the Ozark Plateau of northeastern Oklahoma and northwestern Arkansas in order to detect potential chemical contaminants in these systems. All caves sampled were known to contain populations of the threatened Ozark cavefish (Amblyopsis rosae). The surface-water site in Oklahoma was downstream from the outfall of a municipal wastewater treatment plant and a previous study indicated a hydrologic link between this stream and one of the caves. A total of 83 chemicals were detected in the POCIS and SPMD extracts from the surface-water and cave sites. Of these, 55 chemicals were detected in the caves. Regardless of the sampler used, more compounds were detected in the Oklahoma surface-water site than in the Arkansas site or the caves. The organic wastewater chemicals with the greatest mass measured in the sampler extracts included sterols (cholesterol and β-sitosterol), plasticizers [diethylhexylphthalate and tris(2-butoxyethyl) phosphate], the herbicide bromacil, and the fragrance indole. Sampler extracts from most of the cave sites did not contain many wastewater contaminants, although extracts from samplers in the Oklahoma surface-water site and the cave hydrologically linked to it had similar levels of diethylhexyphthalate and common detections of carbamazapine, sulfamethoxazole, benzophenone, N-diethyl-3-methylbenzamide (DEET), and octophenol monoethoxylate. Further evaluation of this system is warranted due to potential ongoing transport of wastewater-associated chemicals into the cave. Halogenated organics found in caves and surface-water sites included brominated flame retardants, organochlorine pesticides (chlordane and nonachlor), and polychlorinated biphenyls. The placement of samplers in the caves (near the cave mouth compared to farther in the system) might have influenced the number of halogenated organics detected due to possible aerial transport of residues. Guano from cave-dwelling bats also might have been a source of some of these chlorinated organics. Seven-day survival and growth bioassays with fathead minnows (Pimephales promelas) exposed to samples of cave water indicated initial toxicity in water from two of the caves, but these effects were transient, with no toxicity observed in follow-up tests.
Spatial Distribution of Antimony and Arsenic Levels in Manadas Creek, an Urban Tributary of the Rio Grande in Laredo, Texas by Marcia Baeza; Jianhong Ren; Sushma Krishnamurthy; Thomas C. Vaughan (pp. 299-314).
The Rio Grande and its tributaries represent a critical water source for both the human population and the ecological resources of the Rio Grande drainage basin. Manadas Creek, an urban tributary of the Rio Grande, is located in an industrialized area of Laredo, Texas, where warehouses, a major railroad, and a decommissioned antimony (Sb) smelter are located. Previous studies have found that the creek water is contaminated with heavy metals such as Sb and arsenic (As). However, data on the metal distribution in this creek are very limited. Herein, water and sediment core samples were collected from six sites along the creek in February, April, and May 2008. Samples were analyzed for dissolved and total metals in water, total metals in sediments, and available (soluble-exchangeable, surface adsorbed, and organically bound) fractions of metals associated with the sediments. Results show that concentrations of Sb in the water and sediment samples were significantly lower at the upstream control site compared to the two sites located near the decommissioned smelter. Decreasing levels of Sb were found at the sites located downstream. The As levels in the sediment remained constant at different depths, whereas Sb varied significantly. A high level, 420 mg/kg, of sediment Sb was found at the maximum sediment depth of 35.0 cm sampled. In addition, 65.7–76.9% Sb and 80.3–85.6% As were in their residual form, 15.0–22.5% Sb and 6.2–11.4% As were bound to organic matter, and the remaining As and Sb were in the soluble and surface adsorbed fractions. Pearson correlation analyses indicated that the distribution of Sb was only moderately correlated to iron and nickel in the sediment and its correlation with the sediment properties measured was insignificant. Cluster analyses only grouped the two Sb isotopes together for the sediments collected in May, indicating that sources other than natural occurrence were associated with Sb. The high level of sediment Sb observed indicates that the sediment bed of Manadas Creek was acting as a holding reservoir for Sb and a potential source for the Sb level in the stream water. Thus, the loss of the sediment Sb and the Sb level in the water column must be closely related to the mobility of the bed sediments and the fate of the sediment-associated Sb.
Direct and Indirect Effects of the Fungicide Carbendazim in Tropical Freshwater Microcosms by Michiel A. Daam; Kriengkrai Satapornvanit; Paul J. Van den Brink; António J. A. Nogueira (pp. 315-324).
Direct and indirect effects of the fungicide carbendazim on ecosystem structure and functioning were studied ≤8 weeks after application (nominal concentrations: 0, 3.3, 33, 100, and 1000 μg/L) to outdoor microcosms in Thailand. Direct effects on macroinvertebrates are discussed in detail in a separate article. The present article presents the effects on other end points and discusses the hypothesized ecologic effect chain. Negative treatment effects on the zooplankton community were only recorded for the highest carbendazim treatment (NOECcommunity = 100 μg/L). The rotifer Keratella tropica, cladocerans (Moina micrura, Ceriodaphnia cornuta, and Diaphanosoma sp.), and cyclopoid copepods were decreased or even eliminated at this treatment level. The decrease in zooplankton and macroinvertebrate abundances was accompanied by an increase in numbers of several tolerant invertebrates, presumably caused by a release from competition and predation. The death of sensitive invertebrates probably also led to an overall decreased grazing pressure because increased levels of chlorophyll-a and bloom of the floating macrophyte Wolffia sp. were noted. The increase in primary producers is discussed to be the probable cause of changes in physicochemical water conditions, eventually resulting in an anoxic water layer during the last 3 weeks of the experiment. This is likely to have resulted in decreased invertebrate abundances noted in that period. Furthermore, the decreased decomposition of Musa (banana) leaves observed 8 weeks after application is considered to be the indirect effect of a decreased microbial activity resulting from these anoxic water conditions, rather than a direct toxic effect of carbendazim.
Lethal and Sublethal Effects of Embryonic and Larval Exposure of Hyla versicolor to Stormwater Pond Sediments by Adrianne B. Brand; Joel W. Snodgrass; Matthew T. Gallagher; Ryan E. Casey; Robin Van Meter (pp. 325-331).
Stormwater ponds are common features of modern stormwater management practices. Stormwater ponds often retain standing water for extended periods of time, develop vegetative characteristics similar to natural wetlands, and attract wildlife. However, because stormwater ponds are designed to capture pollutants, wildlife that utilize ponds might be exposed to pollutants and suffer toxicological effects. To investigate the toxicity of stormwater pond sediments to Hyla versicolor, an anuran commonly found using retention ponds for breeding, we exposed embryos and larvae to sediments in laboratory microcosms. Exposure to pond sediments reduced survival of embryos by ~50% but did not affect larval survival. Larvae exposed to stormwater pond sediment developed significantly faster ( $$ ar{x} = 39 $$ days compared to 42 days; p = 0.005) and were significantly larger at metamorphosis ( $$ ar{x} = , 0. 4 9 $$ g compared to 0.36 g; p < 0.001) than controls that were exposed to clean sand. Substantial amounts (712–2215 mg/l) of chloride leached from pond sediments into the water column of treatment microcosms; subsequently, survival of embryos was negatively correlated (r 2 = 0.50; p < 0.001) with water conductivity during development. Our results, along with the limited number of other toxicological studies of stormwater ponds, suggest that road salt contributes to the degradation of stormwater pond habitat quality for amphibian reproduction and that future research should focus on understanding interactions among road salts and other pollutants and stressors characteristic of urban environments.
Effects of the Veterinary Pharmaceutical Ivermectin on Soil Invertebrates in Laboratory Tests by J. Römbke; K. A. Krogh; T. Moser; A. Scheffczyk; M. Liebig (pp. 332-340).
As part of the risk assessment of veterinary pharmaceuticals, the potential impact of these chemicals on soil ecosystems has to be determined according to European law. However, almost no data from standardized laboratory tests are available. Therefore, in the EU FP6 ERAPharm, the effects of the widely used veterinary pharmaceutical ivermectin, an anthelminthic, were studied in chronic laboratory tests performed according to OECD (Organisation for Economic Co-operation and Development) and ISO (International Organization for Standardization) guidelines. In detail, three soil invertebrate species—the earthworm Eisenia fetida, the springtail Folsomia candida, and the predatory mite Hypoaspis aculeifer—were tested. The nominal concentrations of ivermectin mixed into the test substrate artificial soil was verified using residue analysis, which indicated that the test substance is persistent for at least up to 28 days. As expected when considering the mode of action of this substance, survival and reproduction of collembolans were clearly affected [LC50 = 8.4 mg/kg soil dry weight (dw); NOECrepro = 0.3 mg/kg soil (dw)]. Predatory mites reacted less sensitively [LC50 ≥ 31.6 mg/kg soil (dw); NOECrepro = 3.2 mg/kg soil (dw)]. Earthworm survival and reproduction were affected in the same order of magnitude as the predatory mites [LC50 ≥ 10 mg/kg soil (dw); NOECrepro = 2.5 mg/kg soil (dw)]. These results are in good agreement with the few data known from nonstandardized tests for the same or related soil invertebrate species. The results of these tests indicate that the effects of ivermectin on soil invertebrates—in particular, collembolans—cannot be excluded at field-relevant concentrations, as determined in a risk assessment according to VICH guidelines. More sophisticated higher-tier tests (e.g., in multispecies or semifield test systems) are recommended in order to assess the potential risk more accurately.
Assessment of Heavy Metal and Pesticide Levels in Soil and Plant Products from Agricultural Area of Belgrade, Serbia by Mirjana Marković; Svjetlana Cupać; Rada Đurović; Jelena Milinović; Petar Kljajić (pp. 341-351).
This study was aimed to assess the levels of selected heavy metals and pesticides in soil and plant products from an agricultural area of Belgrade, Serbia and to indicate possible sources and risks of contamination. Soil, vegetable, and fruit samples from the most important agricultural city areas were collected from July to November of 2006. Metal contents were determined by atomic absorption spectrometry, whereas pesticide residues were analyzed by gas chromatography–mass spectrometry after extraction performed using solid-phase microextraction technique. Soil characterization based on the determination of selected physical and chemical properties revealed heterogeneous soils belonging to different soil groups. The concentrations of lead, cadmium, copper, and zinc in soil samples do not exceed the limits established by national and international regulations. Residues of the herbicide atrazine were detected in three soil samples, with levels lower than the relevant limit. The presence of other herbicides, namely prometryn, chloridazon, acetochlor, flurochloridone, and napropamide, was registered in some soil samples as well. Among the insecticides investigated in the soil, fenitrothion and chlorpyrifos were the only ones detected. In most of the investigated vegetable samples from the Obrenovac area, Pb and Cd contents are higher in comparison with the maximum levels, indicating the emission of coal combustion products from local thermal power plants as a possible source of contamination. Residue levels of some herbicides and insecticides (metribuzin, trifluralin, pendimethalin, bifenthrin, chlorpyrifos, and cypermethrin) determined in tomato, pepper, potato, and onion samples from Slanci, Ovča, and Obrenovac areas are even several times higher than the maximum residue levels. Inappropriate use of these plant protection products is considered to be the most probable reason of contamination. Because increased levels of heavy metals and pesticide residues found in plant products could pose a risk to consumers’ health, their continual monitoring before product distribution to city markets is indispensable.
Pesticide Residues in Coastal Waters Affected by Rice Paddy Effluents Temporarily Stored in a Wastewater Reservoir in Southern Japan by Nathaniel C. Añasco; Jiro Koyama; Seiichi Uno (pp. 352-360).
This paper presents the occurrence, distribution, and environmental impact of pesticide residues in coastal water in southern Japan that receives effluents from a wastewater reservoir temporarily storing surface runoffs of rice paddy fields located near the coastline during the 2005 rice planting season. Concentrations of 14 target pesticides were measured by GC-MS and the hazards posed by the most important pesticides detected were evaluated by acute toxicity tests using a marine diatom, Chaetoceros sp., and a marine amphipod, Hyale barbicornis. Six pesticides (fenobucarb, flutolanil, iprobenfos, mefenacet, phthalide, pyriproxyfen) were detected in the coastal water, with three pesticides (fenobucarb, iprobenfos, and mefenacet) having 100% frequencies of detection. The maximum concentration of mefenacet, at 4.22 μg/L, was at least one magnitude higher than that of fenobucarb and iprobenfos, at 0.27 and 0.19 μg/L, respectively, while the three remaining pesticides had concentrations just around the detection limit of 0.01 μg/L. Consequently, detected concentrations of mefenacet were highly correlated with salinity levels, confirming that the wastewater reservoir is a major source of rice pesticide residues in this particular coastal environment. Hence, the spatial distribution of mefenacet was simulated using their relationship and the results indicate that mefenacet has a tendency to enter and spread to a relatively wide portion of the coastal area during the rice planting season. There is also a possibility that the other pesticides used in rice farming such as fenobucarb and iprobenfos may show similar distribution patterns in coastal waters when they are present in the wastewater reservoir at higher concentrations. These pesticides, however, manifested low acute toxicities to both Chaetoceros sp. and H. barbicornis, suggesting little impact to marine organisms.
Phosphate-Solubilizing and Plant-Growth-Promoting Pseudomonas aeruginosa PS1 Improves Greengram Performance in Quizalafop-p-ethyl and Clodinafop Amended Soil by Munees Ahemad; Mohammad Saghir Khan (pp. 361-372).
The quizalafop-p-ethyl- and clodinafop-tolerant phosphate-solubilizing and plant-growth-promoting Pseudomonas aeruginosa PS1 isolated from the rhizospheric soils of mustard was used to determine its phosphate-solubilizing activity and other plant-growth-promoting traits both in the presence and absence of technical grade quizalafop-p-ethyl and clodinafop under in vitro conditions. Quizalafop-p-ethyl (at 40, 80, and 120 ppb) and clodinafop (at 400, 800, and 1200 ppb) reduced the P-solubilizing activity, synthesis of indole-3-acetic acid, and siderophores progressively with increasing concentrations of each herbicide. Hydrogen cyanide and ammonia synthesisized by this strain, however, did not change. Furthermore, the effects of three concentrations each of quizalafop-p-ethyl [40 (recommended dose), 80, and 120 ppb] and clodinafop [400 (recommended dose), 800, and 1200 ppb] were evaluated on plant-growth-promoting Pseudomonas aeruginosa strain PS1 inoculated greengram plants, grown in sandy clay loam soil. Generally, all of the concentrations of both quizalafop-p-ethyl and clodinafop showed phytotoxicity and severely affected the growth, symbiosis, grain yield, and nutrient uptake by greengram plants. The toxicity of quizalafop-p-ethyl and clodinafop enhanced gradually with the increase in the dose rate of herbicides. Quizalafop-p-ethyl was more toxic than clodinafop. In contrast, herbicide-tolerant P. aeruginosa strain PS1 when used with herbicides increased the measured parameters at all concentrations. Both quizalafop-p-ethyl at 120 ppb and clodinafop at 400 ppb increased total chlorophyll content, leghemoglobin, root N, shoot N, root P, shoot P, seed yield, and seed protein, relative to the uninoculated control. The study suggests that the phytotoxicity of herbicides to legumes could be reduced by applying the growth-promoting herbicide-tolerant strain of Pseudomonas aeruginosa PS1.
Modelling the Long-Term Fate of Mercury in a Lowland Tidal River. I. Description of Two Finite Segment Models by M. Cristina B. Braga; Jason W. Birkett; John N. Lester; George Shaw (pp. 373-382).
Crucial determinants of the potential effects of mercury in aquatic ecosystems are the speciation, partitioning, and cycling of its various species. These processes are affected by site-specific factors, such as water chemistry, sediment transport, and hydrodynamics. This study presents two different approaches to the development of one-dimensional/dynamic-deterministic models for the evaluation and prediction of mercury contamination in a lowland tidal river, the River Yare (Norfolk, UK). The models described here were developed to encompass the entire river system and address the mass balance of mercury in a multicompartment system, including tidal reversal and saline limit. The models were focused on river systems, with the River Yare being used as a case study because previous modelling studies have been centred on lakes and wetlands whilst there is a paucity of information for rivers. Initial comparisons with actual measured water parameters (salinity and suspended solids) indicate that both models exhibit good agreement with the actual values.
Modelling the Long-Term Fate of Mercury in a Lowland Tidal River. II. Calibration and Comparison of Two Models with Field Data by M. Cristina B. Braga; Jason W. Birkett; George Shaw; John N. Lester (pp. 383-393).
This study presents results of the application of two-one-dimensional/dynamic-deterministic models developed to evaluate and predict mercury contamination of a lowland river, the River Yare, Norfolk, UK. As a general indication of model performance, MODEL 1 produced a prediction of the overall mass balance of mercury in the River Yare that was 6% lower than an estimate, based on measurements, and 10% lower than the prediction provided by MODEL 2. The mercury surficial sediment concentrations calculated by MODEL 1 varied from 0.46 mg kg−1 in 1995 (Reach 3) to 3.55 mg kg−1 in 1986 (Reaches 6 and 7), whereas the minimum mercury concentration calculated by MODEL 2 was 0.42 mg kg−1 in 1995 (Reach 3) and the maximum was 8.45 mg kg−1 in 1986 (Reach 5). Average mercury concentrations experimentally measured in surficial sediments ranged from 0.47 mg kg−1 in 1995 (Reach 3) to 8.10 mg kg−1 in 1986 (Reach 6). MODEL 2 gave an excellent prediction of mercury in fish flesh compared with the results obtained from the actual analysis of fish flesh. Both models demonstrated good ability to simulate actual values determined for all compartments, water, surficial sediments, bottom sediments, and fish.
Temporal Trend of Butyltins in Seawater, Sediments, and Mussels from Busan Harbor of Korea Between 2002 and 2007: Tracking the Effectiveness of Tributylin Regulation by Minkyu Choi; Hyo-Bang Moon; Jun Yu; Ji-Yeong Eom; Hee-Gu Choi (pp. 394-402).
Butyltins were determined in seawater, sediments, and mussels (Mytilus edulis) collected from Busan Harbor, the largest commercial harbor in Korea, to assess the contamination status and the effectiveness of tributylin (TBT) restriction. TBT concentrations were found to be 7.6 ± 8.3 ng Sn/L in seawater, 387 ± 606 ng Sn/g dry weight (wt) in sediments, and 322 ± 167 ng Sn/g dry wt in mussels, and are comparable to those in the largest harbors worldwide. TBT levels were highest at locations near shipyards and related facilities. Busan Harbor was characterized by the long-term history of butyltin contamination, based on the lowered TBT/DBT ratios in environmental matrices. The temporal trend of TBT levels decreased significantly in seawater and mussels from 2002 to 2007, probably as a consequence of the legislative action in Korea (MOE Regulation 154/2000). However, TBT in sediments did not show any trend, suggesting a long half-life for TBT, about 17 years, in sediments.
Polybrominated Diphenyl Ethers in Outmigrant Juvenile Chinook Salmon from the Lower Columbia River and Estuary and Puget Sound, Washington by Catherine A. Sloan; Bernadita F. Anulacion; Jennie L. Bolton; Daryle Boyd; O. Paul Olson; Sean Y. Sol; Gina M. Ylitalo; Lyndal L. Johnson (pp. 403-414).
Previous studies have examined the presence, distribution, and concentrations of toxic contaminants in two major waterways in the Pacific Northwest: the lower Columbia River and Estuary (LCR&E) and Puget Sound, Washington. However, those studies have not reported on the levels of polybrominated diphenyl ethers (PBDEs) in juvenile Chinook salmon (Onchorynchus tshawytscha). Populations of Chinook salmon from the LCR&E and Puget Sound are declining, and some stocks are currently listed as “threatened” under the Endangered Species Act. Bioaccumulation of contaminants, including PBDEs, by juvenile Chinook salmon in the LCR&E and Puget Sound is of concern due to the potential toxicity of the contaminants and associated sublethal effects in fish. In this article, we present the concentrations of PBDEs measured in gutted bodies and stomach contents of outmigrant juvenile Chinook salmon collected at six sites in the LCR&E and four sites in Puget Sound. For comparison, we also analyzed gutted bodies of juvenile Chinook salmon from eight hatcheries in the LCR&E as well as samples of the hatchery fish feeds. The mean ∑PBDE concentrations measured in bodies of juvenile Chinook salmon from the different sites ranged from 350 to 2800 ng/g lipid weight, whereas those in stomach contents ranged from less than the quantitation limit (<2 ng/g wet weight) to 39 ng/g wet weight. The levels of PBDEs in the hatchery fish were significantly lower than those measured in the salmon samples collected from the LCR&E and Puget Sound. These results show that outmigrant juvenile Chinook salmon in the LCR&E and Puget Sound have been exposed to PBDEs in the environment and that these chemicals are bioaccumulating in their tissues; thus, the potential effects of PBDEs on these salmon should be further investigated.
Risk Assessment of Residual DDTs in Freshwater and Marine Fish Cultivated Around the Pearl River Delta, China by S. Y. Leung; C. K. Kwok; X. P. Nie; K. C. Cheung; M. H. Wong (pp. 415-430).
Six species of freshwater fish collected from 10 fishponds in Shunde and Zhongshan, China, four species of marine fishes collected from different mariculture farms [four in Hong Kong (Tung Lung Chau, Ma Wan, Cheung Chau and Kat O) and two in mainland China (Daya Bay and Shenzhen)] together with feed (both trash fish and commercial pellets) and sediment were analyzed for DDTs. Total DDTs in freshwater fish flesh decreased in the order of: carnivores [1742 μg/kg lipid weight (l.w.)] > herbivores (165 μg/kg, l.w.) > omnivores (42.5 μg/kg, l.w.), with the highest concentration detected in mandarin fish (Siniperca chuatsi) (2641 μg/kg, l.w.). For marine fish, snubnose pompano (Trachinotus blochii) and orange-spotted grouper (Epinephelus coioides) collected in Ma Wan contained elevated levels of total DDTs (2590 and 2034 μg/kg l.w., respectively). Trash fish used in both freshwater and marine fish farms contained significantly higher levels (86.5–641 μg/kg l.w.) (p < 0.05) of DDTs than in commercial pellets, but correlations between DDT levels in fish feed and muscle were not significant. The elevated biota-sediment accumulating factor for tilapia (Tilapia mossambicus) (24.1) indicated that accumulation of DDTs from sediment to the fish was evident. It can be concluded that trash fish should not be used for fish culture in order to lower the level of residual DDTs in fish muscle.
Effects of Diet Composition and Trophic Structure on Mercury Bioaccumulation in Temperate Flatfishes by Eric J. Payne; David L. Taylor (pp. 431-443).
The summer flounder Paralichthys dentatus and winter flounder Pseudopleuronectes americanus support valuable fisheries along the northeastern United States. The importance of these flatfish as a human dietary resource indicates they are potential sources of mercury (Hg) to fish-consuming citizens. In this study, summer flounder (SF) and winter flounder (WF) were collected from the Narragansett Bay (Rhode Island, USA) and were measured for total Hg burden in whole-body or dorsal muscle tissue. Interspecies differences in Hg contamination were analyzed relative to flounder body size, age, and Hg content of preferred prey. Stable isotope signatures were also used to elucidate the effect of trophic processes on Hg accumulation in the estuarine food web. The mean Hg content of SF exceeded concentrations measured in WF across multiple life-history stages (0.039–0.100 and 0.016–0.029 mg Hg/kg wet weight for SF and WF, respectively), and observed values for both species were lower than the US Environmental Protection Agency regulatory threshold of 0.3 mg Hg/kg wet weight. Total Hg concentrations were also positively correlated with flounder age and length, verifying that both flatfish bioaccumulate Hg. SF accumulate Hg at an accelerated rate, however, owing to this species consuming Hg-enriched prey (teleosts, squid, and macrocrustaceans; mean Hg content = 0.023 mg Hg/kg wet weight), whereas WF feed on prey with low Hg levels (amphipods and polychaetes; mean Hg content = 0.013 mg Hg/kg wet weight). The positive correlation observed between mean biota Hg content and stable nitrogen (δ15N) isotope signatures further indicates that Hg is trophically transferred through the food web, and higher trophic level organisms (i.e., enriched δ15N) have increased Hg concentrations. Therefore, results from this study suggest that dietary preference and trophic structure are the main factors affecting Hg bioaccumulation in the estuary. Total Hg concentrations of flatfish from the Narragansett Bay, however, do not necessarily reflect coastwide contamination patterns. This reinforces the importance of having research conducted at sufficiently small spatial scales, including the local assessment of Hg contamination for the purpose of issuing state consumption advisories.
Mercury Levels in Muscle of Six Species of Turtles Eaten by People Along the Rio Negro of the Amazon Basin by Larissa Schneider; Lauren Belger; Joanna Burger; Richard C. Vogt; Camila R. Ferrara (pp. 444-450).
Mercury levels in the Amazon River are generally high, but there are no published studies on Hg levels in turtles from the region. In this study, levels of Hg were examined in the muscle of six species of turtles in the Rio Negro in the Amazon basin of Brazil, including Podocnemis unifilis, Podocnemis expansa, Podocnemis erythrocephala, Podocnemis sextuberculata, Peltocephalus dumerilianus, and Chelus fimbriatus. It is important to analyze Hg levels in chelonians in this region because of the potential health risk to humans and other receptors that eat them, as well as their potential use as bioindicators. The effect of sex, weight, and carapace length on Hg concentrations in turtle muscle was examined to determine if the levels represent a health risk to riverine people. There was a significant interspecific difference in Hg levels but no differences as a function of size or gender. The highest Hg level was found in Chelus fimbriatus (mean = 432 ppb, standard deviation ± 196 ppb), followed by Peltocephalus dumerilianus (106 ± 41 ppb), Podocnemis expansa (62 ± 49 ppb), P. sextuberculata (61 ± 40 ppb), P. unilifis (35 ± 17 ppb), and P. erythrocephala (33.1 ± 17 ppb). Of the species studied, the piscivorous C. fimbriatus had the highest Hg level. Hg levels in turtles were similar to the levels found in fish from the same basin. Levels of Hg in the muscle of C. fimbriatus are sufficiently high to pose a potential risk to humans who consume them. This study represents the first comparative study of Hg levels in muscle of six species of turtles.
Anticoagulant Rodenticides in Three Owl Species from Western Canada, 1988–2003 by Courtney A. Albert; Laurie K. Wilson; Pierre Mineau; Suzanne Trudeau; John E. Elliott (pp. 451-459).
Anticoagulant rodenticides are widely used to control rodent infestations. Previous studies have shown that nontarget organisms, such as birds, are at risk for both primary and secondary poisoning. This paper presents rodenticide residue information on the livers from 164 strigiformes which included barn owls (Tyto alba), barred owls (Strix varia), and great horned owls (Bubo virginianus), collected from 1988 to 2003 in the province of British Columbia and the Yukon Territory, Canada. Livers were analyzed for brodifacoum, bromadiolone, chlorophacinone, diphacinone, difethialone, and warfarin. Our results show that, of the 164 owl livers analyzed, 70% had residues of at least one rodenticide, and of these 41% had more than one rodenticide detected. Of the three species of owls examined, barred owls were most frequently exposed (92%, n = 23); brodifacoum and bromadiolone were most often detected, with liver concentrations ranging from 0.001 to 0.927 mg/kg brodifacoum, and 0.002 to 1.012 mg/kg bromadiolone. Six of the owls (three barred owls, two barn owls, and one great horned owl) were diagnosed as having died from anticoagulant poisoning; all six owls had brodifacoum residues in the liver.
Levels of Cadmium, Mercury, and Lead in Magellanic Penguins (Spheniscus magellanicus) Stranded on the Brazilian Coast by Claudia M. Vega; Salvatore Siciliano; Paulo R. G. Barrocas; Sandra S. Hacon; Reinaldo C. Campos; Silvana do Couto Jacob; Paulo Henrique Ott (pp. 460-468).
Cadmium (Cd), mercury (Hg), and lead (Pb) were determined in samples of liver and breast muscles of first-year Magellanic penguins (Spheniscus magellanicus), from two different areas on the Brazilian coast, 35 on the Rio de Janeiro coast and 12 on the Rio Grande do Sul coast. In both areas, Cd concentrations in muscle samples were <0.025 μg/g. However, the Cd and Hg concentrations found in liver and Hg concentrations found in muscle showed a significant difference between the two regions. The geometric mean of the concentrations was higher in the specimens from Rio de Janeiro (Cd—6.8 μg/g; Hg—liver, 1.6 μg/g, and muscle, 0.4 μg/g wet weight) than in those from Rio Grande do Sul (Cd—2.3 μg/g; Hg—liver, 0.9 μg/g, and muscle, 0.1 μg/g wet weight). The site differences could be related to differences in diet influenced by geographic factors. Brazil’s southeastern coast is highly urbanized, and its coastal waters are contaminated by the waste of agricultural and industrial activities. There is a lack of information on the levels of heavy metals in S. magellanicus, however, their wide distribution and top position in the trophic chain make the use of stranded specimens an attractive source of information for monitoring heavy metals in the South Atlantic coast.
Influence of Parasitism on Trace Element Contents in Tissues of Red Fox (Vulpes vulpes) and Its Parasites Mesocestoides spp. (Cestoda) and Toxascaris leonina (Nematoda) by Ivana Jankovská; Daniela Miholová; Vladimír Bejček; Jaroslav Vadlejch; Miloslav Šulc; Jiřina Száková; Iva Langrová (pp. 469-477).
Bioaccumulation of cadmium, chromium, copper, manganese, nickel, lead, and zinc in 56 foxes (Vulpes vulpes) and their parasites Mesocestoides spp. (Cestoda) and Toxascaris leonina (Nematoda) was studied. The levels of heavy metals were determined in the livers and kidneys of the animals depending on parasitism in the following ranges: Pb, 0.029–3.556; Cd, 0.055–9.967; Cr, 0.001–0.304; Cu, 4.15–41.15; Mn, 1.81–19.94; Ni: 0.037–0.831; Zn, 52.0–212.9 μg/g dry weight (dw). Cd in parasites (0.038–3.678 μg/g dw) were comparable with those in the livers of the host and lower than in the kidneys (0.095–6.032 μg/g dw). Contents of Pb, Cr, Cu, Mn, Ni, and Zn in cestodes were predominantly higher than those in the kidney and liver of the host. Median lead levels in Mesocestoides spp. (45.6 μg/g dw) were 52-fold higher than in the kidney and liver of the red fox (Vulpes vulpes) infected by both parasites and median Pb values in T. leonina (8.98 μg/g dw) were 8-fold higher than in the tissues of the parasitized red fox. Bioaccumulation factors of copper, zinc, nickel, and manganese are lower than those of lead and mostly range from 1.9 to 24 for Mesocestoides spp. and from 1.5 to 6 for nematode T. leonina depending on the tissue of host and element. A significant decrease in the content of Pb was found in the kidney of animals infected by T. leonina (0.260 μg/g dw) as well as those infected by Mesocestoides spp. (0.457 μg/g dw) in comparison with the lead content (0.878 μg/g dw) in the kidneys of the nonparasitized red fox. Regardless of a bioaccumulation of copper and manganese in the parasites, a significant increase of the concentrations of Mn and Cu was observed in the host’s livers infected predominantly by Mesocestoides spp.
Tissue Distribution of Polychlorinated Biphenyls and Organochlorine Pesticides and Potential Toxicity to Alaskan Northern Fur Seals Assessed Using PCBs Congener Specific Mode of Action Schemes by Dongli Wang; Weilin L. Shelver; Shannon Atkinson; Jo-Ann Mellish; Qing X. Li (pp. 478-488).
The fur seal (Callorhinus ursinus) population has decreased in their primary breeding grounds in the Bering Sea; contamination is among suspected causes. Our goal was to better understand the extent of contamination of seal tissues with certain organochlorine compounds by measuring the concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in fur seal tissues from St. Paul Island, to gain a better perspective of tissue congener distribution and to evaluate the observed PCB levels against toxicologically significant levels for modes of action. Concentrations of 145 PCB congeners (∑145PCBs) and 12 OCPs were measured with gas chromatography–ion trap mass spectrometry in 8 different tissues of 10 male northern fur seals. The mean concentrations of ∑OCPs [in ng/g lipid weight (lw)] were 1180 in blubber, 985 in the heart, 1007 in the liver, 817 in the kidney, 941 in muscle, 660 in reproductive tissues, 204 in the brain, and 322 in the lung. The mean concentrations of ∑145PCBs (in ng/g lw) were 823 in blubber, 777 in the liver, 732 in the heart, 646 in reproductive tissues, 638 in muscle, 587 in the kidney, 128 in the lung, and 74.3 in brain tissues. Concentrations of PCBs affecting the aryl hydrocarbon receptor expressed as total PCB toxic equivalents (∑PCB-TEQs) ranged from 0.3 to 545 pg/g lw for the various tissues. The major contributors to ∑PCB-TEQs are CB-118 in muscle, brain, lung, kidney, and liver, CB-126 in blubber, and CB-118 and CB-126 equally in the heart and reproductive tissues. Concentrations of PCBs affecting Ca2+ homeostatsis expressed as the neurotoxic equivalent (NEQ) showed ∑PCB-NEQs ranged from 17.7 to 215 ng/g lw in all tissues. Although no composite measure of perturbation of thyroid function is available, sufficient amounts of congeners with high binding to the thyroxine transport system were present to warrant consideration of this mode of action in future studies. Analyses of 145 PCBs and mode of action evaluation suggest that PCB contamination could potentially exert an effect on the Alaskan northern fur seal population although the PCB concentrations have been decreasing in the fur seals over the last decade.