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Archives of Environmental Contamination and Toxicology (v.45, #4)
Potential of Solid Phase Extraction Disks to Aid Determination of Dislodgeable Foliar Residues of Chlorpyriphos, Malathion, Diazinon, and Acephate by J. C. Snyder; R. R. Thacker; M. Boeniger; G. F. Antonious (pp. 429-435).
The utility of solid phase extraction (SPE) for concentrating four organophosphate insecticides from solutions of water and sodium dioctyl sulfosuccinate, a surfactant, was evaluated. Reverse phase (C18, octadecyl bonded silica) sorbent in the form of a disk was the SPE medium evaluated. Chlorpyriphos, malathion, and diazinon, but not acephate, were retained on and eluted from the SPE disks. For pesticides that were retained on SPE disks, recoveries from the disks were equal to or higher than recoveries achieved by solvent partitioning. Dislodgeable foliar residues of acephate were successfully concentrated for analysis by lyophilization of water–surfactant solutions. Recoveries of pesticides from SPE disks stored at −15°C for one week were equal to or higher than those of pesticides stored in water–surfactant for one week at −15°C. Malathion- and diazinon-fortified samples in water–surfactant and on SPE disks were prepared in one state and shipped for analysis in another state. Pesticides in the water–surfactant samples were concentrated by solvent partitioning and were underestimated by 41% (diazinon) and 16% (malathion). Conversely, diazinon samples on the SPE disks were on average underestimated by 3% and malathion was overestimated by an average of 55%. The overestimation of malathion was attributed to a matrix effect during analysis associated with the presence of surfactant, which was retained on and subsequently eluted from the SPE disks. The retention of surfactant by the SPE disks and its subsequent elution may considerably limit their usefulness in determination of dislodgeable foliar residues.
Water Characterization and Seasonal Heavy Metal Distribution in the Odiel River (Huelva, Spain) by Means of Principal Component Analysis by C. Montes-Botella; M. D. Tenorio (pp. 436-444).
The Iberian Pyrite Belt is the largest mass of sulfide and manganese ores in Western Europe. Its sulfide oxidation is the origin of a heavily acidic drainage that affects the Odiel River in southwestern Huelva (Spain). To assess physicochemical, contamination parameters, heavy metal distribution and its seasonal variation in the upper Odiel River and in El Lomero mines, three water samplings were undertaken and analyzed between July 1998 and November 1999. Water from the Odiel River in the polluted zone showed low pH values (2.76–3.51), high heavy metal content, and high values of conductivity (1410–3648 μS/cm) and dissolved solids (1484–5602 mg/L). Principal Component Analysis (PCA) showed that variables related with the products of the pyrite oxidation and the salts that are solubilized by the high acidity generated in the oxidation of sulfides, grouped in the first component, accounted for 40.88% of total variance, and were the main influential factor in physicochemical water sample properties. The second influential factor was minority metals (nickel, cobalt, cadmium). Heavy metals showed three different seasonal patterns, closely related with saline efflorescences formed next to the river bed: majority metals (iron, copper, manganese, zinc); minority metals (lead, nickel, cobalt, cadmium); and chromium, which had a distinctive behavior.
Oxyfluorfen Toxic Effect on S. obliquus Evaluated by Different Photosynthetic and Enzymatic Biomarkers by L. Geoffroy; D. Dewez; G. Vernet; R. Popovic (pp. 445-452).
The effect of oxyfluorfen was investigated when alga Scenedesmus obliquus has been exposed to different concentrations (7.5, 15, and 22.5 μg.L−1) at 12, 24, and 48 hours of exposure. Toxicity test was done by using 13 biomarkers concerning growth rate, chlorophyll content and indicators of photosynthetic and antioxidant enzyme activities. The change of the 13 parameters showed a great variation of sensitivity indicating differences in parameters’ suitability to be used as biomarkers when alga culture was exposed to oxyfluorfen toxicity. The order of sensitivity between those biomarkers was: Antenna size (ABS/RC) > Chlorophyll content > Catalase (CAT) > Operational PSII quantum yield (ΦsPSII) > Glutathione S-transferase (GST) > Functional plastoquinone pool (QPQ) > Glutathione reductase (GR) > Growth rate > Nonphotochemical quenching (QN) > Proton gradient quenching (QEmax) > Ascorbate peroxidase (APX) > Photochemical quenching (QP) > Maximum PSII quantum yield (ΦPSII). The effect of oxyfluorfen on the changes of those parameters was interpreted as a result of herbicide mode of action at molecular level of alga cellular system. This study indicated for some photosynthetic and enzymatic biomarkers to be useful indicators of toxicity effect induced in non-target alga species. Determination of biomarkers’ sensitivity order may facilitate their selection to be used in environmental risk assessment of polluted water.
Assessment of the Probabilistic Ecological Risk Assessment-Toxic Equivalent Combination Approach for Evaluating Pesticide Mixture Toxicity to Zooplankton in Outdoor Microcosms by T. K. George; K. Liber; K. R. Solomon; P. K. Sibley (pp. 453-461).
The probabilistic ecological risk assessment-toxic equivalent (PERA-TE) combination approach was recently introduced in response to the increased demand for risk assessment approaches that can accommodate mixtures. The effectiveness and validity of the PERA-TE approach was assessed using two types of pesticide mixtures tested in outdoor microcosms. The first type of mixture consisted of pesticides with similar modes of action (the organophosphorus insecticides chlorpyrifos and diazinon) and the second of pesticides with different modes of action (chlorpyrifos, endosulfan, and trifluralin). To assess the toxicity of, and potential interaction within, each type of mixture, theoretically equitoxic TE mixtures were prepared in different proportional ratios. The TE mixtures were based on the 10th centile of acute toxicity effects distributions (data obtained from the literature) and a factor of the sum of the 90th centile field concentrations extrapolated from exposure distributions based on North American surface water monitoring data. Changes in zooplankton population abundances were used as the effect measure. The binary organophosphorus mixtures were equitoxic and conformed to the concentration addition model. The observed response trends of zooplankton exposed to the mixture of chemicals with different modes of action were a result of the susceptibility of individual taxa to the dominating pesticide in each mixture. Overall, the PERA-TE approach was not effective in predicting the toxicity and interaction of all mixture types and should be limited to assessing mixtures of chemicals with similar modes of action.
Mercury Toxicity in the Aquatic Oligochaete Sparganophilus pearsei II: Autotomy as a Novel Form of Protection
by D. E. Vidal; A. J. Horne (pp. 462-467).
Accumulation and Soluble Binding of Cadmium, Copper, and Zinc in the Polychaete Hediste diversicolor from Coastal Sites with Different Trace Metal Bioavailabilities by B. Berthet; C. Mouneyrac; J. C. Amiard; C. Amiard-Triquet; Y. Berthelot; A. Le Hen; O. Mastain; P. S. Rainbow; B. D. Smith (pp. 468-478).
Bioaccumulation of cadmium, copper, and zinc was examined in common ragworms Hediste diversicolor from control (Bay of Somme, Blackwater) and metal-rich (Seine estuary, Boulogne harbor, Restronguet Creek) sites in France and the United Kingdom. The degree of exposure in the field was assessed by considering both total concentrations in superficial sediment and the quantities of metals which may be released in vitro at different pH levels. Among the three contaminated sites, release of the three metals was not detectable in Boulogne harbor, in correlation with limited enhancement of the metal concentrations in the common ragworms from this site. Even at those sites where zinc could be released in vitro from the sediment, zinc concentrations were not enhanced in common ragworms, in agreement with previous findings indicating that the body content of this metal is regulated in H. diversicolor. At all the studied sites, bioaccumulated zinc was mainly in cytosolic form. The distribution of cadmium and copper varied according to the origin of the common ragworms, the insoluble fraction increasing with the degree of contamination (cadmium in the Restronguet Creek, copper in the Seine estuary, and even more in Restronguet Creek). In the cytosolic fraction, metals were partly linked to cytosolic heat-stable thiolic compounds (CHSTC) with molecular masses (5–6 kDa and about 12 kDa) consistent with metallothionein-like proteins (MTLP). Metal-binding to MTLP varied with the degree of contamination and with the metal studied. In contrast to many invertebrates, the presence of metal-binding CHSTC (MM about 2 kDa) other than MTLP seems to be a peculiar feature of H. diversicolor.
The Effects of pH and Dissolved Organic Carbon on the Toxicity of Cadmium and Copper to a Freshwater Bivalve: Further Support for the Extended Free Ion Activity Model by S. J. Markich; P. L. Brown; R. A. Jeffree; R. P. Lim (pp. 479-491).
The extended free ion activity model (FIAM) was developed by integrating concepts from the original FIAM into biological receptor theory, to obtain a conceptual model that more precisely quantifies the interaction of chemical species at biological receptor sites. The extended FIAM was tested by determining the acute (48 h) valve movement behavior (VMB) (measured in terms of the duration of valve opening) of the Australian freshwater bivalve, Hyridella depressa, to increasing concentrations of total Cd or Cu, in a standard synthetic water under conditions of varying pH (6.5–7.5) and/or dissolved organic carbon (as model fulvic acid (FA)) concentrations (0–11.2 mg L−1). Valve movement behavior, measured using an automated data acquisition system, was shown to be a quantifiable and rapid, real-time endpoint for assessing the toxic effects of Cd and Cu exposures. The VMB of H. depressa to Cd was independent (p > 0.05) of pH and/or model FA concentration. In contrast, the VMB of H. depressa to Cu was highly dependent (p < 0.001) on pH and/or model FA concentration; individuals were more sensitive to Cu at low pH and model FA concentrations. The VMB of H. depressa was directly proportional to the activity of the free metal ion (Cd2+), for the linear region of the concentration-response curves. In contrast, the VMB of H. depressa was a weighted function of the activities of the free metal ion and the 1:1 metal hydroxide species (i.e. 2.02 × Cu2+ + CuOH+), whereby Cu2+ had a two-fold greater binding affinity than CuOH+ at the cell membrane surface. Moreover, the results for Cd and Cu are consistent with the extended FIAM, as opposed to the original FIAM, where the result for Cu would be regarded as an exception. The extended FIAM explained 98% of the variability in VMB, whereas the original FIAM explained only 63% (i.e. an improvement of 35%). The improved predictability of organism response to Cu is relevant to advancing water quality guidelines for protecting aquatic biota.
Causes of Sediment Toxicity to Mytilus galloprovincialis in San Francisco Bay, California by B. M. Phillips; B. S. Anderson; J. W. Hunt; B. Thompson; S. Lowe; R. Hoenicke; R. Tjeerdema (pp. 492-497).
Since the San Francisco Regional Monitoring Program (RMP) sampling began, elutriate samples prepared with sediment from the Grizzly Bay monitoring station have been consistently toxic to bivalve larvae (Mytilus galloprovincialis). An investigation into the cause of toxicity was initiated with a Phase I Toxicity Identification Evaluation (TIE) using bivalve embryos. TIE results and chemical analyses of elutriate samples suggested that divalent metals were responsible for the observed toxicity. Following the initial characterization of trace metals as toxicants, additional TIEs were performed on elutriates prepared from three additional Grizzly Bay samples collected between 1997 and 2001. Additional TIEs included ethylenediamine tetraacetic acid (EDTA) treatments in a sediment-water interface (SWI) exposure system, and the use of a cation exchange column with serial elution of sample fractions with hydrochloric acid of increasing normality. EDTA significantly reduced toxicity in overlying water in the SWI system. The cation exchange column reduced both toxicity and concentrations of trace metals, and serial elution of the column added back both toxicity and specific metals contained in individual acid fractions. Chemical analyses of three elutriate samples demonstrated copper concentrations were within the range toxic to bivalves. Results of Phase I TIEs, additional Phase II treatments, SWI exposures, and metals analyses indicate the potential for metal toxicity in sediments from this estuarine site. When combined with the results of standard TIE methods, a solid-phase cation extraction and elution approach identified copper as the most probable cause of toxicity.
Bioconcentration and Biomagnification of Mercury and Methylmercury in North Sea and Scheldt Estuary Fish by W. Baeyens; M. Leermakers; T. Papina; A. Saprykin; N. Brion; J. Noyen; M. De Gieter; M. Elskens; L. Goeyens (pp. 498-508).
Total Hg and MMHg concentrations were assessed in more than 350 fish and shellfish samples. Hg concentrations in Greater North Sea fish of prey range from 0.039 mg kg−1 wet weight (ww; for ray) to 0.61 mg kg−1 ww (for dogfish) and for all other fish species, from 0.045 mg kg−1 ww (for plaice) to 0.33 mg kg−1 ww (for sand sole), with 95 ± 2% of the Hg content in the MMHg form. In Belgian coastal zone, fish concentrations range from 0.063 mg kg−1 ww for plaice to 0.13 mg kg−1 ww for flounder, with 82–87% of the Hg content in the MMHg form. In fish of the Scheldt, which is a very polluted estuary, Hg levels, as well as the percent MMHg of the total Hg, were lower than in the two zones previously mentioned. The intraspecies variability is of the order of 50% in each of the three zones. In liver tissue, a much larger variability was observed than in muscle tissue, except for fish species of the Scheldt. In most cases, the MMHg fraction in a particular fish species is inversely related to the intraspecies variability. Bioconcentration and biomagnification factors (BCF and BMF, respectively) were assessed. MMHg-BMFs were a few orders of magnitude higher than Hg(inorganic)-BMFs, and for the same species were always highest in the Greater North Sea and lowest in the Scheldt. For each of the Belgian coastal zone four species, a weak positive correlation between Hg content and fish length was found; however, the larger the size-range, the better the correlation.Taking fish length into account, a statistically significant difference in contamination level was observed for species sampled from the different geographical zones.
Bioavailability and Toxicity of Freshly Neutralized Aluminium to the Freshwater Crayfish Pacifastacus leniusculus by E. Alexopoulos; C. R. McCrohan; J. J. Powell; R. Jugdaohsingh; K. N. White (pp. 509-514).
Freshly neutralized aluminium (Al) is toxic to a variety of freshwater organisms despite its insolubility at circumneutral pH. Insoluble Al acts exogenously—for example, on the fish gill—thereby impairing respiratory function, and endogenously in grazing and filter-feeding invertebrates following ingestion during drinking and feeding. This paper examines the bioavailability and behavioral toxicity of freshly neutralized Al to the freshwater crayfish Pacifastacus leniusculus exposed to 500 μg L−1 added Al for 20 days under controlled conditions. We test the hypothesis that aqueous Al is toxic to the crayfish and that this is largely due to the metal’s association with the gill rather than following accumulation in the body. Little Al was accumulated in the digestive gland (hepatopancreas) or flexor muscle, but large amounts were associated with the gills, resulting in concentration factors of up to 1 × 104. Histochemistry showed that much of this metal was extracellular to the gill epithelium and associated with the mucus layer. Behavioral dysfunction was observed following exposure to Al for five days. Reduction in the amount of Al in the water column, due to binding to snail trail mucus attached to the substrate, reduced the amount of Al associated with the gill and delayed the onset of behavioral dysfunction. We conclude that freshly neutralized Al is toxic to the crayfish and that main site of Al action is the gill.
Chemobehavioral Changes Induced by Short-Term Exposures to Prochloraz, Nicosulfuron, and Carbofuran in Goldfish by P. Saglio; S. Bretaud; E. Rivot; K.H. Olsén (pp. 515-524).
The behavioral effects of short periods (2, 4, 6, 8 h) of static exposure to prochloraz (imidazole fungicide) and nicosulfuron (sulfonylurea herbicide) were recorded in goldfish (Carassius auratus). Observations were also made in an olfactometer to assess the effects of 8-h exposures to these two pesticides and to carbofuran (carbamate insecticide) on the behavioral responses to the flow of a solution of four L-amino acids (glycine, alanine, valine, taurine), mixed in the same relative proportions as in the urine of conspecifics. Each pesticide was tested at three sublethal concentrations (25, 50, 100 μg/L), and the behaviors recorded were related to swimming pattern, social interactions, and comfort movements. Static exposures to prochloraz affected horizontal displacements, burst swimming, grouping, and buccal movements. Static exposures to nicosulfuron affected burst swimming and grouping. In pesticide-unexposed fish (control), the flow of the amino acid solution induced attraction, decreased sheltering, and increased horizontal displacements, burst swimming, buccal movements, and antagonistic interactions. Compared to the controls, some of the behavioral responses to the solution of amino acids were significantly different after 8 h of subacute exposure to prochloraz and carbofuran. Both pesticides decreased attraction and increased sheltering. In addition, carbofuran decreased buccal movements and antagonistic interactions. Contrastingly, exposure to nicosulfuron showed no significant effect. This study further confirms the great vulnerability of fish behavior and chemocommunication processes to exposure to waterborne pesticides.
Impacts from PCB Accumulation on Amphibians Inhabiting Streams Flowing from the Paducah Gaseous Diffusion Plant by C. J. DeGarady; R. S. Halbrook (pp. 525-532).
Contamination at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky, has been under evaluation for many years. We studied amphibians in selected outfalls (drainage ditches) flowing from the PGDP to determine if PCBs were accumulating in their tissues and how this might affect local populations. We determined relative amphibian species richness and abundance among seven outfalls and three reference streams by listening to their calls during audio surveys. We also captured amphibians from each study site during the summers of 2000 and 2001 and analyzed their carcasses for PCBs (Aroclor 1260 and 34 congeners) and livers for ethoxyresorufin O-deethylase (EROD) activity, a biomarker of PCBs and other organic contamination. Ten species were heard across study sites, and abundance and richness at outfalls were similar to those observed at reference sites. However, there were significant differences in abundance (p = 0.001) and richness (p = 0.048) of amphibians between continuously flowing and intermittent outfalls. There were no significant differences in PCB concentrations (p = 0.113) in amphibians captured from study sites, although Aroclor 1260 concentrations tended to be higher in amphibians collected from one outfall (outfall 12) on the east side of the plant (¯X = 1260 μg/kg) compared with all other study sites (¯X = 489 μg/kg). EROD activity measured in the liver was not indicative of Aroclor 1260 concentrations in amphibians at the PGDP, and EROD did not differ by study site, species, age class, or gender. PCB concentrations measured in amphibians at the PGDP were similar to concentrations measured at reference sites and did not appear to negatively affect individual amphibians or abundance and richness.
Oxidative Stress in Laboratory-Incubated Double-Crested Cormorant Eggs Collected from the Great Lakes by K. Hilscherova; A. Blankenship; K. Kannan; M. Nie; L. L. Williams; K. Coady; B. L. Upham; J. E. Trosko; S. Bursian; J. P. Giesy (pp. 533-546).
Double-crested cormorant (Phalacrocorax auritus) eggs were collected in 1998 from three sites on Lakes Huron and Superior and either analyzed for 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)-like residues or artifically incubated. Some of the incubated eggs were injected with vitamin E (antioxidant) or piperonyl butoxide (CYPIA blocker) to examine the role of CYPIA and oxidative stress in normal bird development. Embryos (day 23) were analyzed for hepatic ethoxyresorufin O-deethylase (EROD) activity and different measures of oxidative stress. Glutathione-related parameters were also measured in brain. In contrast to the historical data, there were no statistically significant differences in concentrations of chlorinated dioxins, furans, dioxin-like PCBs, or total TCDD-equivalents (TEQs) in eggs among sites. Survival and incidence of abnormalities were comparable at all study sites. Slight differences in liver, heart, and egg weight were observed among sites. A greater incidence of eye deformities was observed in embryos treated with vitamin E. Treatment with the CYPIA blocker, piperonyl butoxide, decreased the body weights of embryos. EROD activities were similar at all locations, but measures of oxidative stress varied among locations. There were greater levels of oxidized glutathione and oxidative DNA damage at Little Charity Island in Saginaw Bay. There was relatively great interindividual variation in biochemical responses and significant interrelation of the parameters of oxidative stress. While exposure to PCDD/DF and PCBs does not seem to explain the observed oxidative stress, the potential of these compounds to cause the observed effects can not be completely excluded.
Congener-Specific Patterns and Toxic Assessment of Polychlorinated Biphenyls in Resident and Migratory Birds from Southern India and Lake Baikal in Russia by T. Kunisue; M. Watanabe; A. Subramanian; A. M. Titenko; S. Tanabe (pp. 547-561).
Concentrations of polychlorinated biphenyls (PCBs), including non-, mono-, and di-ortho congeners, were determined in migratory and resident birds collected from India and Lake Baikal in Russia. In the 11 different species examined, total PCBs concentrations were in the range of 11–4500 ng/g (wet wt). IUPAC 105, 118, 138, 153, and 180 were the predominant congeners in almost all the birds. White-cheeked tern collected from India and common tern collected from Lake Baikal showed high PCBs concentrations of 4400 ng/g (wet wt) and 4500 ng/g (wet wt), respectively, and accumulated relatively high ratios of penta-CBs (IUPAC 118, 105, 99). Toxic equivalents (TEQs) of non- and mono-ortho PCB congeners in birds collected from India and Lake Baikal were in the range of 1.5–56 and 2.8–370 pg/g wet wt, respectively. Toxic assessment results led by calculated TEQs of the transfer to eggs from female birds revealed that TEQs in most of migratory and resident birds were comparable to the lowest observable effect level (LOAEL) of chicken which is a highly sensitive species against dioxin-like compounds. Calculated transfer TEQs to eggs of common tern collected from Lake Baikal in autumn, however, exceeded the LOAEL of CYP1A induction in bald eagle embryos and ED50 of that in pheasant embryos, suggesting that embryo toxicity by coplanar PCBs in some avian species breeding in Lake Baikal is possible.
Mercury Residues in Livers of Bald Eagles (Haliaeetus leucocephalus) Found Dead or Dying in British Columbia, Canada (1987–1994) by S. A. Weech; L. K. Wilson; K. M. Langelier; J. E. Elliott (pp. 562-569).
Postmortem examinations were conducted on 82 bald eagles (Haliaeetus leucocephalus) found dead or dying in British Columbia, Canada, from 1987 to 1994. As part of the examination, livers were analyzed for total mercury (Hg) content, as well as methylmercury (meHg) and selenium (Se) in selected individuals. In total, 67 eagles were classed as having low Hg exposure [total Hg liver residues ranging from 0.5 to 17.2 mg/kg dry weight (dw)]. Fourteen eagles were moderately exposed (liver residues ranging from 19.2 to 36.8 mg/kg Hg dw). One eagle was judged to have died of Hg poisoning, with a total liver Hg content of 130.3 mg/kg dw, of which approximately 77% was meHg. The poisoned eagle and most of the exposed eagles were found in locations where effluent from pulp and paper processing plants is discharged along the British Columbia coast. In total, 6% of eagles examined died as a result of acute metal toxicosis (one from Hg poisoning, four from lead poisoning), in comparison to 72% dying from trauma (electrocution, vehicle/power line collision, eagle attack, trap, gunshot, drowning, and asphyxiation) and 11% from disease. The cause of death was undetermined in the remaining 11% of eagles.