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Archives of Environmental Contamination and Toxicology (v.51, #2)
Size Distributions of Soil Particles Adhered to Children’s Hands by Naomichi Yamamoto; Yuko Takahashi; Jun Yoshinaga; Atsushi Tanaka; Yasuyuki Shibata (pp. 157-163).
The size distributions of the soil particles adhered to children’s hands were preliminarily investigated and compared with a cutoff soil particle size recently specified in the official analytical method in Japan. To facilitate fieldworks involving child participants, we tested a methodology using a laser scattering particle size distribution analyzer and validated it for field applications. The laboratory experiments using this method showed finer soil particles tended to be adhered more efficiently to human hands. Meanwhile, our preliminary field survey revealed large variations in mass (mean 26.2 mg/hand, median 15.2 mg/hand, max 162.5 mg/hand) and size distributions (particle mode diameter of 39 ± 26 μm) of the particles adhered to children’s hands after various playing activities. Even though the ways the particles adhered were noticeably varied under actual playing situations, the adhered particles were consistently and considerably smaller than the 2-mm cutoff diameter defined by the Ministry of the Environment, Japan. Since soil contaminant concentrations are generally higher for finer soil particles, measurement of contaminant concentrations for the soil fraction including the non-adherent millimeter particles may underestimate the risk of direct soil contaminant intakes.
Effects of Application Methods of Metam Sodium and Plastic Covers on Horizontal and Vertical Distributions of Methyl Isothiocyanate in Bedded Field Plots by Li-Tse Ou; John E. Thomas; L. Hartwell Allen Jr.; Joseph C. Vu; Donald W. Dickson (pp. 164-173).
This study was conducted to examine the effects of three application methods of metam sodium (broadcast, single irrigation drip tape delivery, and double irrigation drip tape delivery) and two plastic covers (polyethylene film and virtually impermeable film) on volatilization and on horizontal and vertical distributions of the biologically active product of metam sodium, methyl isothiocyanate (MITC), in field plots in a Florida sandy soil. Volatilization of MITC from field beds lasted for about 20 hours after completion of metam sodium application regardless of application methods. Virtually impermeable film (VIF) was a better barrier to reduce volatilization loss than polyethylene film (PE). Since water was not applied during broadcast application, MITC was mainly retained in the shallow soil layer (0- to 20-cm depth) and downward movement of MITC was limited to about 30 cm. Large values of standard deviation indicated that initial spatial distribution of MITC in the root zone (10- and 20-cm depths) of the two broadcast applied beds covered with PE or VIF was variable. Twice more water was delivered through the single drip tape than through individual tapes of double drip tape treatments during drip application of metam sodium. More water from the single drip tape likely facilitated downward movement of MITC to at least 60-cm depth, but MITC did not penetrate to this depth in the double drip tape beds. On the other hand, horizontal distribution of MITC in the root zone (10- and 20-cm depths) in the double drip tape beds was more uniform than in the single drip tape beds. More MITC was retained in the subsurface of the VIF-covered beds regardless of application methods than in the PE-covered beds.
The Effect of pH on the Uptake and Toxicity of Copper and Zinc in a Tropical Freshwater Alga (Chlorella sp.) by Karyn L. Wilde; Jennifer L. Stauber; Scott J. Markich; Natasha M. Franklin; Paul L. Brown (pp. 174-185).
Copper and zinc toxicity to the freshwater alga Chlorella sp. was determined at a range of pH values (5.5–8.0) in a synthetic softwater (hardness 40–48 mg CaCO3/L). The effects of the metals on algal growth (cell division) rate were determined after 48-h exposure at pH 5.5, 6.0, 6.5, 7.0, 7.5, and 8.0. The toxicity of both metals was pH dependent. As pH decreased from 8.0 to 5.5, the copper concentration required to inhibit the algal growth rate by 50% (IC50) increased from 1.0 to 19 μg/L. For zinc, the IC50 increased from 52 to 2700 μg/L over the same pH range. Changes in solution speciation alone did not explain the increased toxicity observed as the pH increased. Modelled Cu2+ and Zn2+ concentrations decreased with increasing pH, whereas toxicity was observed to increase. Measurements of extracellular (cell-bound) metal concentrations support the biotic ligand model (BLM) theory of competition between protons (H+) and metals for binding sites at the algal cell surface. Higher extracellular metal concentrations were observed at high pH, indicating reduced competition. Independent of pH, both extracellular and intracellular copper were directly related to growth inhibition in Chlorella sp., whereas zinc toxicity was related to cell-bound zinc only. These findings suggest that the algal cell surface may be considered as the biotic ligand in further development of a chronic BLM with microalgae. Conditional binding constants (log K) were determined experimentally (using measured intracellular metal concentrations) and theoretically (using concentration-response curves) for copper and zinc for Chlorella sp. at selected pH values. Excellent agreement was found indicating the possibility of using concentration-response data to estimate conditional metal-cell binding constants.
Brominated Indoles and Phenols in Marine Sediment and Water Extracts from the North and Baltic Seas–Concentrations and Effects by N. Reineke; S. Biselli; S. Franke; W. Francke; N. Heinzel; H. Hühnerfuss; H. Iznaguen; U. Kammann; N. Theobald; M. Vobach; W. Wosniok (pp. 186-196).
This work presents results from analytical as well as ecotoxicologic investigations of sediment and water samples from the North and Baltic Seas. A bioassay-directed procedure was used to investigate cause–effect relationships between observed effects in acute laboratory bioassays (luminescent bacteria assay with Vibrio fischeri and embryo test with Danio rerio) and analyte concentrations in extracted samples. Brominated phenols and indoles—including 4-bromophenol; 2,4-dibromophenol; 4- and 6-bromoindole; 3,4-, 4,6-, and 3,6-dibromoindole; and tribrominated compounds—were identified in partly remarkable concentrations (up to 40,000 ng g−1 total organic carbon TOC for 4-bromophenol) in North Sea sediment samples and water samples (913 ng L−1 3,6-dibromoindole) from the German Bight. The toxicity of some of the identified brominated substances was low, with median effect concentration levels (EC50) ranging from 0.08 to 21.7 mg/L for V. fischeri and 4.3 to 46.3 mg/L for D. rerio. Comparison of the concentrations of analytes with ECs showed a toxicity contribution of brominated phenols and indoles to overall toxicity of the fraction. In the case of one water sample from the German Bight, brominated phenols and indoles accounted for the observed toxicity. Brominated phenols and indoles, which are assumed to be of biogenic origin, have rarely been discussed so far in the context of ecotoxicologic effects in marine ecosystems.
Land Use Influences and Ecotoxicological Ratings for Upper Clinch River Tributaries in Virginia by B. A. Locke; D. S. Cherry; C. E. Zipper; R. J. Currie (pp. 197-205).
The Clinch River system of southwestern Virginia and northeastern Tennessee is among the most biodiverse aquatic ecosystems of the United States, but its fauna are in decline. Unionidae (freshwater mussel) species are a major component of the Clinch’s aquatic community, and their decline is well documented. Point-source discharges within the Clinch drainage are few, and primary stressors on the biota are believed to originate from non–point sources that are transported into the mainstem by tributaries. Currently, the relative influences of tributaries as stressors on aquatic biota are unclear. We studied 19 major tributaries of the free-flowing Upper Clinch River, developed an Ecotoxicological Rating (ETR) utilizing eight parameters, and assessed stream quality among land use categories using the ETR rating system. Biological, toxicological, habitat, and chemical variables were measured in each tributary, near its confluence with the Clinch. Geographic Information System software was used to quantify land use within each tributary watershed; all tributary watersheds are predominately forested, but agricultural, mining, and developed land uses (urban, transportation) are also present. ETRs indicated that the tributaries draining mining-influenced watersheds had greater potential impact on the mainstem than those draining agricultural or forested watersheds, because of poor benthic macroinvertebrate scores. ETRs ranged from 44 to 63, on a 100-point scale, for mining-influenced tributaries compared to agricultural (57–86) and forested tributaries (64–91). Mean ETRs for the mining-influenced tributaries (51) were significantly different than ETRs from agricultural and forested streams (75 and 80, respectively), and the presence of developed land uses had no significant relationship with ETRs.
Monitoring Trace Metal Contaminants in Green Mussel, Perna viridis from the Coastal Waters of Karnataka, Southwest Coast of India by Geetha Sasikumar; P. K. Krishnakumar; G. S. Bhat (pp. 206-214).
The green mussel (Perna viridis) is widely distributed in the coastal waters of Asia and is used in mussel watch programmes for monitoring environmental contaminants throughout the region. Green mussels representing different size groups and habitats were sampled from their natural beds at 28 locations in the inshore waters of Karnataka (southwest coast of India) to analyze the tissue concentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn. Tissue concentrations of Cr, Cu, Fe, and Pb were significantly higher in smaller mussels than in the larger size group. Significantly higher concentrations of Cr, Cu, Fe, Mn, and Ni were observed in mussels sampled from intertidal beds when compared to mussels from the subtidal beds. The sampling sites were categorized into industrial sites (IS), urban sites (US), and nonurban sites (NS) based on principal component analysis of metal concentrations in mussel. Spatial variations in tissue concentrations of all metals were observed except for Zn. Generally, the levels of toxic trace metals like Pb, Cd, Ni, and Cr in the whole tissue of P. viridis were within safe limits throughout the coast of Karnataka. However, relatively high concentrations of Cd, Cr, and Pb were observed in the whole tissue of green mussels collected from the industrial sites (IS), which may be derived from a variety of anthropogenic activities.
Control of Modiolid Mussels in Cooling Water Systems by Continuous Chlorination by S. Rajagopal; V. P. Venugopalan; G. van der Velde; H. A. Jenner (pp. 215-222).
Modiolid mussels such as Modiolus philippinarum and Modiolus metcalfei constitute a numerically significant group in fouling communities, especially in tropical and subtropical industrial cooling water systems. Nevertheless, there are hardly any published reports on the tolerance of these species to chlorination or biofouling control measures, This article provides data on the mortality pattern (LT50 and LT100) and physiological activities (oxygen consumption, filtration rate, foot activity, and byssus thread production) of different size groups of M. philippinarum (7- to 30-mm shell lengths) and M. metcalfei (6- to 26-mm shell lengths) exposed to different concentrations of residual chlorine (0.25, 0.50, 0.75, and 1.00 mg/L for sublethal responses; 1, 2, 3, and 5 mg/L for mortality). It is shown that exposure time for 100% mortality of M. philippinarum and M. metcalfei significantly decreased with increasing residual chlorine concentration. For example, 30-mm size group M. philippinarum exposed to 1 mg/L chlorine residual took 402 h to reach 100% mortality, whereas those exposed to 5 mg/L chlorine took 108 h. Among the two mussels, M. philippinarum showed slightly higher tolerance (9–20%) to chlorine when compared to M. metcalfei. The effect of mussel size on mortality of M. philippinarum was significant, with the larger size group mussels showing greater resistance than smaller ones. However, in M. metcalfei, size of the mussel does not seem to be a determinant of its chlorine tolerance. All size groups of M. philippinarum and M. metcalfei showed progressive reduction in physiological activities (oxygen consumption, filtration rate, foot activity index, and byssus thread production) when chlorine residuals gradually increased from 0 to 1 mg/L. Reduction in physiological activities was strongly correlated with chlorine concentration. A comparison of present data with data available for other coexisting mussel species suggests that M. philippinarum and M. metcalfei are relatively less tolerant to chlorine than Perna viridis, Perna perna, and Brachidontes striatulus, which also cause fouling problems in tropical coastal waters.
Concentrations of Polychlorinated Biphenyl Congeners in Cultivated Oysters (Crassostrea gigas) in Western Taiwan by M. D. Fang; H.-T. Fang; C.-L. Lee; F.-C. Ko; J. E. Baker (pp. 223-231).
Spatial and temporal variations of polychlorinated biphenyl (PCB) concentrations in cultivated oysters from five aquaculture areas along the western coast of Taiwan were investigated. Poor correlations between total PCB concentrations (ng/g dry weight [dw]) and physiologic parameters of oysters (shell length, width, thickness, and lipid content) were found. Total PCB concentrations ranged from 3.4 to 94 cng/g dw. The highest value was found in oysters from the Lu’ermen aquaculture area, which receives wastewater from a sodium hydroxide and pentachlorophenol factory. Furthermore, principal component analysis confirmed that the PCB congener pattern in this area was distinct from others and that two additional pollution sources might exist in the Tainan and Hsinchu areas. Oysters with PCB concentrations > 1 SD above the geometric mean were found mainly in Tainan (stations TN5 to TN9) with only one increased concentration in the Yunlin (station YL2) and Hsinchu (station HC4) aquaculture areas. Except for four confined stations, TN3 to TN6, where total PCB concentrations were higher (p = 0.028) in the warmer (May and July) than in the colder season (November and March), seasonal variation of total PCB concentrations in oysters was not significant. Geometric mean and geometric mean plus 1 SD of total PCB concentrations in this study are lower than those in South Korea and the United States (Mussel Watch).
Polycyclic Aromatic Hydrocarbon Metabolites and 7-Ethoxyresorufin O-Deethylase Activity in Caged European Eels by H. Fenet; E. Gomez; D. Rosain; C. Casellas (pp. 232-236).
This study investigated the contribution of two biomarkers, bile polycyclic aromatic hydrocarbon (PAH) metabolites and 7-ethoxyresorufin O-deethylase (EROD), activity in the assessment of PAH contaminated sites. European eels (Anguilla anguilla) were caged in a freshwater stream upstream and downstream from local industrial effluent outlets. Bile PAH metabolites were recorded as fluorescent aromatic compounds by synchronous fluorescence spectroscopy and as a marker for total PAH metabolism: 1-hydroxypyrene (1-OH Pyr) was isolated by high-pressure liquid chromatography and quantified. After 14 and 28 days of caging, EROD activity, bile fluorescence (synchronous fluorometric measurement), and 1-OH Pyr concentrations in bile were higher at the downstream site than at the upstream site. This increase was similar after 2 and 4 weeks of caging. During a reversibility study, EROD activity, bile fluorescence, and 1-OH Pyr concentrations decreased, and this trend was similar for the three markers. These results suggest that PAHs could be the main factor responsible for EROD induction in eels caged at the downstream site.
Comparison of Vitellogenin Induction, Sex Ratio, and Gonad Morphology Between Zebrafish and Japanese Medaka After Exposure to 17α-Ethinylestradiol and 17β-Trenbolone by S. Örn; S. Yamani; L. Norrgren (pp. 237-243).
The pharmaceutical estrogen 17α-ethinylestradiol (EE2) and the anabolic androgen 17β-trenbolone (Tb) can interfere with the endocrine and reproductive systems of fish. The potency of these chemicals in zebrafish (Danio rerio) and Japanese medaka (Oryzias latipes) was assessed using the core end points vitellogenin (Vtg) concentration at 38 days post-hatch and sex ratio and gonad morphology at 60 days post-hatch. Vtg concentrations were measured in fish whole-body homogenate samples using enzyme-linked immunosorbent assay. Increased Vtg concentration and feminization of fish after exposure to 10 ng/L EE2, as well as masculinization after exposure to 50 ng/L of Tb, were observed in zebrafish. Intersex was observed in medaka exposed to EE2. A decrease in Vtg production after Tb exposure (50 ng/L) was measured in both zebrafish and medaka. Analyses of gonad morphology revealed increased testicular area and sperm percentage in Tb-exposed zebrafish, whereas increased sperm percentage was measured in Tb-exposed medaka. The higher sensitivity of zebrafish compared with medaka to both EE2 and Tb was revealed in the study.
Fate and Effects of 2,4,6-Trinitrotoluene (TNT) from Dumped Ammunition in a Field Study with Fish and Invertebrates by Helene Ek; Göran Dave; Eva Nilsson; Joachim Sturve; Göran Birgersson (pp. 244-252).
2,4,6-Trinitrotoluene (TNT) is the major explosive ingredient in ammunition dumped into lakes and sea after World War II. The aim of the present field study was to study the fate and effect of TNT and its degradation products from dumped ammunition. Artillery shells were cleaved longitudinally to expose TNT and placed in open boxes filled with sediment, and then placed at the sea bottom. Sediment samples were taken in each box at the start and after 3, 9, 13, 20, 24, 33, and 36 months, and the sediments were tested for toxicity with bioassays using Nitocra spinipes (96 h), Hyalella azteca (96 h), and Daphnia magna (24 and 48 h). The result from the bioassays showed no impact of dumped ammunition on the survival of H. azteca and mobility of D. magna. Bioassays with N. spinipes showed significant differences in toxicity between control boxes and boxes with shells after 9 months and thereafter. The mean mortality (± SD) of N. spinipes in boxes with shells was 63 ± 22%, and the mortality in control boxes was 23 ± 17%. No continuous increase in sediment toxicity over time was found. After 3 years, cages with European flounder (Platichtys flesus) and blue mussels (Mytilus edulis) were attached to the boxes. The fish were examined for biochemical and physiological effects 8 weeks later. Exposure to ammunition, which had rested on the sea bottom 3 years, caused no significant effects on body indices, hematological variables, and detoxification and antioxidant enzymes activities in the flounder. The sediment, bile, and blood plasma of exposed fish, and hepatopancreas of exposed mussels, contained no detectable levels of TNT and its metabolites. Only minor disappearance of TNT from the shells could be detected by visual inspection on site (by scuba divers). This study suggests that the survival of sensitive benthic organisms, e.g., N. spinipes, might be negatively affected at an ammunition dumping site.
The Effect of 17β-Estradiol on the Development of Modified Hemal Spines in Early–Life Stage Gambusia holbrooki by Christopher A. Rawson; Richard P. Lim; Michael St. J. Warne; Christopher J. Doyle (pp. 253-262).
The morphologic development of the gonopodium of male mosquitofish, Gambusia holbrooki, is essential for proper reproductive function and has previously been used as a biomarker for the presence of endocrine-disrupting chemicals (EDCs) in freshwater systems. The development of the gonopodium is accompanied by the modification of the hemal spines on the 14th, 15th, and 16th vertebrae. These form an anchor for the movement of the gonopodium, and their normal development is therefore critical. This development is under hormonal control. It has been hypothesized that the modification of the hemal spines may be used as an end point for understanding the effects of exposure of early–life stage fish to EDCs and to add to the understanding of the differential sensitivities of different life stages. Larval fish were exposed to concentrations (0, 20, 100, and 500 ng/L) of 17β-estradiol (E2) in two experiments using a flow-through system for 8 and 12 weeks. There was a general delay in the development of the three hemal spines when exposed to high concentrations of E2. However, this delay was not observed for all end points on a particular spine nor across all spines. Fish examined at 8 weeks postpartum showed a more extensive delay at high concentrations than those examined at 12 weeks postpartum, suggesting that later in the life cycle, high levels of exogenous E2 may be overcome by increasing levels of endogenous androgen. There was a decrease in the number of phenotypic male fish present in the 500-ng/L treatment at 12 weeks postpartum and an apparent decrease in the degree of sexual differentiation at high levels of E2 exposure. The results suggest that effects of EDC exposure begin very early in a fish’s life cycle.
Chronic Exposure to Coal Fly Ash Causes Minimal Changes in Corticosterone and Testosterone Concentrations in Male Southern Toads Bufo terrestris by C. K. Ward; M. T. Mendonça (pp. 263-269).
More than 50% of the electricity in the United States is produced by coal-burning power plants. The byproduct of coal-burning plants is coal fly ash, which contains increased concentrations of trace metals and is disposed of in collection basins. Southern toads (Bufo terrestris) frequently use these basins for reproduction. Male toads were collected in spring 2001 and 2002 from an ash basin and a reference site and divided into four groups: toads collected at the control site and maintained on (1) control substrate and food or (2) ash and contaminated food and toads collected at the ash site and maintained in (3) control or (4) ash conditions. Blood was collected periodically during 5 months to determine testosterone and corticosterone concentrations. Reference to ash toads exhibited a significant, transient increase in corticosterone at 4 weeks, but neither corticosterone nor testosterone continued to increase beyond this time. In contrast, toads caught and maintained on ash did not exhibit increased corticosterone. Testosterone in these toads appeared to be unrelated to ash exposure. This unexpected lack of a corticosterone response and no effect on testosterone suggests that toads chronically exposed to trace metals can acclimate to a polluted environment, but they may still experience subtle long-term consequences.
Polychlorinated Biphenyl Concentrations, Congener Profiles, and Ratios in the Fat Tissue, Eggs, and Plasma of Snapping Turtles (Chelydra s. serpentina) from the Ohio Basin of Lake Erie, USA by H. Dabrowska; S. W. Fisher; J. Estenik; R. Kidekhel; P. Stromberg (pp. 270-286).
Concentrations and profiles of polychlorinated biphenyls (PCBs) were determined in three tissues of adult snapping turtles (Chelydra serpentina serpentina) from six locations in the Ohio Basin of Lake Erie to characterize tissue variation and geographic trends. The locations included the Ohio Areas of Concern, i.e., the Ashtabula, Black, and Maumee Rivers; the Ottawa River near Toledo; and two reference sites. Mean total PCBs were greatest in turtles from the Ottawa River followed by the Maumee, Ashtabula, and Black Rivers. All three types of samples—fat tissue (FT), eggs, and plasma—showed the same geographic trend in PCB levels. On a wet-weight basis, mean concentrations ranged from 2148 to 18,669 ng/g in FT, from 183 to 3683 ng/g in eggs, and from 18 to 201 ng/g in plasma. Across all sites, total PCB concentrations between the tissues were significantly correlated (0.001 < p < 0.005; Pearson correlation coefficient (rP) was between 0.720 and 0.954). Two distinctly different profiles with respect to relative congener and homologue concentrations were found among the sites. One that included four of the six sites examined was characterized by hexa-chlorobiphenyl (hexa-CB) dominance followed by hepta-CBs, with PCBs no. 138 + 163, 153 + 132 + 105, and 180 being the most abundant congeners. The second profile, specific for turtles from the Ottawa River, was different from the first in that tetra-CBs were the most abundant congeners followed by hexa-CBs. Analysis of variance (ANOVA) indicated significant intertissue differences in the PCB homologue profiles, i.e., FT had a higher percentage of hepta-, octa-, and nona-CBs compared with eggs and plasma, whereas eggs showed a higher percentage of hexa-CBs. At any listed location, FT, eggs, and plasma had the same congener profile. An intertissue distribution of lipid-normalized individual congener concentrations examined by regression analyses revealed significant egg–FT, egg–plasma, and FT–plasma relations for >40 congeners (0.001 < p < 0.05). The distribution ratios determined for these congeners from the slope of the regression lines averaged 1.235 ± 0.279, 0.430 ± 0.170, and 0.387 ± 0.115, respectively. The plasma wet weight–FT lipid-normalized concentration ratios for these congeners averaged 0.012 ± 0.006. Both egg–FT and plasma wet weight–FT lipid-normalized ratios regressed against log Kow showed significant decreases, with increasing log Kow, indicating greater accumulation of highly chlorinated congeners in FT than in other compartments. The estimated 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents ranged from 0.007 ng/g at reference sites to 0.060 ng/g at contaminated sites and from 0.099 to 1.992 ng/g in plasma and eggs, respectively. In both plasma and eggs, coplanar-CBs were the major contributors to total toxic equivalents (TEQs). Eggs from all contaminated sites had TEQs that exceeded the lowest observed effect level TEQs proposed for bald eagle chicks, in addition to high ΣPCB levels at some of these sites, especially the Ottawa and Maumee River sites, indicate potentially increased risk to turtles and possibly other wildlife species inhabiting these ecosystems. Significant correlations of total PCBs and individual congeners between FT, eggs, and plasma indicate that blood sampling can provide a good nonlethal measure of PCB exposure and can be used to monitor environmental contamination.
Selected Haematological and Biochemical Parameters of Blood in Rats After Subchronic Administration of Vanadium and/or Magnesium in Drinking Water by Agnieszka Ścibior; Halina Zaporowska; Jarosław Ostrowski (pp. 287-295).
The purpose of these studies was to evaluate the effect of selected vanadium and magnesium doses on certain haematological and biochemical blood parameters in rats. Outbred 2-month-old, albino male Wistar rats received for a period of 6 weeks, as a sole drinking liquid, the following water solutions: group II, sodium metavanadate (SMV) at a concentration of 0.125 mg V/mL; group III, magnesium sulphate (MS) at a concentration of 0.06 mg Mg/mL; and group IV, SMV-MS solution at the same concentrations. The control group received at this time deionized water to drink. It was calculated that group II ingested with drinking water about 10.7 mg V/kg b. w./24 h, group III 6 mg Mg/kg b. w./24 h, and group IV about 9 mg V and 4.5 mg Mg/kg b. w./24 h. The exposure to vanadium alone (group II) led to a statistically significant decrease in body weight gain, food and fluid intakes. Moreover, in the same group of rats a statistically significant decrease in the RBC count, Hb concentration, MCV, and MCH values was demonstrated. Additionally, a statistically significant decrease in the plasma L-ascorbic acid concentration and a significant increase in MDA concentration in blood in this group were found. Instead, after the administration of magnesium alone (group III), a statistically significant decrease in the fluid intake and in the L-ascorbic acid concentration in plasma was noted. Furthermore, in the same group of rats a statistically significant increase in Hb level and in the plasma magnesium concentration was demonstrated. Two-way analysis of variance (ANOVA) did not reveal the interactions between V and Mg.
Human Blood Monitoring Program in Japan: Contamination and Bioaccumulation of Persistent Organochlorines in Japanese Residents by T. B. Minh; M. Watanabe; N. Kajiwara; H. Iwata; S. Takahashi; A. Subramanian; S. Tanabe; S. Watanabe; T. Yamada; J. Hata (pp. 296-313).
Concentrations of persistent organochlorines (OCs)—such as polychlorinated biphenyls (PCBs), 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene, and tris(4-chlorophenyl)methane [TCPMe]—were determined in plasma samples from residents of three sub-metropolitan locations in Japan (Miyako, Saku, and Tottori) for the purpose of studying the geographic variation and specific accumulation of OCs. Residue concentrations of PCBs and DDTs were the highest in samples collected in Saku (400 and 370 ng/g lipid wt, respectively) whereas samples from Miyako contained greater CHL residues (70 ng/g lipid wt) than those from the other two locations. This contamination pattern reflects the historic use of OCs in each area. For the first time, tris (4-chlorophenyl) methane (TCPMe) concentrations were detected in most of the plasma sample analyzed. Concentrations of TCPMe which ranged from <0.1 to 8.1 ng/g lipid wt eight, were lower than those previouly reported in other human tissue. Larger geographic differences in OC accumulation were observed for PCBs and CHLs, whereas DDTs and HCHs exhibited little variability. PCB concentrations in samples from Saku residents were higher than those from residents of countries in the circumpolar Arctic region but lower than those reported for some populations in the United States and Western European countries. Interestingly, CHL residue concentrations in human blood from Japan are among the highest values reported for the countries examined, suggesting continued increased exposure to CHLs of the Japanese population. Time-trend analysis of CHLs in human blood samples from Miyako (Okinawa prefecture) showed that CHL residues have decreased substantially during the last decade, indicating the effect of the official ban of CHLs in 1986 in Japan. Isomer-specific analysis of PCBs revealed lower proportions of higher chlorinated congeners such as hepta- and octachlorobiphenyls in women than in men, suggesting the possibility of preferential elimination of higher chlorinated biphenyls in women. The difference in sex-dependent accumulation of OC compounds in healthy and ill persons was suggested. To our knowledge, this is the first report on the specific accumulation of persistent QCs, including TCPMe, in human blood samples from Japan.
Multivariate Statistical Analysis of Metal Concentrations in Teeth of Residents of Silesian Region, Southern Poland by D. Wiechuła; A. Fischer; J. Kwapuliński; K. Loska; T. Fischer; P. Kurpas (pp. 314-320).
Concentrations of 11 metals (Cd, Cr, Cu, Fe, Mn, Pb, Zn, Na, K, Ca, and Mg) were assayed in the teeth of two populations of the Silesian region. The first group (n = 83) comprised the residents of Katowice–Szopienice, a town located in the center of the Upper Silesian industrial region, in close proximity to a Pb plant, whereas the other was a group of residents of the agricultural community Strumień (n = 44). The concentrations of all the trace metals were found to be higher in the teeth of Katowice–Szopienice residents. The methods of cluster analysis distinguished two clusters of metals in the teeth: essential (Ca, Na, Mg, Zn, and K) and trace (Cd, Mn, Cr, Cu, Fe, and Pb) elements. Euclidean distances reflected the differences in concentrations between the two groups. The results obtained were analyzed using principal component analysis. Four principal factors accounted for 68.1% of the total variance for Katowice–Szopienice residents and for 80.1% for Strumień residents. The first factor showed high contributions of Cu and Cr, elements present in humans as a result of diet, and also Mn for Katowice–Szopienice residents because of environmental contamination. The second factor was characterized by large Zn and Cd fractions and, for Katowice–Szopienice residents, Pb and K as well. The diversified exposure of both populations was reflected by the differences in Euclidean distances and contribution of particular elements with respect of principal components.