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1.
The activities of several commercial PCB mixtures as inducers of microsomal aryl hydroarbon hydroxylase (AHH) and ethoxyresorufin 0-deethylase (EROD) in male Wistar rats and rat hepatoma cells were dependent on the chlorine content (and congener distribution) of the mixtures. The was a correlation between the in vivo and in vitro induction potencies of these mixtures; the most active mixtures, Aroclors 1242, 1248 and 1254 contained 42–54% by weight of Cl whereas formulations with higher or lower (Aroclors 1221 and 1268 respectively) chlorine content exhibited lower activities. This corresponds with studies reported for PCB isomers and congeners in which the most active compounds are tetra-hexachlorobiphenyls.  相似文献   

2.
The analysis presented in this paper shows that water solubility as well as the n-octanol/water partition coefficient are useful indicators of the tendency of organic chemicals to bioaccumulate. It is suggested that these physico-chemical data be used as screening test for organic chemical bioaccumulation in aquatic organisms, such as the mussel Mytilus edulis.  相似文献   

3.
C.M. Tu 《Chemosphere》1982,11(12):1195-1201
Studies on the effects of 21 fungicides and five pyrethroid insecticides on growth of Rhizobiummeliloti, emergence and survival of alfalfa seed and the efficacy of the chemicals in control of Verticillium wilt pathogens were conducted.  相似文献   

4.
5.
The bioaccumulation potential of organic chemicals by the green alga Chlorella fusca was determined. A quantitative relationship was found to exist between the lipophilicity (n-octanol/water partition coefficient) of the chemicals and the bioaccumulation factor.  相似文献   

6.
The effective concentrations of 15 chemicals, inhibiting the cell growth of the alga Scenedesmus subspicatus by 10 % and 50 % during 96 hours, have been investigated in a static test under controlled laboratory conditions.  相似文献   

7.
8.
113 Fishes (pike, vendace and roach) samples were analyzed for chlordane, PCB-and DDT-compounds. The average concentrations in pike (Esox lucius) muscle tissue in Finnish lakes were 0.05, 0.01 and 0.01 mg/kg wet weight for PCB compounds, total DDT and chlordanes respectively. The results show that chlordanes are evenly distributed in the Finnish environment which indicate that the main part of chlordanes in Finnish fish is due to long range transportation.  相似文献   

9.
Discrimination between malignant cells and their normal counterparts by surface properties has been demonstrated by means of two-phase aqueous polymer systems. Primary cultures of normal rat fibroblasts were treated with carcinogens DMBA and DEN. Nonmaliguant mouse fibroblasts of permanent line C3HlOTl2 were treated with carcinogen DB(a,h)A. These treatments change their partition in the direction of their malignant counterparts. Noncarcinogenic phenanthrene affected the cell partition in the reverse direction. The possibility of using two-phase aqueous polymer systems for testing carcinogenic chemicals is discussed.  相似文献   

10.
Y. Ku  G. Alvarez 《Chemosphere》1982,11(1):41-46
N-Phenyl-β-naphthylamine, a widely used rubber antioxidant and antiozonant, was biotransformed into β-naphthylamine, a potent carcinogen, in a laboratory sewage sludge system. β-Naphthylamine appeared to accumulate in the aqueous phase of the system while the undegraded parent compound appeared to be associated with the sludge solids.  相似文献   

11.
A thin film coats impervious urban surfaces that can act as a source or sink of organic pollutants to the greater environment. We review recent developments in the understanding of film and film-associated pollutant behavior and incorporate them into an unsteady-state version of the fugacity based Multimedia Urban Model (MUM), focusing on detailed considerations of surface film dynamics. The model is used to explore the conditions under which these atmospherically-derived films act as a temporary source of chemicals to the air and/or storm water. Assuming film growth of 2.1 nm d−1 (Wu et al., 2008a), PCB congeners 28 and 180 reach air-film equilibrium within hours and days, respectively. The model results suggest that the film acts as a temporary sink of chemicals from air during dry and cool weather, as a source to air in warmer weather, and as a source to storm water and soil during rain events. Using the downtown area of the City of Toronto Canada, as a case study, the model estimates that nearly 1 g d−1 of ∑5PCBs are transferred from air to film to storm water.  相似文献   

12.
This study investigated bioamplification of polychlorinated biphenyls (PCBs) in yellow perch (Perca flavescens) eggs resulting from nutrient utilization by developing embryos during incubation. Newly fertilized eggs containing trace levels of PCBs via maternal deposition were collected from an aquaculture pond in which adult broodstock had been reared over their natural lives. The eggs were incubated using a flow through system that received the same pond water at in-situ temperatures from which they were spawned. Replicate samples of eggs were collected at six time points throughout incubation, ranging from day 0 (newly fertilized eggs) to post-hatch larvae (2-d old). Congener specific PCB fugacities in pooled egg samples showed increases over the incubation period. Just prior to hatching, incubated eggs averaged 2.7-fold higher PCB fugacities compared to fresh eggs. The increase in PCB fugacity with egg incubation time was independent of chemical KOW. After hatching, PCB residues were lost from the larvae, attenuating the maximum chemical fugacity achieved in late-incubated eggs. However, the rate of PCB elimination in the early larvae stages was KOW dependent such that a significant larvae/egg fugacity ratio was still evident for intermediate and highly hydrophobic compounds 2 d post-hatching. This study provides the first evidence of in-ovo PCB bioamplification in eggs of an aquatic species and suggests that incubating fish embryos are exposed to higher chemical fugacities in-ovo than would be predicted by maternal deposition alone.  相似文献   

13.
P. Miramand  M. Unsal 《Chemosphere》1978,7(10):827-832
Acute toxicity of vanadium to some marine benthic and phytoplanktonic speciesThe acute toxicity of vanadium as sodium metavanadate to three benthic (Carcinusmaenas, Mytilusgalloprovincialis, and Nereisdiversicolor) and three phytoplankton species (Dunaliellamarina, Prorocentrummicans and Asterionellajaponica) were studied. In general the phytoplankton were found to be more sensitive than the benthic organisms used in our experiments. Considering the results from LC50 (9 days) experiments, the organisms, can be classified in the following decreasing order of sensitivity: D. marina (0.5 ppm), A. japonica (2 ppm), P. micans (3 ppm), N. diversicolor (10 ppm), C. maenas (35 ppm), M. galloprovincialis (65 ppm).  相似文献   

14.
Water solubilities (SW) determined by the HPLC generator column method are reported for a series of chlorinated dibenzo-p-dioxins (PCDDs) with SW ranging from 0.4 ng/L (ppt) for octa-chlorodibenzo-p-dioxin to 430 ng/L for 1,2,3,7-tetrachlorodibenzo-p-dioxin at 20°C. A correlation is demonstrated between SW and HPLC capacity factors (k′) for these extremely hydrophobic compounds, allowing calculation of SW of PCDDs from k′ and melting point data.  相似文献   

15.
A collecting method to prepare a fractional determination of ambient forms of mercury in air is proposed. Particulate mercury is collected by a glass fiber filter. Sequential trap tubes consist of four long and slender quartz tubes, in which the Chromosorb W treated with HCl gas for Hg(II), the Chromosorb W treated with 0.1 M NaOH for methylmercury, the silver-wire tip for metallic mercury and the gold plate tip for dimethylmercury are packed. The collection efficiency for these trap tubes was in the range of about 85 ~ 100% at the μg or ng concentration level. With this method, the air was collected by suction at the rate of 1.5 l/min. for about five hours, the detection limit being 0.2 ng Hg/m3. The results indicate that the regional distribution of total mercury in air was considerably greater in the volcanic and hot spring regions. Mercury species was found to be mostly Hg(II), followed by metallic mercury, methylmercury, dimethylmercury and particulate mercury in this order.  相似文献   

16.
For the determination of the quantum yields of 1,2,3,4,7-pentachlorodibenzo-p-dioxin (1) and 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin (2), ten Pyrex glass photochemical cells were constructed and their correction factors determined. Quantum yields at 313 nm for 1 and 2 in aqueous acetonitrile (4:6 v/v) were (9.781 ± 2.376) 10?5 and (1.096 ± 0.020) × 10?4, respectively. These quantum yields and the measured absorption spectra were used to estimate the environmental phototransformation first-order rate constants and photochemical half-lives of 1 and 2 in water under conditions of variable sunlight intensity during various seasons from solar intensity data available in the literature. In summer, typical half-lives for the phototransformation of 1 and 2, respectively, near the surface of water bodies at 40° north latitude would be 364 ± 88 and 151 ± 3 h; whilst such values in winter would be 1257 ± 309 and 518 ± 10 h.  相似文献   

17.
J.H. Canton  W. Slooff 《Chemosphere》1982,11(9):891-907
The toxicity of nitrolotriacetic acid (NTA), citrex-S-5, sodium alluminium silicate (NAS), carboxymethyloxysuccinate (CMOS), linear alkylbenzene sulfonate (LAS) and soap was examined using bacteria (Pseudomonasfluorescens), algae (Chlorellavulgaris and Microcystisaeruginosa), crustaceans (Daphniamagna), insects (Aedesaegypti), fishes (Poeciliareticulata and Oryziaslatipes) and amphibians (Xenopuslaevis). The biodegradability of NTA, citrex-S-5, CMOS and LAS was studied in the OECD-test.The acute toxicity of the compounds differed largely with the organisms tested (up to a factor 1,000). Based on the results of the short-term toxicity tests (with all test organisms) and the long-term toxicity tests (with Daphniamagna and in case of LAS also with Poeciliareticulata) the following no-observed-effect concentrations (NOEC) could be derived: LAS 3.2 mg/1; NAS and soap 10 mg/1; CMOS 32 mg/1; NTA 100 mg/1 and citrex-S-5 320 mg/1. However, testing different samples of one test compound may result in marked differences in toxicity (e.g. NAS: a factor 32).All compounds tested showed to be biodegradable as the percentage DOC decreased more than 80% within four weeks. CMOS biodegraded quickly, whereas citrex-S-5 and LAS showed a somewhat slower rate of degradation. In contrast to the other compounds NTA required an adaptation period of 1 week.  相似文献   

18.
C.M. Tu 《Chemosphere》1982,11(10):1027-1033
The relative toxicity of 23 pesticides, including 21 fungicides and two pyrethroid insecticides, on Rhizobiumjaponicum, four soybean pathogens, Fusariumoxysporum, Phytophthoramegasperma, Phytophthoraparasitica and Pythiumultimum, and germination of soybean seeds was compared with a highly toxic broad spectrum germicide, HgCl2 under laboratory conditions.  相似文献   

19.
The kinetics of oxidation of methylhydrazine (MMH) and 1,1-dimethylhydrazine (UDMH) by dissolved oxygen in water has been measured at various acidities as a function of catalyst (cupric ion) concentration. In dilute solutions the oxidation occurs through a cupric ion catalyzed process as well as by an uncatalyzed step. The extent of formation of nitrosodimethylamine (NDMA) depends upon the initial UDMH concentration. In dilute solutions NDMA is not formed, but in more concentrated solutions, NDMA formation increases with increasing UDMH content, reaches a maximum at 60–80% UDMH (by volume) and then decreases. The NDMA yield appears to approximately parallel the viscosity of the medium, and it is speculated that the factors which control viscosity may also be responsible for governing NDMA formation.  相似文献   

20.
Lichens Cladoniaalpestris collected in the northern part of Sweden were analyzed over a 10-year period for chlorinated hydrocarbons. Results show a delay of 2–3 years between the production of PCBs and the deposition of these compounds in the lichen. They confirm the low solubility of PCBs in water and the predominance of atmospheric transport of these chlorinated compounds far away from industrialized areas.  相似文献   

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