HomeMy WebLinkAboutWood E&I MC Report 230105 (Elsinore)_Redacted
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Sample Preparation
Water Sample Freeze-Thaw
The samples were inverted for 60 seconds to mix. A subset of each sample was transferred to a
15 mL vial. Three freeze-thaw cycles were employed prior to additional sample preparation and
subsequent analysis.
Analytical Techniques
Enzyme-Linked Immunosorbent Assay (ELISA)
MCs/NODs
A microcystins/nodularins Adda ELISA (Abraxis) was utilized for the quantitative and sensitive
congener-independent detection of Adda MCs/NODs (US EPA Method 546 & Ohio EPA DES
701.0). The current method reporting limit is 15 ng/mL (ppb) based on kit sensitivity (0.75
ng/mL), minimum dilution factor (100X), and initial demonstration of capability.
Qualifier Flag
CL Analytical result is estimated due to ineffective quenching.
J Analyte was positively identified; the associated numerical value is estimated.
PT The reported result is estimated because the sample was not analyzed within required holding time.
B Analytical result is estimated. Analyte was detected in associated reagent blank as well as the samples.
E Analytical result is estimated. Values achieved were outside calibration range.
N Spiked sample control was outside limits
T The reported result is estimated because the sample exceeded temperature threshold when received
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Quality Control
Table 2: Adda MC-ELISA Quality Control Value Table
Date Analyzed: 10-Jan-23 Requirement Pass/Fail
R2 value: 0.999 ≥0.98 PASS
%CV STDs: 0.3-5.9% ≤15% PASS
LFB (1 ppb) recovery: 97% ±40% True Value PASS
%CV LFB: 2.9% ≤20% PASS
Low CCC (0.15 ppb) recovery: 80% ±50% True Value PASS
LRB <0.08 <0.08 PASS
Table 3: Adda MC-ELISA Quality Control Value Table
Date Analyzed: 11-Jan-23 Requirement Pass/Fail
R2 value: 0.997 ≥0.98 PASS
%CV STDs: 1.1-10.0% ≤15% PASS
LFB (1 ppb) recovery: 88% ±40% True Value PASS
%CV LFB: 5.8% ≤20% PASS
Low CCC (0.15 ppb) recovery: 90% ±50% True Value PASS
LRB <0.08 <0.08 PASS
Results
Table 4: Raw ELISA Data including the sample identification, analyte, date analyzed,
interpolated values 1 and 2, the dilution factor, %CV of the absorbance values, and average final
concentration (ng/mL; ppb).
Sample Date Value 1 Value 2 Dilution Average
Sample ID Type Analyte analyzed (ng/mL) (ng/mL) Factor %CV (ng/mL)
Launch Pointe Boat Ramp FS MCs/NODs 1/10/2023 0.19 0.16 100 2.5 17.5
Launch Pointe Boat Ramp FS MCs/NODs 1/11/2023 0.41 0.45 50 2.3 21.5
Elsinore West Marina FS MCs/NODs 1/10/2023 0.39 0.34 100 2.9 36.5
Elsinore West Marina FS MCs/NODs 1/11/2023 0.94 0.86 50 3.2 45.0
Elm Grove Beach FS MCs/NODs 1/10/2023 0.07 0.16 100 6.5 11.5
Elm Grove Beach FS MCs/NODs 1/11/2023 1.25 1.10 10 4.5 11.8
Elm Grove Beach FS MCs/NODs 1/11/2023 0.22 0.20 50 1.5 10.5
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Summary of Results
Table 5: Summary of results in ng/mL
MCs/NODs
Sample ID (ng/mL)
Launch Pointe Boat Ramp 19.5
Elsinore West Marina 40.8
Elm Grove Beach 11.3
MRL (ng/mL): 15
Analyst Initials: AF
Date Analyzed: 1/10/2023 & 1/11/2023
Interpretations:
The levels of Adda MCs/NODs detected in the samples are above the current ‘Draft EPA
Recommended Value for Recreational Criteria and Swimming Advisory,’ at 8.0 ng/mL (ppb)
total microcystins. The WHO recreational guidance value for microcystin is currently 24 ng/mL
(ppb) (World Health Organization (WHO), 2020a).
Submitted by:
Mark T. Aubel, Ph.D.
Lab Director
Date: January 11, 2023
The results in this report relate only to the samples listed above.
This report shall not be reproduced except in full without written approval of the laboratory.