Notice of Availability of Acute Notification Level Recommendations for Four Cyanotoxins in Drinking Water
Notice of Availability of Acute Notification Level Recommendations for Four Cyanotoxins in Drinking Water
The Office of Environmental Health Hazard Assessment (OEHHA) has submitted to the State Water Resources Control Board (”Water Board”) acute notification level (NL) recommendations for four cyanotoxins as follows:
| Cyanotoxin | Recommended Acute NL (up to 1 day) |
Health Effect(s) | Peer-Reviewed Study |
|---|---|---|---|
| Anatoxin-a | 8 µg/L* | Neurotoxicity | Fawell et al. (1994, 1999) |
| Microcystins | 3 µg/L | Liver damage | Chernoff et al. (2021) |
|
Cylindrospermopsin |
3 µg/L |
Liver & kidney cell death |
Bazin et al. (2010) |
| Saxitoxins | 0.5 µg/L | Neurotoxicity | EFSA (2009) |
* µg/L means microgram per liter, a water concentration equivalent to a part per billion.
Cyanotoxins are toxins produced by cyanobacteria, also known as blue-green algae, during algal blooms. These acute NL recommendations represent the recommended maximum concentrations that people can consume over a 24-hour period. They are supplementary to the short-term (up to one month or three months) NL recommendations provided to the Water Board on May 3, 2021. The acute NL recommendation for saxitoxins updates the value previously submitted to the Water Board. The acute NL recommendations memorandum for the four cyanotoxins is available for download below, and links to access the peer-reviewed studies for their derivation can be found in the references section of that document.
Notification levels are health-based advisory levels established by the Water Board’s Division of Drinking Water (DDW) for chemicals that lack drinking water regulatory standards (maximum contaminant levels, or MCLs). When chemicals are found at concentrations greater than their NLs, certain requirements and recommendations apply.
If you would like to receive further information on this announcement or have questions, please contact Hermelinda Jimenez at PHG.Program@oehha.ca.gov or at (916) 324-7572. Written inquiries can also be addressed to:
Pesticide and Environmental Toxicology Branch
CalEPA Office of Environmental Health Hazard Assessment
P.O. Box 4010, MS-12B
Sacramento, California 95812-4010
Attention: PHG Program