MADISON , Wisconsin ,
January 20, 2003 (ENS) - Researchers in the U.S. and
Pakistan have identified a group of microorganisms
that can break down a common toxic pesticide, endosulfan.
Detoxifying pesticides through biological means is
receiving attention as an alternative to existing
methods, such as incineration and landfill, which
are not sufficient for large, contaminated sites.
Researchers from the University of California at Riverside
and the University of Agriculture , Faisalabad , Pakistan
, have identified specific microorganisms, which can
breakdown the toxicity of endosulfan. By identifying
microorganisms to degrade endosulfan, these researchers
were able to reduce the toxic residues in the soil.
The results of this study are published in the January-February
issue of the "Journal of Environmental Quality."
"Pollutants can be degraded by microorganisms
when they use the toxin as a carbon and energy source,"
said project leader William Frankenberger of UC-Riverside.
"We have been successful in isolating two strains
that have immense potential for endosulfan degradation."
Endosulfan, classified as an organochlorine - the
same family as DDT - is registered for use as a pesticide
on 60 U.S. crops. Its residues have been found in
the atmosphere, soils, sediments, surface and ground
waters, and food.
It is one of the most commonly detected pesticides
in U.S. water, found in at least 38 states, and is
rated by the U.S. Environmental Protection Agency
as a Category 1 pesticide with "extremely high
acute toxicity." Endosulfan affects the central
nervous system, kidney, liver, blood chemistry and
parathyroid gland and has reproductive, teratogenic
and mutagenic effects. Total average annual use of
endosulfan is estimated at about 1.38 million pounds
of the active ingredient. Endosulfan and its breakdown
products are persistent in the environment, entering
the air, water, and soil during the pesticide's use
The results of this work suggest these novel strains
of microorganisms are a valuable source of endosulfan
degrading enzymes and may be used for the detoxification
of endosulfan in contaminated soils, wastedumps, water
bodies, industrial effluents and unused or expired
stockpiles of the pesticide.
Source: (AmeriScan: January 20, 2003 - Environment