Archives of Environmental Contamination and Toxicology (v.57, #2)
Combined Use of Bioindicators and Passive Samplers for the Assessment of River Water Contamination With Metals by Zrinka Dragun; Marijana Podrug; Biserka Raspor (211-220).
In autumn 2005, the site-specific variability of cytosolic metal and protein concentrations in gills of European chub from the Sava River could be mostly associated with gill mass variability. In spring 2006, the correlations of metals and proteins with gill mass were mainly nonsignificant, and their site-specific variability could be presumably associated with river water pollution. The spring cytosolic concentrations of Zn, Cu, and Mn did not differ significantly between the sites (medians: 8.37–11.34 μg ml−1, 68.2–86.2 ng ml−1, and 55.9–68.6 ng ml−1, respectively). Increased cytosolic Cd concentrations were obtained at Oborovo and Lukavec Posavski (median: 4.01 ng ml−1)—the sites influenced by pollution sources from two major urban areas—compared with the remaining sampling sites (median: 1.93 ng ml−1). Cytosolic Fe concentrations were almost two times higher at Jasenovac (median: 11.98 μg ml−1) compared with the concentrations at Sava-Zagreb (median: 6.72 μg ml−1). Labile Fe concentrations measured in river water with passive samplers indicated that cytosolic Fe concentrations in the spring possibly reflected water-borne Fe uptake. The spring cytosolic protein concentrations decreased from upstream (Otok Samoborski: 27.2 ± 5.6 mg ml−1) toward the downstream sites (Lukavec Posavski: 14.8 ± 2.8 mg ml−1), possibly because of the influence of organic pollution and water toxicity. The spring period seems to be a more appropriate season for the assessment of the river water pollution if chub gills are used as the target organ.
Oxidative Transformation of 17β-estradiol by MnO2 in Aqueous Solution by Liying Jiang; Cheng Huang; Jianmeng Chen; Xiao Chen (221-229).
17β-Estradiol (E2) is known as a natural endocrine disruptor and often found in municipal sewage. Batch experiments were conducted to assess the oxidative transformation of E2 in aqueous solutions by MnO2 and the probable degradation pathway. The results suggested that E2 could be degraded by MnO2, and the oxidation reaction deviated from pseudo-first-order kinetics due to the accumulation of reaction products in mineral surfaces and a gradual change of the surface site distribution toward less reactive sites. MnO2 dosage had a positive effect on oxidative transformation of E2, and both the initial reaction rate and the adsorption of E2 to oxide surfaces increased as the pH decreased. Two products, estrone and 2-hydroxyestradiol, were detected by gas chromatography coupled with mass spectrometry, and the probable degradation pathway was proposed. Results suggest that E2 can be oxidatively transformed by MnO2, which will provide some new insights into the interaction of estrogens with manganese oxides in natural soils and sediments.
Sequential Extractions and Isotope Analysis for Discriminating the Chemical Forms and Origins of Pb in Sediment from Liaodong Bay, China by Bing Xu; Zhaoyan Gu; Jingtai Han; Yanhui Zhang; Yongfu Chen; Yanwu Lu (230-238).
Sequential extraction integrated with isotope analysis was carried out on a sediment core from Liaodong Bay, northeast China, for characterizing Pb in various extraction phases and its possible sources. Results show that in all extracted fractions Pb concentrations increased abruptly in the top part of the sediments that deposited after 1980, but remained lower and rather constant before 1980. Consistent with the variation pattern of Pb concentration, the 206Pb/207Pb ratio displays a dramatic decrease around 1980. These findings strongly suggest serious Pb pollution since then. The Pb concentration and the isotopic ratios of 206Pb/207Pb and 208Pb/207Pb in the residual fraction show rather small changes through the entire core, and are similar to those of uncontaminated Chinese loess, possibly representing the characteristics of the regional geogenic background. The isotopic ratios of the sediments before 1980 varied in different extracted fractions with a linear pattern, from the residual at the highest toward the average signature of automobile exhausts and Pb-Zn deposits, implying a prominent two-end member mixing style of the Pb origin; one is the regional geologic background and the other is anthropogenic sources. The difference in isotopic ratios between the extractions might be indicative of varied proportions of the two sources. For sediments after 1980, however, the isotope ratios in nonresidual fractions are all relatively low and show little differentiation, which may suggest that polluted Pb dominates all the extracted fractions for the top part of the core.
Using Acetone as Solvent to Study Removal of Anthracene in Soil Inhibits Microbial Activity and Alters Nitrogen Dynamics by Edgar Vázquez Núñez; Viviana Rodríguez; Alejandro García Gaytán; Marco Luna-Guido; Liliana A. Betancur-Galvis; Rodolfo Marsch; Luc Dendooven (239-246).
Acetone is often used as a carrier to contaminate soil with polycyclic aromatic hydrocarbons (PAHs) and then to study the factors that control their removal. Acetone is an organic solvent that might affect soil processes. An alkaline saline (Texcoco soil) and an agricultural soil (Acolman soil) were amended with or without acetone, nitrogen + phosphorus (NP), and contaminated with anthracene at 520 mg/kg soil while emissions of CO2 and N2O and concentrations of NH4 +, NO2 – and NO3 – were monitored. The CO2 emission rate decreased greater than 10 times in the soils amended with acetone. Emission of N2O decreased 70 times in the Acolman soil amended with acetone and NP and 5 times in the Texcoco soil. The concentration of NH4 + decreased in the unamended Acolman and Texcoco soil but increased when acetone was added in the first and remained constant in the latter. Acetone inhibited the increase in the amount of NO3 – in the Acolman soil but not in the Texcoco soil. It was found that microbial activity as evidenced by the emission of CO2, nitrification, and production of N2O were inhibited by acetone. The amount of acetone used as solvent should thus be kept to a minimum, but it can be assumed that its effect on soil processes will be temporary, as microorganisms are known to repopulate soil quickly.
Occurrence and Fate of Organochlorinated Pesticides and PAH in Agricultural Soils from the Ebro River Basin by Alain Hildebrandt; Sílvia Lacorte; Damià Barceló (247-255).
This study was aimed to assess the presence and fate of 22 organochlorinated pesticides (OCHs) and their degradation products and 16 Environmental Protection Agency-priority polycyclic aromatic hydrocarbons (PAHs) in soils of the Ebro River basin (NE Spain) during a 3-year period. The study site is characterized by a long and active agricultural history where pesticides have largely been used. Soils were extracted using pressurized liquid extraction followed by gas chromatography–mass spectrometry. This procedure was optimized in terms of multiresidue analysis and effective cleanup and proved to have excellent analytical performance (recoveries ranging between 71% and 133%, standard deviation <14%, and a method detection limit from 0.19 to 7.38 μg/kg). Soils form the Ebro basin showed a prevalence of 4,4′-DDT and 4,4′-DDE, found in 53% and 88% of the soil samples between 0.13 and 58.17 μg/kg-dw (dry weight), respectively, indicating a slight decreasing trend of DDT within time. PAHs were detected in all soil samples at concentrations up to 465 μg/kg-dw, and the phenanthrene/anthracene (<10) and fluoranthene/pyrene (>1) ratios indicated combustion processes as the main source attributing to the burning of weeds and vegetable wastes after harvesting. No traces of any of the OCHs and PAHs were detected in groundwater, indicating that leaching for agricultural fields is not an important process of transport for these compounds. Overall, we propose the need to perform a monitoring program to evaluate the temporal tendencies and potential impact of pesticides and PAH in soils.
Necessity of Screening Water Chestnuts for Microcystins After Cyanobacterial Blooms Break Out by Fu-Gang Xiao; Xiao-Lian Zhao; Jian Tang; Xiao-Hong Gu; Jing-Ping Zhang; Wei-Min Niu (256-263).
Water chestnut is one of the most popular vegetables in Asian countries that grows in shallow water. Eighteen water chestnut samples were collected from Lake Tai and six samples were bought at markets in Wuxi, China, in October 2007. Extraction solution of water chestnut was cleaned up with a solid phase extraction column and immunoaffinity chromatography cartridges, then the microcystin (MC) level was detected by indirect competitive enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-mass spectrometry (LC-MS). The results of ELISA showed that there were six samples collected from Lake Tai which contained MCs; the highest level of total MCs was 7.02 ng/g. The results of LC-MS confirmed that MC-LR and MC-RR were present in five samples. The highest level of MC-LR was 1.02 ng/g and that of MC-RR was 4.44 ng/g. Heavy cyanobacterial blooms had occurred, and MCs were detected in water at the points in Lake Tai where MCs occurred in water chestnuts collected in 2007. MCs were not detected in the six samples bought at Wuxi markets. The results suggest that MCs can accumulate in water chestnuts, which is a potential hazard for human health.
Effects of a Realistic Mixture of Antibiotics on Resistant and Nonresistant Sewage Sludge Bacteria in Laboratory-Scale Treatment Plants by Ali Al-Ahmad; Annette Haiß; Jörg Unger; Andrea Brunswick-Tietze; Jürgen Wiethan; Klaus Kümmerer (264-273).
The detection of antibiotics and resistant bacteria in sewage treatment plants (STPs) has stimulated a discussion on the origin and selection of resistant bacteria during sewage treatment. Currently, there is little data available regarding the effects of realistic mixtures of antibiotics on the bacteria present in the aeration tanks of STPs. In this study we used four laboratory-scale sewage treatment plants (LSSTPs) to study the effects of antibiotics on bacteria during sewage treatment under standardized conditions. Two plants were fed with a mixture of antibiotics at two concentration levels based on the average annual input of antibiotics into German municipal STPs. The total operational period was 84 days. A multiresistant bacterium (Acinetobacter baumannii) was added twice to two of the plants. The fate of the multiresistant bacterium was monitored. The mix of antibiotics did not affect the purification efficiency. The presence of the antibiotics did not favour the multiresistant bacterium. No difference was detected between the test plant and the controls.
Natural DOM Affects Copper Speciation and Bioavailability to Bacteria and Ciliate by P. F. M. Nogueira; M. G. G. Melão; A. T. Lombardi; M. M. Nogueira (274-281).
This study aimed to investigate the influence of natural dissolved organic materials (DOM) on copper speciation (total dissolved, particulate, and free Cu2+ ions) and bioavailability during a two-level experimental microbial food chain. Bacteria were used as the first trophic level, and Paramecium caudatum (protozoan) as the second. The organisms were obtained from a freshwater reservoir and kept under controlled laboratory conditions. Three experimental treatments were performed: exposure of the organisms to copper in the absence of DOM, exposure to DOM in the absence of copper, and exposure to both copper and DOM. Freshwater medium containing natural DOM and copper at a total dissolved concentration of 1.8 × 10−6 mol L−1 was furnished to bacteria, which was further used as food to the protozoan. The results showed that after bacterial growth, DOM concentration decreased as quantified by total organic carbon determinations. At the same time, free Cu2+ ions concentration increased in the medium. A lower copper concentration was detected in both microorganisms in the presence of DOM. We conclude that natural DOM reduced copper accumulation in the organisms on the first and second trophic levels, thus reducing the entrance of copper into the aquatic microbial food chain.
Ability of Four Emergent Macrophytes to Remediate Permethrin in Mesocosm Experiments by M. T. Moore; R. Kröger; C. M. Cooper; S. Smith Jr. (282-288).
Increased focus is being placed on the ability of native vegetation to mitigate potential harmful effects of agricultural runoff, especially pyrethroid insecticides. Replicate 379 L Rubbermaid tubs (1.25 m [l] × 0.6 m [w] × 0.8 m [h]) were planted with individual species of cutgrass (Leersia oryzoides), cattails (Typha latifolia), bur-reed (Sparganium americanum), and powdery alligator-flag (Thalia dealbata), all common wetland macrophytes found in the Mississippi Delta, USA, agricultural region. Permethrin-enriched water (target concentration, 5 μg L−1) was pumped in at a 4-h hydraulic retention time at one end of the tub and discharged at the far end. Water samples were collected from discharge at 1-h intervals for 12 h and analyzed for permethrin concentrations. Permethrin removal rates were compared for the four different plant treatments and nonvegetated sediment-water controls. Results indicated that no particular single plant species was more effective at removing permethrin in water relative to unplanted controls. Overall mass reductions (from inflow to outflow) for cis-permethrin ranged from 67% ± 6% in T. latifolia to 71% ± 2% in L. oryzoides. The trans-permethrin overall mass reductions ranged from 76% ± 4% in S. americanum to 82% ± 2% in the unplanted control. Sediment and plant samples collected at the study conclusion indicated that 77%–95% of measured permethrin mass was associated with sediment for mesocosms planted with L. oryzoides, T. latifolia, and T. dealbata. Conversely, mesocosms planted with S. americanum had 83% of measured mass associated with the plant material. Specific plant-pesticide retention studies can lead to improved planning for best management practices and remediation techniques such as constructed wetlands and vegetated agricultural drainage ditches.
Carryover of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) from Soil to Plants by T. Stahl; J. Heyn; H. Thiele; J. Hüther; K. Failing; S. Georgii; H. Brunn (289-298).
Within the scope of a joint project to study soil-to-plant carryover of polyfluorinated compounds (PFCs), five cultivated plants (spring wheat, oats, potatoes, maize, and perennial ryegrass) were sown or planted in Mitscherlich pots. Six variants per species were used, each with a different concentration level of PFOA and PFOS (from 0.25 to 50 mg/kg as aqueous solution) to detect possible concentration dependence in the transfer of these two PFCs from soil to plant. PFOA and PFOS were detected by liquid chromatography-tandem mass spectrometry after appropriate sample preparation (partial drying, mincing, homogenizing, extraction). Since PFOA and PFOS presently represent the most widely studied PFCs, they are classified as “leading compounds.” The results show that concentrations of PFOA/PFOS in the plants vary greatly, depending on the concentrations applied to the soil. PFOA values were higher than PFOS values in all plants except potatoes, in which these differences could be quite substantial. From the results presented here it can be seen that uptake and storage are much more intensive in the vegetative portion of the plant than relocation in the storage organs. This is particularly evident from the the comparison of concentrations found in the grain and ear and those in the straw or rest of the plant in spring wheat, oats, and maize. Transfer from “soil to crops” provides a possible explanation for the presence of PFCs in foodstuffs and in human body fluids such as blood, plasma, serum, or breast milk. The aim of the present study was to determine whether a statistically significant, concentration-dependent carryover of PFOA and PFOS in crop plants can take place, which would provide a potential entrance point for these substances into the food chain.
Characterization of Cadmium Uptake and Translocation in a Cadmium-Sensitive Mutant of Rice (Oryza sativa L. ssp. japonica) by J. Y. He; Y. F. Ren; F. J. Wang; X. B. Pan; C. Zhu; D. A. Jiang (299-306).
To understand the physiological mechanism that confers Cd sensitivity/tolerance, Cd uptake and translocation by Cd-sensitive mutant and wild-type rice seedlings were characterized using radioactive tracer. Time-dependent Cd accumulation during 210 min was 1.8-fold higher in roots of the mutant than of wild-type rice. The kinetics of Cd uptake showed that two processes were involved: a first, fast, probably passive process and a second, slower, possibly physiological process. After 96 h, more Cd was translocated to the shoot of mutant compared with wild-type rice. Low temperature (2°C), carbonyl cyanide m-chlorophenylhydrazone, and dicyclohexylcarbodiimide inhibited Cd accumulation to a greater extent in mutant than wild-type rice, suggesting that metabolism plays a more important role in Cd uptake for the rice mutant. Cd uptake into the symplasm is linked to Ca2+ transport, as revealed by the inhibition of Cd accumulation by La and high Ca by equal percentages in both mutant and wild-type rice. Cd uptake and root-to-shoot translocation in the mutant were inhibited more markedly by Zn and Mn than in wild-type rice. This indicates that transport sites other than entry into the root symplasm are also stimulated in the mutant. The results suggest that enhanced absorption into the root and further accumulation in the shoot is one of the mechanisms involved in Cd accumulation and sensitivity, and the difference in Cd uptake and root-to-shoot translocation between mutant and wild-type rice may be mediated partly by energy supply and transporters for Zn and Mn.
Textile Effluents Induce Biomarkers of Acute Toxicity, Oxidative Stress, and Genotoxicity by Valdelúcia M. A. S. Grinevicius; Reginaldo Geremias; Rogério Laus; Karina F. Bettega; Mauro C. M. Laranjeiras; Valfredo T. Fávere; Danilo Wilhelm Filho; Rozangela C. Pedrosa (307-314).
The present work consists of a comparative evaluation of the toxicity of a nonremediated textile effluent (NRTE) with an effluent remediated by a pulverized chitosan system (RCTS) or by a conventional effluent process (remediated biologic and physico-chemical effluent [RBPC]). Acute toxicity assays, oxidative stress biomarkers, physico-chemical parameters, and genotoxicity indices were analyzed to achieve the toxicity of all effluents. After RCTS treatment, approximately 80% of dyes were removed, together with a significant decreased of the metal content, compared with a relatively increase in metal content after RBPC treatment. RBPC and RCTS treatments did not cause acute toxicity to Vibrio fischeri and Artemia sp., whereas RBPC caused acute toxicity to Daphnia magna but RCTS did not. Compared with NRTE, chitosan remediation decreased oxidative stress biomarkers, such as the contents of lipoperoxidation (measured as thiobarbituric acid-reactive substances [TBARS], 29.9%) and the reduced form of glutathione (GSH; 73.5%) levels in D. rerio, whereas animals exposed to RBPC showed enhanced TBARS (57.2%) and decreased GSH concentrations (56.4%). RCTS and RBPC remediation elicited catalase activity induction (161.8% and 127.3%, respectively) compared with NRTE. Accordingly, DNA fragmentation and micronucleus frequency in D. rerio decreased after remediation with RBPC or RCTS compared with NRTE, but RCTS treatment was more effective than RBPC in decreasing genotoxicity (90.5% and 73.8% decrease in DNA fragmentation and 67.8% and 50.4% decrease in micronucleus frequency, respectively). The results indicate that chitosan adsorption system is a useful tool for textile effluent remediation compared with the conventional remediation by biologic and physico-chemical processes.
Toxicity of Sediment Cores Collected from the Ashtabula River in Northeastern Ohio, USA, to the Amphipod Hyalella azteca by Christopher G. Ingersoll; Nile E. Kemble; James L. Kunz; William G. Brumbaugh; Donald D. MacDonald; Dawn Smorong (315-329).
This study was conducted to support a Natural Resource Damage Assessment and Restoration project associated with the Ashtabula River in Ohio. The objective of the study was to evaluate the chemistry and toxicity of 50 sediment samples obtained from five cores collected from the Ashtabula River (10 samples/core, with each 10-cm-diameter core collected to a total depth of about 150 cm). Effects of chemicals of potential concern (COPCs) measured in the sediment samples were evaluated by measuring whole-sediment chemistry and whole-sediment toxicity in the sediment samples (including polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], organochlorine pesticides, and metals). Effects on the amphipod Hyalella azteca at the end of a 28-day sediment toxicity test were determined by comparing survival or length of amphipods in individual sediment samples in the cores to the range of responses of amphipods exposed to selected reference sediments that were also collected from the cores. Mean survival or length of amphipods was below the lower limit of the reference envelope in 56% of the sediment samples. Concentrations of total PCBs alone in some samples or concentrations of total PAHs alone in other samples were likely high enough to have caused the reduced survival or length of amphipods (i.e., concentrations of PAHs or PCBs exceeded mechanistically based and empirically based sediment quality guidelines). While elevated concentrations of ammonia in pore water may have contributed to the reduced length of amphipods, it is unlikely that the reduced length was caused solely by elevated ammonia (i.e., concentrations of ammonia were not significantly correlated with the concentrations of PCBs or PAHs and concentrations of ammonia were elevated both in the reference sediments and in the test sediments). Results of this study show that PAHs, PCBs, and ammonia are the primary COPCs that are likely causing or substantially contributing to the toxicity to sediment-dwelling organisms.
Effects of Environmental Contaminants on Hemoglobin Gene Expression in Daphnia magna: A Potential Biomarker for Freshwater Quality Monitoring by Mi-Hee Ha; Jinhee Choi (330-337).
Daphnia hemoglobin (Hb) is one of the widely investigated invertebrate respiratory pigment. In this study, alteration of Daphnia magna Hb was evaluated in terms of its gene expression, using four D. magna Hb open reading frames (ORFs), by exposure of various chemicals, such as nonylphenol (NP), bisphenol A (BPA), benzo[a]pyrene (B[a]P), chloropyriphos (CP), paraquat dichloride (PQ), and lead nitrate (Pb), under laboratory conditions. A Daphnia reproduction test was also conducted to test the ecotoxicological relevance of chemical-induced Daphnia Hb gene expression. Daphnia Hb gene expression increased by most of tested chemicals. Nonylphenol induced all four Hb ORFs, and an increase in D. magna hemoglobin 2 (dmhb2), dmhb3, and dmhb4 gene expression was exposure concentration dependent. Although BPA and B[a]P also induced most of the Hb genes, the degree of increase was less than two-fold compared to the control. For CP and Pb exposure, an increase in dmhb2 and dmhb4 gene expression was the most significant among the four Daphnia Hb ORFs. Each ORF might exhibit different sensitivities to chemical stress; of the four ORFs studied, an increase in dmhb2 and dmhb4 gene expression was the most significant. It seems clear that Daphnia Hb has a considerable potential as a biomarker for freshwater toxicity monitoring, as an increase in Hb gene expression seems to be correlated with a decrease in reproduction in this animal. The results suggest that Daphnia Hb could give useful information to diagnose general health conditions in a freshwater ecosystem. Considering the potential of D. magna as a biomonitoring species and the physiological particularities of its respiratory pigments, Daphnia Hb could be developed as a biomarker for ecotoxicity monitoring.
Toxicokinetics of Waterborne Trivalent Arsenic in the Freshwater Bivalve Corbicula fluminea by Pedro M. Costa; Hugo M. Santos; Isabel Peres; Maria H. Costa; Sheila Alves; José Luís Capelo-Martinez; Mário S. Diniz (338-347).
Arsenite (AsIII) uptake and elimination kinetics were studied in a freshwater bivalve, Corbicula fluminea, exposed to several nominal concentrations of AsIII (0, 100, 300, 500, and 1000 μg L−1) in a static 28-day assay, followed by a depuration stage of 14 days. At the end of each sampling time (days 0, 7, 28, and 42) whole-body portions were surveyed for total As concentrations and, complimentarily, surveyed for whole-body metallothionein (MT) induction to assess its role as a defense mechanism against exposure to AsIII. Histochemical evaluation of the digestive gland was performed to verify As deposition and elimination in the tissue. Results show a significant increase in whole-body total As after 28 days of exposure for all treatments, followed by a decrease at the end of the depuration phase. Biodynamic kinetic models for As uptake and elimination were obtained from bioaccumulation data during the exposure phase, for all As treatments, by estimating uptake and elimination rate constants. Bioconcentration factors (BCFs) were estimated by the ratio of these constants. Results revealed that exposure to higher concentrations of AsIII causes a decrease in BCFs, suggesting that C. fluminea triggers effective regulatory mechanisms when exposed to higher concentrations of the metalloid. Significant induction of MT was detected during the exposure phase, followed by a decrease in MT concentration to control levels after depuration for all treatments. No significant differences in MT concentrations were observed between treatments. This finding may confirm the role of MT as part of the As regulation process, but its independence relative to concentrations of AsIII in water suggests that MT induction is not dose dependent. The histochemical evaluation provided clear evidence that As was effectively accumulated in the digestive gland during exposure and eliminated during depuration. The present work demonstrated that C. fluminea is capable of regulating As, even at exposures as high as 1000 μg L−1 of waterborne AsIII.
Organic Contaminants in the Marine Environment of Manila Bay, Philippines by Fernando P. Carvalho; Jean-Pierre Villeneuve; Chantal Cattini; Inmaculada Tolosa; Cristina M. Bajet; MariaFe Navarro-Calingacion (348-358).
Organochlorine pesticides (OCs) and polychlorobiphenyls (PCBs) were determined in sediments and oysters’ soft tissues (Cassostrea gigas) collected in selected sites of Manila Bay. Overall, the concentration levels were very low. In sediments, PCBs were the compounds present in higher concentrations, with Σ13PCB congeners averaging 0.69 ± 0.46 ng/g (dry weight), followed by ΣDDT averaging 0.53 ± 0.28 ng/g and Σchlordane with 0.26 ± 0.28 ng/g. Concentrations measured in oysters averaged 20 ± 17 ng/g (dry weight) for Σ13PCB and were higher than ΣDDT, with 9.5 ± 2.4 ng/g, and Σchlordane, with 3.8 ± 3.1 ng/g. No dissolved residues of polar compounds, such as herbicides, and organophosphorous and organochlorine pesticides were found in the bay water. In general, results showed that concentrations of organochlorine pesticide residues, such as DDT, hexachlorocyclohexane, chlordane, lindane, endosulfan, and heptachlor in sediments and oysters were low in comparison with other coastal areas in Asia, although PCB concentrations in oysters were relatively high in some zones of Manila Bay and indicative of loose control of industrial chemical waste discharges into the bay. Nevertheless, current concentrations of persistent organochlorine contaminants in sediments were under threshold effect levels (TELs) and chronic toxic effects are, thus, unlikely to generate impairment of marine biota in Manila Bay.
Accumulation of Lead, Chromium, and Cadmium in Muscle of capitán (Eremophilus mutisii), a Catfish from the Bogota River Basin by Adriana Rodríguez Forero; Jaime Fernando González Mantilla; Roger Suárez Martínez (359-365).
Heavy metal accumulation of lead (Pb), chromium (Cr), and cadmium (Cd) in the muscle of the catfish Eremophilus mutisii was studied in 47 specimens, captured by anglers in the Bogotá River at two sampling sites (Chocontá and Suesca) during May–October 2005. Water samples were processed for physicochemical and metal analyses. Metal accumulation in muscle (wet weight) of specimens at Chocontá and Suesca showed high levels of Pb (3.4 and 3.1 ppm, respectively), Cr (1.8 and 2.1 ppm, respectively), and Cd (0.35 and 0.48, respectively). Metal levels in waters (ppm) indicated that average Pb (0.028 Chocontá, 0.029 Suesca), Fe (0.462 Chocontá, 1.1 Suesca), and Cr (0.113 Chocontá) were above the maximum levels (MCLs) allowed in drinking waters. No extreme average values were found for pH, nitrites, alkalinity, and hardness in the waters. This study showed the importance of benthic and nonmigratory species like the capitán to evaluate the effects of heavy metals pollution. Further public health implications could be derived in the region where this investigation took place due to consumption of capitán by people in the area.
Physiological Stress in Native Southern Brook Trout During Episodic Stream Acidification in the Great Smoky Mountains National Park by Keil J. Neff; John S. Schwartz; Theodore B. Henry; R. Bruce Robinson; Stephen E. Moore; Matt A. Kulp (366-376).
Episodic stream acidification from atmospheric deposition is suspected to detrimentally impact native southern brook trout (Salvelinus fontinalis) in Great Smoky Mountains National Park (GRSM) headwater streams. To test the hypothesis that episodes of stream acidification cause physiological distress to native trout, caged fish at three sites were exposed to acid episodes during in situ bioassays conducted in June 2006 and March 2007. Stream pH decreased (>0.7 pH units) and total dissolved aluminum (AlTD) increased (>175 μg/L) at all three sites during acid episodes in both bioassays. Whole-body sodium concentrations were significantly reduced (10–20%) following the acid episodes, when preceding 24-h mean pH values of 4.88, 5.09, and 4.87 and corresponding 24-h time-weighted average AlTD concentrations of 210, 202, and 202 μg/L were observed. Lower whole-body sodium concentrations were correlated with elevated H+ and AlTD concentrations. Loss of sodium ions in native southern brook trout was consistent with physiological distress resulting from acid exposure reported in salmonids in other investigations. Further research is necessary to conclude whether acid episodes are responsible for extirpation of brook trout from headwater streams in the GRSM.
Biochemical Responses and Accumulation Properties of Long-Chain Perfluorinated Compounds (PFOS/PFDA/PFOA) in Juvenile Chickens (Gallus gallus) by Leo W. Y. Yeung; Eva I. H. Loi; Vicky Y. Y. Wong; Keerthi S. Guruge; Noriko Yamanaka; Nobuhiko Tanimura; Jun Hasegawa; Nobuyoshi Yamashita; Shigeru Miyazaki; Paul K. S. Lam (377-386).
One-day-old male chickens were exposed via oral gavage to mixtures of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorodecanoate (PFDA) at either a low dose (0.1 mg/kg body weight [b.w.]) or a high dose (1.0 mg/kg b.w.), or a saline/ethanol vehicle control, three times a week for 3 weeks. After 3 weeks of exposure, half of the chicks were sacrificed and the other half were allowed to depurate for a further 3 weeks. No dose-dependent statistically significant differences in body/organ weights were observed among treatment and control groups after 3 weeks of exposure or after three 3 of depuration. Neither 15 histological nor 14 measured plasma biochemical parameters were significantly different in chicks from the exposed groups and vehicle controls. PFOS, PFDA, and PFOA concentrations in blood/liver/kidney samples were measured throughout the exposure and depuration periods at different time intervals. PFOS and PFDA accumulated at much higher concentrations than PFOA during the experimental periods. Interestingly, PFOS and PFDA accumulation patterns in the blood were similar during the exposure and depuration periods. The half-lives for each PFC at the 0.1 and 1.0 mg/kg doses were, respectively, approximately 15 and 17 days for PFOS, 11 and 16 days for PFDA, and 3.9 and 3.9 days for PFOA. PFDA accumulation in organs was greater than or similar to that of PFOS: the liver was the main target during exposure and the blood was the main reservoir during depuration. These results indicate that exposure to a 1.0-mg mixture of PFOS/PFDA/PFOA/kg b.w. has no adverse effect on juvenile chickens.
Environmental Contaminants in White-Winged Doves (Zenaida asiatica asiatica) from the Lower Rio Grande Valley of Texas, USA by Timothy B. Fredricks; Alan M. Fedynich; Steve Benn; Larisa Ford (387-396).
Our study determined if white-winged doves (WWDs; Zenaida asiatica asiatica) breeding in locations where environmentally persistent contaminants occur in the Lower Rio Grande Valley of Texas have levels of contaminants that can hinder reproduction. During summer 2003, 70 (32 males, 38 females) adult WWDs were collected from 8 at-risk sites. Liver tissues were analyzed for ten major and trace elements and muscle tissues were analyzed for 20 organochlorine compounds, 21 polychlorinated biphenyl congeners, and toxaphene. Samples were compared to ten (five male, five female) captive-raised control WWDs. Arsenic, chromium, and lead were not detected or were below the detection limit, whereas copper, zinc, selenium, mercury, nickel, cadmium, and silver were detected in 70 (100%), 70 (100%), 52 (74%), 21 (30%), 4 (6%), 1 (1%), and 1 (1%) WWDs, respectively. None of the detected elements had significant sampling site, bird gender, or Site × Gender interactions, and each occurred at background levels. Toxaphene and polychlorinated biphenyls were not detected, whereas DDE, dieldrin, γ-BHC, and chlordane were detected in 13 (19%), 5 (7%), 2 (3%), and 1 (1%) field-collected WWDs, respectively, but all concentrations occurred at background levels. Concentrations of elements and compounds in field-collected WWDs did not significantly differ from those of the controls. Correlations between leukocyte counts and detectable contaminants generally indicated no correlation between each percentage of leukocyte type present and levels of selenium, copper, zinc, mercury, or DDE detected. One sample that had 0.072 μg/g dieldrin exhibited a low lymphocyte percentage (66%) out of only five samples. Comparisons could not be made with γ-BHC, chlordane, or the other elements that had a low number of samples with detectable levels. Overall, concentrations of elements and organochlorines found in WWDs were below levels known to impair reproduction and survival in birds.
Levels and Profiles of Polychlorinated Dibenzo-p-Dioxins, Polychlorinated Dibenzofurans, and Polychlorinated Biphenyls in Feedstuffs and Milk From Farms in the Vicinity of Incineration Plants in Tuscany, Italy by Anna Maria Ingelido; Annalisa Abballe; Alessandro di Domenico; Igor Fochi; Nicola Iacovella; Alberto Saragosa; Maurizio Spagnesi; Silvia Valentini; Elena De Felip (397-404).
Levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorobiphenyls (PCBs) were determined in samples of bovine and ovine milk collected in farms located in the province of Grosseto, Tuscany, in the vicinity of two incineration plants as well as in farms located in areas with presumable background levels of contamination. Samples of feedstuffs of local origin used in the investigated farms were also collected and analysed. The cumulative levels of PCDDs, PCDFs, and dioxin-like PCBs (DL-PCBs) in feedstuffs ranged from 0.25 to 0.61 pg WHO-TE/g fresh weight (fw) in the farms under impact from incinerator emissions and from 0.21 to 0.34 pg WHO-TE/g fw in the control area farms. The sums of the six non–dioxin-like indicator PCB (NDL-PCB) congeners were 0.13 to 9.3 ng/g fw and 1.2 to 1.9 ng/g fw, respectively. In milk samples, the levels detected were 0.71 to 2.9 pg WHO-TE/g fat and 0.52 to 0.59 pg WHO-TE/g fat in farms under impact from the incinerators and in the control area farms, respectively. The corresponding sums of the six indicator PCB congeners were 1.4 to 8.2 ng/g fat and 0.90 to 1.6 ng/g fat. In all samples, contamination levels were below the limits set by the European Community (EC; Commission Directive 2006/13/EC and Commission Regulation 1881/2006/EC.) No relevant differences were found between samples collected in potentially exposed areas and control areas for total toxic equivalents and cumulative analytic levels of PCDDs, PCDFs, DL-PCBs, and NDL-PCBs (p > 0.05, Mann-Whitney U test). Observed levels were in agreement with those found in other countries in areas with background levels of exposure. Congener levels and profiles of PCDDs, PCDFs, and PCBs in feedstuffs and milk samples that were compared describe congener-specific transfer behavior.
Seawater and Shellfish (Geukensia demissa) Quality Along the Western Coast of Assateague Island National Seashore, Maryland: An Area Impacted by Feral Horses and Agricultural Runoff by Mary S. Lambert; Gulnihal Ozbay; Gary P. Richards (405-415).
We evaluated the quality of seawater and ribbed mussels (Gukensia demissa) at six sites along the West Coast of Assateague Island National Seashore (ASIS), a barrier island popular with tourists and fishermen. Parameters evaluated were summertime temperature, pH, salinity, dissolved oxygen, total phosphorus, total ammonia nitrogen, and nitrite levels for seawater and total heterotrophic plate counts and total Vibrionaceae levels for the ribbed mussels. Approximately 150 feral horses (Equus caballus) are located on ASIS and, combined with agricultural runoff from animals and croplands, local wildlife, and anthropogenic inputs, contribute to nutrient loads affecting water and shellfish quality. The average monthly dissolved oxygen for June was 2.65 mg L−1, below the minimum acceptable threshold of 3.0 mg L−1. Along Chincoteague Bay, total phosphorus generally exceeded the maximum level of 0.037 mg L−1, as set by the Maryland Coastal Bays Program management objective for seagrasses, with a high of 1.92 mg L−1 in June, some 50-fold higher than the recommended threshold. Total ammonia nitrogen approached levels harmful to fish, with a maximum recorded value of 0.093 mg L−1. Levels of total heterotrophic bacteria spiked to 9.5 × 106 cells g−1 of mussel tissue in August in Sinepuxent Bay, leading to mussels which exceeded acceptable standards for edible bivalves by 19-fold. An average of 76% of the bacterial isolates were in the Vibrionaceae family. Together, these data suggest poor stewardship of our coastal environment and the need for new intervention strategies to reduce chemical and biological contamination of our marine resources.
Hepatic P450 Enzyme Activity, Tissue Morphology and Histology of Mink (Mustela vison) Exposed to Polychlorinated Dibenzofurans by Jeremy N. Moore; John L. Newsted; Markus Hecker; Matthew J. Zwiernik; Scott D. Fitzgerald; Denise P. Kay; Xiaowei Zhang; Eric B. Higley; Lesa L. Aylward; Kerrie J. Beckett; Robert A. Budinsky; Steven J. Bursian; John P. Giesy (416-425).
Dose- and time-dependent effects of environmentally relevant concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQ) of 2,3,7,8-tetrachlorodibenzofuran (TCDF), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or a mixture of these two congeners on hepatic P450 enzyme activity and tissue morphology, including jaw histology, of adult ranch mink were determined under controlled conditions. Adult female ranch mink were fed either TCDF (0.98, 3.8, or 20 ng TEQTCDF/kg bw/day) or PeCDF (0.62, 2.2, or 9.5 ng TEQPeCDF/kg bw/day), or a mixture of TCDF and PeCDF (4.1 ng TEQTCDF/kg bw/day and 2.8 ng TEQPeCDF/kg bw/day, respectively) for 180 days. Doses used in this study were approximately eight times greater than those reported in a parallel field study. Activities of the cytochrome P450 1A enzymes, ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-deethylase (MROD) were significantly greater in livers of mink exposed to TCDF, PeCDF, and a mixture of the two congeners; however, there were no significant histological or morphological effects observed. It was determined that EROD and MROD activity can be used as sensitive biomarkers of exposure to PeCDF and TCDF in adult female mink; however, under the conditions of this study, the response of EROD/MROD induction occurred at doses that were less than those required to cause histological or morphological changes.