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Archives of Environmental Contamination and Toxicology (v.47, #1)
Arsenic Sorption by Carbonate-Rich Aquifer Material, a Control on Arsenic Mobility at Zimapán, México by F. M. Romero; M. A. Armienta; A. Carrillo-Chavez (pp. 1-13).
Arsenic retention by carbonate-rich aquifer material at Zimapán, México, was studied to gain insight into the processes controlling arsenic mobility in natural systems. Batch experiments showed that retention of soluble As (V) on carbonate-rich aquifer material was 35.3–90% in the pH range of 7–9 found in Zimapán natural water. Chemical and mineralogical compositions, point of zero charge (PZC), and experimental arsenic retention at various pH of three composite samples of limestone (M1, M2, M3) showed that sorption (adsorption and coprecipitation) may be one of the main processes controlling arsenic mobility in the Zimapán As-polluted aquifer. The PZC values approximately corresponded to the PZC reported for the main minerals present in each sample: hydrous ferric oxides (M1), calcite (M2), and the range from hydrous ferric oxides and calcite (M3). The chemical and mineralogical compositions of each sample explain the obtained PZC values. Experimental and modeled arsenic retention at various pH values on sample M1 corresponded to reported arsenic adsorption onto hydrous ferric oxides. Coprecipitacion of complex Ca arsenates or arsenic adsorption onto calcite or clay minerals could be the main processes of arsenic retention on samples M2 and M3. Groundwater flow through the granular, carbonate-rich, shallow aquifer may decrease the water As content as a result of these interactions. A remediation method based on the promotion of polluted water flow into the shallow aquifer could be developed from these results.
Assessment of the Pollution Status of Alluvial Plains: A Case Study for the Dredged Sediment-Derived Soils Along the Leie River by Bart Vandecasteele; Paul Quataert; Bruno De Vos; Filip M. G. Tack (pp. 14-22).
The concept of an integrated multifunctional river management is gaining importance. For major rivers, restoring the contact between rivers and alluvial plains is an important goal, as riparian areas have a specific role for several riverine processes. However, former and current human activities are an obstruction or a limitation for river restoration. We studied the influence of former dredging activities along the river Leie on the alluvial plain quality. A soil survey and an archive query for reconstructing the history of dredging operations were conducted simultaneously. The geographical impact expressed as topographical changes and covering of the original soil profile and related processes and biota was large. The pollution status of dredged sediment-derived soils was found to be far from negligible: concentrations of Cd, Cr, and Zn were, in 10% of the cases, higher than 20, 480, and 2800 mg kg−1 DM, respectively. Both agriculture and nature rehabilitation on dredged sediment-derived soils can only be accepted after profound risk assessment, and management should focus on ecological risk reduction. Results indicate the importance of soil quality assessment in alluvial plains for an integrated river management, rather than a priori assuming pristine soil conditions. The collected “off-line” sediment data can be used as a reconstruction of past sediment pollution, especially when long-term sediment monitoring programs are not available.
Assessment of Heavy Metal Contamination in Roadside Surface Soil and Vegetation from the West Bank by K. M. Swaileh; R. M. Hussein; S. Abu-Elhaj (pp. 23-30).
Concentrations of heavy metals (Pb, Cd, Cu, Zn, Fe, Mn, Ni, and Cr) were investigated in roadside surface soil and the common perennial herb inula (Inula viscosa L., Compositae). Samples were collected at different distances (0–200 m) perpendicular to a main road that connects two main cities in the West Bank. Average concentrations of metals in soil samples were: Pb, 87.4; Cd, 0.27; Cu, 60.4; Zn, 82.2; Fe, 15,700; Mn, 224; Ni, 18.9; and Cr, 42.4 μg · g−1. In plant leaves, concentrations were: Pb, 7.25; Cd, 0.10; Cu, 10.6; Zn, 47.6; Fe, 730; Mn, 140; Ni, 4.87; and Cr, 7.03 μg · g−1. Roadside contamination was obvious by the significant negative correlations between concentrations of metals in soil and plant samples and distance from road edge. Only cadmium concentrations in soil and plant samples were not associated with roadside pollution. Roadside contamination in plants and soil did not extend much beyond a 20 m distance from road. I. viscosa reflected roadside contamination better than soil and their metal concentrations showed much less fluctuations than those in soil samples. Washing plant leaves decreased Pb and Fe concentrations significantly, indicating a significant aerial deposition of both. I. viscosa can be considered as a good biomonitor for roadside metal pollution.
Effects of Pig Slurry on the Sorption of Sulfonamide Antibiotics in Soil by S. Thiele-Bruhn; M.-O. Aust (pp. 31-39).
Sorption of p-aminobenzoic acid (pABA) and five sulfonamide antibiotics to loess Chernozem topsoil amended with varied additions of pig slurry was investigated in batch trials. In unfertilized soil, partition coefficients (Kd) of sulfonamides ranged from 0.3 to 2.0. Strong sorption nonlinearity (1/n = 0.5 to 0.8) was best fitted by the Freundlich isotherm (R2 = 0.7 to 1.0) and was indicative for specific sorption mechanisms. Adsorption to pig slurry was much stronger, and nondesorbable portions were increased compared with soil. However, in a mixture of soil and slurry (50:1 w/w), sorption of the antibiotics was significantly decreased at a lower concentration range of pABA and the sulfonamides. This was attributed to competitive adsorption of dissolved organic matter (DOM) constituents from manure. An increase in pig slurry amendment resulted in increased total organic matter, DOM concentration, and ionic strength, but pH decreased. As a result, the nonadsorbed portions of pABA, sulfanilamide, and sulfadiazine (logDow < −0.4) ranged from 47% to 82% of the applied concentration in the differently manured substrates. Dissolved fractions of the antibiotics reached a maximum at a soil–slurry ratio of 9:1 and decreased with further addition of manure. This decrease was related to the formation of less-effective DOM associates in solution. The adsorbed and desorbed portions of the less-polar substances—sulfadimidine, sulfadimethoxine, and sulfapyridine (logDow > 0.1)—remained nearly constant in the presence of increased manure input. The pH changes caused by manure amendment strongly affected ionisation status of the latter compounds, thus resulting in increased adsorption, which compensated the mobilizing effect of DOM. It is suggested that the effect of manure be considered in test methods to determine the soil retention of pharmaceutical substances.
Development of a Sublethal Test to Determine the Effects of Copper and Lead on Scleractinian Coral Larvae by A. J. Reichelt-Brushett; P. L. Harrison (pp. 40-55).
A new sublethal toxicity test was developed in this study to measure the effect of copper and lead on the motility of coral larvae. Larval motility was significantly affected by copper and lead doses immediately after dosing. The copper EC50 values for motility of Goniastrea aspera brain coral larvae (12 h, 21 μg/L; 24 h, 16 μg/L; 48 h, 22 μg/L) were much lower than the copper LC50 values for G. aspera larval survival (6 h, 260 μg/L, and 24 h, 121 μg/L, for 5-day-old larvae and 6 h, 248 μg/L, and 24 h, 136.64 μg/L, for 6-day-old larvae) during the early part of the experiments. However, at later times, the LC50 values (48 h, 40 μg/L, for 5-day-old larvae and 48- h, 87 μg/L, for 6-day-old larvae) were similar to the EC50 values for larval motility. The lead 72-h EC50 value for G. aspera larval motility (2900 μg/L) was much lower than the lead 72-h LC50 value for larval survival (9890 μg/L). The results show that larval motility can be a useful parameter to measure in order to determine the sublethal effects of trace metals on coral larvae.
Response of Zooplankton and Phytoplankton Communities to Creosote-Impregnated Douglas Fir Pilings in Freshwater Microcosms by P. K. Sibley; M. L. Harris; K. T. Bestari; T. A. Steele; R. D. Robinson; R. W. Gensemer; K. E. Day; K. R. Solomon (pp. 56-66).
Creosote has been used extensively as an industrial wood preservative for the protection of marine pilings, railway ties, and utility poles and is a common source of polycyclic aromatic hydrocarbons (PAHs) into aquatic environments. At present, there is little information by which to judge the potential for creosote leached from impregnated pilings to cause toxicity to biota in aquatic environments. The objective of the current study was to assess the effects of creosote on zooplankton and phytoplankton populations in freshwater microcosms in relation to changes in the concentration and composition of PAHs leached from creosote-impregnated Douglas fir pilings during an 83-day exposure period. The study consisted of single microcosms containing one half, one, two, three, four, and six treated pilings. Two microcosms that received untreated pilings were used as controls. The total surface area of pilings in each microcosm was normalized by adding the appropriate number of untreated pilings. Samples were collected periodically between −14 and 83 days pre- and post-exposure to determine aqueous concentrations of 15 priority PAHs and to assess the response of zooplankton and phytoplankton communities. Plankton community response to creosote was analyzed using principle responses curves. Peak aqueous concentrations of ΣPAH occurred at day 7, ranging from 7.3 to 97.3 μg/L. Zooplankton abundance decreased in all microcosms after introduction of the impregnated pilings, with the magnitude of response varying as a function of aqueous creosote concentration. Using inverse regression, a no-observed-effect concentration for the zooplankton community of 11.1 μg/L was estimated. In contrast, algal abundance and diversity increased in all treatments between 7 and 21 days and attained levels up to twice that in control microcosms. This trend most likely reflected decreased grazing pressure because of the decrease in zooplankton populations, but it may also have reflected growth stimulation resulting from exposure to various constituents within the creosote mixture. Our results indicate that creosote leached from impregnated pilings deployed under typical conditions (e.g., wharves) may cause transient toxicity to benthic or limnetic communities shortly after deployment, but this likely poses few long-term risks to aquatic freshwater plankton communities.
Assessing the Risks to Zooplankton Grazers of Continuous Versus Pulsed Cypermethrin Exposures from Marine Cage Aquaculture by M. Medina; C. Barata; T. Telfer; D. J. Baird (pp. 67-73).
Survival responses of adult stages of the calanoid copepod A. tonsa during and after pulse exposures to cypermethrin were used to evaluate the environmental risks of cypermethrin treatments in the marine environment. To control sea lice, whole cages of salmon are exposed to cypermethrin over 1 h, after which the effluent is released into the environment and subsequently dissipates. Here we simulate this short presence of the chemical in the water column. The present study revealed that delayed toxicity in A. tonsa adults, here expressed as decreased survival, occurred following short term pulse exposures to cypermethrin. Persistent, sensitive responses to cypermethrin during and after pulse exposures of 24 h were similar to those reported in conventional acute tests, suggesting that damage caused by accumulated levels of cypermethrin during the first 24 h of exposure could explain long-term toxicity responses in A. tonsa. Delayed toxicity following 1 h pulse exposures to cypermethrin impaired male survival and therefore changed copepod sex ratios. The proposed delayed toxicity tests were considered sensitive and suggest potentially detrimental effects of cypermethrin on copepod populations within the vicinity of the cages. By monitoring toxic responses following pulsed exposures, delayed toxicity tests are especially suitable to assess environmental risks of poorly water-soluble substances that dissipate rapidly within the water column.
Determination of Laboratory and Field Elimination Rates of Polychlorinated Biphenyls (PCBs) in the Freshwater Mussel, Elliptio complanata by Sarah O’Rourke; Ken G. Drouillard; G. Douglas Haffner (pp. 74-83).
Chemical elimination rate constants (k2) were determined for 41 polychlorinated biphenyl (PCB) congeners in dosed freshwater mussels, Elliptio complanta, following a 150-day laboratory depuration period. Congener-specific elimination rates were inversely dependent on the n-octanol/water partition coefficient (KOW) of the chemical according to the regression equation: logk2 = (−0.59 ± 0.05) logKOW + (2.05 ± 0.28) (R2 = 0.80, p < 0.001). PCB elimination rate constants in E. complanta were lower than reported for zebra mussels and green-lipped mussels but similar in magnitude and KOW dependence to data reported for American oysters. In order to validate the laboratory-derived PCB elimination rate constants, mussels dosed with [13C]PCB153 were allowed to depurate at one of the biomonitoring stations utilized in the Detroit River Biomonitoring Program and sampled at the same time intervals as laboratory animals. The field elimination rate constant for [13C]PCB153 was significantly greater than, but within a factor of 3 of, the laboratory elimination rate constant determined for unlabeled PCB153. This similarity in estimates of k2 for labeled and unlabeled PCB153 indicates that there is relatively little error introduced by using laboratory PCB elimination rate constants to estimate PCB153 toxicokinetics in mussels deployed at this field station. Elimination rate constants determined for PCBs in this species were lower and exhibited a stronger KOW dependence than elimination rate constants reported for selected PAHs. This suggests that E. complanata may possess some capability for PAH biotransformation.
Polychlorinated Naphthalenes and Polychlorinated Biphenyls in Benthic Organisms of a Great Lakes Food Chain by N. Hanari; K. Kannan; Y. Horii; S. Taniyasu; N. Yamashita; D. J. Jude; M. B. Berg (pp. 84-93).
Invasion of zebra mussels, Dreissena polymorpha, and round gobies, Neogobius melanostomus, into the Great Lakes has altered the food web structure and thereby the pathways of toxic contaminants such as polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs). In this study, concentrations of PCNs and PCBs were measured in organisms of a Great Lakes benthic food chain encompassing zebra mussels. PCNs were found in all of the benthic organisms, including phytoplankton, algae, amphipods, zebra mussels, round goby, and smallmouth bass, Micropterus dolomieui. Concentrations of PCNs were greater in samples collected from the Raisin River than in samples from the St. Clair River. Biomagnification factors (BMF) for tetra- through octa-CN congeners in going from algae to zebra mussels from the St. Clair River ranged from 3 to 10. No major biomagnification of PCNs was found in round gobies, when concentrations were related to those in their prey species, zebra mussels. The biomagnification potential of PCNs appears to be similar to that of PCBs in the benthic food chain investigated in this study, despite the fact that PCNs may be metabolized by organisms higher in the food chain. Among several congeners, the BMFs of PCN congeners 35, 42, 43/45, 52/60, 58, and 66/67 were highest in round gobies. PCNs accounted for 1–22% of the total TEQs (toxic equivalents) of PCBs and PCNs in benthic organisms analyzed in this study. PCB congener 126 was the major contributor to TEQs, accounting for 72–99% of the PCB-TEQs in the food chain organisms analyzed.
Temporal Trends of Organochlorine Pesticides in Prawn (Macrobrachium nipponense) from Lake Kasumigaura, Japan, During 1978–2000 by Sunardi; K. Senthil Kumar; S. Masunaga; N. Iseki; S. Kasuga; J. Nakanishi (pp. 94-100).
Temporal trends of organochlorine pesticides such as β-hexachlorocyclohexane (β-HCH), hexachlorobenzene (HCB), and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p′-DDE), were determined in freshwater prawn (Macrobrachium nipponense) collected from Lake Kasumigaura in 1978 to 2000. The organochlorine pesticides elucidated a 72.4% decrease in β-HCH, from 42 (1978) to 11.6 ng/g fat (2000); an 89.6% decrease in HCB, from 1.64 (1978) to 0.17 ng/g fat (2000); and an 87.3% decrease in p,p′-DDE, from 97.5 (1978) to 12.4 ng/g fat (1992). After organochlorine pesticide prohibition in 1971, the declining trend of β-HCH, HCB, and p,p′-DDE concentrations persisting in the prawns could be approximated by exponential equations.
Effects of Chlorinated Solvents on Four Species of North American Amphibians by T. V. McDaniel; P. A. Martin; N. Ross; S. Brown; S. Lesage; B. D. Pauli (pp. 101-109).
Tetrachloroethylene (PCE), a dry cleaning and degreasing solvent, can enter groundwater through accidental leaks or spills, and concentrations as high as 75 mg/L have been reported in Canadian aquifers. Amphibians in wetlands receiving contaminated groundwater may be exposed to PCE and its degradation products, but little information is available on the impacts of these compounds on indigenous amphibian species. Acute (96-h static renewal) exposures to PCE and its major degradation products, trichloroethylene (TCE) and cis- and trans-dichloroethylene, were conducted on embryos of four North American amphibian species: wood frogs (Rana sylvatica), green frogs (R. clamitans), American toads (Bufo americanus), and spotted salamanders (Ambystoma maculatum). Subsequently, chronic exposures to PCE and TCE were conducted with the larvae of American toads. Both PCE and TCE were teratogenic to amphibian embryos; median effective concentrations (EC50s) for developmental deformities produced by PCE and TCE exposure for wood frogs and green frogs were 12 and 40 mg/L, respectively. Embryonic survivorship, however, was not compromised at these concentrations. American toads were less sensitive; the EC50 for developmental abnormalities was not attained at the highest test concentrations, 45 and 85 mg/L PCE and TCE, respectively. These results are pertinent in assessing the impact of groundwater pollution on an aquifer-fed wetland.
Copper/Metal Ratios in the Gills of Rainbow Trout (Oncorhynchus mykiss) Provide Evidence of Copper Exposure Under Conditions of Mixed-Metal Exposure by R. W. Daglish; B. F. Nowak; T. W. Lewis (pp. 110-116).
Previous work has suggested that the ratio of copper residues to zinc in the gills of rainbow trout may indicate short-term exposure to increased levels of waterborne copper. However, the effect of exposure to a combination of increased copper and zinc concentrates in the water column was unknown. We exposed rainbow trout to 8 ± 2 μg L−1, 40 ± 2 μg L−1 and 90 ± 9 μg L−1 of waterborne copper and 21 ± 3 μg L−1, 129 ± 40 μg L−1, and 202 ± 40 μg L−1 of waterborne zinc in a 2-factor experiments and gill copper and zinc residues were examined. Other gill parameters analyzed included the concentrations of calcium, magnesium, sodium, and potassium, liver copper and zinc concentrations and plasma copper, calcium, sodium, and potassium are also reported here. Copper residues in the gill filaments were significantly higher in the highest level of copper exposure (high Cu, 4.06 μg g−1; low Cu 2.41 μg g−1; 0 Cu 2.01 μg g−1; P = 0.001), whereas no differences were seen in zinc concentrations at any treatment level. Gill sodium and plasma calcium concentrations were also decreased at the highest waterborne copper concentrations. Although copper–zinc ratios in the gills were significantly different between the highest and lowest copper treatments (P = 0.002, F = 6.59), copper–sodium and copper–magnesium ratios were more sensitive to waterborne copper exposure (P = 0.001, F = 17.91 and P = 0.002, F = 15.45, respectively). These copper–metal ratios may be better indicators of copper loading in the water column.
Trace Metals in Tissues of Resident and Migratory Birds from a Lagoon Associated with an Agricultural Drainage Basin (SE Gulf of California) by Jorge Ruelas-Inzunza; Federico Páez-Osuna (pp. 117-125).
With the aim of knowing Cd, Cu, Fe, Mn, Pb, and Zn concentrations in selected tissues of birds from two places at Altata-Ensenada del Pabellón lagoon in the SE Gulf of California, 39 specimens of 14 species were analyzed. Migratory birds in this study showed the highest values of Cd, Cu, and Pb in liver; Fe and Mn, in viscera; and Zn, in feathers. Concerning the resident avifauna, the highest levels of Cd, Cu, and Fe were detected in the liver, Mn in viscera; and Pb and Zn, in feathers. Regarding Cu and Fe, higher concentrations were detected in migratory avifauna, while Mn and Zn were more accumulated in resident waterfowl. In the case of Cd and Pb, both elements showed a tendency to be more accumulated in resident seabirds. Statistical comparisons showed that in carnivorous and omnivorous birds the resident component was the group with higher levels in more comparisons where mainly Cu and Fe were involved. In the rest of the metals the differences in the concentrations in the distinct tissues of migratory versus resident species were not clearly evident in one group in particular. In a few cases, carnivorous birds had higher levels of Cd than herbivorous and omnivorous birds; for the rest of the metals there was not a clear trend of metal accumulation.
Contaminant Exposure and Reproductive Success of Ospreys (Pandion haliaetus) Nesting in Chesapeake Bay Regions of Concern by B. A. Rattner; P. C. McGowan; N. H. Golden; J. S. Hatfield; P. C. Toschik; R. F. Lukei Jr; R. C. Hale; I. Schmitz-Afonso; C. P. Rice (pp. 126-140).
Abstract:The Chesapeake Bay osprey population has more than doubled in size since restrictions were placed on the production and use of DDT and other toxic organochlorine contaminants in the 1970s. Ospreys are now nesting in the most highly polluted portions of the Bay. In 2000 and 2001, contaminant exposure and reproduction were monitored in ospreys nesting in regions of concern, including Baltimore Harbor and the Patapsco River, the Anacostia and middle Potomac rivers, and the Elizabeth River, and a presumed reference site consisting of the South, West, and Rhode rivers. A “sample egg” from each study nest was collected for contaminant analysis, and the fate of eggs remaining in each nest (n = 14–16/site) was monitored at 7- to 10-day intervals from egg incubation through fledging of young. Ospreys fledged young in regions of concern (observed success: 0.88–1.53 fledglings/active nest), although productivity was marginal for sustaining local populations in Baltimore Harbor and the Patapsco River and in the Anacostia and middle Potomac rivers. Concentrations of p,p′-DDE and many other organochlorine pesticides or metabolites, total PCBs, some arylhydrocarbon receptor-active PCB congeners and polybrominated diphenyl ether congeners, and perfluorooctanesulfonate were often greater in sample eggs from regions of concern compared to the reference site. Nonetheless, logistic regression analyses did not provide evidence linking marginal productivity to p,p′-DDE, total PCBs, or arylhydrocarbon receptor-active PCB congener exposure in regions of concern. In view of the moderate concentrations of total PCBs in eggs from the reference site, concerns related to new and emerging toxicants, and the absence of ecotoxicological data for terrestrial vertebrates in many Bay tributaries, a more thorough spatial evaluation of contaminant exposure in ospreys throughout the Chesapeake may be warranted.