Laboratories and Treatment Options: Cyanobacteria and Cyanotoxin Analysis

There are several options available for cyanobacteria and cyanotoxin analysis. As the needs of each utility are unique, so will your analysis methods be.

  • In-house algae identification
  • Algae Lab – Trained phycologist can identify algae to the species level and provide numerical count of predominant algae.
  • Toxin analysis -Analysis can be performed in-house or sent to qualified laboratory.

There are benefits and limitations to every option and so it may be useful to overlap or combine methods.

Analysis Toxins Limitations Skill Level Approximate Cost per analysis
Abraxis Strips/Tube Microcystin 0.3-10ppb Cylindrospermopsin 0-10ppb Anatoxin 0-2.5ppb Strips are a qualitative – best used as a screening test for presence of toxins. Should confirm results with ELISA or LC/MS/MS Moderate In-house -$25
ELISA kit Microcystin Cylindrospermopsin Anatoxin Saxitoxins ELISA is a quantitative test – Indicates total toxin does not identify microcystin congeners Intermediate Capital cost -$25,000 In-house – $50 Lab – $125-$150
LC/MS/MS Microcystin Cylindrospermopsin EPA Method 544 & 545 quantitative – Indicates specific congeners of toxins not total toxins. It is possible to have a non-detect (microcystin) with method 544 and positive result with ELISA Advanced Lab – $250-$500

Algae identification pictures and resources, as well as links to labs that offer certified toxin analysis ELISA and LC/MS/MS, can be found in Appendix C.

Depending on the toxin results of the raw water monitoring, finished water monitoring may be required. A water system may also consider treatment train monitoring and distribution system monitoring if cyanotoxins are present in the raw water.

B. Initial Finished Water Monitoring

If cyanotoxins are detected by a Public Water System in raw water, the water system should begin finished water monitoring for the detected cyanotoxins according to the schedule in Table 5 (see Appendix C for sampling details):

Table 5: Initial Finished Water Sampling Schedule

Sample Location Sample Frequency Result – Cyanotoxins Detected* Result – Cyanotoxins Detected in Raw but Not Finished Water Result – No Cyanotoxins Detected in Raw or Finished Water
Entry point to distribution system 2 times per week Collect confirmation sample within 24 hours; if confirmed proceed with follow-up sampling per schedule below Continue raw and finished water sampling 2 times per week until cyanotoxins are not detected in raw water Continue raw water sampling 2 times per week until bloom is gone (discontinue finished water sampling)

*Report cyanotoxin analytical results to the Division of Drinking Water within 24 hours of receipt

C. Follow-up Finished Water Monitoring Frequencies after Detecting Cyanotoxins

If cyanotoxins are detected by a Public Water System in finished water, the water system should continue finished water monitoring for cyanotoxins according to the schedule in Table 6:

Table 6: Follow-up Finished Water Sampling Schedule

Detection Level in Finished Water Sample Frequency How Long? Then What?
Cyanotoxins below Health Advisory Levels for Infants and Young Children* 2 times per week Until below detection in finished water and below detection in 2 consecutive raw water samples Sample raw water 2 times per week if bloom exists; discontinue raw water sampling if bloom is gone
Cyanotoxins above Health Advisory Levels for Infants and Young Children* Daily Until <0.3 μg/L (microcystins) or <0.7 μg/L (cylindrospermopsin) in 2 consecutive finished water samples, 24 hrs. apart Sample raw water 2 times per week if bloom exists; discontinue raw water sampling if bloom is gone
Cyanotoxins above Health Advisory Levels for Adults** Daily Until <0.3 μg/L (microcystins) or <0.7 μg/L (cylindrospermopsin) in 2 consecutive finished water samples, 24 hrs. apart Sample raw water 2 times per week if bloom exists; discontinue raw water sampling if bloom is gone

*0.3 µg/L for microcystins; 0.7 µg/L for cylindrospermopsin
**1.6 μg/L for microcystins; 3.0 μg/L for cylindrospermopsin

D. Acceptable Analytical Methods

A Public Water System should choose an analytical method suitable to the water being sampled and the intended use of the results. For source water and raw water monitoring, ELISA (enzyme-linked immunosorbent assay) field kits, which can provide rapid semi-quantitative results, and Immunochromatographic Strip Tests are acceptable. For finished water analyses, a laboratory certified in the use of approved analytical methods for quantifying cyanotoxins, such as ADDA specific ELISA for microcystins, should be used. Appendix D lists the acceptable analytical methods for the analysis of water samples for cyanotoxins under various circumstances.