Production of Biopesticides from Wastewater Plant Biosolids

EPA acknowledges that lethal activity of bacteria grown in sludge is twice that of bacteria grown with commercial medium
sludge is a better source of food for creating deadly bacteria than the lab grade commercial bacteria food used to grow
bacteria in test procedures.

The bacteria Bacillus thuringiensis (Bt) represents a major class of microbes used for insect biocontrol.

Initial results in laboratory have shown that municipal wastewater sludge can support the growth of Bt and produce
spore and -endotoxins. The entomotoxicity
(lethal activity) produced by different stains of Bt using wastewater sludge as
growth media was higher (50-75 billion IU/gallon) as compared to the entomotoxicity produced using soy based
commercial growth media (30-48 billion


http://cfpub.epa.gov/si/osp_sciencedisplay.cfm?dirEntryID=72155&ActType=project&kwords=Pesticides

Production of Biopesticides from Wastewater Plant Biosolids

Description
:

The control of different kinds of insects and pests that affect agriculture, forestry or that are disease vectors has been
done extensively by the use of chemical insecticides. The use of chemical insecticides has been successful in controlling
these pests but their production is expensive. Because of their mode of action, they can cause many environmental
problems by destroying both harmful and harmless insects. Also, some insects have been shown to be resistant to
chemical insecticides. Chemical pesticides can accumulate in the environment becoming a contamination source for
water and soil thus representing a hazard to users. The use of entomopathogenic microorganisms as biological agents
to control pests may overcome some of the problems of chemical pesticides. The group of microorganisms pathogenic
to insects, which have been proposed, is varied. It includes a broad range of bacteria, viruses, protozoa and fungi; each
of them varying in their mode of infection, site of replication and mechanism of pathogenicity. The bacteria Bacillus
thuringiensis (Bt) represents a major class of microbes used for insect biocontrol. Most Bt strains produce several
different insecticidal proteins- endotoxin under the form of a parasporal crystal. They are specific in their lethal activity
against different insect pests and not harmful to mammals, birds or beneficial insects. For this reason, Bt is being
exploited as an alternative to chemical pesticides.
Initial results in laboratory have shown that municipal
wastewater sludge can support the growth of Bt and produce spore and -endotoxins.The toxicity of the
spores and endotoxins were evaluated on spruce budworm 3rd instar larvae. The entomotoxicity produced
by different stains of Bt using wastewater sludge as growth media was higher (50-75 billion IU/gallon) as
compared to the entomotoxicity produced using soy based commercial growth media (30-48 billion
IU/gallon).
However, before this process can be successful, process optimization studies to develop scale-up criteria
followed by pilot-scale investigations needs to be done. Therefore, the objective of this proposal is to conduct laboratory
studies followed by pilot-scale test that will the following parameters for optimization of the growth of Bt, its spores and
the formation of -endotoxins: - Sludge characterization - Process optimization studies (sludge solids concentration,
primary versus secondary sludge, etc) - Sludge pretreatment to enhance the entomotoxicity of the spore and -endotoxin
- Different reactor strategies to enhance the biopesticide entomotoxicity in sludge medium - Development of scale-up
criteria - Stability of the sludge based biopesticide - Field application trial along with pilot plant test  

Purpose/Objective:
GENERIC RARE OBJECTIVE: The Regional Applied Research Effort (RARE) provides the Regions with a mechanism to
address near term research needs through an ORD Laboratory/Center. Any applied research project that a Region
identifies and that an ORD laboratory has the expertise to carry out will be considered if the three following conditions
are met: 1) projects must be funded through an ORD Laboratory or Center, 2) the project must fall within with defined
mission of the selected ORD Laboratory/Center, and 3) proposals must be research-oriented.  



Science Inventory Type:  Science Activity

Last Revised: 11/11/2003  

Project Start Date:   03/01/2002  

Project Completion Date (Actual/Projected):    

Web Site Address:    

For more information, contact:   National Risk Management Research Laboratory  

Email Address:   NRMRL_Comments@epa.gov
Organization:   U.S. Environmental Protection Agency
Office Of Research And Development
National Risk Management Research Laboratory
Technology Transfer And Support Division


EIMS Record ID: 72155