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Archives of Environmental Contamination and Toxicology (v.60, #3)
Determination of Antibiotics in Brazilian Surface Waters Using Liquid Chromatography–Electrospray Tandem Mass Spectrometry by Marco Antonio F. Locatelli; Fernando F. Sodré; Wilson F. Jardim (pp. 385-393).
A liquid chromatography–electrospray tandem mass spectrometry (LC–MS/MS) method for the determination of antibiotics in water was developed and applied to Brazilian surface waters. Amoxicillin, ampicillin, cefalexin (CEF), ciprofloxacin (CIP), norfloxacin (NOR), sulfamethoxazole, tetracycline (TET), and trimethoprim were selected as target compounds due to their high consumption pattern in Brazil. LC and MS conditions were optimized to produce the maximum analytic response for each compound. Anion exchange and polymeric solid-phase extraction cartridges, in series, were employed during the extraction procedures. Recovery, linear range, limit of detection (LOD), and limit of quantification were calculated. LOD varied from 0.13 ng L−1 for CIP and NOR to 0.76 ng L−1 for TET. Surface water samples from the Atibaia watershed (São Paulo State, Brazil) were analyzed. Results showed that seasonal and anthropogenic aspects dictated the levels of antibiotics in the samples. An overall frequency of detection of 55% was observed during the rainy period, whereas a higher percentage (88%) was noticed for samples collected during the dry season. In the Atibaia River, sample concentrations ranged from 29 ng L−1 for CEF to 0.5 ng L−1 for NOR. In a sewage-affected stream, however, concentrations up to 2422 ng L−1 CEF were found.
Mercury Distribution and Methylmercury Mobility in the Sediments of Three Sites on the Lebanese Coast, Eastern Mediterranean by Carine Abi-Ghanem; Khaled Nakhlé; Gaby Khalaf; Daniel Cossa (pp. 394-405).
Mercury (Hg) contamination in coastal sediments has been widely studied in clay deposits; however, equivalent results on carbonated sediments are scarce. This article aims to study Hg distribution in Lebanese carbonate coastal marine sediments (Eastern Mediterranean) in order to characterize their contamination level and to explore the postdepositional mobility of methylmercury (MeHg) in the deposits. Vertical distribution profiles of total (HgT) and MeHg have been established for the solid phase of sediment cores collected in various near-shore environments chosen for their hypothetical various degrees of anthropization. In addition, dissolved MeHg was determined in sediment pore waters to test its mobility and potential availability for biota. Three sites on the Lebanese coasts—Akkar, Dora, and Selaata—were selected. Akkar is far from any direct contamination source, whereas Dora, located near the Beirut harbor, is a heavily urbanized and industrialized zone including a huge dump site, and Selaata is near a chemical plant that produces phosphate fertilizers. Particulate HgT concentrations in the sediments varied between <0.04 and 0.65 μg/g, with a proportion of MeHg lower than 1%. Based on a sediment quality guideline (MacDonald et al. 2000), we concluded that Dora bay sediments are heavily contaminated by Hg, with concentrations exceeding the “consensus-based threshold effect” level (0.17 μg/g) and almost reaching the “effects range-medium” level (0.71 μg/g). In spite of the low HgT concentration in Akkar and Selaata sediment (similar to natural carbonated sediment: 0.04 μg/g according to Turekian and Wedephol (1961), a closer analysis of the sediment core vertical profile allows one to observe an anthropogenic impact. This impact might be toxicologically insignificant; however, it allows tracing the time increase of Hg diffuse deposition. On the other hand, dissolved MeHg concentrations ranged from 0.04 to 0.09 and from 0.04 to 8.76 ng/l in the Selaata and the Dora sediments, respectively; MeHg vertical profiles in interstitial water enabled us to calculate diffusive fluxes of MeHg from the sediment varying from 0.3 to 1.0 ng/m2/day. Thus, the deposited sediments constitute a measurable source of bioavailable Hg for epibenthic organisms.
Suppression of Chlorella vulgaris Growth by Cadmium, Lead, and Copper Stress and Its Restoration by Endogenous Brassinolide by Andrzej Bajguz (pp. 406-416).
Brassinosteroids play a significant role in the amelioration of various abiotic and biotic stresses. In order to elaborate their roles in plants subjected to heavy metals stress, Chlorella vulgaris cultures treated with 10−8 M brassinolide (BL) were exposed to 10−6–10−4 M heavy metals (cadmium, lead and copper) application. Under heavy metals stress, the growth and chemical composition (chlorophyll, monosaccharides, and protein content) have been decreased during the first 48 h of cultivation. The inhibitory effect of heavy metals on C. vulgaris cultures was arranged in the following order: copper > lead > cadmium. C. vulgaris cultures treated with BL in the absence or presence of heavy metals showed no differences in the endogenous level of BL. On the other hand, treatment with heavy metals results in BL level very similar to that of control cell cultures. These results suggest that the activation of brassinosteroids biosynthesis, via an increase of endogenous BL, is not essential for the growth and development of C. vulgaris cells in response to heavy metals stress. Simultaneously, BL enhanced the content of indole-3-acetic acid, zeatin, and abscisic acid in cultures treated with heavy metals. Levels per cell of chlorophylls, protein, and monosaccharides are all increased by BL treatment when compared to nontreated control cells. Application of BL to C. vulgaris cultures reduced the accumulation of heavy metals stress on growth, prevented chlorophyll, monosaccharides, and protein loss, and increased phytochelatins content. The arrested growth of C. vulgaris cells treated with heavy metals was restored by the coapplication of BL. It suggested that BL overcame the inhibitory effect of heavy metals. From these results, it can be concluded that BL plays the positive role in the alleviation of heavy metals stress.
Toxicity of the Insecticide Terbufos, its Oxidation Metabolites, and the Herbicide Atrazine in Binary Mixtures to Ceriodaphnia cf dubia by Catherine B. Choung; Ross V. Hyne; Mark M. Stevens; Grant C. Hose (pp. 417-425).
The acute toxicity of terbufos and its major metabolites, tested alone, in binary mixtures or in combination with atrazine were evaluated using neonates of the cladoceran Ceriodaphnia cf dubia. Terbufos, terbufos sulfoxide, and terbufos sulfone tested individually were highly toxic to C. cf dubia, with mean 96-h EC50 values of 0.08, 0.36, and 0.19 μg/l, respectively. The addition of atrazine (10 μg/l) significantly increased the toxicity of terbufos. The toxicity of terbufos sulfone was unaffected by atrazine, whereas the results for terbufos sulfoxide were equivocal. Equitoxic mixtures of the metabolites showed additive toxicity to C. cf dubia. The high toxicities of terbufos and its environmentally persistent oxidative metabolites suggest that contamination of aquatic systems with this insecticide mixture and the coapplied herbicide atrazine might pose a greater hazard to some biota than their individual toxicities.
Impact of Metals on Macroinvertebrate Assemblages in the Forgotten Stretch of the Rio Grande by Catalina Ordonez; Vanessa L. Lougheed; Jorge L. Gardea-Torresdey; Lisa J. Bain (pp. 426-436).
The objective of this study was to examine how changes in the benthic macroinvertebrate community structure and a variety of abiotic variables, such as conductivity and sediment metal concentrations, are modified along the Forgotten River stretch of the Rio Grande. This stretch receives industrial effluent, raw sewage, and agricultural return flow from the El Paso (TX, USA)–Ciudad Juárez (CHI, Mexico) metroplex and then flows relatively undisturbed for 320 km before its next significant input. The high degree of use, followed by the 320-km undisturbed stretch, makes the Forgotten River a unique study site to examine downstream attenuation of contaminants and other abiotic variables to determine their potential effects on macroinvertebrates. Five different sites along the Forgotten Stretch were sampled over a 2-year period. Metal concentrations were low throughout the stretch and were predominantly correlated to percent sediment organic matter rather than explained spatially. Several sensitive invertebrate species, such as Leptophlebiidae, increased in relative abundance downstream, whereas the percentage of tolerant invertebrates decreased. Nonmetric multidimensional scaling separated the macroinvertebrate communities upstream from those downstream, with the more sensitive species being found predominantly downstream and more tolerant taxa associated upstream. Additionally, there was a distinct seasonal gradient to the community. The most important drivers of the community assemblage appear to be distance downstream and seasonality, as well as water conductivity and concentrations of sediment cadmium, which was the only metal that exceeded protective criteria. This study did not provide evidence of the downstream attenuation of heavy metals in the sediments in the Forgotten Stretch; however, downstream changes in macroinvertebrates toward more sensitive taxa suggests that other, unmeasured contaminants might be affecting biological communities in this isolated stretch of an international waterway.
Mercury-Contaminated Sediments Affect Amphipod Feeding by Mirco Bundschuh; Jochen P. Zubrod; Frank Seitz; Michael C. Newman; Ralf Schulz (pp. 437-443).
A 125-mile reach of the South River, Virginia, was contaminated with mercury during the first half of the 20th century. As increased concentrations of mercury have persisted, researchers have carefully studied its distribution in the river biota and estimated associated risks. The present study evaluated the influence of mercury on feeding rate and uptake by the amphipod Hyalella azteca. The test organisms were exposed for 7 days with leaf discs to reference and contaminated field sediment during the preliminary experiment and additionally to Sedimite (a commercial mercury-sequestering agent) amended sediments during the final experiment. The preliminary experiment demonstrated a decreased feeding rate (approximately 35%) of H. azteca in sediment from a contaminated site relative to sediment from a reference site. The test design of the final experiment took advantage of the knowledge gained in the preliminary experiment by increasing the number of replicates, which decreased the type II error rate. First, the results of the final experiment confirmed the results of the preliminary experiment by again demonstrating differences in the feeding rate of approximately 35% between reference and contaminated sediment. Second, the results indicated a lower feeding rate in reference sediment in the presence of Sedimite. Third, an opposite tendency, although not significant, was apparent for Sedimite-amended contaminated sediment. Thus, Sedimite appears to decrease sediment quality, whereas this conclusion is based on the feeding rate of H. azteca. However, Sedimite and its value as a mercury-sequestering agent requires further evaluation.
Effects of Cadmium on Locomotor Activity Rhythms of the Amphipod Gammarus aequicauda by P. S. Morillo-Velarde; J. Lloret; A. Marín; F. J. Sánchez-Vázquez (pp. 444-451).
Behavioural responses are linked to complex biochemical and physiologic changes and may act as sensitive indicators of the sublethal effects of pollutants. This article investigates changes in the locomotor activity rhythms of the amphipod Gammarus aequicauda exposed to cadmium (Cd) as a model to study the effect of pollutants on an ecologically important species. Under a 12:12 h light-to-dark cycle, G. aequicauda showed a strict nocturnal rhythm, with 90.2 ± 0.4% of their total daily activity occurring during the night. Under constant darkness, circadian rhythms persisted for 10 days, with a mean periodicity of 24.32 h, thus confirming endogenous control. Exposure to sublethal concentrations of Cd (0.16, 0.20, 0.24, and 0.28 mg l−1) did not change the nocturnal activity patterns of G. aequicauda, although their swimming activity during the night was significantly decreased by exposure to concentrations of 0.24 and 0.28 mg Cd l−1. In conclusion, locomotor activity bioassays using the amphipod G. aequicauda appeared to be a sensitive indicator of Cd contamination, and sensitivity and tolerance to Cd in short-term bioassays may depend on the time of the day tests are carried out. These results provide further support for the idea that behavioural end points in amphipods are useful indicators of pollutant exposure and that future studies should take circadian rhythms into consideration.
Assessment of Ametryn Contamination in River Water, River Sediment, and Mollusk Bivalves in São Paulo State, Brazil by Analu Egydio Jacomini; Plínio Barbosa de Camargo; Wagner Eustáquio Paiva Avelar; Pierina Sueli Bonato (pp. 452-461).
São Paulo state, Brazil, is one of the main areas of sugar cane agriculture in the world. Herbicides, in particular, ametryn, are extensively used in this extensive area, which implies that this herbicide is present in the environment and can contaminate the surface water by running off. Thereby, residues of ametryn were analyzed in samples of river water an river sediment and in freshwater bivalves obtained from the rivers Sapucaí, Pardo and Mogi-Guaçu in São Paulo State, Brazil. Samples were taken in the winter of 2003 and 2004 in two locations in each river. The specimens of freshwater bivalves collected and analyzed were Corbicula fluminea, an exotic species, and Diplodon fontaineanus, a native species. Additionally, the evaluation of the ability of bioconcentration and depuration of ametryn by the freshwater bivalve Corbicula fluminea was also performed. Ametryn concentrations in the samples were measured by liquid chromatography coupled to mass spectrometry. Residues of ametryn in water (50 ng/L) and in freshwater bivalves (2–7 ng/g) were found in the Mogi-Guaçu River in 2004, and residues in river sediments were found in all rivers in 2003 and 2004 (0.5–2 ng/g). The observation of the aquatic environment through the analysis of these matrixes, water, sediment, and bivalves, revealed the importance of the river sediment in the accumulation of the herbicide ametryn, which can contaminate the biota.
Effects of Cypermethrin (Pyrethroid Insecticide) on the Valve Activity Behavior, Byssal Thread Formation, and Survival in Air of the Marine Mussel Mytilus galloprovincialis by Mohamed Ait Ayad; Mohamed Ait Fdil; Abdelfattah Mouabad (pp. 462-470).
Cypermethrin is a pyrethroid pesticide widely used to combat agricultural pests. However, little information is available about its toxicity in aquatic macroinvertebrates in the context of the Moroccan coastline. In this study, a suite of physiological and behavioral biomarkers for water quality surveillance using mussels are used to characterize the toxicity of Cypermethrin. In these tests, sublethal effects on valve activity behavior, byssal thread formation, and survival in air of the mussel Mytilus galloprovincialis were assessed in short-term exposure. The results show that Cypermethrin impaired the valve activity in a concentration-dependent manner, leading to a reduction in the time of normal opening. The lowest effect concentration was determined as 100 μg/l Cypermethrin. Prolonged closures of mussels were also observed for the exposures to 400 and 800 μg/l. The delay to the first detection of the pesticide was concentration dependent. The capacity to produce new byssus threads in a Cypermethrin exposure was inhibited at all concentrations and especially at high concentrations. Survival in air was not affected even at 800 μg/l Cypermethrin.
In Vivo Biomarkers of Estrogenicity: Limitation of Interpretation in Wild Environment by S. Nadzialek; S. Depiereux; S. N. M. Mandiki; Patrick Kestemont (pp. 471-478).
In the literature, multiple sample schemes have been developed to assess the environmental impacts of endocrine-disruptor compounds (EDCs) from sewage treatment plant (STPs). In the present work, the plan study was designed by sampling upstream and downstream wild populations of gudgeons from two STP stations (La Roche and Rochefort, Belgium). Biomarkers of feminization were assayed, such as vitellogenin expression and ovotestis screening. Parameters involved in steroidogenesis (sex steroids and brain aromatase activity) were also investigated to better characterize interactions between living organisms coping with a complex mixture of compounds loaded by treated effluent. Results displayed moderate differences between upstream and downstream populations of wild gudgeons. Moreover, accounted differences have demonstrated the difficulty of characterizing the mixture of compounds to which fish are exposed in the aquatic milieu. Actually, physiological responses were not representative of a particular group of EDC (e.g., estrogenlike compounds) but instead confirm an association between different categories of compounds. Even if powerful biomarkers of estrogenicty were developed, the interpretation of the response profile remains limited through in vivo parameters due to the complex association between compounds of various origins.
Chronic Exposure and Decontamination of a Marine Sculpin (Myoxocephalus scorpius) to Polychlorinated Biphenyls Using Selected Body Indices, Blood Values, Histopathology, and Parasites as Bioindicators by R. A. Khan (pp. 479-485).
This study was conducted to assess the health of a subtidal marine sculpin, Myoxocephalus scorpius, naturally exposed in a shipping terminal where polychlorinated biphenyls (PCBs) had been spilled, as well as that of others sculpins after decontamination in the laboratory for 16 weeks. Reference samples were captured at a pristine site upcurrent from the contaminated terminal. Examination of field samples caught by scuba divers showed external and toxicopathic lesions in several tissues; decreased body condition and organ indices; and decreased hemoglobin and lymphocyte levels. No difference in the diversity of parasites was observed between reference and contaminated samples, but abundance was generally greater in fish from the latter site. Although the total number of species of parasites decreased in both groups of depurated sculpins, the abundance of infections on gill and gall bladder was significantly greater in fish from the polluted site. These results suggest that M. scorpius was affected adversely by PCBs and that its responses are ecologically significant as a bioindicator species in degraded habitats. Moreover, remediation might not mitigate the observed anomalies in fish inhabiting the impacted site.
Mercury Concentrations in Water and Hybrid Striped Bass (Morone saxatilis × M. chrysops) Muscle Tissue Samples Collected from the Ohio River, USA by Erich B. Emery; John P. Spaeth (pp. 486-495).
We report on long-term aqueous mercury (Hg) measurements collected at fixed locations along the Ohio River, offer insights into patterns of water and fish tissue Hg levels, and calculate site-specific bioaccumulation factors (BAFs) along an extensive longitudinal basis. We examined the relationship between total recoverable Hg concentrations in water and fish samples collected from 12 locations on the mainstem Ohio River. Water samples were collected on a bimonthly basis from each location over a 6-year period preceding the collection of fish tissue samples. This abundance of data enabled us to calculate the long-term average aqueous Hg concentrations and approximate the lifetime aqueous Hg exposure experienced by fish, enabling the calculation of appropriate BAFs. Hybrid striped bass (HSB; Morone saxatilis × M. chrysops) were collected from the Ohio River, composited (three fish), and analyzed for Hg in muscle tissue from each location. Concentrations ranged from 0.2 to 0.4 mg/kg and 41.7% of all samples collected were higher than the US Environmental Protection Agency regulatory threshold of 0.3 mg Hg/kg wet weight. Hg levels generally increased with fish weight, length, and age. However, Hg concentration in the water was the strongest predictor of tissue concentrations. We found that both water and tissue concentrations increased with drainage area, albeit at different rates. This discrepancy in spatial patterns revealed that the bioaccumulation rate of methylmercury might not be consistent throughout the Ohio River mainstem. BAFs calculated at each location supported this finding, as values decreased with increasing drainage area. Our study serves to fill critical, previously identified data gaps and provides decision-makers with the information necessary to develop more appropriate BAF development and risk-management strategies.
Mercury Concentrations in Largemouth Bass (Micropterus salmoides) Collected from Ash Meadows National Wildlife Refuge, Nye County, Nevada by Shawn Goodchild; Shawn Gerstenberger (pp. 496-500).
Mercury is a known neurotoxin and contaminant of concern worldwide. Mercury may occur at elevated concentrations adjacent to industrial sources, such as coal-fired power plants, or in remote environments and newly filled water bodies. Mercury tissue concentrations were determined for a sample of largemouth bass (Micropterus salmoides) from Crystal Reservoir, Ash Meadows National Wildlife Refuge, Nye County, Nevada. This investigation was triggered by (1) the presence of several conditions in soil and water that facilitate mercury bioaccumulation, (2) previous investigations that detected mercury in source springs, and (3) the presence of game fish and endangered pupfish within the reservoir. Mercury concentrations were significantly correlated with both fish mass and condition, but were lower than national human health and safety standards. It is possible that high pH and salinity inhibited methylation and subsequent bioaccumulation; however, additional studies are needed to determine causation of the low concentration in fish tissue compared with ambient conditions.
Reproductive Consequences of Exposure to Waterborne Phytoestrogens in Male Fighting Fish Betta splendens by Louise M. Stevenson; Alexandria C. Brown; Tracy M. Montgomery; Ethan D. Clotfelter (pp. 501-510).
Phytoestrogens are plant compounds that can act as endocrine disruptors in vertebrates. Biologically active levels of phytoestrogens have been found in aquatic habitats near wood pulp and paper mills, biofuel manufacturing plants, sewage-treatment plants, and agricultural fields. Phytoestrogens are known to cause hormonal and gonadal changes in male fish, but few studies have connected these effects to outcomes relevant to reproductive success. In one experiment, we exposed sexually mature male fighting fish Betta splendens to environmentally relevant (1 μg L−1) and pharmacological concentrations (1000 μg L−1) of the phytoestrogen genistein as well as to a positive control of waterborne 17β-estradiol (E2; 1 μg L−1), and a negative control of untreated water. In a second experiment, we exposed male B. splendens to environmentally relevant concentrations (1 μg L−1) of genistein and β-sitosterol singly and in combination as well as to the positive and negative controls. All exposures were 21 days in duration. We measured sex-steroid hormone levels, gonadosomatic index (GSI), sperm concentration and motility, and fertilization success in these fish. We found that exposure to genistein did not affect circulating levels of the androgen 11-ketotestosterone or the estrogen E2 relative to negative-control fish. We also found that neither of the compounds nor their mixture affected GSI, sperm concentration or motility, or fertilization success in exposed fish relative to negative-control fish. However, fish exposed to phytoestrogens showed some evidence of fewer but more motile sperm than fish exposed to the positive control E2. We conclude that sexually mature male B. splendens are relatively immune to reproductive impairments from short-term exposure to waterborne phytoestrogens.
Subchronic Toxic Effects of Fluoride Ion on the Survival and Behaviour of the Aquatic Snail Potamopyrgus antipodarum (Hydrobiidae, Mollusca) by Álvaro Alonso; Julio A. Camargo (pp. 511-517).
Short-term bioassays usually assess lethal effects of pollutants in animals, whereas subchronic bioassays are more suited for assessing effects on animal behaviour. Among them, videotaped bioassays are an improvement in the behavioural monitoring because they are easily and cheaply implemented. The present study focuses on the assessment of subchronic (14-day) effects of fluoride ion on the survival, proportion of dead plus immobile animals, and velocity (monitored by a videotaping and image analysis system) of the aquatic snail Potamopyrgus antipodarum (Hydrobiidae, Mollusca). One control and three nominal fluoride concentrations (5, 20, and 40 mg F−/l [actual mean concentrations of 5.2, 17.5, and 37.0 mg F−/l, respectively]) were used. Each treatment (including the control) was replicated 12 times. Mortality, number of dead plus immobile animals, and velocity were monitored after 0, 7, and 14 days of exposure. After 14 days, animals exposed to 40 mg F−/l showed higher mortality, number of dead, and immobile individuals than control animals. Snails exposed to 5 and 20 mg F−/l were not affected by fluoride ion regarding these endpoints. In contrast, snails exposed to 20 mg F−/l for 7 and 14 days showed lower velocity than control animals. Therefore, velocity was sensitive to environmental fluoride concentrations and as such is a useful parameter for ecologic risk assessment. In addition, videotaping allowed us to detect behavioural patrons in velocity at very short exposures (seconds) during the monitoring process by showing that the velocity of snails must be monitored at least during the course of several minutes. We conclude that in P. antipodarum, velocity is a more sensitive endpoint than the classic mortality and immobility endpoints.
Prey Species as Possible Sources of PBDE Exposures for Peregrine Falcons (Falco peregrinus) Nesting in Major California Cities by June-Soo Park; Alison Fong; Vivian Chu; Arthur Holden; Janet Linthicum; Kim Hooper (pp. 518-523).
Our earlier findings indicate that (1) peregrine falcons (Falco peregrinus anatum Bonaparte) nesting in major California cities have among the highest polybrominated diphenyl ether (PBDE) levels in the world (max ∑PBDEs = 100 ppm), and (2) Big City peregrines have higher levels and proportions of the higher-brominated congeners (hepta- to deca-BDEs) than do their Coastal counterparts. In this study we classified the prey species (n = 185) from the remains of prey (feathers) at 38 peregrine nest sites over 25 years (1974–1998). We grouped the prey species into 15 categories based on diet and found distinctly different prey patterns for Big City vs. Coastal peregrines. Big City peregrines had a higher (almost three times) weight percentage intake of food waste-eating birds (e.g., rock pigeons, Columba livia) than Coastal peregrines. These differing prey patterns suggest diet as a potential source of the unusually high levels and proportions of higher-brominated PBDEs in Big City peregrines. The relative contributions of diet and dust (e.g., preening) exposure to PBDE patterns in Big City peregrines will be explored in future investigations.
Concentrations of Selected Heavy Metals in Bones and Femoral Bone Structure of Bank (Myodes glareolus) and Common (Microtus arvalis) Voles from Different Polluted Biotopes in Slovakia by M. Martiniaková; R. Omelka; A. Jančová; R. Stawarz; G. Formicki (pp. 524-532).
Concentrations of selected heavy metals in the femora and femoral bone structure of bank (Myodes glareolus) and common (Microtus arvalis) voles from different polluted biotopes in Slovakia (Kolíňany and Nováky sites) were investigated. Length, weight, and histological structure of vole bones were also analyzed. We observed higher concentrations of lead (Pb), iron (Fe), copper (Cu), and zinc (Zn) in the bones of both species from the Kolíňany site. Significant differences were observed in the concentration of Fe in bank and common voles (p < 0.05) and in the concentration of Zn (p < 0.05) in common voles. The animals from Nováky had higher concentrations of cadmium (Cd) and nickel (Ni) in their bones; however, the differences were not significant. The measured values for bone length and weight were higher in both species from Nováky (p < 0.05). We did not identify differences in qualitative histological characteristics of the femora between the voles (M. glareolus and M. arvalis separately) between the two biotopes. In addition, no statistically significant differences for any the measured variables of primary osteons’ vascular canals were observed. Correlation analysis in M. glareolus showed a strong positive relation between Cd and Ni (r = 0.52), Pb and bone weight (r = 0.53), Fe and bone weight (r = 0.52), and Fe and perimeter size of primary osteons’ vascular canals (r = 0.55). In common voles, a strong positive relation was found between Fe and Cu (r = 0.60) and between Fe and perimeter size of vascular canals of primary osteons (r = 0.55). Our results indicate that accumulation of some heavy metals is slightly increased in the femora of both species at Kolíňany.
Efficacy of Rodenticide Baits for the Control of Three Invasive Rodent Species in Hawaii by William C. Pitt; Laura C. Driscoll; Robert T. Sugihara (pp. 533-542).
We tested the efficacy and palatability of nine commercial rodenticide bait formulations on Polynesian rats (Rattus exulans), roof rats (R. rattus), and house mice (Mus musculus). Efficacy varied by rodenticide tested and rodent species. Generally, rodenticides were more effective against mice than for either of the rat species, and mice tended to consume more rodenticide bait than the laboratory chow alternative food. Efficacy was generally highest for the second-generation anticoagulants tested; however, this varied across products and one-first-generation rodenticide had similar effectiveness. Bait acceptance (palatability) also varied both by rodenticide and by rodent species. Acceptance was the lowest for the acute rodenticides. Bait acceptance appeared to substantially affect the efficacy of rodenticides; materials that were not well accepted produced lower mortality rates. Rodenticide products currently registered for use in Hawaii performed less effectively in this study than other available products not yet registered. Although markets for rodent control products for use on islands are limited, there are advantages to having additional products registered for island use in agriculture, conservation, and public health.
A Survey of Dietary Intake of Polychlorinated Dibenzo-p-dioxins, Polychlorinated Dibenzofurans, and Dioxin-like Coplanar Polychlorinated Biphenyls from Food During 2000–2002 in Osaka City, Japan by Tadashi Nakatani; Atsushi Yamamoto; Sumiko Ogaki (pp. 543-555).
Studies of the dietary intake of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like coplanar polychlorinated biphenyls (dioxin-like PCBs), collectively referred as dioxins, were conducted using the total diet study (TDS) method with food purchased in Osaka City, Japan during 2000–2002. The daily intake of dioxin-TEQ (toxic equivalent) from food per adult person was estimated respectively as 104.24 pg TEQ/person/day in 2000, 72.73 pg TEQ/person/day in 2001, and 87.28 pg TEQ/person/day in 2002, corresponding to 2.08, 1.45, and 1.74 pg TEQ/kg body weight (bw)/day for an adult weighing 50 kg. The highest contribution ratio to the total intake of dioxin-TEQ was from fish and shellfish (group 10) in each year, accounting for 77–92%. The next highest contributor was meat and eggs (groups 11-A and 11-B). An annual decrease of the intake of dioxin-TEQ was not observed clearly. Otherwise, the dietary intake of non-2,3,7,8-substituted PCDDs/PCDFs were estimated together. The intake of 1,3,6,8-TeCDD came mostly from intake of fish and shellfish (group 10), green vegetable (group 7), and the other vegetables, including mushrooms and seaweed (group 8). In addition, the intake of 1,3,6,8-TeCDF, which reportedly antagonizes 2,3,7,8-TeCDD-mediated aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) induction activities, was an insufficient amount to suppress 2,3,7,8-TeCDD-mediated activities. Furthermore, we discussed different TEQ compositions of PCDDs/PCDFs to dioxin-like PCBs from food intake and in human samples and inferred that the difference was caused by low bioaccumulation properties of 3,3′,4,4′,5-PeCB (PCB 126).
Human Exposure to PBDEs Via House Dust Ingestion in Guangzhou, South China by Laiguo Chen; Yumei Huang; Zhencheng Xu; Lijun Wen; Xiaochun Peng; Zhixiang Ye; Sukun Zhang; Xiang-Zhou Meng (pp. 556-564).
Numerous studies have demonstrated the important role played by indoor dust in human exposure to polybrominated diphenyl ethers (PBDEs), particularly in children, who spend most of their time indoors. Few data have been available for PBDEs in house dust in China. In this study, dust samples were collected randomly from 46 houses in Guangzhou, South China, for the first time to investigate levels and pattern profiles of PBDEs and to estimate human exposure to PBDEs for adults and toddlers (6 months to 2 years old). Using gas chromatography–mass spectrometry in selected ion monitoring mode, congeners—including BDE28, 47, 66, 85, 99, 100, 153, 154, 183, and 209—were determined. The results show that BDE209 is the predominant congener in house dust, comprising 90.7% to 99.8% (mean 97.4%) of the total concentration. Of ∑tri-hepta BDEs, BDE47, 99, and 183 were the most abundant congeners, with mean contributions of 23.3%, 25.2%, and 21.9%, respectively. The intake of ∑tri-hepta BDEs via dust ingestion was 0.16–3.82 ng/d for adults and 2.1–7.64 ng/d for toddlers, accounting for 0.65% to 13.6% and 18.6% to 45.5%, respectively, of the total (based on data in our previous work) (Chen et al. 2008). With respect to intake of BDE209, the values increased to 11 to 264 ng/d for adults and to 145 to 527 ng/d for toddlers. Risk assessment indicated that PBDEs may possibly affect the health of toddlers in Guangzhou, South China. Further studies are needed to investigate the bioavailability and metabolism of PBDEs in humans to improve risk evaluation.