1. Cyanotoxin Reduction Performance
May 13, 2015
DWTU Joint Committee Meeting

2. Background
Cyanotoxins are significant issue in the USA and Canada with the USEPA estimating that 50 million are at risk to exposure to cyanotoxins in the USA.
Toledo, Ohio event in August 2014 has brought this to the forefront. These events have been occurring at smaller scales for many years.
Extremely low levels of cyanotoxins can have serious acute and possibly chronic health effects.
Science of cyanotoxins has been growing and has recently reached a point where the toxicological information and analytical methods are allowing action to be taken.

3. Background
USEPA has identified three cyanotoxins as high priority and have placed them on the Contaminant Candidate List (CCL): Microcystins, Anatoxin-a, and Cylindrospermopsin.
USEPA has issued health advisory levels for Microcystins and Cylindrospermopsin.
Anatoxin-a does not have adequate toxicological information at this time to issue a health advisory level. Voluntary action levels have been set from 1 to 20 ug/L.
POU and POE treatment may provide an additional barrier of safety to the user for treated water supplies.

4. Background USEPA Health Advisory Levels
Contaminant
Bottle Fed Infants and Pre-School Children (<5 years)
School aged Children and Adults (>5 years)
(ug/L)
Microcystins
0.3
1.6
Cylindrospermopsin
0.7
3.0

5. Background
Due to the immediate need and the potential for POE and POU products to provide an additional barrier to these contaminants, NSF moved forward with the development of a DWTU Protocol.
This protocol and validation work that NSF has performed will be made available to the DWTU Joint Committee for the potential development of a Standard.

6. NSF Protocol P477 – Drinking Water Treatment Units - Cyanotoxins

7. Protocol Claims
Claims made for specific cyanotoxins: Microcystin and Cylindrospermopsin.
Anatoxin-a (and others) will be added when health effects limits are published and raw compound is available for influent challenge.
No general cyanotoxin claim at this time.
Supplemental treatment device for use on microbiologically safe waters.
Statement regarding suspended cyanobacterial cells if no cyst certification present on system.

8. Protocol Features
Influent levels set at 4 ug/L which is greater than currently reported maximum level in finished municipal drinking water.
Effluent pass/fail criteria set at most protective level (bottle fed infants and pre-school children).
Currently includes only activated carbon DWTU products but will expand to reverse osmosis and other technologies as needed.
Models NSF/ANSI Standard 53.
Test water includes elevated levels of TOC (>2 mg/L).
Treatment train concept is included.

9. Protocol Challenges
Influent levels for contaminants require significant amounts (~50 mg) which has a significant effect on test cost.
Anatoxin-a is available by synthesis, but awaits Health Advisory level (perhaps other established level could be used?).
Highly toxic compounds which will require additional precautions against splash, aerosolization, and dermal contact for concentrated solutions or powders.
Analytical methods require advanced instrumentation to achieve low level quantification (LC/MS/MS) for reduction performance.

10. Thank You for Your Attention
Questions?