B09_140G0221R0024-4_Attch_2_QandAs_01-08_0004.docx

Solicitation 140G0221R0024 Amendment 0004 Attachment 2 Questions and Answers 01 though 08

1. What are the QAQC requirements for this work? The cited references are missing QAQC protocols required to achieve quality quantitative data (e.g. standard addition, curve interpolation requirements, method validation, duplicates, method blanks/method spiked blanks). Or is this work qualitative in nature?

Quantitative analyses are needed. Blank, laboratory-fortified blank, laboratory-fortified sample matrix, and duplicate samples are all required for ELISA and LC/MS/MS analyses. All ELISA samples must be run in duplicate and a minimum of 20% of all LC/MS/MS samples must be run in duplicate; a CV of 15% or less between sample duplicates is required. Duplicate samples not meeting this requirement must be rerun. Blank samples must not have concentrations greater than ½ of the minimum reporting level. Laboratory-fortified blank and sample matrix recovery must be greater than 60% and less than 140%. All ELISA analyses must follow QA/QC requirements of EPA Method 546 to accept or reject a run.

Contractor shall include their quality control plan for sample control and analysis including description of analysis method. To ensure continuity of data across our multi-year projects, contractors who have not previously provided toxin analysis for our projects may be required to analyze up to 3 blind samples as part of the bid process and at the contractor’s expense. Successful contractors shall be within +/- 20% standard deviation of past analysis of the same sample in order to be awarded.

2. Why are the HPLC column and MS systems listed vendor specific? Would the USGS accept alternatives?

The USGS will consider alternatives. If the contractor uses systems other than those listed, the vendor and model of the HPLC and MS systems must be included with their bid.

3. Why is homoanatoxin listed but not dihydroanatoxin? Both standards are commercially available and are found in nature, with the latter becoming more of a prevalent issue.

Homoanatoxin-a is required for project continuity and comparison to historical sample results. Future work may include dihydroanatoxin.

4. Why are the majority of commercially available microcystins missing from the bid? We only see 4 listed in the cited reference, which would could result in under-reporting.

The desired microcystins for LCMSMS analysis include: Microcystin-RR, Microcystin-YR, Microcystin-LR, Microcystin-LA, [Dha7]MC-LR, Microcystin-LF, Microcystin-LY, Microcystin-WR, Microcystin-HilR, Microcystin-HtyR, and Microcystin-LW, based on analyses of on-going projects.

5. Can the analyses be split up into more analytical runs to achieve more robust quantitative data? This would deviate from the cited methods.

It will be acceptable to split the analyses into more analytical runs.

6. Why are the injection volumes listed for HPLC methods? Can these be modified to achieve more robust/reproducible data?

The contractor shall measure polar toxins (i.e. cylindrospermopsin, anatoxin-a, etc) in 15 μL injections using LCMSMS with electrospray ionization and hydrophilic interaction chromatography. The contractor shall measure less polar cyanotoxins (i.e. nodularins, microcystins, etc) in 20 μL injections using LCMSMS with electrospray ionization. These requirements can be modified to achieve more robust data. Contractor must supply the USGS with details of any modifications.

7. How were the minimum reporting levels (MRL) for ELISA determined? It appears to be the lowest calibrator for the respective kits, but the levels do not reflect SPATT specific methodologies. Please clarify.

The minimum reporting limits are based on kits provided by Abraxis, Inc. For project continuity, use of ELISA kits manufactured by other vendors will not be considered.

8. What are the ‘quality control checks’ referenced in the final statement of the technical requirements? They appear to be ELISA specific in nature, but this is not clear.

Required QA/QC as outlined above and based on the quality control plan the contractor provides to USGS. The contractor shall notify USGS regarding any samples that do not pass quality control checks even after sample reruns.