FROM THE BENCH
Five Years to an EPA-Approved Cyanide Method:
How Maine Achieved Success
By Jim Eaton, PhD, Chemist II, Maine Health and Environmental Testing Laboratory
In early 2004, Maine’s Health and
Environmental Testing Laboratory (HETL)
joined the US Centers for Disease Control
and Prevention’s (CDC’s) Laboratory
Response Network for Chemical Threats
(LRN-C), and cyanide in blood was the first
method that Maine scientists brought up.
They trained at CDC’s National Center for
Environmental Health (NCEH) laboratory
in Atlanta. After returning home, HETL
scientists speculated they should be able
to analyze cyanide in drinking water by
the same method, which would make
analysis much easier, quicker and more
environmentally friendly than the
distillation method then in use.
HETL tried several tests with good
recovery and reasonable results for
spiked samples and then initiated the
validation process for a new drinking
water method. After internet research,
HETL scientists determined they
needed to submit a proposal to the US
Environmental Protection Agency (US
EPA) for the method. In June 2005, HETL
submitted the initial validation plan to
the US EPA Region 1 laboratory in Boston.
The plan was referred to the US EPA Office
of Ground Water and Drinking Water in
Cincinnati (EPA Cincinnati).
In March 2007, EPA Cincinnati provided
a validation plan to meet the US EPA
request of a three-laboratory study
completed on several different types of
samples. At this point, membership in
the LRN-C proved invaluable because
LRN-C laboratories were running blood
cyanide and thus had the expertise and
equipment to quickly participate in a
multi-lab validation of the proposed
drinking water method. HETL scientists
asked their counterparts in Michigan and
Vermont to participate, and they accepted.
Personal contacts with state and federal
scientists developed at biannual LRN-C
meetings likely contributed to members’
willingness to participate in the study.
PublicHealthLabs
@APHL
During the validation study, laboratories in Maine, Vermont and Michigan
analyzed seven replicates at two spiking levels in deionized water.
During the validation study, laboratories
in Maine, Vermont and Michigan analyzed
seven replicates at two spiking levels in
deionized water. Samples were spiked
at 50 parts per billion (ppb) and at the
US EPA Maximum Contaminant Level
(MCL) for cyanide of 200 parts per billion
(ppb). To assess interferences, US EPA
recommended samples of high ionic
strength and high total organic carbon
(TOC). HETL used a salt mixture for the
ionic strength samples and took high
TOC samples that were submitted to
its laboratory for routine testing. HETL
then aliquoted these and sent them to
Michigan and Vermont.
HETL compiled the data from the
three laboratories and, in January 2008,
sent it to EPA Cincinnati for review.
After making several minor method
modifications, HETL was notified by EPA
that the method had been accepted in
June 2008. In August 2009, the method
was published in the Federal Register
APHL.org
under US EPA drinking water method
number ME355.01, meaning that the
method was accepted as valid for any
laboratory running this type of analysis.
The five-year journey from initial concept
to final acceptance and publication was
completed at last. Success with US EPA
could not have been achieved without
the support of CDC NCEH and the
willing participation of LRN-C member
laboratories. HETL thanks all who assisted
in this long journey, as it was truly a team
effort. n
DIGITAL EXTRA:
Would your laboratory like to conduct a
multi-laboratory validation study of one
of its methods for submission to EPA?
Contact Jennifer Liebreich at
[email protected]
Winter 2019 LAB MATTERS
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