摘要:

AbstractTen short‐term toxicity tests were run for ten different industrial wastewaters. The tests included standardized toxicity tests with bacteria, microalgae, higher plants, invertebrates, and fish. An algal test battery of 13 microalgae was also run in microplates. The results were compared with regard to the tests' relative sensitivity and the similarity in sensitivity patterns between different tests. The test with highest sensitivity was the algal test battery. This was due to the fact that the algal species in the battery had complementary sensitivity patterns. The sensitivity patterns of the zoological tests had a high degree of similarity and they were less sensitive than the microbial tests. The relative sensitivity of a test is, however, dependent on the end point for the tests, and it is pointed out that this must be matched with how the test is interpreted. ©by John Wiley&Sons, I

ISSN:1053-4725    

DOI:10.1002/tox.2530100202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe comprehensive water quality studies on the River Ganga were undertaken at Fatehgarh and Kannauj (U.P.) during 1987–1990. The data revealed significant seasonal variations in the physicochemical and bacteriological properties of the river water. The remarkably high level of coliforms, fecal coliforms, and fecal streptococci reflects the poor quality of the water. Some of theEscherichia coliisolates from the test stretch also exhibited multiple drug resistance. These pollutants render the water unfit for drinking and bathing and may pose serious problems related to public health. ©by John Wiley&Sons, I

ISSN:1053-4725    

DOI:10.1002/tox.2530100203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractToxicity of binary mixtures of organic chemicals was evaluated using the Microtox test, in order to derive a more realistic approach for predicting mixture toxicity. Both additive and less than additive effects were found from binary mixtures of nonreactive toxicants. Concentration addition can be expected between two nonreactive chemicals, provided that the requirement of parallel dose—response curves is fulfilled. The study also identified the conditions for a complex—type joint action to take place. Finally, experimental isobolograms were analyzed based on a bivariate toxicity model to provide a rational estimation of model parameters. The isobolograms and the additive indices generated by this study can be used to predict the combined toxic effects from various organic mixtures. ©by John Wiley&Sons,

ISSN:1053-4725    

DOI:10.1002/tox.2530100204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThis report describes the application of ten bioassays (battery of tests approach) to waters and sediments collected from the tar sands area of northern Alberta, Canada. In this study there were three main goals: (1) to establish the presence and sources of toxicants in these northern waters and sediments, (2) to determine if their presence is related to sediment composition, and (3) to establish which of the various sediment extracting procedures used was most efficient in producing responses in the bioassays used.Results of these investigations indicated that there were two obvious sources of toxicants/genotoxicants, the tar sands extracting area and streams passing through tar sands or oil shales and at least two unknown sources. Based on the techniques used in this study, there does not appear to be a strong sediment structure–toxicant response relationship. Extraction procedure results were variable and are discussed in detail in the report. ©by John Wiley&Sons, I

ISSN:1053-4725    

DOI:10.1002/tox.2530100205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractBiodegradation of trace organic compounds is one of the main mechanisms to purify infiltrating surface water during bankfiltration and underground passage. In anaerobic zones of the underground, rate and extent of degrading processes may be totally different from those in aerobic ones. To investigate this, a model ecosystem was built that reproduces an anaerobic part of the aquifer and the behavior of the three phenoxyacetic acid herbicides 2,4‐dichlorophenoxyacetic acid, (2,4‐D), 2,4,5‐trichlorophenoxyacetic acid (2,4,5‐T), and 2‐Methyl‐4‐chlorophenoxyacetic acid (MCPA) tested. In anaerobic experiments with varying conditions they proved to be almost persistent. Only under aerobic conditions could biodegradation be observed after a lag period. ©by John W

ISSN:1053-4725    

DOI:10.1002/tox.2530100206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe legume root nodules are the site of biological nitrogen fixation in the legume—rhizobium symbiosis. They are a structure unique to this symbiosis and morphologically as well as physiologically distinct from other plant organs. We will present evidence that the formation of nodules (nodulation) may serve for ecotoxicological evaluation of contaminated soil. Substances affecting the macro‐ and/or microsymbionts vitality, such as certain heavy metals or polycyclic aromatic hydrocarbons (PAHs), reduce nodulation before visible damage of the plant occurs. Tests were performed in petri dishes that were planted with alfalfa seedlings and inoculated withRhizobium meliloti. Mineral agar served as substrate. Test substances were added to the mineral agar before pouring it into petri dishes (application of heavy metals), or were sprayed as etheral solutions onto the surface of solidified medium (application of PAHs). For investigation of contaminated soil, the soil material was first mixed with mineral agar and then poured into petri dishes. Appropriate controls were made by extracting an aliquot of soil with methylene chloride to remove hazardous substances. Data from stressed plants were taken after 15 days of cultivation on contaminated substrate. A dose‐responsive decrease in nodulation was found after application of CdCl2, NaAsO2, fluoranthene, and other PAHs. PAH‐contaminated soil (75 mg/kg) caused only a slight reduction in nodulation of alfalfa. But when PAHs were extracted and restored into the extracted soil material, toxicity and uptake of PAHs into roots and shoots dramatically increased. Toxicity and uptake of PAHs were also enhanced by reducing the amount of humic matter added to the test system. ©by John Wiley&S

ISSN:1053-4725    

DOI:10.1002/tox.2530100207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractAn increasing body of evidence suggests that stress may modulate the response of an animal to toxicological challenge. The degree of stress inherent in the procedures comprising a fish LC50study (OECD guidelines for the testing of chemicals, “Fish, Acute Toxicity Test” No. 203, adopted May 12, 1981) was assessed by measuring plasma cortisol levels (rainbow trout) and whole‐body levels of immunoreactive corticosteroids (zebra fish). Aspects of the 96 h LC50protocol which were found to evoke corticosteroidogenic activity in the test fish included transfer from holding tanks to test tanks, tank transfer during semistatic procedures, and disturbance associated with water quality measurement. There was evidence for acclimation of the fish to repetitive stimuli such as tank transfer, but, overall, the data suggest that the 96 h test protocols evoke a state of chronic stress in the test population. The removal of fish from test vessels during longer term studies was also found to evoke a stress response in fish remaining within the vessel, suggesting that these conditions may expose test fish to a regime of intermittent periods of acute stress. The possibility that physiological stress may interfere with the accurate estimation of toxicological end points was examined. In three independent LC50tests the toxicity of the arylmethane dye, malachite green, to rainbow trout was found to be markedly and consistently reduced when the degree of disturbance and handling during the test period was minimized. ©by John Wiley&Son

ISSN:1053-4725    

DOI:10.1002/tox.2530100208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

ISSN:1053-4725    

DOI:10.1002/tox.2530100209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

ISSN:1053-4725    

DOI:10.1002/tox.2530100210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe bacterial bioluminescence assay is widely used to estimate chemical cytotoxicity. This assay is performed most often by using luminescent bacteriaVibrio fisheriNRRL‐B‐11177 (earlier cited asPhotobacterium phosphoreumNRRL‐B‐11177) as a test organism. In this work we have used cloned gram(+) and gram(‐) bacterial strains for the evaluation of chemical toxicity. Two types of luciferase genes were used as reporter genes, one of which was ATP‐dependent eukaryotic luciferase fromPyrophorus plagiophthalamusand the other was FMN‐dependent bacterial luciferase fromVibrio harveyi. These cloned strains were used to evaluate the effects of differences in cell wall structures in the bioluminescence cytotoxicity test using small molecular weight toxic chemicals as model compounds. The strains were found to have remarkably similar behavior and sensitivity toward test toxicants regardless of rather different kinds of membrane structure. However, the eukaryotic luciferase was found in every aspect more useful in toxicity tests than bacterial luciferase mainly because of increased sensitivity and ease of operation. The general behavior of the light emission is described and several aspects affecting the usefulness of the strains are discussed. ©by John W

ISSN:1053-4725    

DOI:10.1002/tox.2530100211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY