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Archives of Environmental Contamination and Toxicology (v.49, #2)
The Temporal and Spatial Variations of Acid Aerosols in the GeothermalArea of Metropolitan Taipei, Taiwan by I-Fang Mao; Li-Ting Chen; Yen-Neng Wang; Sheng-Fen Yang; Huei-Chen Chen; Mei-Lien Chen (pp. 141-149).
This study involved sampling over 1 year of data on exposure to acid aerosols in the geothermal area of metropolitan Taipei. The temporal and spatial variations of the concentrations of acid aerosols were assessed by sampling at three sites: A, B, and C. Results indicate that the SO2 concentrations lead the concentrations of other acid aerosols at site C because two active fumaroles surround this site. The mean SO2 concentrations at sites A, B, and C were 2.4, 2.4, and 6.2 ppb. Previous studies have found that H2S levels were highest at site C. However, the SO4−2 and H+ concentrations among the three sites were similar. The mean aerosol SO4−2 concentrations were 7.0, 5.7, and 5.7 μg m−3 at sites A, B, and C, respectively; their H+ concentrations were 5.5, 4.2, and 5.4 nmolm−3. No seasonal variations are observed for most of the acid aerosols in the geothermal area except that the types of hot spring affect the SO4−2 concentration nearby. The different seasonal fluctuation among the sites reflect the determinant of SO4−2 emission from different geothermal sources. Sulfur-rich aerosols and some SO2 emitted from geothermal sources are obvious. The predominance of nitrogen-containing gases (sum of NO2 + HNO2 + HNO3) over SO2 indicates the importance of the anthropogenic origin of emissions. The effect of multiple exposures to sulfur-rich aerosol (including H2S, SO2, and SO4−2), H+, and nitrogen-containing aerosols on the health of nearby residents warrants concern.
Detoxification of Cyanide by Woody Plants by Xiaozhang Yu; Puhua Zhou; Yunda Liu; Hao Hu (pp. 150-154).
Vascular plants possess an enzyme system that detoxifies cyanide by converting it to the amino acid asparagine. This paper examines the potential of three woody plants from the Salicaceae family to degrade cyanide. Pre-rooted trees were grown in carefully designed bioreactors with aqueous solution spiked with potassium cyanide at 23.0 ± 1°C for a maximum of 144 h. Cyanide concentrations ranged from 0.95 to 1.15 CN mg/L. Cyanide in water and in plant tissues was analyzed spectrophotometrically. Results from the investigation indicated that significant reduction of aqueous cyanide was found during the presence of plants in all treatments. Little amounts of applied cyanide were detected in the tissues of plants, mainly in roots and bottom stem. Cyanide remaining in tissues varied with the species of plants, despite similar periods of exposure. The data also indicated that photolysis, hydrolysis, and microbial degradation were not occurring and that volatilization was minimal. In conclusion, transport and metabolism of cyanide in plants is most likely.
Evaluation of Ionic Contribution to the Toxicity of a Coal-Mine Effluent Using Ceriodaphnia dubia by A J Kennedy; D S Cherry; C E Zipper (pp. 155-162).
The United States Environmental Protection Agency has defined national in-stream water-quality criteria (WQC) for 157 pollutants. No WQC to protect aquatic life exist for total dissolved solids (TDS). Some water-treatment processes (e.g., pH modifications) discharge wastewaters of potentially adverse TDS into freshwater systems. Strong correlations between specific conductivity, a TDS surrogate, and several biotic indices in a previous study suggested that TDS caused by a coal-mine effluent was the primary stressor. Further acute and chronic testing in the current study with Ceriodaphnia dubia in laboratory-manipulated media indicated that the majority of the effluent toxicity could be attributed to the most abundant ions in the discharge, sodium (1952 mg/L) and/or sulfate (3672 mg/L), although the hardness of the effluent (792 ± 43 mg/L as CaCO3) ameliorated some toxicity. Based on laboratory testing of several effluent-mimicking media, sodium- and sulfate-dominated TDS was acutely toxic at approximately 7000 μS/cm (5143 mg TDS/L), and chronic toxicity occurred at approximately 3200 μS/cm (2331 mg TDS/L). At a lower hardness (88 mg/L as CaCO3), acute and chronic toxicity end-points were decreased to approximately 5000 μS/cm (3663 mg TDS/L) and approximately 2000 μS/cm (1443 mg TDS/L), respectively. Point-source discharges causing in-stream TDS concentrations to exceed these levels may risk impairment to aquatic life.
A Short-Term Sublethal In Situ Sediment Assay with Chironomus riparius Based on Postexposure Feeding by S Soares; I Cativa; M Moreira-Santos; A M V M Soares; R Ribeiro (pp. 163-172).
A short-term, sublethal, and cost-effective in situ sediment toxicity assay for routine assessments with the midge Chironomus riparius Meigen, based on postexposure feeding, was developed and evaluated. An inexpensive and easy-to-use assay chamber was designed. A sediment toxicity assay was successfully performed at a lentic system impacted by acid mine drainage, at sites with different types of sediment. It consisted of a 48-h exposure period followed by a 1-h postexposure feeding during which the larvae were fed on Artemia franciscana nauplii. Methodologies for feeding quantification of fourth-instar larvae (10-d old) were first developed and optimized under laboratory conditions. A. franciscana nauplii were shown to be more suited than fish flake food for postexposure feeding quantification, allowing higher precision and cost-effectiveness. It also required a shorter postexposure feeding period, thus minimizing the chances for an eventual organism physiological recovery from toxicant exposure. The influence of several environmental conditions during exposure on postexposure feeding was also evaluated: temperature, dissolved oxygen, pH, salinity, hardness, substrate, humic acids, light, and food availability. Only temperature was found to significantly influence postexposure feeding rates; exposure at 5°C led to reduced feeding activity compared to 30°C. Recovery rates of 87% were obtained after the 48-h field exposure at all sites (except site R2). A statistically significant postexposure feeding depression was observed at the three sites impacted by acid mine drainage. Therefore, the proposed short-term in situ assay is a potentially useful tool to assess sediment sublethal toxicity on a routine basis.
Joint Toxicity of Triazine Herbicides and Organophosphate Insecticides to the Midge Chironomus tentans by L. J. Schuler; A. J. Trimble; J. B. Belden; M. J. Lydy (pp. 173-177).
A series of recent studies demonstrated that the triazine herbicide atrazine, although not itself acutely toxic, potentiated the toxicity of certain organophosphate insecticides (OPs) to the midge Chironomus tentans. In the current study, a series of triazine herbicides and triazine herbicide degradation products were tested to determine if other triazines potentiate OP toxicity to midges. Chlorpyrifos and diazinon were the OPs tested. Toxicity tests were conducted using a factorial design and analysis of variance to statistically determine if each triazine had an effect on expected toxicity. Log-probit procedures were also used to evaluate the magnitude of change in median effective concentration (EC50) values during coexposure with each triazine. All of the triazine herbicides tested (atrazine, simazine, cyanazine, and hexazinone) were capable of potentiating the toxicity of the OPs, whereas the degradation products (s-triazine, deethylatrazine, and deisopropylatrazine) had less effect. In most cases, a triazine concentration of 100 μg/L was necessary to significantly increase OP toxicity, and higher concentrations of triazine caused a greater degree of potentiation. Changes in EC50 values ranged from no change to a 2.5-fold increase in toxicity. Generally, EC50 values changed by less than a factor of 2, indicating that the effect may be of limited concern in regard to future risk assessments of OPs.
Assessment of PCBs and PCDD/Fs Along the Chinese Bohai Sea Coastline Using Mollusks as Bioindicators by X Zhao; M Zheng; L Liang; Q Zhang; Y Wang; G Jiang (pp. 178-185).
Mollusk samples such as bivalves and gastropods were collected from eight sampling sites along Bohai Sea coastline from northeastern China. The samples were analyzed for polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC-HRMS) to elucidate bioaccumulation of persistent organic pollutants in benthon. Residue levels of ΣPCBs and ΣPCDD/Fs were in the ranges of 66.1 to 583.6 ng/g and 0.9 to 15317 pg/g on a lipid-weight basis, respectively, The pollution source was identified using principal component analysis (PCA) in some coastal areas. It indicated that the typical pollution sources were characterized by PCB3, which was one Chinese technical product of PCBs. PCA also revealed the similarity patterns of PCBs between identical species collected from the different sites. The higher gastropod PCB concentrations were related to a former capacitor factory and the paint factories in some coastal areas, but this was not the case with the bivalves. The results of this study suggest that some gastropod species may be a potential bioindicator or “sentinel” organism for marine PCBs monitoring.
Increase of the Behavioral Response to Kairomones by the Parasitoid Wasp Leptopilina heterotoma Surviving Insecticides by J. M Delpuech; C Bardon; M Boulétreau (pp. 186-191).
Hymenopterous parasitoids are key species involved in the regulation of insect populations. Kairomone perception is an important step leading to host parasitization. The massive use of insecticides induces environmental pollution that can interact with the reproduction of parasitoids. In this work, we have determined the sublethal effects of two insecticides, an organophosphorus (chlorpyrifos) and a pyrethroid (deltamethrin), on the arrestment, by host kairomones, of female parasitoids surviving an LD 20 for 24 h. The behavior of the parasitoids has been recorded with a video-computerized system. The analysis of the behaviors in control conditions versus exposed to an LD 20 have shown that both insecticides significantly increased the arrestment of parasitoids by kairomones. This increase was not followed up by a modification of the kinetics of the behavior. In both control and exposed conditions, parasitoids regularly increased their residence time on the kairomone patch indicating that no saturation to kairomones had occurred. In a field situation where hosts could be scarce, this increase in arrestment could be advantageous for parasitoids by increasing their host finding.
Accumulation of Toxicants in Tadpoles of the Common Frog (Rana temporaria) in High Mountains by R. Hofer; R. Lackner; G. Lorbeer (pp. 192-199).
We analyzed the accumulation of inorganic and organic toxicants in tadpoles from nine populations of the common frog (Rana temporaria) at different altitudes of the Hohe Tauern National Park in Austria). Lead and cadmium concentrations in tadpoles increased with the acidity and metal-to-HCO3– ratio in the water exceeding those found in tadpoles from agricultural areas. Organochlorines (DDTs, polychlorinated biphenyls, lindane) and polyaromatic hydrocarbons were present in all of the populations, but only DDTs accumulated significantly compared with the concentrations in their diet.
Alterations of Metabolic Enzymes in Australian Bass, Macquaria novemaculeata, After Exposure to Petroleum Hydrocarbons by A Cohen; M M Gagnon; D Nugegoda (pp. 200-205).
Australian bass Macquaria novemaculeata were exposed to the water-accommodated fraction of Bass Strait crude oil, dispersed crude oil, or burnt crude oil to assess sublethal effects of oil spill remediation techniques on fish. Fish were exposed to these treatments for 16 days either through the water column or by way of a pre-exposed diet of amphipod Allorchestes compressa. Fish gills, liver, and white muscle were sampled and cytochrome C oxidase (CCO) and lactate dehydrogenase (LDH) activities quantified. In all treatments containing fish exposed by way of the water column, aerobic activity increased in the gills, whereas a decrease of this enzymic activity was observed in the liver and white muscle. Exposures by way of the food pathway indicated similar trends. Anaerobic (LDH) activity increased in the gills, liver, and white muscle after waterborne exposures. Stimulation in anaerobic activity also occurred in the liver and white muscle of fish after exposure to contaminated food. CCO activity in the gills was the most sensitive biomarker when monitoring waterborne exposures to petroleum hydrocarbons. In the gills, the dispersed oil treatment resulted in the most pronounced biological response, suggesting that in the short term the use of dispersants on an oil slick might cause the most perturbations to fish metabolism.
Comparative Toxicokinetics of Explosive Compounds in Sheepshead Minnows by G. R. Lotufo; M. J. Lydy (pp. 206-214).
Juvenile sheepshead minnows Cyprinodon variegatus were exposed to the explosive compounds 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro−1,3,5,7-tetranitro−1,3,5,7-tetrazocine (HMX) and to the TNT transformation products 2-aminodinitrotoluene (2-ADNT) and 2,4-diaminonitrotoluene (2,4-DANT) in five separate water-only experiments. A one-compartment model was used to characterize uptake (ku) and elimination (ke) rate constants and to estimate bioconcentration factors (BCFs). The compounds investigated in this study are weakly hydrophobic. Kinetically derived BCFs (9.6, 13.1, 0.5, 1.7, and 0.5 ml g–1 for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively) confirmed the expected low bioaccumulative potential of those compounds and the positive relationship between log BCF and log Kow (1.6, 2.0, 0.8, 0.9, and 0.2 for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively). The uptake clearance (ku) was relatively slow for all compounds (7.3, 12.6, 1.3, 0.15, and 0.06 ml g–1h–1 for TNT, 2-ADNT, 2,4-DANT, RDX, and HMX, respectively), and overall, it decreased with decreasing compound hydrophobicity. Elimination was extremely fast for the nitroaromatic compounds (0.77, 0.96, and 2.74 h−1 for TNT, 2-ADNT, and 2,4-DANT, respectively), thus resulting in very short biological half-lives (<1 hour), but it was much slower for the cyclonitramines (0.09 h–1 for RDX and 0.12 h−1 for HMX). Although ADNTs were present in fish exposed to TNT, the parent compound was the dominant compound in tissues during the uptake and elimination exposures. The rates of metabolite formation (0.06 h–1) and elimination (0.16 h–1) were much slower than the rate of elimination of the parent compound (0.80 h–1). Because of the fast elimination rate of TNT and its transformation products and the exceedingly low bioaccumulative potential of RDX and HMX, exposure conditions likely associated with the presence of explosives in aquatic systems are unlikely to pose unacceptable risks to fish.
Effects of Dietary Administration of CL-20 on Japanese QuailCoturnix coturnix japonica by G Bardai; G I Sunahara; P A Spear; M Martel; P Gong; J Hawari (pp. 215-222).
Hexanitrohexaazaisowurtzitane, or CL-20, is an emerging highly energetic compound currently under consideration for military applications. With the anticipated wide use of CL-20, there is the potential for soil and groundwater contamination resulting in adverse toxicologic effects on environmental receptors. Presently, there is a lack of data describing the toxic effects of CL-20 on avian species. The present study describes the effect of CL-20 on Japanese quail (Coturnix coturnix japonica) modified from standard toxicity test guidelines. First, a 14-day subacute assay was adopted using repeated gavage doses (0, 307, 964, 2439, 3475, or 5304 mg CL-20/kg body weight (BW)/d for 5 days followed by no CL-20 exposure (vehicle only) for 10 days. Second, a subchronic feeding assay (0, 11, 114, or 1085 mg CL-20/kg feed) was done for 42 days. During both studies, no overt toxicity was observed in the CL-20–treated birds. During the first 5 days of the subacute study, CL-20–exposed birds showed a dose-dependent decrease in BW gain, whereas increased liver weight, plasma sodium, and creatinine levels were observed in birds receiving the highest dose tested. For the subchronic study, embryo weights were significantly decreased in a dose-dependent manner. Embryos from CL-20–exposed birds were observed to have multiple cranial and facial deformities, beak curvatures, possible mid-brain enlargement, and classic one-sided development with micro-opthalamia (nonstatistical comparisons with control embryos). A trend toward decreased number of eggs laid per female bird was also observed. We conclude that CL-20 (or its degradation products) elicits few effects in adults but may affect avian development, although these preliminary findings should be confirmed.
Bioaccumulation of PCBs in Burbot (Lota lota L.) After Delivery in Natural Food by J.-P J Pääkkönen; A.-L Rantalainen; A Karels; A Nikkilä; J Karjalainen (pp. 223-231).
Burbot (Lota lota) caught from Lake Päijänne, Central Finland, were exposed under laboratory conditions to four polychlorinated biphenyl (PCB) congeners delivered through diet, and accumulation of congeners to muscle, intestine, gonads, and liver were determined. The selected PCB congeners (PCB18, PCB44, PCB137, and PCB169) were added to intact dead vendace (Coregonus albula) and burbot were fed 5 or 10 contaminated meals (2- and 4-week experiment, respectively). Concentrations of fed congeners were different in the examined tissues. The highest concentrations of all the congeners were found in the livers of burbot. The mean retention efficiencies were 65.0% and 81.7% after 5 and 10 oral doses, respectively. The retention efficiency of the coplanar 169 was lower than those of the other fed congeners. The background organochlorine concentrations of the burbot of this study were compared with the PCB concentrations of burbot caught in the 1970s from Lake Päijänne. These concentrations were compared in order to clarify the PCB load and persistence in a boreal aquatic food web. The total PCB concentration in burbot has not declined during the last decades. The most abundant PCB congeners in the field were PCB138 and PCB153. Residual concentrations of pesticides were also found, especially the DDE, which is a metabolite of DDT.
Use of Skin and Blood as Nonlethal Indicators of Heavy Metal Contamination in Northern Water Snakes (Nerodia sipedon) by J Burger; K.R Campbell; T.S Campbell; T Shukla; C Jeitner; M Gochfeld (pp. 232-238).
Relatively little is known about contaminants in reptiles, particularly snakes. The concentrations of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium were examined in blood and skin of 46 northern water snakes (Nerodia sipedon) in Tennessee and correlated with concentrations in internal tissues (liver, kidney, muscle) to determine if blood or skin could serve as a nonlethal indicator of internal metal exposure or body burden. Snakes were collected from the East Fork Poplar Creek (EFPC) within the United States Department of Energy’s Y-12 National Security Complex (part of the Oak Ridge National Laboratory) and from a reference stretch of the Little River in East Tennessee. For blood, the only consistent positive correlations with internal organs were for mercury, and correlations were low except for muscle. Skin showed significant positive correlations with all three organs for mercury, chromium, selenium, and lead. For manganese and cadmium, skin level was positively correlated with liver level. Blood generally reflects recent exposure, not necessarily body burden, but in water snakes it correlates with body burden for mercury. Skin proved useful for more metals, although patterns were not necessarily consistent across sex and locality subgroups. The most consistent pattern was for mercury, the metal of greatest concern in many aquatic ecosystems, including EFPC.
Heavy Metal Concentrations in Northern Water Snakes (Nerodia sipedon) from East Fork Poplar Creek and the Little River, East Tennessee, USA by K R Campbell; T S Campbell; J Burger (pp. 239-248).
We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in the blood, kidney, liver, muscle, and skin of northern water snakes (Nerodia sipedon) collected from the upper reach of East Fork Poplar Creek (EFPC) within the United States Department of Energy’s (USDOE’s) Y-12 National Security Complex with concentrations in tissues of northern water snakes from a reference reach of the Little River downstream from the Great Smoky Mountains National Park in East Tennessee. Our objectives were to determine whether concentrations of these metals were higher in tissues of water snakes collected from EFPC compared with the reference site and if northern water snakes were suitable bioindicators of metal contamination. Except for chromium, metal levels were significantly higher in tissues (kidney, liver, muscle, and skin) of EFPC northern water snakes compared with those in tissues of snakes from the reference site. Although female northern water snakes were significantly larger than male snakes, their tissues did not contain significantly higher metal concentrations compared with those from male snakes, possibly because of maternal transfer of metals to eggs. This study was the first to examine the accumulation of contaminants resulting from the operations of the USDOE’s Oak Ridge Reservation in snakes.
Heavy-Metal Concentrations in Female Laying Great Tits (Parus major)and Their Clutches by T. Dauwe; E. Janssens; L. Bervoets; R. Blust; M. Eens (pp. 249-256).
Egg laying may be an additional excretory pathway for heavy metals available to laying female birds. In this study, we examined the relationships between tissue concentrations (both internal organs and feathers) of 10 breeding female great tits (Parus major) and the concentrations in their eggs. We also investigated differences in metal concentrations (Ag, Al, As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Zn) among eggs as a result of the laying order of the eggs. Heavy-metal concentrations in internal tissues were highest in bone (Cr, Ni, Pb, Zn), kidney (Cd), liver (Cu), blood (Al, As, Co, Hg), and intestine (Ag, Mn). In the egg contents, relatively high concentrations of the essential elements Cr, Co, Cu, Mn, Ni, and Zn were found. In eggshells, concentrations of Ag, Al, As, Co, Cr, and Ni were high compared with internal tissue concentrations. Metal concentrations in the egg contents and eggshells were poorly correlated with metal concentrations in internal tissues and feathers; significant positive correlations were found only for cadmium and lead. We found few significant differences in metal concentrations among eggs, and none were according to the laying order of the eggs. The egg volume tended to decrease significantly as egg laying progressed. Our results seem to suggest that no special sampling strategies (e.g., sampling the first egg or pooling eggs from one clutch) are required for most metals.
Retrospective Ecotoxicological Data and Current Information Needs for Terrestrial Vertebrates Residing in Coastal Habitat of the United States by B. A. Rattner; K. M. Eisenreich; N. H. Golden; M. A. McKernan; R. L. Hothem; T. W. Custer (pp. 257-265).
The Contaminant Exposure and Effects—Terrestrial Vertebrates (CEE-TV) database was developed to conduct simple searches for ecotoxicological information, examine exposure trends, and identify significant data gaps. The CEE-TV database contains 16,696 data records on free-ranging amphibians, reptiles, birds, and mammals residing in estuarine and coastal habitats of the Atlantic, Gulf, and Pacific coasts, Alaska, Hawaii, and the Great Lakes. Information in the database was derived from over 1800 source documents, representing 483 unique species (about 252,000 individuals), with sample collection dates spanning from 1884 to 2003. The majority of the records contain exposure data (generally contaminant concentrations) on a limited number (n = 209) of chlorinated and brominated compounds, cholinesterase-inhibiting pesticides, economic poisons, metals, and petroleum hydrocarbons, whereas only 9.3% of the records contain biomarker or bioindicator effects data. Temporal examination of exposure data provides evidence of declining concentrations of certain organochlorine pesticides in some avian species (e.g., ospreys, Pandion haliaetus), and an apparent increase in the detection and possibly the incidence of avian die-offs related to cholinesterase-inhibiting pesticides. To identify spatial data gaps, 11,360 database records with specific sampling locations were combined with the boundaries of coastal watersheds, and National Wildlife Refuge and National Park units. Terrestrial vertebrate ecotoxicological data were lacking in 41.9% of 464 coastal watersheds in the continental United States. Recent (1990–2003) terrestrial vertebrate contaminant exposure or effects data were available for only about half of the National Wildlife Refuge and National Park units in the geographic area encompassed by the database. When these data gaps were overlaid on watersheds exhibiting serious water quality problems and/or high vulnerability to pollution, 72 coastal watersheds, and 76 National Wildlife Refuge and 59 National Park units in the continental United States were found to lack recent terrestrial vertebrate ecotoxicology data. Delineation of data gaps in watersheds of concern can help prioritize monitoring in areas with impaired water quality and emphasize the need for comprehensive monitoring to gain a more complete understanding of coastal ecosystem health.
Statistical Model of Pesticide Penetration Through Woven Work Clothing Fabrics by Seungsin Lee; S. Kay Obendorf (pp. 266-273).
Statistical models estimating the level of protection and thermal comfort performance of woven fabrics were developed using simple fabric and liquid parameters. Eighteen woven fabrics were evaluated against three pesticide mixtures of atrazine and pendimethalin at different concentrations. Using three mixtures that represent a range of both surface tension and viscosity, percentages of pesticide penetration are measured, along with fabric thickness, fabric cover factor, yarn twist factor, yarn packing factor, solid volume fraction, wicking height, and air permeability. Statistical analyses are performed to examine the relationship between liquid/fabric parameters and pesticide penetration. Statistical analyses show that fabric cover factor, yarn twist factor, viscosity of pesticide mixture, critical surface tension of solid, and wicking height are significant parameters affecting pesticide penetration. For this purpose, cover factor and twist factor are better parameters in describing the geometry of woven fabrics than solid volume fraction. Modeling of comfort performance of woven fabric based on simple textile parameters shows that the combination of fabric thickness, cover factor, yarn twist factor and yarn packing factor can be used to estimate air permeability of woven fabric. These findings could be used for developing selection charts or tools as guidelines for the selection of personal protective equipment for use in hot, humid environments.
Polychlorinated Biphenyls and Organochlorine Pesticides in Human Adipose Tissue and Breast Milk Collected in Hong Kong by B H T Poon; C K M Leung; C K C Wong; M H Wong (pp. 274-282).
Contamination from persistent organic pollutants is a pervasive global problem that urgently demands global concern and action. In the present study, concentrations of organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) were determined in 37 samples of female adipose tissue collected in Hong Kong hospitals. Among the pollutants analyzed, DDTs (2.79 ng/g fat), HCHs (0.72 ng/g fat), and PCBs (0.19 ng/g fat) were prominent compounds in most of the adipose tissue. p,p′-DDE and hexachlorinated biphenyls were found in all samples, whereas heptachlor epoxide and dieldrin were found only in some samples. An estimation of toxic equivalency concentration (TEQ) due to dioxin-like coplanar PCBs was also performed. The estimated TEQPCBs was 2.01 pg/g fat. This study also compared our previous results obtained from the milk samples of the same donors. Significant correlations are obtained for DDTs and HCHs between milk and adipose tissue. Detailed review of available information concerning OC pesticides and PCBs in different ecological compartments indicated that bioconcentration and biomagnification of these contaminants are common phenomena of the Pearl River Delta region, which has undergone rapid socioeconomic change in the past 20 years. It is suggested to establish a regional organization in order to coordinate the monitoring of persistent organic pollutants in the region.
