United States
Environmental Protection
Agency
EPA'540/MR-95/514
August 1995
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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Demonstration Bulletin
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POP Immunoassay Technologies
i
Penta RISc by Ensys Inc., Penta RaPID by Ohmicron Corp.,
EnviroGard by Millipore \
Technological Description: The objectives of this dem-
onstration were to test these field screening technologies for
accuracy and precision in detecting Pentachlorophenol (PCP)
levels in soil and water by comparing their results with those of a
confirmatory laboratory. The three immunoassay technologies
were:
• EnviroGard,
• Penta RaPID Assay, and
• Penta RISc Test System.
The demonstration took place in Morrisville, NC where NERL-
CRD and National Risk Management Research Laboratory
(NRMRL) combined logistical and support efforts. The demon-
stration plan called for 98 soil samples, 53 samples from the
Kippers Company in Morrisville, NC, and 45 soil samples from
the Winona Post in Winona, MO.
An immunoassay test kit uses enzyme-linked immunosorbent
assays (ELISA) to create a color change. A portable spectropho-
tometer measures the color intensity, which is inversely propor-
tional to PCP concentrations in the sample.
The Penta RISc and Envirogard Tests can both analyze for PCP
in soil and water samples. They both use the walls of test tubes
as the substrate for the polyclonal antibodies that are the basis
for the test. When target analytes are introduced to the antibody
coated test tube they occupy antibody binding sites in proportion
to their concentration. An enzyme conjugate is introduced to
compete with the target analyte for binding sites, and a chro-
mogen which reacts with the enzyme to produce color complete
the ELISA test.
The Penta RaPID Assay, also uses an ELISA conjugate to
compete with PCP in an environmental sample. The antibody
binding substrate is magnetic particles attached inside the test
tube. In addition to soil and water this assay is applicable to crop
and food samples.
Waste Applicability: ELISA systems are most applicable
to sites where PCP is a known contaminant and where large
concentrations of other chemicals are not present in the samples.
The potential limitation of ELISA systems is that their results may
not always agree with results from the analysis of the same
sample by EPA approved methodologies. The principal advan-
tage of the ELISA technology, which all three technologies used,
is that it is very specific to PCP. The technology was found to be
easy to operate by individuals with some prior analytical labora-
tory experience.
Demonstration Results: Examination of the Penta RISc
Test System revealed 83 correct results and 31 incorrect results.
The majority of the incorrect results were false positives. This
technology does not produce quantitative data. Overall, the tech-
nology was found not tcj be accurate when compared to Level 3
data, but it can produce I Level 2 or Level 1 data.
I
Examination the Penta RaPID Assay revealed that the technol-
ogy did not meet the criteria for Level 3 accuracy, but it can
produce Level 2 or Level 1 data. This technology can produce
quantitative data.
The EnviroGard PCP Test Kit produced false negative results
when concentrations of 'PCP were greater than 1,000 ppm. The
developer has modified the technology. In a letter to EPA, the
developer said: "We believe that, based on the knowledge gained
from the demonstration, we have been able to make significant
improvements in our product." The SITE Program has not yet
reevaluated the kit since the modifications.
An Innovative Technology Evaluation Report (ITER) describing
the complete demonstra.tion will be available in late 1995.
Printed on Recycled Paper
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Acknowledgment: This Bulletin was prepared by the U.S. For Further Information:
Environmental Protection Agency, Office of Research and Devel-
opment, National Risk Management Research Laboratory, Cin- EPA Project Manager:
Cinnati, OH 45268. Jeanette M. Van Emon
Characterization Research Division
NERL
Las Vegas, NV 89193-3478
702-798-2154
United States
Environmental Protection Agency
National Risk Management Research Laboratory (G-72)
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
EPA/540/MR-95/514
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
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