Root growth inhibition and induction of DNA damage in soybean (Glycine max) by chlorobenzenes in contaminated soil.
The cytotoxic and genotoxic effects of 1,2,4-trichlorobenzene (TCB), chlorobenzene (CB), and hexachlorobenzene (HCB) on root growth and DNA strand breakage damage of soybean nuclei in the test soil were studied using the comet assay. Results indicated that the root growth was significantly inhibited, and DNA strand breaks and the comet tail in the root tip nuclei were both induced after 48 h exposure with TCB concentrations of 50, 100, 200, 300 microg g(-1) in the soil. DNA strand breakage was more sensitive to the TCB than the root growth. There was a significant dose-response relationship between the TCB exposure and DNA strand breakage in the soybean nuclei. Thus it is possible for DNA strand breakage to be used as a biomarker of soybean exposed to TCB contamination. Significant cytotoxic threshold concentration of the TCB exposure on the root growth inhibition was determined as 61 microg g(-1) in the soil. The toxicity of 100-1,000 microg g(-1) CB and HCB to the soybean seedlings in the soil were not observed after 48 h or longer exposure.
Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
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Liu
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Yang
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Li
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Zhou
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Sun
D002455:Cell Division / Q000187:drug effects; D002722:Chlorobenzenes / Q000633:toxicity*; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure; D006581:Hexachlorobenzene; D009153:Mutagens / Q000633:toxicity; D018517:Plant Roots / Q000187:drug effects* / Q000254:growth & development; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development; D012989:Soil Pollutants / Q000378:metabolism / Q000633:toxicity*; D013025:Glycine max / Q000187:drug effects* / Q000254:growth & development; D013997:Time Factors
D002722:Chlorobenzenes; D009153:Mutagens; D012989:Soil Pollutants; C036720:trichlorobenzene; D006581:Hexachlorobenzene