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Archives of Environmental Contamination and Toxicology (v.43, #4)
TNT, RDX, and HMX Decrease Earthworm (Eisenia andrei) Life-Cycle Responses in a Spiked Natural Forest Soil by P. Y. Robidoux; J. Hawari; G. Bardai; L. Paquet; G. Ampleman; S. Thiboutot; G. I. Sunahara (pp. 0379-0388).
Sublethal and chronic toxicities of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) on earthworm Eisenia andrei in a sandy forest soil were assessed. Various reproduction parameters of fecundity (total and hatched number of cocoons, number of juveniles, and their biomass) were significantly decreased by TNT (≥ 58.8 ± 5.1 mg/kg dry soil), RDX (≥ 46.7 ± 2.6 mg/kg), and HMX (≥ 15.6 ± 4.6 mg/kg). These effects occurred at much lower concentrations than those reported earlier using artificial soil preparations. Growth of adults was significantly decreased in the TNT-spiked natural soils at 136.2 ± 25.6 mg/kg dry soil, the highest concentration having no significant mortality. In contrast, survival and growth were not significantly reduced at relatively high measured concentrations of RDX (167.3 mg/kg) and HMX (711.0 mg/kg). Although TNT, RDX, and HMX share a common life-cycle response (i.e., decreased juvenile counts), a number of differences related to other reproduction parameters (e.g., productivity of cocoons) was observed. These results indicate that the tested explosives do not support a common mechanism of toxicity, at least in the earthworm, probably due to differences in their physical-chemical properties as well as metabolites formed during exposure.
Remediation of Heavy Metal-Contaminated Soils Using Phosphorus: Evaluation of Bioavailability Using an Earthworm Bioassay by K. A. Maenpaa; J. V. K. Kukkonen; M. J. Lydy (pp. 0389-0398).
This study investigated the effectiveness of phosphorus (P) as an in situ remediation technique in site soils collected from the Tri-State mining area. The site soils were treated with two different types (KH2PO4 and Super Triple Phosphate fertilizer) and levels (600 and 5,000 mg/kg) of phosphorus. A toxicokinetic approach was used to determine whether phosphorus amendments reduced heavy metal bioavailability to the earthworm Eisenia fetida. Bioaccumulation factors were used as a measure of bioavailability. Depuration patterns of lead, zinc, and cadmium also were studied after removing earthworms from contaminated soils and then placing them in noncontaminated artificial soil. Results showed that the high phosphorus treatments significantly reduced lead, zinc, and cadmium bioavailability to the earthworms, probably due to formation of metal-phosphate complexes in the soils. Results also indicated that other soil characteristics in addition to amended phosphorus have an affect on bioavailability. Depuration experiments showed a biphasic elimination pattern for each metal. The current results indicate that phosphorus soil amendments may reduce ecological risk to soil-inhabiting invertebrates exposed to heavy metal-contaminated soils.
In Vitro Lead Bioaccessibility and Phosphate Leaching as Affected by Surface Application of Phosphoric Acid in Lead-Contaminated Soil by J. Yang; D. E. Mosby; S. W. Casteel; R. W. Blanchar (pp. 0399-0405).
Phosphate treatment of lead-contaminated soil may be a cost-effective remedial alternative for in situ stabilizing soil Pb and reducing Pb toxicology to human. The leaching behaviors of the P added to soil surface and the effect on subsurface Pb bioaccessibility must be addressed for this remedial technology to be acceptable. A smelter-contaminated soil containing an average of 2,670 mg Pb kg−1, collected from the Jasper County Superfund Site located in Jasper County, Missouri, was surface treated with 10 g P kg−1 as phosphoric acid (H3PO4). Following a simulated column leaching and 90-day treatment of field plots, respectively, bioaccessible Pb, P, and pH in soil profile were measured. Surface treatment using H3PO4 effectively stabilized soil Pb and reduced leachable Pb and the bioaccessibility. Phosphate leached into deeper profile significantly lowered bioaccessible Pb in subsurface. Reduction of Pb bioaccessibility increased as a linear function of increasing soil P. Although surface H3PO4 treatment resulted in an enhanced leaching of added P and may increase potential risk of surface and groundwater pollution, the P leaching under field conditions is very limited. Lime addition following the treatment may reduce the leachability of added P and further immobilize soil Pb.
Total and Toxic Arsenic Levels in North Sea Fish by M. De Gieter; M. Leermakers; R. Van Ryssen; J. Noyen; L. Goeyens; W. Baeyens (pp. 0406-0417).
Levels of arsenic contamination in muscle and liver tissue of 25 sea fish and 4 shellfish species from the North Sea were determined. Analyses were done by both ICP-MS and HG-AFS to distinguish between nontoxic and toxic fractions of As. Highest total As concentrations were found in lemon sole, dogfish, ray, and witch. Average total As concentrations in these fish species were higher than 20 mg kg−1 WW. The same species as well as the other flatfishes contained the highest amounts of toxic As (> 0.1 mg kg−1 WW). Toxic fractions (AsTox/AsT%) above 2% were found in the following six species: seabass, ling, john dory, pouting, dab, and brill. No preferential concentration in the liver compared to the muscle was observed.In a worst-case scenario (when fish has been dried or smoked and the toxic As level is high; for example 0.5 mg kg−1 WW), the As content of North Sea marine food may reach harmful levels. A normalization reflecting the toxic potential of sea fish was made. Shark and ray and most flatfish species have positive (high) normalized AsTox values.By ANOVA testing we compared the individual AsT concentrations of samples of the same species (intraspecies variability). Significant differences for some fish species were observed; significantly higher AsT concentrations were found in dogfish from the French coast versus the western North Sea and in common sole from the Bay of the Seine, in the north of France, versus the western North Sea.
Baseline Measurements of Indicators for Sublethal Effects of Metals in Lake Whitefish (Coregonus clupeaformis) by H. M. Cooley; R. E. Evans; J. F. Klaverkamp (pp. 0418-0424).
Histological and metallothionein (MT) analyses of liver and kidney and measurements of serum electrolytes and hematocrit from lake whitefish (Coregonus clupeaformis), 3.5 years of age, were conducted over a 90-day period that included maximal gonadal maturation in females. Condition factors were higher in females at day 1 and when all data were combined over the 90-day sampling period. Significant differences between females and males of 1.8-fold in hepatic MT concentrations were observed at day 20 when ovaries appeared to be in the most advanced state of maturation, although this parameter was not quantified. Hematocrits were slightly but significantly lower at day 90. No sex differences were observed in the quantitative assessments of epithelium cell height, lumen diameter (LD), tubule diameter (TD), and ratio of LD:TD in the second segment of the proximal tubule (P2); and of hepatocyte area, hepatocyte nuclear diameters, and nucleus area:cytoplasmic area (N:C) ratio. Positive correlations were observed between N:C ratios and fish weight, fork length, and liver weight. No significant correlations between these histological morphometrics and MT concentrations were observed in liver or kidney. The results of this study provide baseline information for investigations designed to determine sublethal effects of metals in lake whitefish.
Biodegradability Assessment of Ozonated Raw and Biotreated Pharmaceutical Wastewater by I. Arslan-Alaton; I. Akmehmet Balcioglu (pp. 0425-0431).
The activated sludge specific oxygen uptake rate (SOUR) and BOD5/COD ratios of biologically pretreated pharmaceutical wastewater were analyzed and compared to assess relative changes in biotreatability during ozonation at a rate of 7.4 g/(L × h) for 4 h. An appreciable COD removal (41%) was achieved by the initial biological treatment process, whereas ozonation was more effective in reducing the UV-sensitive aromatic compounds present in the pretreated effluent. Sequential treatment using activated sludge + ozonation processes resulted in an average COD removal efficiency of 48%, and a proceeding biotreatment stage increased the overall COD removal to 53%. An optimum ozone dose in the range of 1,854–3,708 mg/L corresponding to a specific ozone input rate of 0.23–0.46 mg O3/mg CODo existed where SOUR (3.7 × 10−3 mg O2/[mg MLSS × min] for ozonation at pH 8) and BOD5/COD (0.57) as well as the proceeding biological COD removal yield Y COD (average 8 mg COD/mg MLSS) exerted maximum values.
Biological Monitoring of Environment Exposure to Safrole and the Taiwanese Betel Quid Chewing by M. J. W. Chang; C. Y. Ko; R. F. Lin; L. L. Hsieh (pp. 0432-0437).
A rapid and sensitive biological monitoring (BM) method for assessing exposure to the environmental carcinogen safrole has been developed. The method is an isocratic high-performance liquid chromatographic (HPLC) analysis of urinary dihydroxychavicol (DHAB) and eugenol, the urinary metabolites of safrole. Good linearity, precision, and accuracy were demonstrated. A recovery of 98.8 ± 5.4% (SD, n = 3) was found for DHAB and 84.1 ± 3.4% (n = 3) for eugenol. The quantitation limits of the method were 8 ng for DHAB and 10 ng for eugenol. The validity of the method was demonstrated by a linear dose-response relationship observed in rats given oral doses of safrole at 30, 75, and 150 mg/kg body weight. The method was also used to monitor the environmental exposure to the Taiwanese betel quid (TBQ) chewing, because TBQ used in Taiwan not only contains areca (betel) nut, slaked lime, and catechu but also Piper betle inflorescence or its leaves. Both of the latter have a high content of safrole. The feasibility of the method to monitor TBQ chewing was demonstrated by an analysis of 153 spot human urine samples. The results showed that the p value of the nonparametric group comparison was < 0.001 for DHAB and 0.832 for eugenol. The TBQ chewers also exhibited a significantly higher rate of urinary DHAB (but not eugenol) than the nonchewers with an odd ratio of 3.47 (95% CI, 1.61–7.51). However, when only the eugenol-positive subjects were taken into analysis, the ratio rose to 24.38 (95% CI, 3.00–197.90).
Origin and Distribution of Polycyclic Aromatic Hydrocarbons in Surficial Sediments from the Savannah River by M. Sanders; S. Sivertsen; G. Scott (pp. 0438-0448).
Surface sediments collected from the Savannah River, located in the southeastern state of Georgia, USA, in June–July 1994 were analyzed for individual polycyclic aromatic hydrocarbons (PAHs). Three subdivisions of the river were identified for the study: upstream from, adjacent to, and downstream from the city of Savannah. There was high spatial variability in the total PAH (ΣPAH) concentrations that ranged from 29 to 5,375 ng/g with an average concentration of 1,216 ± 1,161 (SD). Of the three subdivisions, the highest ΣPAH concentrations were in the middle segment, which was adjacent to urban and industrial areas. To elucidate sources, molecular indices based on indices among phenanthrene versus anthracene and fluoranthene versus pyrene were used to determine pyrogenic and petrogenic sources, respectively. These indices have been used by other authors to differentiate sources. In most cases, PAHs in sediments nearest the city of Savannah were of high temperature and pyrogenic origin. These pyrogenic PAHs were highly associated with toxicity to benthic organisms. The two-ringed naphthalene and substituted naphthalenes, which are petroleum-related PAHs, were significantly higher in the lower section of the river relative to the subdivisions. This river segment receives inputs primarily from shipping and boating traffic. Perylene, which is indicative of nonanthropogenic terrestrial inputs of carbon, had the highest concentration among the individual PAHs measured. High perylene concentrations were found at stations located upstream and adjacent to forested terrain and where salinity level was low. To discriminate pattern differences and similarities of individual PAHs among samples, principal component analysis (PCA) was performed on the more hydrophobic and persistent nonalkylated PAHs. These differences and similarities were used to infer perylene origin. PCA was performed on 14 nonalkylated PAHs that was normalized to the sum of nonalkylated PAHs, using a correlation matrix. Generally, the PAHs were separated into group patterns according to chemical and physical properties associated with log K OW, except perylene. Perylene, a five-ringed PAH, was distinctly separated from the other five-ringed PAHs. The sources for perylene are likely from biogenic, terrestrial precursors. The collected data show that pyrogenic PAHs were highly associated with biological effects on benthic organisms, based on bioassay results. Perylene, a nonanthropogenic PAH, was found throughout the river and constituted a large percentage of total PAHs in the upper river.
Mineralization of Clapper Rail Eggshell from a Contaminated Salt Marsh System by A. B. Rodriguez-Navarro; K. F. Gaines; C. S. Romanek; G. R. Masson (pp. 0449-0460).
The effect of contamination on eggshell mineralization has been studied for clapper rails (Rallus longirostris) inhabiting a contaminated salt marsh in coastal Georgia. To assess the impact of contaminants, the thickness, microstructure (crystal orientation), mineral composition, and chemistry of shell material were analyzed from a contaminated site and a nearby reference site using optical microscopy, X-ray diffraction, inductively coupled plasma mass spectrometry, and gas chromatography with electron capture detector. Eggshells from the contaminated site were generally thinner than those from the reference site. Also, eggshells from the contaminated site were abnormally brittle and contained anomalous microstructural attributes. The combination of reduced shell thickness and anomalous microstructure resulted in weaker eggshells, which in turn could pose a significant threat to the reproductive success of the affected population.PCB concentrations in eggshells were at background levels in both sites. Eggshells from the contaminated site had higher concentrations of heavy metals, specifically mercury, than the reference site. The structural changes observed in eggshells may be related to the concentration of specific metals (e.g., Mg, Cu, Zn, Pb, and Hg) in shell, however, statistical analyses indicated that metals only explained a small portion of the observed variation in properties (i.e., thickness, crystal orientation). Further analysis is required to better constrain the factors leading to unusually weak eggshells in the contaminated site.
Health Risk Assessment of PCDD/PCDF Exposure for the Population Living in the Vicinity of a Municipal Waste Incinerator by J. L. Domingo; M. C. Agramunt; M. Nadal; M. Schuhmacher; J. Corbella (pp. 0461-0465).
Emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) by municipal solid waste (MSW) incinerators cause concern to the populations living in the vicinity of these facilities. In this study, the health risks of PCDD/F exposure were assessed for adults and children living 500 and 1,000 m from the MSW incinerator. A comparative analysis was performed before (1998) and after (2000) pronounced decreases in PCDD/F air emissions from the stack were noted as a consequence of technical improvements in the facility. At 500 m, total environmental exposure to PCDD/Fs diminished from 5.102 × 10−5 to 1.271 × 10−5 ng I-TEQ/kg/day for adults, and from 8.131 × 10−5 to 2.656 × 10−5 ng I-TEQ/kg/day for children, which means a reduction of 75.1% for adults and 67.3% for children between 1998 and 2000. At 1,000 m, total environmental PCDD/F exposure diminished from 4.087 × 10−5 ng I-TEQ/kg/day in 1998 to 0.995 × 10−5 ng I-TEQ/kg/day in 2000 and from 6.294 × 10−5 ng I-TEQ/kg/day in 1998 to 1.983 × 10−5 ng I-TEQ/kg/day in 2000 for adults and children, respectively. However, these reductions are almost imperceptible compared with the contribution of dietary intake of PCDD/F to total exposure to these contaminants. The present results corroborate that for MSW incinerators with modern technologies, human PCDD/F exposure is mainly due to background contamination.
Results of Multiyear International Interlaboratory Comparison Program for Mercury in Human Hair by U. S. Gill; H. M. Schwartz; L. Bigras (pp. 0466-0472).
Since 1990, Laboratory Services, First Nations and Inuit Health Branch (Health Canada) conducted an interlaboratory comparison program for mercury in human hair. Laboratory Services initiated this program to compare the performance of participating laboratories, analyzing mercury in human hair samples by a variety of analytical methods and instrumental detection techniques. The results of the quality assurance program, which included 31 participants on four continents, are described. Of the participating laboratories, 92% consistently meet QA/QC performance limits for the determination of Hg in human hair. A variety of analytical methods using different digestion and instrumental techniques gave similar results. The most frequently used instrumental techniques were: CV-AA, CV-AFS, and ICP-MS. A summary of results from 24 rounds is provided. The feedback from this program has assisted some laboratories in improving their results and solving some of their analytical problems.
Organochlorine Pesticides and Polychlorinated Biphenyl Residues in Foodstuffs and Human Tissues from China: Status of Contamination, Historical Trend, and Human Dietary Exposure by H. Nakata; M. Kawazoe; K. Arizono; S. Abe; T. Kitano; H. Shimada; W. Li; X. Ding (pp. 0473-0480).
Concentrations of persistent organochlorine pesticides such as DDTs, hexachlorocyclohexanes (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs), were determined in a wide variety of foodstuffs and human tissues collected from Shanghai and its vicinity in China in 2000–2001. Among the organochlorines analyzed, DDT and its metabolites were prominent compounds in most of the foodstuffs. In particular, mussels contained noticeable residues of DDTs (34,000 ng/g lipid weight), which are one to three orders greater than those reported levels in bivalves from other Asian countries. Concentrations of HCHs, CHLs, HCB, and PCBs in foodstuffs were generally low, suggesting small amounts of inputs into the environment. Temporal trends examined by comparing the results of previous studies of organochlorine levels in Chinese foodstuffs in 1970s and 1992 revealed a greater amounts of declines of DDTs and HCHs residues and the average daily intakes during the past 30 years. In contrast, very high concentrations of DDTs and HCHs were detected in human tissues from Shanghai, with the maximum values as high as 19,000 ng/g lipid weight (mean: 7,600 ng/g) and 17,000 ng/g (mean: 7,400 ng/g), respectively. Considering that foodstuffs are a main source of human exposure to contaminants, the greater concentrations of DDTs and HCHs in Chinese people might be due to past extensive usage of these compounds as agricultural pesticides. Continuous monitoring and epidemiological studies of organochlorine pesticides in humans are warranted in China. To our knowledge, this is the first report to present the residue levels of persistent organochlorine pesticides and PCBs in human tissues of China.
Urinary 2,5-Dichlorophenol as Biological Index for p-Dichlorobenzene Exposure in the General Population by T. Yoshida; K. Andoh; M. Fukuhara (pp. 0481-0485).
The relationship between exposure to p-dichlorobenzene (p-DCB) and urinary excretion of 2,5-dichlorophenol (2,5-DCP), the major metabolite of p-DCB, was examined to evaluate the usefulness of the metabolite as a biological index for low-level exposure of p-DCB in the general population. Personal exposure concentrations of p-DCB and concentrations of 2,5-DCP excreted in the urine of 119 adults living in Osaka were determined. Airborne p-DCB was collected for 24 h by passive gas sampling tubes packed with charcoal. The tubes were exchanged every 12 h. The sampling was started immediately after the subject woke up in the morning (7 A.M.). The collected p-DCB was desorbed with toluene and measured using a gas chromatograph with an electron capture detector (GC-ECD). On the other hand, the first morning urine samples were collected at the endpoint of airborne p-DCB sampling (7 A.M. the next morning). The urine samples were hydrolyzed with concentrated sulfuric acid. 2,5-DCP in the hydrolysates was extracted with n-hexane and measured by GC-ECD.Both p-DCB and 2,5-DCP were detected in more than 99% of the air and urine samples, respectively, from the participants. The median of p-DCB exposure concentrations for 24 h was 2.5 ppb, with a maximum concentration of 33.3 ppb. The median of urinary 2,5-DCP concentrations was 0.39 mg/g creatinine, with the maximum concentration of 3.32 mg/g creatinine. The regression line between the urinary 2,5-DCP concentration (y) and the p-DCB exposure concentration (x) was y = 0.080 x + 0.181, with the Pearson correlation coefficient of 0.81 (p < 0.001), demonstrating a strong association between these measurements. Consequently, urinary 2,5-DCP should be suitable as an index for monitoring low-level exposure of p-DCB in the general population.
Metal and Metallothionein Concentrations in Scoter (Melanitta spp.) from the Pacific Northwest of Canada, 1989–1994 by L. Barjaktarovic; J. E. Elliott; A. M. Scheuhammer (pp. 0486-0491).
Eighty-six surf (Melanitta perspicillata) and nine white winged (M. fusca) scoters were collected from 1989–1994 at 11 locations in British Columbia and the Yukon. Their kidney and liver tissues were analyzed for cadmium (Cd), copper (Cu), zinc (Zn), and metallothionein (MT) concentrations. Individual kidney Cd values ranged from 2.4 μg/g dry weight (DW) in birds from northern Vancouver Island to 390.2 μg/g (DW) in birds from the Queen Charlotte Islands, which is in the range of values potentially associated with kidney damage. Birds from the Queen Charlotte Islands also had high kidney Zn concentrations, which were significantly higher than values in birds from Naniamo and Westham Island on the south coast of BC. Cd values were significantly (p < 0.001) correlated with both Zn and MT concentrations in kidney tissue (r = 0.66 and 0.62, respectively). Male surf scoters had significantly higher kidney Cd and Zn levels than females, with mean Cd values of 47.3 and 19.7 μg/g DW (p < 0.002) for males and females, respectively. Mean Zn values were 120.8 and 108.0 μg/g DW (p < 0.05) for males and females, respectively. However, no sex differences were observed for either Cu or MT concentrations in kidney tissue. Individual MT values ranged from 2.7 to 416.8 μg/g wet weight (WW). Individual kidney Cu values ranged from 15.1 to 48.4 μg/g DW for both sexes. Kidney and liver Cd concentrations were significantly correlated (r = 0.90, p < 0.05) with kidney levels almost always higher than liver values. Although Cd accumulation by the Skidegate scoters was high, comparable tissue Cd values have been documented in other seabirds collected from the same general area, indicating elevated Cd concentrations in marine food chains around the Queen Charlotte Islands (Haida Gwaii) region of the Pacific coast.
Accumulation and Regulation of Zinc in Daphnia magna: Links with Homeostasis and Toxicity by B. T. A. Muyssen; C. R. Janssen (pp. 0492-0496).
Zinc accumulation in Daphnia magna was investigated, and the results were linked to the previously established optimal concentration range for zinc and D. magna. It was observed that organisms cultured in this optimal range (300–600 μg Zn/L) contained 212 ± 57 to 254 ± 79 μg Zn/g dry weight. Lower and higher zinc contents were obtained after acclimation to previously established culture concentrations inducing deficiency and toxicity, respectively. The calculation of bioconcentration factors indicated that zinc was actively regulated, at least up to a concentration of 600 μg Zn/L. Zinc uptake and elimination are rapid processes; major increases and decreases in body content occurred within 1 day. Zinc concentrations in daphnids exposed to 600 μg Zn/L fluctuated with 2- to 3-day intervals, suggesting a role of molting in the regulation and elimination of zinc.
Quantitative Biomonitoring of PAHs Using the Barnes Mussel (Elliptio complanata) by S. B. Gewurtz; K. G. Drouillard; R. Lazar; G. D. Haffner (pp. 0497-0504).
The elimination rate constants (k 2) of nine polycyclic aromatic hydrocarbons (PAHs) were examined for the freshwater mussel Elliptio complanata. The concentrations of fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and indeno[1,2,3-c,d]pyrene revealed a significant inverse relationship with time and their k 2 values ranged from 0.10 to 0.22 day−1. The k 2 values of these significantly cleared PAHs were similar to k 2 values observed for nonmetabolized organochlorines in mussels previously reported in the literature. The inverse relationship between k 2 and K ow provides evidence that the nine PAHs were being passively eliminated from the mussels and that they can be used to calibrate the mussel as a quantitative biomonitor. A general expression relating elimination rate constants and chemical K ow is derived for hydrophobic contaminants in E. complanata. The k 2 versus log K ow regression equation for mussels developed herein was similar to other studies documenting the elimination of PCBs and PAHs in a number of bivalve species.