Sampling Procedure for Harmful Algal Bloom Testing
Required Sampling Materials
- Sample bottles (amber glass with PTFE lined caps or PETG plastic bottles), min. 100 mL volume.
- Preservative (Abraxis Anatoxin-a/Saxitoxin Sample Diluent Concentrate 10X) – Optional
- Adhesive labels
- Marker with indelible ink
- Cooler with ice or ice packs
- Chain of Custody (COC) form
- Neutralizing agent (Sodium Thiosulfate and/or L-Ascorbic Acid) for chlorinated drinking water samples
- Drinking water samples containing chlorine need to be neutralized at the time of collection using Sodium Thiosulfate (100 mg/L) for microcystin/nodularin, cylindrospermopsin and saxitoxin analyses or with L-Ascorbic Acid (100 mg/L) for anatoxin-a or cylindrospermopsin analyses. Depending on the toxins to be analyzed, two bottles may be required—one with sodium thiosulfate and one with ascorbic acid.
- If the desired analysis includes toxin testing for anatoxin-a or saxitoxin, it is recommended that a concentrated preservative is added to each sample bottle before collection at a 1:10 dilution (e.g., 25 mL preservative in a 250 mL bottle). The preservative can be ordered directly from Abraxis, Inc. (T: 215-357-3911). Sample bottles can then be topped off with water and sealed. If you are only interested in microscopy, genetic analysis (QPCR), microcystin or cylindrospermopsin toxin analysis, then the preservative solution can be excluded and the bottles can be filled to the top.
- Be sure to label each bottle with indelible ink, using names consistent with the chain of custody form. On the chain of custody form indicate which analyses you would like run for each sample.
- Place the sample bottles into a cooler with ice or ice packs. Keep the samples between 4-10˚C, but do not allow them to freeze if molecular or microscopic analyses are required.
- Mail packages overnight (or deliver them in person) to Bend Genetics, LLC within five (5) days of collection. If mailing the samples, please use delivery by 10:30 AM – but not first delivery express – since we do not open until 8 AM, therefore nobody will be here to receive the package if it arrives before 8 AM. We recommend shipping in coolers (either plastic or Styrofoam) in order to maintain the sample temperature below 10˚C. Please include a return shipping label if you would like your cooler and ice packs returned.
- Please email firstname.lastname@example.org to let them know to expect your shipment. If available, please include the tracking number.
- Results will be transmitted electronically within four (4) business days of sample receipt. If you need the results sooner, rush services (by the end of the following business day) are available.
Notes for toxin analysis:
Water samples (minimum 100 mL) should be collected and stored on wet ice (4oC) out of the light. Amber glass containers with PTFE-lined caps are preferred since certain hydrophobic toxin congeners may adsorb to plastics. However, due to breakage concerns during shipping, polyethylene terephthalate glycol (PETG) containers can be used in place of glass bottles. Unless specified, we will measure the total concentration of each toxin class requested by lysing all cells in the sample and measuring the total toxin concentration. Note that once a sample has been frozen, it is only possible to determine total toxins since freeze-thawing will lyse the cells. Samples should be processed or frozen within five (5) days of collection in order to minimize toxin decay.
For SPATT (solid phase adsorption toxin tracking) analysis, after retrieval from the water body, the bags should be thoroughly rinsed in distilled or deionized water, then stored in DI water at 4oC if analysis will be conducted within one week or at -20oC for long-term storage.
For shellfish samples, customers should provide the laboratory with frozen or lyophilized tissue homogenates.
Notes for DNA analysis:
Customers can send water samples (minimum 100 mL) in glass or plastic (HDPE or PETG) bottles as described above or they can send filtered samples stored folded in microcentrifuge tubes or aluminum foil. If whole water is mailed to the lab, we will concentrate the sample onto glass fiber filters and extract total DNA from the filtered sample. Water samples must never be frozen, because upon thawing the cells will lyse and release their DNA into solution, which will not be retained by filtering. If customers choose to concentrate their own samples and send us filters, they should be mailed frozen on ice. The sample volume filtered must also be provided in order for us to accurately calculate gene copies/mL using QPCR. Please note that samples should be processed as soon as possible and within five (5) days in order to minimize cell lysis and DNA degradation.
Notes for Microscopy:
Customers can send water samples (minimum 50 mL) in glass or plastic (HDPE or PETG) bottles and we will take photographs of their contents under the microscope and report the cyanobacterial genera and their relative abundances (e.g., Oscillatoria sp. was most abundant, with a low amount of Microcystis sp. observed). Samples received by the lab within 5 days do not require any preservative if they are kept cold/refrigerated. Samples must not be allowed to freeze, because freezing will cause the cells to lyse. Microscopy is often the first step performed on samples in order to determine if cyanobacteria are present and to assess which cyanotoxins may be present based on the following table: