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Archives of Environmental Contamination and Toxicology (v.36, #3)
Analysis of Organophosphate Hydraulic Fluids in U.S. Air Force Base Soils by M. D. David; J. N. Seiber (pp. 235-241).
Tri-aryl and tri-alkyl organophosphates (TAPs) have been used extensively as flame-retardant hydraulic fluids and fluid additives in commercial and military aircraft. Up to 80% of the consumption of these fluids has been estimated to be lost to unrecovered leakage. Tri-aryl phosphate components of these fluids are resistant to volatilization and solubilization in water, thus, their primary environmental fate pathway is sorption to soils. Environmental audits of military air bases generally do not include quantification of these compounds in soils. We have determined the presence and extent of TAP contamination in soil samples from several U.S. Air Force bases. Soils were collected, extracted, and analyzed using GC/FPD and GC/MS. Tricresyl phosphate was the most frequently found TAP in soil, ranging from 0.02 to 130 ppm. Other TAPs in soils included triphenyl phosphate and isopropylated triphenyl phosphate. Observations are made regarding the distribution, typical concentrations, persistence, and need for further testing of TAPs in soils at military installations. Additionally, GC and mass spectral data for these TAPs are presented, along with methods for their extraction, sample clean-up, and quantification.
Improved Method for the Storage of Groundwater Samples Containing Volatile Organic Analytes by D. A. Kovacs; D. H. Kampbell (pp. 242-247).
The sorption of volatile organic analytes from water samples by the Teflon septum surface used with standard glass 40-ml sample collection vials was investigated. Analytes tested included alkanes, isoalkanes, olefins, cycloalkanes, a cycloalkene, monoaromatics, a polynuclear aromatic, and two chloroethenes. Both laboratory prepared test mix solutions and petroleum contaminated groundwater from three field sites were tested. A rapid loss of n-alkane and isoalkane concentrations (>10%) was observed within 24 h when stored at room temperature. Aliphatic losses were also observed (>10%) over a 21-day holding period when samples were held at 4°C. Loss of the less sorptive analytes was demonstrated by exposing analyte solutions to greater Teflon surface areas. The demonstrated sorption of aliphatics from water samples by Teflon-lined septa indicates that the accuracy of volatile petroleum hydrocarbon determinations may be reduced by the traditional storage method. An alternative storage protocol is reported combining a lead foil septum surface and 1% (w/w) tribasic sodium phosphate dodecahydrate (Na3PO4 · 12H2O) preservative. This method prevented loss of the test analytes, including alkanes and isoalkanes for at least 21 days at room temperature.
Distribution and Transport of Selected Anthropogenic Lipophilic Organic Compounds Associated with Mississippi River Suspended Sediment, 1989–1990 by C. E. Rostad; W. E. Pereira; T. J. Leiker (pp. 248-255).
In the first study on this scale, distribution and transport of selected hydrophobic halogenated organic compounds associated with suspended sediment from the lower Mississippi River and its principal tributaries were determined during two spring and two summer cruises. Lipophilic organic compounds identified on the suspended sediment included hexachlorobenzene, pentachlorobenzene, pentachloroanisole, dacthal, chlordane (cis- and trans-), nonachlor (trans-), chlorthalonil, and penta-, hexa-, hepta-, and octachlorobiphenyls. Most of these compounds come from nonpoint sources. Mass loadings of most of the compounds increased from upstream to downstream on the main stem of the Mississippi River. Of the tributaries studied, the Ohio River had the most significant effect on contaminant loads. Suspended sediment transport to the Gulf of Mexico of the most abundant, widely distributed compound class, PCBs, was estimated at 6,750 kg per year.
Metal Content Profiles in Mushrooms Collected in Primary Forests of Latin America by D. Michelot; F. Poirier; L. M. Melendez-Howell (pp. 256-263).
Ecotoxicology and environmental safety concerns suggested estimation of the content of 14 metals—some of them highly toxic, such as cadmium, mercury, and lead—in 26 mushrooms species (Basidiomycetes and Ascomycetes). The fungi—members of different genera—were collected during two periods, 1967–1969 and 1978–1981, in primary forests of Latin America (mainly French Guyana and a few samples from Colombia and Costa Rica), these areas are non- or slightly inhabited, therefore, industrial pollution has to be considered as totally nonexistent. Heavy metals, selectively concentrated in specific living organisms, should be regarded as toxin-like substances, taking into account the bioaccumulation sites (mushrooms) and the noxious activity toward various organs of mammals (i.e., central nervous system, kidneys, liver, etc.). The levels and distribution of the metals in the samples are given and compared. Most surprisingly, contents are not especially contrasted with those found in mushrooms collected in European urban areas, such as the Paris region; cadmium, lead, and mercury levels are of the same order of magnitude.
A Comparison of the Relative Sensitivity of Structural and Functional Cellular Responses in the Alga Chlamydomonas eugametos Exposed to the Herbicide Paraquat by D. Franqueira; A. Cid; E. Torres; M. Orosa; C. Herrero (pp. 264-269).
The effect of the herbicide paraquat on the freshwater microalga Chlamydomonas eugametos was studied in function of different parameters such as growth, elemental composition, total lipids, and photosynthetic pigments content and others assayed by flow cytometry (cell viability, cell volume, and granularity). The study reveals that paraquat concentrations above 0.15 μM are toxic for the microalga C. eugametos, inducing an inhibition of all the physiological parameters analyzed and strong structural changes. However, lower concentrations cause alterations in certain cellular components that are especially sensitive to the toxic action of the herbicide; so total lipids and photosynthetic pigments content are affected by concentrations such low as 0.037 μM. Taking into account these results, these parameters are better indicators of the cellular state than data on biomass or growth rate.
Toxicity and Phototoxicity of Mixtures of Highly Lipophilic PAH Compounds in Marine Sediment: Can the ΣPAH Model Be Extrapolated? by B. L. Boese; R. J. Ozretich; J. O. Lamberson; R. C. Swartz; F. A. Cole; J. Pelletier; J. Jones (pp. 270-280).
The additivity of toxic units was tested using sediments contaminated with mixtures of highly lipophilic (log Kow > 4.5) parent and alkylated PAHs. The direct toxicity and photoinduced toxicity of these mixtures were examined in standard 10-day sediment toxicity tests using the infaunal amphipod Rhepoxinius abronius, with mortality and the survivors' ability to rebury as endpoints. Survivors of the initial 10-day tests were then exposed for 1 h to ultraviolet (UV) radiation and the results compared to initial (10-day) endpoints. Tissue residues and lipids were measured and biota-sediment accumulation factor (BSAF) values determined. The results indicated that the bioaccumulated contaminants were not initially toxic, however, they were highly phototoxic. Although the summed toxic units of these contaminants appeared to be nonadditive, additivity was not disproved as inaccuracies in extrapolating the Kow-LC50 QSAR or insufficient exposure duration might also have accounted for the observed results. Critical body residue (CBR) estimates for R. abronius were similar while BSAF values were much larger (10×) in comparison to other studies, which used amphipods and PAHs. The phototoxicity of mixtures of contaminants were similar to the phototoxicity of single contaminants when expressed on a molar basis, which suggests that phototoxicities may be roughly additive.
Hsp60-Induced Tolerance in the Rotifer Brachionus plicatilis Exposed to Multiple Environmental Contaminants by C. E. Wheelock; M. F. Wolfe; H. Olsen; R. S. Tjeerdema; M. L. Sowby (pp. 281-287).
Hsp60 induction was selected as a sublethal endpoint of toxicity for Brachionus plicatilis exposed to a water accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO), a PBCO/dispersant (Corexit 9527®) fraction and Corexit 9527® alone. To examine the effect of multiple stressors, exposures modeled San Francisco Bay, where copper levels are approximately 5 μg/L, salinity is 22‰, significant oil transport and refining occurs, and petroleum releases have occurred historically. Rotifers were exposed to copper at 5 μg/L for 24 h, followed by one of the oil/dispersant preparations for 24 h. Batch-cultured rotifers were used in this study to model wild populations instead of cysts. SDS-PAGE with Western Blotting using hsp60-specific antibodies and chemiluminescent detection were used to isolate, identify, and measure induced hsp60 as a percentage of control values. Both PBCO/dispersant and dispersant alone preparations induced significant levels of hsp60. However, hsp60 expression was reduced to that of controls at high WAF concentrations, suggesting interference with protein synthesis. Rotifers that had been preexposed to copper maintained elevated levels of hsp60 upon treatment with WAF at all concentrations. Results suggest that induction of hsp60 by chronic low-level exposure may serve as a protective mechanism against subsequent or multiple stressors and that hsp60 levels are not additive for the toxicants tested in this study, giving no dose-response relationship. The methods employed in this study could be useful for quantifying hsp60 levels in wild rotifer populations.
Uptake of 109Cd from Natural Sediments by the Blue Mussel Mytilus trossulus in Relation to Sediment Nutritional and Geochemical Composition by I. Pollet; L. I. Bendell-Young (pp. 288-294).
The objective of this study was to determine if trace metal bioavailability from suspended particulate matter (SPM) and recently deposited lake sediment (LS) to the filter-feeding bivalve Mytilus trossulus was dependent on the nutritional content and/or the geochemistry of the sediment. For SPM these characteristics are seasonally dependent; for LS they are dependent on lake chemistry and trophic status. To meet this objective, SPM was sampled from the Fraser River estuary, British Columbia, Canada, during Winter (March), spring (April, May), and summer (June, July) months. Deposited LS was sampled from an acidic dystrophic and a circumneutral, oligotrophic lake. Sediments were labeled with 109Cd, fed to M. trossulus and the amount of 109Cd accumulated over a 4-h feeding period assessed. Simultaneous extraction (separation of the sediment into easily reducible, reducible, and organic sediment components) of the radiolabeled sediments indicated that 109Cd associated with the inorganic, not the organic portion of sediment. The amount of 109Cd accumulated by the mussel over the 4-h feeding period was dependent on sediment %carbon (%C) and %nitrogen (%N) content (R2 = 0.75 and 0.52, respectively, for SPM and R2 = 0.76 and 0.64 for LS, respectively), and not on sediment concentrations of easily reducible manganese or reducible iron. These findings suggest that mussels obtain 109Cd from the inorganic portion of sediment as a consequence of digestive processes that are selecting for the carbon and nitrogen component of sediment. Hence, accumulation of cadmium from sediment will be dependent on sediment %C, and to a lesser extent %N content; however, amounts that the organism will be exposed to will depend on concentrations present on the inorganic component. Predictive models of metal accumulation by filter-feeding organisms need to consider the role of both sediment components for predicting amounts of metal that the organisms will bioaccumulate.
Selenium Bioaccumulation by the Water Boatman Trichocorixa reticulata (Guerin-Meneville) by B. V. Thomas; A. W. Knight; K. J. Maier (pp. 295-300).
The input of selenium from subsurface agricultural drainage into surface water systems can result in the accumulation of toxic concentrations of selenium in aquatic food chains. Elevated selenium concentrations in aquatic systems is a significant environmental problem in many areas of the United States. A laboratory investigation was conducted to determine the dominant route of selenium bioaccumulation by the corixid Trichocorixa reticulata, an important food chain organism. The roles of waterborne and foodborne exposure in selenium bioaccumulation were examined using 48-h bioassays. Waterborne selenium concentrations ranged from 0 to 1,000 μg Se/L as selenate. A mixture of two species of blue-green algae cultured in media with selenium concentrations ranging from 0 to 1,000 μg Se/L as selenate was used as a corixid diet in the foodborne treatments. Corixids exposed to waterborne selenate did not accumulate selenium above control concentrations. Corixids fed algae exposed to ≥100 μg Se/L as selenate had significantly higher selenium concentrations than control organisms. These data suggest that corixids may be effectively isolated from the water and selenium accumulation is solely through dietary exposure.
Morphological and Reproductive Characteristics of Male Mosquitofish (Gambusia affinis holbrooki) Inhabiting Sewage-Contaminated Waters in New South Wales, Australia by J. Batty; R. Lim (pp. 301-307).
The potential effects of exposure of fish to reproductive endocrine disruptors (REDs) is of major concern. This study reports on the effects of sewage effluent exposure on morphology of male mosquitofish (Gambusia a. holbrooki) in a tributary of the Hawksbury-Nepean River system in New South Wales, Australia. The growth and development of the modified anal fin (the gonopodium, GP) is a secondary sexual characteristic in males, forms under the influence of testosterone, and is critical for sperm transfer. The GP was reduced in length in males sampled downstream from a sewage treatment plant discharge point compared to GP fin length in males upstream or from other comparison sites. The reduction in size of this androgen-dependent structure suggests the presence of RED substances in the water. The presence or absence of spermatozeugmata (sperm packet) was not related to a reduction in GP length, which suggests spermatogenesis may not be reduced, but other measures of fertility remain to be evaluated. These results are discussed in the context of RED contaminants associated with sewage effluent.
Yolk PCB and Plasma Retinol Concentrations in Shag (Phalacrocorax aristotelis) Hatchlings by K. M. Murvoll; J. U. Skaare; V. H. Nilssen; C. Bech; J. E. Østnes; B. M. Jenssen (pp. 308-315).
To evaluate the possibilities of applying plasma retinol as a biomarker of response in seabirds exposed to chronic low levels of organochlorines, the relationship between yolk content of polychlorinated biphenyls (PCBs) and plasma retinol levels were studied in newly hatched shag chicks (Phalacrocorax aristotelis) from the coast of central Norway. The mean concentration of 29 PCB-congeners (ΣPCB) in the yolk sac was 1.22 μg/g ww (wet weight basis) (SD = 0.57, n = 10), or 17.99 ng/g lw (lipid weight basis) (SD = 6.26, n = 10). Expressed as TCDD-equivalents (ΣTEQ), the exposure in the yolk sac was 43.9 pg/g ww (SD = 19.5, n = 10), or 637.1 pg/g lw (SD = 240.8, n = 10), considerably lower than the levels that have been associated with clear-cut lethal and sublethal effects such as egg mortality, hatchability, or live deformity in Phalacrocoracidae species. There were significant negative correlations between ΣPCB ww and the variables egg volume, yolk mass, and hatchling mass. We suggest that these relationships are passive causes of a higher lipid concentration in small eggs, rather than the PCB affecting the variables. Analyses showed that there was a borderline significant positive correlation between ΣPCB lw in yolk and plasma retinol concentration. Although the results indicate that plasma retinol level alone is a poor indicator of PCB exposure in shag hatchlings, the result may be related to the low level of contaminant exposure and the low sample size of the study.
Acute Toxicity and Sublethal Effects of White Phosphorus in Mute Swans, Cygnus olor by D. W. Sparling; D. Day; P. Klein (pp. 316-322).
Among the waterfowl affected by white phosphorus (P4) at a military base in Alaska are tundra (Cygnus columbianus) and trumpeter (C. buccinator) swans. To estimate the toxicity of P4 to swans and compare the toxic effects to those of mallards (Anas platyrhynchos), we dosed 30 juvenile mute swans (C. olor) with 0 to 5.28 mg P4/kg body weight. The calculated LD50 was 3.65 mg/kg (95% CI: 1.40 to 4.68 mg/kg). However, many of the swans still had P4 in their gizzards after dying, as determined by “smoking gizzards” and characteristic odor, and a lower LD50 might be calculated if all of the P4 had passed into the small intestines. We attribute the retention of P4 in swans to the possibility that P4 pellets were mistaken for the similarly sized grit in their gizzards. Most swans took 1 to 4.5 days to die in contrast to the few hours normally required in mallards and death appeared to be related more to liver dysfunction than to hemolysis. White phosphorus affected several plasma constituents, most notably elevated aspartate aminotransferase, blood urea nitrogen, lactate dehydrogenase, and alanine aminotransferase.
Toxicity of Lead-Contaminated Sediment to Mallards by G. H. Heinz; D. J. Hoffman; L. Sileo; D. J. Audet; L. J. LeCaptain (pp. 323-333).
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).
Elevated Lead Exposure in American Woodcock (Scolopax minor) in Eastern Canada by A. M. Scheuhammer; C. A. Rogers; D. Bond (pp. 334-340).
We investigated the degree and incidence of elevated lead (Pb) accumulation in the American woodcock (Scolopax minor) in eastern Canada by measuring the concentration of Pb in undamaged wing bones of 1,588 birds from Ontario, Quebec, Nova Scotia, and New Brunswick. Overall median bone-Pb concentrations were 21 μg/g (DW) for adults and 11 μg/g for young of the year. A high proportion of birds had elevated Pb concentrations, compared with other wild bird species. Fifty-two percent of adults and 29% of young of the year had bone concentrations exceeding 20 μg/g. Pb concentration varied significantly with age, gender, and geographical region (p ≤ 0.0001). Mean Pb concentrations were lower for young of the year than for adults and lower for males than for females in both age groups. Atlantic Canada (New Brunswick and Nova Scotia) tended to have the highest frequency of individuals with elevated Pb accumulation. Potential sources of Pb exposure in woodcock include ingestion of spent lead shot from hunting, ingestion of Pb-contaminated soil, and/or ingestion of Pb-contaminated earthworms.
Longitudinal Pattern of Enzymatic and Absorptive Functions in the Small Intestine of Rats After Short-Term Exposure to Dietary Cadmium Chloride by B. Elsenhans; G. Hunder; G. Strugala; K. Schümann (pp. 341-346).
In vitro and in situ findings suggest an impairment of digestive and absorptive functions in the small intestine by enteral cadmium salts. In the rat, diets with up to 1 mmol Cd/kg are well tolerated, however, so that the impairment might not be this drastic or compensated by adaptive changes. To elucidate whether small intestinal functions are altered, we studied the effect of dietary cadmium on the longitudinal pattern of mucosal enzymes and the in vitro uptake of methyl α-D-glucoside in the small intestine of female rats. Three groups of rats were employed, a control group and two groups receiving dietary CdCl2 either at 0.3 or 1.0 mmol Cd/kg of diet. Rats were killed after 1 week of feeding. The entire small intestine was removed, rinsed with ice-cold saline and divided into 12 segments of equal length. Mucosal scrapings from each segment were used to measure mucosal cadmium levels, sucrase, lactase, alkaline phosphatase, glycylleucine-hydrolase, and diamine oxidase activities. Sugar uptake was determined in vitro in all segments using everted rings tissue accumulation method. Although cadmium levels in the mucosa were high (>100 ng Cd/mg protein or >100 μmol Cd/kg WW) most enzyme activities were only slightly changed. When significant decreases in activity were detected, they were only observed in the proximal small intestine. Sugar uptake was also impaired only in proximal segments, the maximal transport capacity was reduced by approximately 20%. These findings suggest that cadmium even at dietary levels of 1 mmol/kg do not lead to a drastic impairment of digestive and absorptive functions in the small intestine and that in the rat presently observed, mostly proximal impairments are easily compensated by unaltered distal functions. Certainly, absorption of micronutrients, for which an impaired proximal function cannot be compensated, e.g. iron, might be critical in this respect.
Estimation of Absorption of Trihalomethanes and Carbon Tetrachloride in Low-Level Exposure by Inhalation Pharmacokinetic Analysis in Rats by T. Yoshida; K. Andoh; M. Fukuhara (pp. 347-354).
Inhalation pharmacokinetics of the environmental contaminants chloroform, bromodichloromethane, chlorodibromomethane, and carbon tetrachloride were evaluated, and their absorption amounts were estimated in rats to obtain fundamental data for risk assessment of chronic low-level exposures. Measured amounts of the substances were injected into a closed chamber system in which a rat had been placed, and the concentration changes in the chamber were examined. The pharmacokinetics of the substances were evaluated on the basis of the concentration-time courses using linear or nonlinear compartment models. The metabolic elimination amounts at various exposure concentrations were extrapolated using the estimated pharmacokinetic parameters. With exposure to chloroform, the fraction of the elimination amount at 1 ppb exposure (low concentration) against the exposure concentration was estimated to be 1.1 times higher than the fraction at 10 ppm exposure (high concentration). With exposure to low concentrations (1 ppb), extrapolation showed that more chloroform (0.33 nmol/h/kg) was absorbed by the rats than chlorodibromomethane (0.11 nmol/h/kg), bromodichloromethane (0.072 nmol/h/kg), and carbon tetrachloride (0.053 nmol/h/kg). Our findings revealed differences in the absorption amounts among the substances for the same exposure concentrations.
Identification of 19 Polybrominated Diphenyl Ethers (PBDEs) in Long-Finned Pilot Whale (Globicephala melas) from the Atlantic by G. Lindström; H. Wingfors; M. Dam; B. v. Bavel (pp. 355-363).
Nineteen tetra- to hexabrominated diphenyl ethers were identified at ppb concentration in the blubber of pilot whale caught off the coast of the Faroe Islands in 1994 and 1996. Higher total concentrations were found in the pooled samples of young males (3,160 ng/g lipid) and females (3,038 ng/g lipid) compared to adult females (843 ng/g and 1,048 ng/g lipid) and males (1,610 ng/g lipids). The predominant isomers in all samples were 2,2′,4,4′-TeBDE (PBDE #47) and 2,2′,4,4′,5-PeBDE (PBDE #99) accounting for some 70% of the sum of the 19 isomers.