Title: INTERPRETING YOUR LAB DATA
1INTERPRETING YOUR LAB DATA
2TYPES OF LABORATORY REPORTS
- ANALYTICAL
- WHOLE EFFLUENT TOXICITY
3INFORMATION COMMON TO ALL REPORTS
- Title
- Laboratory Name
- Address, Phone, Contact
- Unique Identifier (Laboratory Control No.)
- Number of Pages
- Client Name
- Date of Receipt
4SAMPLE SPECIFIC INFORMATION
- Unique Sample Identifier
- Sample ID
- Sample Collection Date and Time
5ANALYTICAL DATA - SAMPLE
- Parameter
- Analytical Method
- Data
- Units
- Reporting Limit RL, MDL, PQL
- Date of Analysis
- Workgroup / Batch
- Analyst
6QUALITY CONTROL DATA
- Laboratory Control Sample
- Matrix Spike Sample
- Sample Duplicate
- Surrogates
- Laboratory Blank
7LABORATORY CONTROL SAMPLE
- A sample matrix, free from the analytes of
interest, spiked with verified known amounts of
analytes or a material containing known and
verified amounts of analyte. It is generally,
used to establish intra-laboratory or analyst
specific precision and bias or to assess the
performance of all or a portion of the
measurement system.
8- Frequency Minimum 1/batch
- Individual LCS is compared to the acceptance
criteria as published in the mandated test method
or based upon three standard deviations around
the mean - A LCS that is determined to be within the
criteria effectively establishes that the
analytical system is in control and validates
system performance for the samples in the
associated batch.
9- If a large number of analytes are in the LCS, it
becomes statistically likely that a few will be
outside the control limits. This may or may not
indicate that the system is out of control. - Many laboratories have established Marginal
Exceedances (ME) Limits. ME limits are between
three or four standard deviations around the mean.
10- The number of marginal exceedances allowable is
dependent upon the number of analytes in the LCS. - gt90 analytes, 5 ME
- 71-90 analytes, 4 ME
- 51-70 analytes, 3 ME
- 31-50 analytes, 2 ME
- 11-30 analytes, 1 ME
- lt11 analytes, 0 ME allowed
11MATRIX SPIKE
- A sample prepared by adding a known amount of
target analyte to a specified amount of matrix
sample. - Matrix spikes are used to determine the effect of
the matrix on recovery efficiency.
12- Theoretically, matrix spike control limits are
typically equal to or greater than laboratory
control sample limits. - If the matrix spike amount is less than four (4)
times the result in the unspiked sample, the
MS/MSD data may not represent the matrix effect.
13SAMPLE DUPLICATE
- Replicate aliquots of the same sample taken
through the entire analytical procedure. - The results from the analysis indicate the
precision of the results for the specific sample
using the method selected and are expressed as
relative percent difference (RPD). - Typically, RPD limits for sample duplicates gt RPD
limits established from LSC/MS duplicates.
14SURROGATES
- Surrogates are used most often in organic
chromatographic test methods and are chosen to
reflect the chemistries of the targeted
components of the method. - Added prior to sample preparation /extraction,
they provide a measure of recovery for every
sample matrix.
15METHOD BLANK
- A sample of a matrix similar to the batch of
associated samples that is free from the analytes
of interest and is processed simultaneously with
and under the same conditions as samples through
all steps of the analytical procedure, and in
which no target analytes or interferences are
present at concentrations that impact the
analytical results for sample analyses.
16- Goal is to have no detectable contaminants.
- Common method blank contaminates are acetone,
methylene chloride, copper, iron, and zinc.
17GENERAL GUIDANCE - BLANKS
- If the sample contains the contaminant at levels
of at least 10 times that in the blank, then the
likely contribution to the sample from the
contaminant in the laboratory environment is at
most 10. The possible contamination is
negligible
18- If the sample contains the contaminant at levels
of at least 5 times but less than 10 times the
blank result, the compound is probably present in
the sample, but the numerical result should be
considered an upper limit of the true
concentration.
19- If the sample contains the contaminant at levels
below 5 times the level in the blank, there is no
adequate means by which to judge whether or not
the sample result is attributable to laboratory
contamination. The results for that compound in
the sample then becomes unacceptable for
compliance monitoring.
20- Parameter Relationships
- CODgtBODgtTOC
- BODgt CBOD
- Total Solids TSS TDS
- TKNgtNH3N
- Total Nitrogen TKN NO3N NO2N
- Total Organic Nitrogen TKN NH3N
- OG gt TPH
- Total Analytegt Dissolved Analyte
- Cr Cr3 Cr6
21SUPPLEMENT REPORT INFORMATION
- Sample Receipt Documentation
- Case Narrative
- Data Qualifiers
22SAMPLE RECEIPT DOCUMENTATION
- Upon receipt, samples are inspected to determine
if they meet regulatory compliance. If a sample
fails to meet the requirements, the client should
be contacted for instructions. If the decision
is to proceed with the analysis, any sample
failing to meet requirements must be
appropriately flagged on the final report.
23- Temperature
- Preservation
- Holding Time
- Container Information
- Documentation (COC)
24CASE NARRATIVE
- Provides a correlation between field sample and
laboratory sample numbers - Identifies any issues with sample receipt
- Identifies extractions or analyses that are
performed out of holding times
25- Deviations from the method
- Identification of any QC failures and associated
corrective actions taken by the laboratory - Any other factors that could affect the sample
results (e.g., air bubbles in VOC sample vials,
excess headspace, multi-phasic samples, container
type or volume)
26DATA QUALIFIERS
- Data Qualifers are added by the laboratory during
the review process - Data Qualifers are applied when measurement
quality objects are not met and corrective action
is not successful or when corrective action is
not performed - They may also be applied to provided additional
information concerning the reported data
27- B Analytes are detected in the blank above the
reporting limit - J The analyte was positive the associated
numerical value is the approximate concentration
of the analyte in the sample - Q Data requires usability review due to the
exceedance of method-specific holding time,
calibration, or batch QC data associated with the
sample does not meet measurement quality
objectives - H Holding time was exceeded
- W Data is presented on an as-received-basis
28WHOLE EFFLUENT TOXICITY
29INTRODUCTION
- Permit Number
- Toxicity Testing Requirement of Permit
- Plant Location
- Name of Receiving water body
- Contract Laboratory
- Objective of Test
30PLANT OPERATONS
- Products
- Raw Materials
- Operating Schedule
- Description of waste treatment
- Schematic of waste treatment
- Retention time (if applicable)
- Volume of waste flow
- Design flow of treatment facility at time of
sampling
31Source of Effluent, Receiving Water and Dilution
Water
- Effluent Samples
- Sampling Point
- Collection dates and times
- Sample Collection method
- Physical and chemical data
- Mean daily discharge on sample collection date
- Lapsed time from sample collection to delivery
- Sample temperature when received at laboratory
32- Receiving Water Samples
- Sampling point
- Collection date and time
- Sample collection method
- Physical and chemical data
- Streamflow
- Sample temperature when received at lab
- Lapsed time from sample collection to delivery
33- Dilution Water Samples
- Source
- Collection dates and times
- Pretreatment
- Physical and chemical characteristics
34TEST METHOD
- Toxicity test method used
- Endpoints of test
- Deviation from reference method
- Date and time test started
- Date and time test terminated
- Type and volume of test chambers
35- Number of organisms per test
- Number of replicate test chambers per treatment
- Acclimation of test organisms
- Test temperature
- Specify if aeration was needed
- Feeding Frequency, and amount and type of food
- Specify if pH control measures were implemented
36TEST ORGANISMS
- Scientific name
- Age
- Life stage
- Source
37QUALITY CONTROL
- Reference toxicant used routinely
- Date and time of most recent reference toxicant
test, test results, and current control chart - Dilution water used in reference toxicant test
- Results (NOEC or where applicable, LOEC, LC50,
EC50, IC25 and/or IC50) - Report Percent Minimum Significant Difference
(PMSD) calculated for sublethal endpoints
determined by hypothesis testing in reference
toxicant test - Physical and chemical methods used.
38RESULTS
- Provide raw toxicity data in tabular form,
including daily records of affected organisms in
each concentration (including controls) and
replicate, and in graphical form (plots of
toxicity data) - Provide table of LC50s, NOECs, IC25, IC50, etc
(as required in applicable NPDES permit) - Indicate statistical methods used to calculate
endpoints
39- Provide summary table of physical and chemical
data - Tabulate QA data
- Provide percent minimum significant differences
(PMSD) calculated for sublethal endpoints. - Relationship between test endpoints and permit
limits - Actions to be taken (if any)
40GLOSSARY
- Effect Concentration (EC) is a point estimate of
the toxicant concentration that would cause an
observable adverse effect in a given percent of
the test organisms. EC25 is a point estimate of
the toxicant concentration that would cause an
observable adverse effect in 25 percent of the
test organism
41- Inhibition Concentration (IC) is a point estimate
of the toxicant concentration that causes a
percent reduction in a non-lethal biological
measurement (reproduction and growth), calculated
from a continuous model. IC25 is a point
estimate of the toxicant that would cause a 25
reduction in a non-lethal biological measurement. - LC50 (lethal concentration, 50) is the toxicant
or effluent concentration that would cause death
in 50 percent of organisms.
42- Lowest Observed Effect Concentration (LOEC) is
the lowest concentration of an effluent or
toxicant that results in adverse effects on the
test organisms. - No Observed Effect Concentration (NOEC) is the
highest test concentration of an effluent or
toxicant that causes no observable adverse effect
on the organism - Percent Minimum Significant Difference (PMSD)
allows comparison of different tests and
represents the smallest significant difference
from the control as a percentage of the control
mean that can be measured.
43GUIDANCE FOR REVIEWING BIOMONITORING REPORTS
44- Were all samples chilled to 4oC during and/or
immediately after collection and maintained at
just above freezing. - When reviewing the holding times the maximum
holding time of effluents is 36 hours and samples
should not be used for renewals if older than 72
hours.
45- Was the dilution series used in the test as
specified in the permit? - Does the laboratory have your latest permit?
- Fathead Minnows tests use to be a series of 10
minnows /4 concentrations. New permits now have
8 minnows / 5 concentrations. - Was the DO acceptable for the test gt4 but lt9?
46- Was chlorine present in the receiving water ?
- Was the sample brought to the correct temperature
prior to starting the analysis? - Was the control and sample handled in exactly the
same manner. (Example Treated for the same
interferences (UV / antibiotic)? - Was the critical dilution reported the same as
that listed in the permit?
47- Was the Coefficient of Variation (CV) in the
control and the critical dilution lt40. - Fathead Survival in control must be at least
80. The average dry weight per surviving control
larvae at the end of the test must equal or
exceed of 0.25 mg. - Ceriodaphnia dubia Test result acceptable, at
least 80 of all control organisms must survive,
and 60 of surviving control females must produce
at least three broods, with an average of 15 or
more young per surviving female.
48VARIABILITY CRITERIA FOR SUBLETHAL HYPOTHESIS
(Upper and Lower PMSD)
- Fathead Minnow 12-30
- Ceriodaphnia dubia 13-47
49CONTROL (CV) RANGECOEFFICIENTS OF VARIATION
- Fathead 3.5 to 20 Minnow (0.035-0.2)
- Ceriodaphnia 8.9 to 42
- dubia (0.089 to 0.42)