Title: Weighing Field Trial and Processing Trial Residue Samples
Issue/ Question:Do the scales/balances used to establish estimated weights of field and
processing trial residue samples need to be maintained in strict adherence to
GLP?
Background: In
two EPA inspections of IR-4 field test sites in year 2003, auditors noted that
the "facility failed to maintain under GLP the scale used to determine field
residue sample weights," and in both cases this was recorded as a finding by
the agency inspectors. This issue was
not noted in a number of other recent EPA inspections at facilities where the
weighing of residue samples was not completed under strict adherence to GLP.
IR-4
protocols generally require a "minimum" sample weight (and usually "preferably
not more than." a certain weight) of the crop.
In Part 7B in the FDB, the "approximate weight" of each sample is
recorded. These protocol and FDB prompts
regarding sample weights are based on EPA "recommended" sample weights in
Attachment 8 of the EPA Residue Chemistry Test Guidelines (OPPTS 860.1500, Crop
Field Trials [Updated]). Additionally,
IR-4 sometimes adjusts these EPA recommendations based on the needs of the laboratory
that will analyze the samples.
2) Part 1C
of field data books will include a statement to be checked if scales/balances
used to establish estimated weights of field and processing trial residue
samples were maintained in strict adherence to GLP.
3) In Part
7B of field data books, FRD will be prompted to answer "Yes" or "No" to the
question "Was a GLP-maintained scales/balance used to determine residue sample
weights?"
4)
Compliance statements in IR-4 final study reports will consistently reflect
this IR-4 policy.
NOTE: This IR-4 policy does not preclude the use of
scales/balances (to establish estimated residue sample weights) that are
maintained in strict adherence to GLP.
(This advisory expands on this sample weight topic in
Items 56 and 94 in the
San Antonio Results Document, dated