Risk mitigation of genetically modified bacteria and plants designed for bioremediation

  • John DavisonEmail author
Environmental Biotechnology


While the possible advantages of bioremediation and phytoremediation, by both recombinant microbes and plants, have been extensively reviewed, the biosafety concerns have been less extensively treated. This article reviews the possible risks associated with the use of recombinant bacteria and plants for bioremediation, with particular emphasis on ways in which molecular genetics could contribute to risk mitigation. For example, genetic techniques exist that permit the site-specific excision of unnecessary DNA, so that only the transgenes of interest remain. Other mechanisms exist whereby the recombinant plants or bacteria contain conditional suicide genes that may be activated under certain conditions. These methods act to prevent the spread and survival of the transgenic bacteria or plants in the environment, and to prevent horizontal gene flow to wild or cultivated relatives. Ways in which these genetic technologies may be applied to risk mitigation in bioremediation and phytoremediation are discussed.


Phytoremediation Genetically modified organisms Biosafety Horizantal gene transfer Risk-assessment 



This work was partially supported by an integrated research project (Co-Extra, Contract No 007158) from the European Community Framework 6 Programme.


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Copyright information

© Society for Industrial Microbiology 2005

Authors and Affiliations

  1. 1.Laboratory of Cellular BiologyInstitut National de la Recherche AgronomiqueVersaillesFrance

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