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Archives of Environmental Contamination and Toxicology (v.61, #3)
Cloud Point Extraction With Triton X-114 for Separation of Metsulfuron-Methyl, Chlorsulfuron, and Bensulfuron-Methyl From Water, Soil, and Rice and Analysis by High-Performance Liquid Chromatography by Yan Jiao Wu; Xu Wei Fu; Hong Yang (pp. 359-367).
A new and efficient analytic methodology based on cloud point extraction (CPE) was developed for determination of pesticide residues of metsulfuron-methyl (MSM), chlorsulfuron (CS), and bensulfuron-methyl (BSM) in water, soil, and rice grain by high-performance liquid chromatography (HPLC). Multiple experimental conditions that affected CPE efficiency―including surfactant type and concentration, equilibration temperature and duration, ionic strength, and solution pH were identified. CPE conditions were optimized as follows: 1.5% Triton X-114 (w/v), 12% Na2SO4 (w/v) solution (pH 2.0), and heat-assisted at 50°C for 15 min. The calibration curves for all analytes were linear, ranging from 0.05 to 4.0 mg L−1, with the correlation coefficients >0.9995 by HPLC-ultraviolet detector and were linear, ranging from 0.004 to 2.0 mg L−1, with correlation coefficients >0.9983 by CPE-HPLC. The average recoveries at the three spiked levels using CPE ranged from 86.0% to 94.5% for water samples with relative SDs (RSDs) of 0.4% to approximately 7.8%; from 85.6% to 94.8% for soil samples with RSDs of 1.2% to approximately 9.5%; and from 81.9% to 91.3% for rice samples with RSDs of 1.7% to approximately 5.8%. The proposed CPE-HPLC method can be successfully used to analyze MSM, CS, and BSM residues from contaminated water, soil, and rice grain samples.
A Comparative Toxicity Assessment of Materials Used in Aquatic Construction by Benoit A. Lalonde; William Ernst; Gary Julien; Paula Jackman; Ken Doe; Rebecca Schaefer (pp. 368-375).
Comparative toxicity testing was performed on selected materials that may be used in aquatic construction projects. The tests were conducted on the following materials: (1) untreated wood species (hemlock [Tsuga ssp], Western red cedar (Thuja plicata), red oak [Quercus rubra], Douglas fir [Pseudotsuga menziesii], red pine [Pinus resinosa], and tamarack [Larix ssp]); (2) plastic wood; (3) Ecothermo wood hemlock stakes treated with preservatives (e.g., chromated copper arsenate [CCA], creosote, alkaline copper quaternary [ACQ], zinc naphthenate, copper naphthenate, and Lifetime Wood Treatment); (4) epoxy-coated steel; (5) hot-rolled steel; (6) zinc-coated steel; and (7) concrete. Those materials were used in acute lethality tests with rainbow trout, Daphnia magna, Vibrio fischeri and threespine stickleback. The results indicated the following general ranking of the materials (from the lowest to highest LC50 values); ACQ > creosote > zinc naphthenate > copper naphthenate > CCA (treated at 22.4 kg/m3) > concrete > red pine > western red cedar > red oak > zinc-coated steel > epoxy-coated steel > CCA (6.4 kg/m3). Furthermore, the toxicity results indicated that plastic wood, certain untreated wood species (hemlock, tamarack, Douglas fir, and red oak), hot-rolled steel, Ecothermo wood, and wood treated with Lifetime Wood Treatment were generally nontoxic to the test species.
Relating Injury to the Forest Ecosystem Near Palmerton, PA, to Zinc Contamination From Smelting by W. Nelson Beyer; Cairn Krafft; Stephen Klassen; Carrie E. Green; Rufus L. Chaney (pp. 376-388).
The forest on Blue Mountain, near Lehigh Gap, has been injured by emissions from two historical zinc (Zn) smelters in Palmerton, PA, located at the northern base of the mountain. The uppermost mineral soil and lower litter from sites along a transect, just south of the ridgetop, contained from 64 to 4400 mg/kg Zn. We measured forest metrics at 15 sampling sites to ascertain how forest structure, species composition and regeneration are related to soil concentrations of Zn, the probable principal cause of the injury. Understanding how ecotoxicological injury is related to soil Zn concentrations helps us quantify the extent of injury to the ecosystem on Blue Mountain as well as to generalize to other sites. The sum of canopy closure and shrub cover, suggested as a broadly inclusive measure of forest structure, was decreased to half at approximately 2060 mg/kg Zn (102 mg/kg Sr(N03)2-extractable Zn). Tree-seedling density was decreased by 80% (from 10.5/m2 to 2.1/m2) at a much lower concentration: 1080 mg/kg Zn (59 mg/kg Sr(N03)2-extractable Zn). Changes in species composition and richness were not as useful for quantifying injury to the forest. Phytotoxicity, desiccation from exposure, and a gypsy moth infestation combined to form a barren area on the ridgetop. Liming the strongly acid Hazleton soils at the sites would partially ameliorate the observed phytotoxicity and should be considered in planning restoration.
Statistical Evaluation of Environmental Contamination, Distribution and Source Assessment of Heavy Metals (Aluminum, Arsenic, Cadmium, and Mercury) in Some Lagoons and an Estuary Along the Coastal Belt of Ghana by C. K. Adokoh; E. A. Obodai; D. K. Essumang; Y. Serfor-Armah; B. J. B. Nyarko; A. Asabere-Ameyaw (pp. 389-400).
An environmental pollution investigation was carried out to determine the concentrations of aluminum (Al), arsenic (As), cadmium (Cd), and mercury (Hg) (heavy metals) in the surface water and river water bed sediments of lagoons and estuaries along the coastal belt of Ghana. The study assessed the environmental pollution situation and evaluated their sources and distribution of these metals. The total concentrations of Al, As, Cd, and Hg were determined by the neutron activation analysis technique. Water and sediment samples were collected from the Benya, Fosu, and Narkwa lagoons in the Central Region and from the Pra estuary in the western part of Ghana. Some indices, such as contamination factor, pollution-load index, contamination degree, and geoaccumulation index, were used to assess eco-environmental quality of the sampling sites. The analysis indicated that the Fosu lagoon was fairly polluted with Cd. The investigation indicated a highly localized distribution pattern closely associated with the two pollution sources (garbage/solid waste dumps and industrial activities) along the coastal belt. The resulting environmental deterioration required a concerted evaluative effort by all stakeholders.
Antioxidant Response of Three Tillandsia Species Transplanted to Urban, Agricultural, and Industrial Areas by Gonzalo M. A. Bermudez; María Luisa Pignata (pp. 401-413).
To evaluate the physiological response of Tillandsia capillaris Ruiz & Pav. f. capillaris, T. recurvata L., and T. tricholepis Baker to different air pollution sources, epiphyte samples were collected from a noncontaminated area in the province of Córdoba (Argentina) and transplanted to a control site as well as three areas categorized according to the presence of agricultural, urban, and industrial (metallurgical and metal-mechanical) emission sources. A foliar damage index (FDI) was calculated with the physiological parameters chlorophyll a, chlorophyll b, malondialdehyde (MDA), hydroperoxyconjugated dienes, sulfur (S) content, and dry weight-to-fresh weight ratio. In addition, electrical conductivity (E-cond), relative water content (RWC), dehydration kinetics (Kin-H2O), total phenols (T-phen), soluble proteins (S-prot), and activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase were determined. The parameters E-cond, FDI, SOD, RWC, and Kin-H2O can serve as suitable indicators of agricultural air pollution for T. tricholepis and T. capillaris, and CAT, Kin-H2O, and SOD can do the same for T. recurvata. In addition, MDA, T-phen, and S-prot proved to be appropriate indicators of urban pollution for T. recurvata. Moreover, FDI, E-cond, and SOD for T. recurvata and MDA for T. tricholepis, respectively, could be used to detect deleterious effects of industrial air pollution.
An Assessment of Three Harpacticoid Copepod Species for Use in Ecotoxicological Testing by Daniel J. Ward; Victor Perez-Landa; David A. Spadaro; Stuart L. Simpson; Dianne F. Jolley (pp. 414-425).
The relatively short life cycles of harpacticoid copepods makes them appropriate animals for use in tests that rapidly assess the acute, sublethal, or chronic effects of sediment contaminants. In this study, four harpacticoid copepod species (Nitocra spinipes, Tisbe tenuimana, Robertgurneya hopkinsi, and Halectinosoma sp.) were isolated from clean marine sediments, and procedures for laboratory culturing were developed. Halectinosoma sp. was abandoned due to handling difficulties. For the remaining species, the influence of food type and quantity on life-cycle progression was assessed. A mixed diet, comprising two species of algae (Tetraselmis sp. and Isochrysis sp.) and fish food (Sera Micron) was found to maintain healthy cultures and was fed during laboratory tests. Water-only exposure to dissolved copper (Cu) showed that the times (range) required to cause 50% lethality (LT50) were 24 (22–27) h at 50 μg Cu/l for T. tenuimana; 114 (100–131) and 36 (32–40) h for 200 and 400 μg Cu/l, respectively, for N. spinipes; and 119 (71–201) and 25 (18–33) h for 200 and 400 μg Cu/l, respectively, for R. hopkinsi. 96-h LC50 (concentration causing 50% lethality) were also determined for adult N. spinipes exposed to cadmium, copper, zinc, ammonia, and phenol. A ranking system was generated based on the ease handling and culturing, rate of maturity, food selectivity and sensitivity to Cu. From this ranking, N. spinipes was determined to be the most suitable species for use in developing sediment-toxicity tests. The measurement of total reproductive output of N. spinipes during 10-day exposure to whole sediment was found to provide a useful end point for assessing the effects of sediment contamination.
Investigating Arsenic Bioavailability and Bioaccumulation by the Freshwater Oligochaete Lumbriculus variegatus by Marcelo Nasi; María N. Piol; Cecilia Di Risio; Noemí R. Verrengia Guerrero (pp. 426-434).
The complex and variable composition of natural sediments makes it difficult to predict the bioavailability and bioaccumulation of sediment-bound contaminants. Several approaches, including an experimental model using artificial particles as analogues for natural sediments, have been proposed to overcome this problem. For this work, we applied this experimental device to investigate the uptake and bioaccumulation of AsIII by the freshwater oligochaete Lumbriculus variegatus. Five different particle systems were selected, and particle–water partition coefficients for AsIII were calculated. The influence of different concentrations of commercial humic acids was also investigated, but this material had no effect on bioaccumulation. In the presence of particulate matter, the bioaccumulation of AsIII by the oligochaetes did not depend solely on the levels of chemical dissolved but also on the amount sorbed onto the particles and the strength of that binding. This study confirms that the use of artificial particles may be a suitable experimental model for understanding the possible interactions that may occur between contaminants and particulate matter. In addition, it was found that the most hydrophobic resin induced an increase in arsenic bioavailability, leading to the highest bioaccumulation to L. variegatus compared with animals that were exposed to water only.
Acute Exposure of Arsenic Tri-oxide Produces Hyperglycemia in both Sexes of an Indian Teleost, Clarias batrachus (Linn.) by Bibha Kumari; Jawaid Ahsan (pp. 435-442).
The present investigation has been conducted to study of the effect of acute exposure of sublethal doses of arsenic tri-oxide (As2O3) on blood glucose level in an Indian teleost, Clarias batrachus, during their post-breeding season (October to January). The effect was correlated with the sex and doses used with time. Acute exposure of As2O3 of 5, 10 and 15 mg/l for six consecutive days (i.e., 144 h) has been conducted on both sexes of C. batrachus. During the present investigation, it was noticed that the females were more reactive to arsenic in producing hyperglycemia compared to their male counterparts. The difference between males and females to produce hyperglycemia on exposure to arsenic appears to be dose dependent, as lower doses of 5 and 10 mg/l exhibit less difference between the two sexes compared to the highest dose order of 15 mg/l. After 96 h of treatment, a normoglycemic condition was observed in both sexes. However, no significant differences in average normal blood glucose levels were noticed in male and female C. batrachus during the post-breeding season.
Effect of Yerbimat Herbicide on Lipid Peroxidation, Catalase Activity, and Histological Damage in Gills and Liver of the Freshwater Fish Goodea Atripinnis by Esperanza Ortiz-Ordoñez; Esther Uría-Galicia; Ricardo Arturo Ruiz-Picos; Angela Georgina Sánchez Duran; Yoseline Hernández Trejo; Jacinto Elías Sedeño-Díaz; Eugenia López-López (pp. 443-452).
The use of herbicides for agricultural and aquatic weed control has increased worldwide. These substances are potentially toxic pollutants because they induce the production of reactive oxygen species for biological systems and exert oxidative stress in nontarget organisms living in the treated aquatic systems. Recent evidence suggests differences in the toxicity of glyphosate in the form of an active ingredient compared to the toxicity of glyphosate in combination with surfactants, such as those found in commercial formulations. In Mexico, one of the most widely used glyphosate-based herbicides is Yerbimat, which has agricultural as well as aquatic weed control applications. However, there are no aquatic toxicity data, particularly regarding native fish. Therefore, we determined the acute toxicity of commercial-formulation Yerbimat in a static bioassay at 96 h (LC50). We also determined its toxicity at 96 h in sublethal concentrations to assess the lipid peroxidation levels (LPX), catalase activity, hepatic glycogen content, and histological damage in the liver and gills of the fish Goodea atripinnis associated with chronic exposure (75 days). The LC50 was 38.95 ± 0.33 mg/L. The results of the short-term exposure study indicate that Yerbimat can potentially induce oxidative stress in G. atripinnis, because LPX was increased in the gills and liver. Catalase activity was reduced in the gills but increased in the liver, whereas hepatic glycogen was depleted. Chronic exposure was associated with histopathological damage in the gills and liver, some of which was irreversible. Yerbimat represents a potential risk for aquatic biota; therefore, we recommend that its application be carefully considered.
Biochemical Stress Responses in Tissues of the Cichlid Fish Cichlasoma dimerus Exposed to a Commercial Formulation of Endosulfan by Carla Bacchetta; Jimena Cazenave; María Julieta Parma; Gabriela Fiorenza Biancucci (pp. 453-460).
Median lethal concentration (LC50) and sublethal effects of the commercial endosulfan formulation Zebra Ciagro® on the fish Cichlasoma dimerus were studied. The 96-h LC50 was estimated as 17.7 μg/L. In order to investigate sublethal effects, fish were exposed to 25% and 50% LC1 (3.4 and 6.8 μg/L, respectively). Endosulfan (ED) significantly increased the hemoglobin concentration and white blood cell count after 96 h. Differential leukocytes count was also altered, due to an increase in the percentage of neutrophils in exposed fish. The hepatopancreatic tissue of fish under ED treatment showed a decrease in aspartate aminotransferase and alanine aminotransferase and an increase in alkaline phosphatase. Lipid peroxidation levels in the 6.8-μg/L ED-containing group were higher than those in control fish for all organs tested (gills, hepatopancreas, and brain).
Elevated Levels of Metals and Organic Pollutants in Fish and Clams in the Cape Fear River Watershed by Michael A. Mallin; Matthew R. McIver; Michael Fulton; Ed Wirth (pp. 461-471).
A study was performed in 2003 to 2004 to assess metal and organic contaminant concentrations at three areas in the lower Cape Fear River system, North Carolina, United States. Sites examined were Livingston Creek along the mainstem of the Cape Fear River near Riegelwood, Six Runs Creek in the Black River Basin, and Rockfish Creek in the Northeast Cape Fear River basin. The results of the investigation showed that levels of metals and organic pollutants in the sediments were lower than limits considered harmful to aquatic life. However, results of fish (adult bowfin) tissue analyses showed that concentrations of arsenic (As), cadmium (Cd), mercury (Hg), selenium (Se), and now-banned polychlorinated biphenyls (PCBs), and the pesticide dieldrin were higher than levels considered safe for human consumption by the United States Environmental Protection Agency and the North Carolina Health Director’s Office. Fish tissue concentrations of Hg, Se, and PCBs were also higher than concentrations determined by researchers to be detrimental either to the health of the fish themselves or their avian and mammalian predators. Due to the rural nature of two of the sites, increased concentrations of As, Cd, Se, and PCBs in fish tissue were unexpected. The likely reason the levels are increased in fish and some clams but not in sediments is that these pollutants are biomagnified in the food chain. These pollutants will also biomagnify in humans. In these rural areas there is subsistence fishing by low-income families; thus, increased fish tissue metals and toxicant concentrations may present a direct threat to human health.
Trace Metal Concentrations in Sediments and Fish in the Vicinity of Ash Lagoon Discharges from Coal-Combustion Plants in New Brunswick and Nova Scotia, Canada by Benoit A. Lalonde; William Ernst; Fernand Comeau (pp. 472-481).
Metals that originate from coal-combustion residue (ash) deposited in water-filled lagoons are eventually released into the environment. This study measured metal concentrations in sediment and fish obtained in the vicinity of two coal-combustion ash-lagoon outfalls on the East River (Nova Scotia) and Grand Lake (New Brunswick), Canada. Of the 34 metals analysed, this study demonstrated that sediment in the immediate vicinity of the ash lagoon discharge in New Brunswick had statistically significant greater concentrations of thallium, arsenic, and antimony than did the sediment obtained from background areas. Tissue arsenic concentrations were increased in fish obtained near the lagoon discharge in New Brunswick but not statistically greater than that of fish obtained from background areas. Neither sediment nor fish obtained near the ash-lagoon discharge in Nova Scotia had significantly greater concentrations of any of the metals measured.
Oxidative Stress and Genotoxicity Biomarker Responses in Grey Mullet (Mugil cephalus) From a Polluted Environment in Saronikos Gulf, Greece by Catherine Tsangaris; Maya Vergolyas; Eleni Fountoulaki; Konstantin Nizheradze (pp. 482-490).
This study aimed to assess oxidative stress and genotoxicity biomarkers in grey mullet Mugil cephalus from a site receiving discharges from industrial and harbor activities and a reference site in Saronikos Gulf, Greece. Cellular antioxidant defenses, i.e., antioxidant enzyme activities (catalase, selenium [Se]-dependent glutathione peroxidase, glutathione-S-transferase) and oxidative damage, i.e., lipid peroxidation (measured as thiobarbituric acid reactive substances) were used as biomarkers of oxidative stress. The micronucleus test was used for evaluation of chromosome damage, and the frequency of cells with double nuclei was used as an indication of damage to cell divisions. Antioxidant enzyme activities were lower in fish from the polluted site compared with fish from the reference site, suggesting deficiency of the antioxidant system to compensate for oxidative stress. This is further supported by the higher lipid peroxidation levels in fish from the polluted site, which represent oxidative damage. Micronuclei and double-nuclei frequencies were higher in fish from the polluted site compared with fish from the reference site, indicating genotoxic effects. Correlations between biomarkers suggest that observed effects were due to contaminants exhibiting oxidative stress potential that can also induce genotoxicity. Results suggest that the selected biomarkers in M. cephalus are useful for the assessment of pollution impacts in coastal environments influenced by multiple pollution sources.
Mercury Biomagnification in the Aquaculture Pond Ecosystem in the Pearl River Delta by Zhang Cheng; Peng Liang; Ding-Ding Shao; Sheng-Chun Wu; Xiang-Ping Nie; Kun-Ci Chen; Kai-Bin Li; Ming-Hung Wong (pp. 491-499).
This is the first study to investigate the rate of mercury (Hg) biomagnification in the aquaculture pond ecosystem of the Pearl River Delta (PRD), China, by analyzing total mercury (THg) and methyl mercury (MeHg) concentrations in various species of fish at different trophic levels (TLs). Species representing a gradient of trophic positions in the aquaculture pond food chains were chosen for analyzing THg and MeHg concentrations. In this study, there were two kinds of the aquaculture pond food chains: (1) omnivorous (fish feeds, zooplankton, grass carp [Ctenopharyngodon idellus], and bighead carp [Aristichthys nobilis]) and (2) predatory (zooplankton, mud carp [Cirrhina molitorella], and mandarin fish [Siniperca kneri]). Bighead carp and mandarin fish had the highest MeHg and THg concentrations, i.e., an order of magnitude higher than other species, in their respective food chains. More than 90% of the THg concentrations detected in bighead carp, mandarin fish, and mud carp were in the methylated form. In this study, %MeHg increased with TLs and MeHg concentrations, reflecting that MeHg is the dominant chemical species of Hg accumulated in higher concentrations in biota, especially biota associated with higher TLs in the food chains. The trophic magnification factors were 2.32 and 2.60 for MeHg and 1.94 and 2.03 for THg in omnivorous and predatory food chains, respectively, in PRD. Hg concentrations in fish tissue correlated to Hg levels in the ambient environment, and sediment seemed to be the major source for Hg accumulated in fish. In addition, feeding habit also affected Hg accumulation in different fish species. Four significant linear relationships were obtained between log-THg and δ15N and between log-MeHg and δ15N. The slope of the regression equations, as biomagnification power, was smaller in magnitude compared with those reported for temperate and arctic marine and freshwater ecosystems, indicating that THg and MeHg biomagnifications were lower in this PRD subtropical aquaculture pond ecosystem. This was probably due to low Hg bioavailability at lower TLs as well as individual feeding behavior of fish.
Simultaneous Effects of Lead and Cadmium on Primary Cultures of Rat Proximal Tubular Cells: Interaction of Apoptosis and Oxidative Stress by Lin Wang; Heng Wang; Jingui Li; Dawei Chen; Zongping Liu (pp. 500-511).
The combined effects of lead (Pb) and cadmium (Cd) on primary cultures of rat proximal tubular (rPT) cells were studied. These cells were either treated with Pb acetate (0.5 and 1 μM) alone, Cd acetate (2.5 and 5 μM) alone, or a combination of Pb and Cd acetate, and then joint cytotoxicity was evaluated. The results showed that the combination of these two metals decreased cell viability and increased the number of apoptotic and necrotic cells and lactate dehydrogenase release synergistically. Simultaneously, increased intracellular reactive oxygen species, malondialdehyde, and calcium levels and decreased mitochondrial membrane potential, intracellular acidification, and inhibition of Na+, K+-, and Ca2+-ATPase activities were shown during the exposure. In addition, apoptotic morphological changes induced by these treatments in rPT cells were demonstrated by Hoechst 33258 staining. The apoptosis was markedly prevented by N-acetyl-l-cysteine, whereas necrosis was not affected. In summary, there was a synergistic cytototic effect of Pb combined with Cd on rPT cells. Cell death induced by Pb–Cd mixture was mediated by an apoptotic and a necrotic mechanism. Apoptotic death was the chief mechanism. Changes of intracellular events were intimately correlated with both oxidative stress and mitochondrial dysfunction, which promoted the development of apoptosis.
Assessment of the Exposure to Elements from Silver Jewelry by Hair Mineral Analysis by Katarzyna Chojnacka; Izabela Michalak; Agnieszka Zielińska; Henryk Górecki (pp. 512-520).
The aim of the present article was to assess the effect of wearing silver jewelry on mineral composition of human scalp hair. To investigate the possible effect of gender, a group of females and males was distinguished. Subjects, who declared in the questionnaire wearing silver jewelry, constituted 55% of the whole population. It was found that individuals wearing jewelry had increased levels of Ag (~ 3 times), Ba (30%), Ca (33%), La (40%), Li (25%), and Zn (27%) in hair and lowered level of: Al (34%), K (79%), and Na (32.5%) in comparison with the group that did not wear jewelry. Those differences were statistically significant. Lower levels of K and Na in hair of subjects wearing jewelry was probably related with an antagonism between Ag-K and Ag-Na found in the present work. Analyzing the effect of two grouping variables—gender and wearing silver jewelry—on hair composition, it was observed that statistically significant differences were determined for the following elements: As, Ba, Ca, and Se. Female hair contained two times more Ca, four times Ba, 36% less As, and five times less Se. It was found that 34% of the population wearing silver jewelry had higher Ag content in hair than the upper value of the reference range (0.567 mg/kg) determined for subjects who did not wear jewelry. Ag and other metals (especially Cu and Zn) from jewelry could be absorbed through the skin and therefore hair mineral analysis is useful in the assessment of this exposure. The study was carried out on Poles, among which silver jewelry is particularly popular. The population can be thus considered as exposed.
δ-Aminolevulinic Acid Dehydratase Single Nucleotide Polymorphism 2 and Peptide Transporter 2*2 Haplotype May Differentially Mediate Lead Exposure in Male Children by Christina Sobin; Natali Parisi; Tanner Schaub; Marisela Gutierrez; Alma X. Ortega (pp. 521-529).
Child low-level lead (Pb) exposure is an unresolved public health problem and an unaddressed child health disparity. Particularly in cases of low-level exposure, source removal can be impossible to accomplish, and the only practical strategy for reducing risk may be primary prevention. Genetic biomarkers of increased neurotoxic risk could help to identify small subgroups of children for early intervention. Previous studies have suggested that, by way of a distinct mechanism, δ-aminolevulinic acid dehydratase single nucleotide polymorphism 2 (ALAD2) and/or peptide transporter 2*2 haplotype (hPEPT2*2) increase Pb blood burden in children. Studies have not yet examined whether sex mediates the effects of genotype on blood Pb burden. Also, previous studies have not included blood iron (Fe) level in their analyses. Blood and cheek cell samples were obtained from 306 minority children, ages 5.1 to 12.9 years. 208Pb and 56Fe levels were determined with inductively coupled plasma–mass spectrometry. General linear model analyses were used to examine differences in Pb blood burden by genotype and sex while controlling for blood Fe level. The sample geometric mean Pb level was 2.75 μg/dl. Pb blood burden was differentially higher in ALAD2 heterozygous boys and hPEPT2*2 homozygous boys. These results suggest that the effect of ALAD2 and hPEPT2*2 on Pb blood burden may be sexually dimorphic. ALAD2 and hPEPT2*2 may be novel biomarkers of health and mental health risks in male children exposed to low levels of Pb.
Indoor Air Polychlorinated Biphenyl Concentrations in Three Communities Along the Upper Hudson River, New York by Lloyd R. Wilson; Patrick M. Palmer; Erin E. Belanger; Michael R. Cayo; Lorie A. Durocher; Syni-An A. Hwang; Edward F. Fitzgerald (pp. 530-538).
Indoor air polychlorinated biphenyl (PCB) concentrations were measured in upstate New York as part of a nonoccupational exposure investigation. The adjacent study communities contain numerous sites of current and former PCB contamination, including two capacitor-manufacturing facilities. Indoor air PCB concentrations in the study area homes were not significantly different than in the comparison area homes. Total PCB concentrations in the study area homes ranged from 0.3 to 114.3 ng/m3 (median 7.9). For the comparison area homes, concentrations ranged from 0.3 to 233.3 ng/m3 (median 6.8). No correlations were found between PCB concentrations in indoor and outdoor air, with indoor concentrations generally 20 times higher than outdoor concentrations. Of the home characteristics cataloged, the presence of fluorescent lights was significantly associated with total PCB concentration in the study area only. The indoor PCB concentrations measured in this study are similar to those in other communities with known PCB-contaminated sites and similar to levels reported in other locations from the northeastern United States.