ISSN:0730-7268    

DOI:10.1002/etc.5620120501

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractMeasurements were made of the biodegradation of 4‐chloro‐4‐deoxy‐α, D‐galactopyranosyl‐1,6‐dichloro‐1,6‐dideoxy‐β, D‐fructofuranoside (sucralose) in samples of several natural environments. This chlorinated carbohydrate, which represents a new class of artificial sweeteners, was extensively transformed to CO2in four mineral soils with pH values of 4.9 to 7.2. Mineralization occurred at concentrations of 0.01 to 1,000 mg of sucralose per kilogram of soil, and the initial rates were a direct function of substrate concentration. At the lower concentrations, mineralization was initiated with no detectable acclimation period. Mineralization was not evident in soil under anaerobiosis. Mineralization occurred in lake sediments, sewage, and estuarine water but at lower rates and lesser extents than in soils. Little mineralization was evident in samples from oligotrophic, mesotrophic, and eutrophic lakes, the extent of mineralization being often less than the contamination level of the sucralose preparation. Sucralose degradation resulted from microbial activity because mineralization did not occur in sterilized environmental samples, and the addition of cycloheximide or streptomycin to soil significantly reduced mineralization. No bacterium could be isolated that was capable of utilizing sucralose as the sole carbon source. The data suggest that the biodegradation of sucralose i

ISSN:0730-7268    

DOI:10.1002/etc.5620120502

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractSignificant concentrations of C12to C26n‐alkanes, fluoranthene and pyrene were found in dichloromethane extracts of filtered Niagara River water at pH 12 after the water had been thoroughly extracted at pH 1. Over 40 sampling days, the total concentration ofnalkanes, fluoranthene, and pyrene in the basic extracts was roughly 60% of the total in the acidic extracts plus suspended solids combined. Spike recovery experiments with 31n‐alkanes and polynuclear aromatic hydrocarbons demonstrated that the phenomenon (a) did not occur in distilled water, (b) occurred in Niagara River water, regardless of whether the initial extraction of filtered water was performed at acidic or neutral pH, and (c) was not simply the result of incomplete extraction at acidic or neutral pH. These findings support earlier studies that suggested that concentrations of lipophilic organic chemicals in Niagara River water may be underestimated when determined by the usual technique of extraction at neutral

ISSN:0730-7268    

DOI:10.1002/etc.5620120503

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractFog water and interstitial air samples were collected simultaneously and analyzed for methoxylated phenols, which have been previously reported as incomplete combustion products from wood lignin. The purposes of this study were to ascertain if these methoxylated phenols could be detected in fog sampled in residential areas and to determine the distribution of the compounds between fog droplets and interstitial air. The fog water was collected with a Teflon® filament fog collector and filtered through a 0.2‐μm filter before extraction and GC analysis. Vapor samples were collected using a dichotomous sampler to separate fog droplets from interstitial air; the organic vapors were collected on polyurethane foam. Guaiacol, 4‐methylguaiacol, and syringol were the most commonly found among the 16 methoxylated phenols confirmed in fog samples. The distributions between air and water approximately followed Henry's law, suggesting that previously reported enrichments into fog water are related to analyte hydrophobicity, described by either the octanol/water partition coefficient or the water solub

ISSN:0730-7268    

DOI:10.1002/etc.5620120504

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractBioassay‐directed fractionation of organic compounds was performed on an organic solvent extract of a contaminated estuarine sediment from Black Rock Harbor, Connecticut, using the new mutagenic bioassay, Mutatox™. Chemical fractionation methods of the sediment extract included silica‐gel‐column chromatography (SGCC), followed by C18reverse phase HPLC. Compound identification was performed using GC‐MS. Mutatox analyses indicated that four of the eight HPLC fractions contained mutagenic or epigenetic compounds. GC‐MS analyses detected known mutagenic polycyclic aromatic hydrocarbons (PAHs) in two of the four mutagenic fractions. GC‐MS analyses of the other two mutagenic fractions (one operational blank and one sediment fraction) showed no known mutagenic compounds. SGCC and HPLC, combined with the Mutatox bioassay, were useful in reducing both the number and the complexity of fractions analyzed by GC‐MS. The Mutatox bioassay is a promising tool for bioassay‐direc

ISSN:0730-7268    

DOI:10.1002/etc.5620120505

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractThe objectives of this study were to test the hypothesis that bioaccumulation of hydrophobic organic compounds (HOCs) by phytoplankton is correlated to the compound's octanol/water partition coefficient (Kow) in a predictive relationship in laboratory experiments, and to confirm these findings with field observations. In laboratory experiments we measured the uptake of 40 representative polychlorinated biphenyl (PCB) congeners over time under conditions that inhibited and allowed phytoplankton growth. Results indicated that the bioaccumulation process is consistent with partitioning from water into cell lipids but is slower than previously thought. The uptake of PCBs was slow relative to growth of phytoplankton, preventing the chemical from reaching thermodynamic equilibrium in algal cells under conditions promoting growth (nonwinter). Thus under non‐winter field conditions, many PCB congeners never reach equilibrium concentrations. Food‐chain models that assume equilibrium between HOCs and the primary trophic level could be inaccurate and may need to use a kinetic framew

ISSN:0730-7268    

DOI:10.1002/etc.5620120506

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractPetroleum oil has caused hemolytic anemia in birds and mammals. In birds, an oxidant damage on circulating red cells has been identified as the primary toxic effect of ingested petroleum oils. An in vitro red blood cell assay was developed to discriminate among the oxidant activities of different petroleum oils. The assay used rabbit red blood cells with a rat liver enzyme system and formation of methemoglobin was measured as an indicator of oxidant damage to the red cells. The assay was applied to five different petroleum oils and to naphthalene, a petroleum hydrocarbon known to cause hemolytic anemia. Different petroleum oils differed in their capacity to induce methemoglobin formation. Methemoglobin levels varied from 2.9% with Arabian light crude oil to 6.2% with South Louisiana crude oil. Naphthalene induced formation of up to 37% methemoglobin. Naphthalene and the five petroleum oils generated methemoglobin only in the presence of liver enzymes.

ISSN:0730-7268    

DOI:10.1002/etc.5620120507

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractField and laboratory tests were conducted to determine the 10‐d toxicity of atrazine and carbofuran to larvae of the midgeChironomus tentans.The pesticides were first spiked onto a clean control sediment, and the midges were exposed to atrazine, carbofuran, or mixtures of both compounds. Laboratory toxicity tests with carbofuran yielded LC50s of 20.5 μg/kg bound to sediment and 11.8 μg/L dissolved in interstitial water. Slight but statistically significant toxicity was detected at the highest tested concentration of atrazine (9,000 μg/kg, bound). Toxic interaction between the two pesticides was assessed using all possible combinations of four concentrations of both pesticides spiked onto clean sediments. Analysis of variance was used to determine if greater than or less than additive effects occurred when both pesticides were present. No toxic interaction between atrazine and carbofuran was detected. Based on laboratory findings, it was predicted that edge‐of‐field runoff could be toxic to midge larvae if concentrations of carbofuran exceeded 5 μg/kg. To test these predictions, actual edge‐of‐field runoff was collected from a cornfield receiving atrazine and carbofuran at recommended rates and the suspended sediments used in a toxicity test. Edge‐of‐field runoff containing carbofuran at 186 μg/kg was acutely tox

ISSN:0730-7268    

DOI:10.1002/etc.5620120508

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractLevels of persistent pollutants, including PCBs, ΣDDT, and γ‐hexachlorocyclohexane, were examined in a pike population inhabiting a eutrophic lake in southern Scandinavia. For females, levels of persistent pollutants decreased linearly with age, weight, or length. This decline was ascribed to the seasonal elimination of the lipophilic pollutants in roe, which contained up to 10 times higher fat levels compared to muscle and over 10 times the amounts of pollutants. Male pike contained higher levels of pollutants than females, probably due to the lower elimination via gonadal products, as germinal tissue constitutes only 2% of the male total body weight and has a lower fat content than ovaries. Female germinal tissue can account for as much as 15% of the body weight. No major fat deposits other than those in germinal tissue were found in pike, which also had a low muscle fat content, suggesting that the importance of roe elimination in removing pollutants may be greater in pike than in salmonids. Uptake of persistent pollutants can vary greatly within a species, owing to differences in sex, age, and so forth, as well as between species, owing to differences in fat deposition strateg

ISSN:0730-7268    

DOI:10.1002/etc.5620120509

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY

摘要:

AbstractAcute toxicity in earthworms (Lumbricus terrestris) was assayed immediately after 5‐d filter paper exposure to the polychlorinated biphenyl (PCB) Aroclor 1254, using coelomocyte viability, total extruded cell counts (ECC), differential cell counts (DCC), and formation of erythrocyte (ER) and secretory rosettes (SR) with, and phagocytosis of, antigenic rabbit red blood cells (RRBC). Chronic toxicity was assayed using rates by which earthworms replaced viable immunoactive coelomocytes, removed noninvasively immediately after exposure, over an 18‐week depuration period. All cytological parameters, except ECC, were acutely affected immediately after exposure, when tissue concentrations were (X± se) 91.2 ± 8.19 μg PCB per gram dry mass. Replacement of viable immunoactive coelomocytes occurred within six weeks in unexposed control earthworms. Exposed earthworms showed significant alteration in viability, ECC, DCC, ER, and SR formation, and phagocytosis at 6 and 12 weeks when PCB tissue concentrations were 41 ± 0.31 and 30.2 ± 0.88 μg/g dry mass, respectively. Replacement of extruded coelomocytes with normal DCC of viable immunocompetent cells was not observed until week 18, when PCB had decreased to 15.7 ± 0.83 μg/g dry mass. Low inherent natural variability in coelomocyte viability, ECC, DCC, rosette formation, and phagocytosis, and their sensitivity to sublethal PCB body burdens, indicated that earthworm coelomocytes have potential as nonmammalian biomarkers for assaying acute and chronic sublethal toxicity of

ISSN:0730-7268    

DOI:10.1002/etc.5620120510

出版商:Wiley Periodicals, Inc.    

年代:1993

数据来源: WILEY