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1.
We have studied the acute toxicity of fluoride ion to Gasterosteus aculeatus, Pimephales promelas, and juvenile Salmo gairdneri. LC50 values varied with species and (due to precipitation) initial water hardness. Exposure to elevated fluoride levels in water resulted in increased blood fluoride levels in Salmo gairdneri.  相似文献   

2.
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   

3.
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   

4.
A mixture of ten metals (As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se and Zn) at the Great Lakes Water Quality Objective levels was found to reduce the primary productivity of four cultured freshwater algae (Scenedesmus, Chlorella, Anabaena and Navicula) as well as natural phytoplankton from Lake Ontario water. The metal mixture also caused a reduction in the reproduction and transport of an amino acid analogue (α-aminoisobutyric acid) by Ankistrodesmus. The depuration and exchange of the amino acid analogue were not affected by the metal mixture. The nitrogenase activity of Anabaena was, however, reduced in the presence of the metal mixture.  相似文献   

5.
Accumulation of 14C labelled bis(tributyltin) oxide (TBTO) by the mud crab, Rhithropanopeusharrisii, was determined through short-term exposure to labelled water and food. The potential for trophic accumulation during chronic low level exposure is emphasized.  相似文献   

6.
This paper reports the bioaccumulation of three PCBs (2,4′-dichlorobiphenyl, 2,4,6,2′-tetrachlorobiphenyl and 2,4,6,2′,4′-pentachlorobiphenyl) by the green alga Chlorellafusca under various conditions. A probable pattern of the bioconcentration mechanism is suggested. No metabolites were extracted from algae or water 6 days after incubation with PCBs.  相似文献   

7.
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   

8.
Killifish (Fundulussimilis) were exposed in the laboratory to pentachlorophenol (PCP) at concentrations of 57 to 610 μg PCP/L. Bioaccumulation reached a plateau value of about 53 by 168 hrs and remained at this level for at least 72 hrs. One-half the plateau value was reached in about 25 hrs. Following exposure, fish placed in PCP-free aquaria lost PCP rather slowly (t12 ~ 4.7 days). The depuration data were suggestive of a pool of PCP which was lost more rapidly (t12 ~ 4.2 hrs). The results of this study are compared to similar studies in other species. The bioaccumulation factors measured in this study agree relatively well with those in other marine species, but are lower than reported for fresh water species. Possible reasons for this difference are discussed.  相似文献   

9.
The photolysis of methyl 2-benzimidazolecarbamate (Carbendazim, 1) in methanol and in the presence of singlet oxygen, was studied. Dimethyl oxalate 4, 2-aminobenzimidazole 7, benzimidazole 9, N,N′-dicarbomethoxyguanidine 13, monocarbomethoxyguanidine 14, monocarbomethoxyurea 15, and 2-guanidinobenzimidazole 17, were isolated and identified in this reaction.A mechanism that accounts for the formation of the photoreaction products, is presented.  相似文献   

10.
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   

11.
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   

12.
Aniline partially degraded in sterile soil to azobenzene, azoxybenzene, phenazine, form=anilide, and acetanilide. Nitrobenzene, p-benzoquinone, and unidentified species were possible products; substantial bound residues may also have formed. Soil-catalyzed conversion of aniline or [d5]aniline seems evidenced by 6-24X more product recovery in sterile soil than in sterile water alone, a process inhibited by Na2S2O4. Freundlich adsorption constants showed: azobenzene > azoxybenzene > phenazine > aniline.  相似文献   

13.
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   

14.
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   

15.
Photolysis (254 nm, 72h) of 1-nitro-2-phenylnaphthalene 1 in methanol gave 2-phenyl-1,4-naphthoquinone-4-monoxime 2, 2,2′-diphenyl-4,4′-binaphth-1,1′-diol 3 and 2,2′-diphenyl-4,4′-binaphth-1,1′-dione 4. Straightforward reactions available to the environment account for the formation of the products: (a) isomerisation of the nitro compound into a nitrite ester followed by either (a) migration of the nitroso group and isomerisation into the oxime 2 or (b) oxidative coupling and solvolysis into the binaphthol 3 and followed by oxidation into the binaphthone 4.  相似文献   

16.
C.M. Tu 《Chemosphere》1981,10(1):127-134
A study of the effect of 5 fungicide seed treatments on alfalfa (Medicagosativa L. var. Vernal) growth and nodulation by Rhizobiummeliloti 102F66 was conducted in a growth chamber. Captan, maneb and thiram exhibited greater toxicity to R. meliloti and alfalfa plants than that of benomyl and zineb. Recovery of the inhibitory effect was rapid.  相似文献   

17.
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   

18.
Daniel Barug 《Chemosphere》1981,10(10):1145-1154
The degradation of the biocide bis (tributyltin) oxide by pur cultures of microorganisms has been studied. Attempts to isolate microorganisms able to utilize bis (tributyltin) oxide as sole carbon source, were unsuccessful. Of many bacterial species investigated Pseudomonas aeruginosa and Alcaligenes faecalis degraded sublethal amounts of bis (tributyltin) oxide during aerobic growth in the presence of suitable carbon sources. P. aeruginosa converted bis (tributyltin) oxide into monobutyltin and small amounts of dibutyltin derivatives. Similar results were obtained with growing mycelium of Coniophora puteana, Trametes versicolor and Chaetomium globosum. Microbial conversion of monobutyltin trichloride was not observed. Dibutyltin dichloride was converted into monobutyltin derivatives under certain sterile conditions.  相似文献   

19.
Tissue cadmium levels and the amount of metal associated with the various protein fractions thereof have been determined in specimens of Mytilus edulis exposed to cadmium in the water and by direct injection. In addition to metallothionein, heavy-molecular weight proteins are involved in cadmium retention.  相似文献   

20.
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   

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