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Archives of Environmental Contamination and Toxicology (v.59, #4)
Monitoring Temporal Trends in Environmental Levels of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans: Results From a 10-Year Surveillance Program of a Hazardous Waste Incinerator by Lolita Vilavert; Martí Nadal; Montse Mari; Marta Schuhmacher; José L. Domingo (pp. 521-531).
The only hazardous waste incinerator (HWI) in Spain has been operating in Constantí (Tarragona County, Catalonia) since 1999. Before its construction, a surveillance program was initiated to monitor the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the neighborhood of the facility. In 2008, 40 soil and 40 vegetation samples were collected and PCDD/F levels determined. The median PCDD/F concentration in soil was 0.49 ng international toxic equivalents (I-TEQ)/kg. Although it meant a nonsignificant decrease of 44% with respect to the preoperational survey, important fluctuations of the levels of PCDD/Fs through time were found in some specific sites. Therefore, a new survey was performed 1 year later (2009) by deleting those sampling sites with inconstant values, which mostly coincided with urban zones. In 2009, the median level of PCDD/Fs in soils was found to be 0.42 ng I-TEQ/kg. In contrast, median PCDD/F levels in vegetation were 1.11 ng I-TEQ/kg, a significant increase compared with previous surveys (range of the median 0.21–0.25 ng I-TEQ/kg). However, this increase was uniformly observed in the entire sampling area, suggesting that lack of rainfall was a key parameter for decreasing plant dilution and wash-up of pollutants on vegetation. This indicates that in surveillance programs, information must be obtained from different sources because the use of a single compartment may yield significant misinterpretation when evaluating temporal trends of environmental pollutants. Human health risks derived from exposure to PCDD/Fs were also assessed for the local population. The results indicated that current concentrations of these contaminants do not pose any additional carcinogenic or noncarcinogenic risk for those people living near the HWI.
Mixture Toxicity of SN2-Reactive Soft Electrophiles: 1. Evaluation of Mixtures Containing α-Halogenated Acetonitriles by D. A. Dawson; J. Jeyaratnam; T. Mooneyham; G. Pöch; T. W. Schultz (pp. 532-541).
The concept of multiple modes of toxic action denotes that an individual chemical can induce two or more toxic effects within the same series of concentrations, for example, reactive toxicity and narcosis. It appears that such toxicity confounds the ability to develop precise predictions of mixture toxicity and makes it more difficult to clearly link a dose-additive combined effect to agents in the mixture having a single common mechanism of toxic action. This initial study of a three-part series begins to examine this issue in greater detail by testing three α-halogenated acetonitriles: (1) in sham combinations, (2) in true combinations, and (3) with a nonreactive nonpolar narcotic. Iodo-, bromo-, and chloro-derivatives of acetonitrile were selected for testing based on their electro(nucleo)philic reactivity, via the SN2 mechanism, and their time-dependent toxicity individually. Reactivity of each agent was assessed in tests with the model nucleophile glutathione (GSH). Each acetonitrile was reactive with GSH, but the nonpolar narcotic 3-methyl-2-butanone was not. In addition, toxicity of the agents alone and in mixtures was assessed using the Microtox® acute toxicity test at three time points: 15, 30, and 45 min of exposure. Each of the three agents alone had time-dependent toxicity values of about 100%, making it likely that most of the toxicity of these agents, at these times, was due to reactivity. In contrast, the nonpolar narcotic agent lacked time-dependent toxicity. In mixture testing, sham combinations of each acetonitrile showed a combined effect consistent with predicted effects for dose-addition at each time point, as did the sham combination of the nonpolar narcotic. Mixture toxicity results for true acetonitrile combinations were also consistent with dose-addition, but the acetonitrile–nonpolar narcotic combinations were generally not consistent with either the dose-addition or independence models of combined effect. Based on current understanding of mixture toxicity, these results were expected and provide a foundation for the second and third studies in the series.
Ambient Air Levels and Trends of Polychlorinated Biphenyls at Four Different Sites by S. Sıddık Cindoruk; Yücel Tasdemir (pp. 542-554).
In this study, samples were collected in order to determine atmospheric levels of polychlorinated biphenyls (PCBs) in four different sites by using a high-volume air sampler (HVAS). Eighty-three congeners of gas and particle- phase PCBs were investigated in air samples. The total (gas + particle) concentrations for Mudanya (coastal), Butal (traffic/urban), the Uludag University Campus (semirural), and Yavuz Selim (residential) were determined as 570, 394, 412, and 316 pg/m3, respectively. These levels coincide with the values reported for the sites having similar characteristics. In terms of homolog groups, 3-chlorinated biphenyls (3-CBs) and 4-CBs constituted at least 47% of the total PCB concentration. PCBs in all sites were determined mostly in the gas phase, with a percentage from 85 to 95%. Obtained atmospheric PCB data were correlated with meteorological parameters and a significant relationship was obtained between coastal and semirural sites (p < 0.05). With the movements of air transportation and wind rose possible data sources of PCBs were enlightened. Partitioning of gas/particle was examined with available models; significant relationships were determined for coastal and semirural sites especially.
Transplantation of Microbenthic Algal Assemblages to Assess Structural and Functional Recovery After Diuron Exposure by Ursula Dorigo; Annette Bérard; Agnès Bouchez; Frédéric Rimet; Bernard Montuelle (pp. 555-563).
The potential of microbenthic algal assemblages to recover after diuron exposure was investigated. Microbenthic algal assemblages (periphyton) were grown on glass slides in correspondence to a diuron-polluted and a diuron-free sampling site of a river. After 5 weeks of colonization, the impacted periphyton was transferred by translocating the colonized glass slides to the unpolluted site. To monitor the changes in functional and structural parameters and to assess recovery, both the transferred and the local reference periphyton were sampled at the day of transfer (t0) and 1, 3, and 5 weeks after the transfer (t1, t3, t5). Structural transitions of eukaryotic communities were characterized by denaturing gradient gel electrophoresis (DGGE) and functional ones were characterized by short-term incubation toxicity tests with diuron. As shown by Bray–Curtis similarity values based on DGGE band patterns, almost total structural recovery of the transferred periphyton took place 5 weeks after transfer. For the transferred periphyton, previous diuron exposure at the contaminated site induced the development of diuron tolerance, which decreased after 1 week and became very similar to the tolerance of the nonimpacted community after 5 weeks. It is concluded that 5-week-old eukaryotic periphyton communities are capable of restoring their structural and functional attributes after 5 weeks within a noncontaminated environment.
Effects of Soil Polycyclic Musk and Cadmium on Pollutant Uptake and Biochemical Responses of Wheat (Triticum aestivum) by Cui-hong Chen; Qi-xing Zhou; Zhang Cai; Ying-ying Wang (pp. 564-573).
The single and joint toxicological effects of AHTN and cadmium (Cd) on early developmental stages of wheat, including AHTN and Cd uptake, chlorophyll (CHL), malondialdehyde (MDA), superoxide dismutase (SOD), and peroxidase (POD) contents in the seedlings, were investigated. Uptake of AHTN or Cd by seedlings increased with an increase in the concentrations of AHTN and Cd in soil. The presence of Cd inhibited the uptake of AHTN in wheat seedlings, while the low concentration of AHTN could induce the uptake of Cd. The biosynthesis of CHL was significantly inhibited by single AHTN and joint stress with AHTN and Cd. The MDA contents in wheat leaves and roots were significantly affected by single and joint stress with AHTN and Cd. SOD and POD activities in leaves was significantly induced by AHTN and Cd. However, the effect of AHTN and Cd on SOD and POD activities in roots was insignificant. This might indicate that wheat leaves were more sensitive to the binary mixture than wheat roots.
Effect of Three Insecticides and Two Herbicides on Rice (Oryza sativa) Seedling Germination and Growth by M. T. Moore; R. Kröger (pp. 574-581).
Rice (Oryza sativa L.) is one of the most important food crops worldwide. However, it is also a valuable tool in assessing toxicity of organic and inorganic compounds. For more than 20 years, it has been an approved species for standardized phytotoxicity experiments. The objective of this study is to determine germination and radicle (root) and coleoptile (shoot) growth of rice seeds exposed to three insecticides and two herbicides, commonly used in the agricultural production landscape. Although no germination effects of pesticide exposure were observed, significant growth effects were noted between pesticide treatments. Coleoptile growth was significantly (p ≤ 0.05) lowered in metolachlor/atrazine mixture, diazinon, and lambda-cyhalothrin exposures when compared with controls. Radicles of fipronil-exposed seeds were significantly larger (p ≤ 0.05) when compared with controls. This research contributes to the phytotoxicity assessment database, in addition to laying the foundation for the use of rice as a phytoremediation tool for agricultural pesticide runoff.
Presence and Distribution of Persistent Toxic Substances in Sediments and Marine Organisms of Potter Cove, Antarctica by Antonio Curtosi; Emilien Pelletier; Cristian Vodopivez; Richard St Louis; Walter Patricio Mac Cormack (pp. 582-592).
Levels of butyltin compounds, polychlorinated biphenyls, and heavy metals were analyzed in marine sediments and organisms (Notothenia coriiceps, Laternula elliptica, and Nacella concinna), each of which has a different feeding strategy, in Potter Cove, Antarctica. PCBs were lower than detection limits in all samples. Only butyltin compounds were detected in a restricted area near the scientific station. Chromium, copper, magnesium, lead (Pb), and zinc had similar behavior in the cove, probably because they are regulated by similar process and conditions. However, Pb levels in some sites of the cove seem to be related to human activities in the area. Cadmium levels were relatively low, with the highest values found close to the shoreline, which is probably influenced by seasonal streams draining waters from Potter Peninsula. Results showed that despite the fact that Jubany Station has been operating for >50 years, surface sediment and biota from Potter Cove do not exhibit levels of pollutants representing environmental concern.
Trace Element Accumulation in Bivalve Mussels Anodonta woodiana from Taihu Lake, China by Hongbo Liu; Jian Yang; Juli Gan (pp. 593-601).
Data are presented for 13 trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, and Pb) in 38 bivalve mussels Anodonta woodiana from four separate sites (Huzhou, Dapu, Sansandao, and Manshan) around the Taihu Lake of China. All elemental concentrations generally ranked in decreasing order, Mn > Fe > Zn > As ≈ Cu ≈ Cd ≈ Se > Pb > Mo ≈ Ag, except that Cr, Co, and Ni were not detected. Anodonta woodiana was able to bioaccumulate essential Mn and toxic Cd to the extremely high level of 19,240 and 53 mg/kg dry weight, respectively. Geographical differences in the concentrations of trace elements were usually significant between sampling sites except for As and Pb, and the mussels from Sanshandao site had mostly accumulated or were contaminated with essential and toxic elements. The residue level of Cd in A. woodiana from the Sanshandao and Manshan sites appeared to be even higher than those of the essential elements Cu and Se, and exceeded the corresponding maximum residue limits of China. The present study provides the most recent information on trace element bioaccumulation or contamination in Taihu Lake and, further, suggests that A. woodiana can be used as a suitable bioindicator for inland water environmental monitoring.
Tissue Injury and Cellular Immune Responses to Cadmium Chloride Exposure in the Common Mussel Mytilus edulis: Modulation by Lipopolysaccharide by S. K. Sheir; R. D. Handy (pp. 602-613).
The immunotoxic effects of cadmium (Cd) exposure in bivalves are poorly understood and whether or not stimulation of the immune system exacerbates Cd toxicity is unclear. The mussel Mytilus edulis was exposed to 20 or 50 μg/l total Cd for up to 11 days compared to no added Cd controls to assess immune and other physiological responses. Selected experiments were then repeated in the presence of a lipopolysaccharide (LPS) challenge with and without subsequent Cd exposure. Immune functions of hemocytes, hematology, hemolymph glucose and ion content, as well as superoxide dismutase (SOD) activity and organ pathology were measured. Cd accumulated mainly in digestive gland and gills and to a lesser extent in the adductor muscle. Exposure to 20 μg/l Cd alone caused a transient modulated of phagocytosis and increased neutral red retention (Kruskal–Wallis, p = 0.002). The higher Cd concentration also increased cytotoxicity, and decreased hemocyte count. Changes in hemolymph Na+, K+, and glucose were small or negligible. Histopathological examination showed tissue injuries consistent with inflammation and necrosis in the gills, digestive gland, and adductor muscle during Cd exposure alone. LPS injection alone and LPS + Cd caused an increase in the number of circulating hemocytes by the end of the experiment (Kruskal–Wallis, p = 0.01) and a transient rise in phagocytosis at day 4 (analysis of variance (ANOVA), p = 0.001). The LPS + Cd treatment also caused transient changes in neutral red retention and in the cytotoxicity of hemocytes compared to controls. Intracellular SOD activity did not change in hemocytes under any treatment. Tissue inflammation and pathology was greatly increased by the effect of Cd exposure with an LPS injection compared to either treatment alone. We conclude that immunostimulation with LPS can greatly increase Cd-related organ pathologies but does not necessarily alter the responses of hemocytes.
Evaluation of the Genotoxic Potential of the Mineral Coal Tailings Through the Helix aspersa (Müller, 1774) by Daniela Dimer Leffa; Adriani Paganini Damiani; Juliana da Silva; Jairo José Zocche; Carla Eliete Iochims dos Santos; Liana Appel Boufleur; Johnny Ferraz Dias; Vanessa Moraes de Andrade (pp. 614-621).
Coal mining is an activity with a high potential for environmental pollution. Coal has been described as the most significant pollutant of all the fossil fuels, containing a heterogeneous mixture. Many elements present in coal byproducts as well as coal tailings are rich in potentially toxic and genotoxic metals, which ultimately lead to profound changes in cells, tissues, populations, and ecosystems. The purpose of this study was to assess the genotoxic potential of the mineral coal tailings using the land snail Helix aspersa. Animals were divided in three groups, clustered in plexiglass cages: control (animals fed with organic lettuce), coal tailings (animals living in a layer of pyrite tailings and fed with organic lettuce), and mine lettuce (animals fed with lettuce grown in an area located in a deposit of coal tailings). The hemolymph was collected at different exposure times (24 h, 48 h, 72 h, 96 h, 1 week, 2 weeks, 3 weeks, and 1 month) for comet assay analyses. Results showed that the animals of the coal tailings and mine lettuce groups presented higher levels of DNA damage in relation to the control group at all exposure times, but with a peak of DNA damage in 48 h and 96 h. These results demonstrate that the coal pyrite tailings are potentially genotoxic and that H. aspersa has proven to be a sensitive instrument for a better risk assessment of environmental pollution.
Sensitivity of Lamprey Ammocoetes to Six Chemicals by Helle B. Andersen; Richard S. Caldwell; John Toll; Thai Do; Lisa Saban (pp. 622-631).
As part of the ecological risk assessment for Portland Harbor Superfund site, a study was conducted to address the question of whether the use of surrogate species in the risk assessment would be protective of lamprey ammocoetes. The study evaluated the acute toxicity of six chemicals: pentachlorophenol, copper, diazinon, aniline, naphthalene, and lindane; these chemicals represent the toxic modes of action of oxidative phosphorylation uncoupler, gill dysfunction, acetylcholinesterase inhibitor, polar narcosis, narcosis, and central nervous system interference, respectively. Field-collected lamprey ammocoetes were exposed to each of the six chemicals in a definitive 96-h flow-through acute water-only toxicity test. LC50s were calculated for pentachlorophenol at 31 μg/l, copper at 46 μg/l, diazinon at 8.9 mg/l, and aniline at 430 mg/l. Species sensitivity distributions based on LC50s for aquatic organisms indicated that lamprey ammocoetes were relatively sensitive to pentachlorophenol (15th percentile). The sensitivity of lamprey ammocoetes to copper approximated the average of aquatic species tested (46th percentile). Lamprey ammocoetes were relatively insensitive to diazinon and aniline (72th and 90th percentile, respectively). The 96-h LC50 for naphthalene was estimated at 10 mg/l, based on 50% mortality in the highest concentration. Based on a comparison with LC50s for four other fish species, ranging from 2.0 to 6.6 mg/l, lamprey ammocoetes were relatively insensitive to naphthalene. A 96-h LC50 could not be derived for lindane, with 12.5% mortality in the highest test concentration of 2.68 mg/l. LC50s for numerous other fish species ranged from 0.001 to 0.24 mg/l, indicating that lamprey ammocoetes were relatively insensitive to lindane. The study concluded that the use of surrogate species in the ecological risk assessment for Portland Harbor would be protective of lamprey ammocoetes.
Trace Metals (Cd, Cu, Ni, and Zn) in Blood and Eggs of the Sea Turtle Lepidochelys olivacea from a Nesting Colony of Oaxaca, Mexico by Federico Páez-Osuna; María F. Calderón-Campuzano; Martín F. Soto-Jiménez; Jorge R. Ruelas-Inzunza (pp. 632-641).
Trace metals (Cd, Cu, Ni, and Zn) concentrations were assessed in the sea turtle Lepidochelys olivacea from a nesting colony of Oaxaca, Mexico. Twenty-five female turtles were sampled, a total of 250 eggs were collected during the “arribada” event of the 2005–2006 season. Zn concentrations were highest in the yolk [72.3 ± 10.9 μg/g dry weight (dw)] and blood (58.4 ± 4.7 μg/g dw), whereas Ni concentrations were highest in the shell (48.5 ± 12.9 μg/g dw). The mean concentrations of Cu, and Cd in the analyzed tissues were lower than those reported in other sea turtle species. However, Zn and Ni concentrations in the yolk and shell, respectively, had the same distribution pattern observed at loggerhead and green turtles. On the basis of one nesting season, the maternal transfer and/or the excretion rates of trace metals via eggs-laying, estimated in terms of metal burdens in whole body, were 0.2, 7.8, 3.4, and 21.5% for Cd, Cu, Zn, and Ni, respectively.
Sex, Age, and Tissue Specific Accumulation of Eight Metals, Arsenic, and Selenium in the European Hedgehog (Erinaceus europaeus) by Anni Rautio; Mervi Kunnasranta; Anu Valtonen; Mirva Ikonen; Heikki Hyvärinen; Ismo J. Holopainen; Jussi V. K. Kukkonen (pp. 642-651).
Many insectivores have been shown to be sensitive to heavy metals and therefore suitable for biomonitoring purposes. In Finland, the hibernation period of the European hedgehog (Erinaceus europaeus) is long, and during hibernation the stress caused by environmental toxins may be crucial. Concentrations of cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), arsenic (As), and selenium (Se) were measured in a population of hedgehogs in the town of Joensuu in eastern Finland during the summers of 2004 and 2005. The analyzed tissues were kidney, liver, hair, and spine. The sampled hedgehogs (n = 65) were mainly road-killed animals. As expected, the concentrations of heavy metals were low because the hedgehogs were living in a comparatively unpolluted area. Significant increases with age were found in Cd concentrations (kidney, liver, and spine) and some essential elements (Se in spine, kidney, and liver; Mo in kidney and liver; Cu in spine; Fe in liver; and Mn in spine). Age accumulation and correlations between Se and Cd and between Mo and Cd may indicate the protective roles of Se and Mo against Cd toxicity in hedgehogs, in which Cd is already at comparatively low concentrations. Sex had no significant effect on concentrations of the elements studied. In conclusion, age is an important parameter to be taken into account when studying heavy-metal concentrations in hedgehogs and other insectivores.
Polychlorinated Biphenyls and Reproductive Performance in Otters From the Norwegian Coast by Hanne Christensen; Thrine Moen Heggberget; Arno C. Gutleb (pp. 652-660).
Eurasian otter (Lutra lutra) has shown decreasing population trends in most areas of Europe until recently, when populations in some areas started to recover. For Norway it was postulated that PCB concentrations in the south would be high and that levels in otters will show a geographic pattern that can be related to female otter reproductive health. Concentrations of PCBs (measured as the sum of 30 congeners ranging from 0.58 to 29 mg/kg lipid weight [geometric mean 6.18 mg/kg]) were lower than those found in otters from most other European countries. PCB concentrations did not decrease in otters collected during the period from 1979 to 1990. However, a south-to-north gradient of increasing PCB concentrations in otter livers was found along the Norwegian coast. Actual PCB concentrations had not affected the reproductive health of female otters (implanted embryos, implantation sites, regressive structures). This provides valuable information on PCB concentrations tolerated by Eurasian otters at the population level.
Role of Protein Kinase C in TBT-Induced Inhibition of Lytic Function and MAPK Activation in Human Natural Killer Cells by Abraham B. Abraha; Krupa Rana; Margaret M. Whalen (pp. 661-669).
Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposure of NK cells to tributyltin (TBT) greatly diminishes their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C (PKC) as well as MAPK activity. TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to a subsequent encounter with a target cell. In the present study we evaluated the involvement of PKC in inhibition of NK lysis of tumor cells and activation of MAPKs caused by TBT exposure. TBT caused a 2–3-fold activation of PKC at concentrations ranging from 50 to 300 nM (16–98 ng/ml), indicating that activation of PKC occurs in response to TBT exposure. This would then leave the NK cell unable to respond to targets. Treatment with the PKC inhibitor, bisindolylmaleimide I, caused an 85% decrease in the ability of NK cells to lyse tumor cells, validating the involvement of PKC in the lytic signaling pathway. The role of PKC in the activation of MAPKs by TBT was also investigated using bisindolylmaleimide I. The results indicated that, in NK cells where PKC activation was blocked, there was no activation of the MAPK, p44/42 in response to TBT. However, TBT-induced activation of the MAPKs, p38 and JNK did not require PKC activation. These results indicate the pivotal role of PKC in the TBT-induced loss of NK lytic function including activation of p44/42 by TBT in NK cells.
2,4,5-Trichlororophenol and Its Derivatives Induce Biochemical and Morphological Changes in Human Peripheral Blood Lymphocytes In Vitro by Jaromir Michałowicz (pp. 670-678).
In this work, the investigation of the effects of 2,4,5-trichlorophenol (2,4,5-TCP), 4,6-dichloroguaiacol (4,6-DCG), and 4,5-dichlorocatechol (4,5-DCC) on selected morphological and biochemical parameters in human peripheral blood lymphocytes were studied. All of the investigated compounds (at concentrations from 25–600 ppm) increased the size and granularity of the lymphocytes. 2,4,5-TCP induced the strongest and 4,5-DCC induced the weakest changes in these parameters. Moreover, 2,4,5-TCP induced the greatest loss of lymphocyte viability, which was statistically significant at concentrations of 125 and 600 ppm. DNA and protein damage was provoked by relatively low concentrations of the xenobiotics examined. Comet assay analysis showed that 4,6-DCG and 4,5-DCC at 5 ppm significantly increased the level of single- and/or double-strand breaks in the DNA of human lymphocytes. The increase in carbonyl group content (the marker of protein damage) was more strongly induced by 4,5-DCC and 2,4,5-TCP than by 4,6-DCG at concentrations ranging from 0.04 to 5 ppm. DNA and protein damage was most probably caused by reactive oxygen species (ROS) because it was observed that all of the compounds studied, as well as 4,5-DCC and 2,4,5-TCP in particular, were capable of oxidising fluorescent probe 6-carboxy-2′,7′-dichlorodihydrofluorescein at very low concentrations (0.01–1 ppm). In summary, 2,4,5-TCP induced the greatest morphological and cytotoxic changes in human peripheral blood lymphocytes, whereas its metabolite 4,5-DCC caused the most severe biochemical alterations, such as protein and DNA damage as well as ROS formation, in the incubated cells,.