[Federal Register Volume 80, Number 116 (Wednesday, June 17, 2015)]
[Pages 34637-34638]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-14936]



[EPA 820R15100, EPA 820R15101, EPA 820R15102, EPA 820R15103, EPA 
820R15104; EPA-815R15010; FRL-9929-28-OW]

Availability of Health Effects Support Documents and Drinking 
Water Health Advisories for Cyanobacterial Toxins; and a Support 
Document Containing Recommendations for Managing Cyanotoxins in 
Drinking Water

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of availability.


SUMMARY: The Environmental Protection Agency (EPA) announces the 
release of Ten-Day Health Advisories (HAs) for two cyanobacterial 
toxins, microcystins and cylindrospermopsin. EPA also announces the 
release of Health Effect Support Documents (HESDs) for three 
cyanobacterial toxins: Microcystins, cylindrospermopsin, and anatoxin-
a. The HESDs constitute a comprehensive review of the published 
literature on the chemical and physical properties of these toxins, the 
toxin synthesis and environmental fate, occurrence and exposure 
information, and health effects. The HESDs are used to develop HAs. 
Based on the reported occurrence, toxicology, and epidemiology data, 
EPA found there are adequate data to develop HAs for microcystins and 
cylindrospermopsin, but inadequate data to develop an HA for anatoxin-
a. EPA's HAs provide states, drinking water utilities and the public 
with information on health effects of microcystins and 
cylindrospermopsin, analytical methods to test for cyanotoxins in water 
samples, and treatment technologies to remove

[[Page 34638]]

cyanobacterial toxins in drinking water. Additionally, EPA announces a 
support document for states and utilities to assist them as they 
consider whether and how to manage cyanobacterial toxins in drinking 
water. The recommendations in this document are intended to assist 
public drinking water systems (PWSs) manage the risks from 
cyanobacterial toxins in drinking water, including information and a 
framework that PWSs can consider in their cyanotoxin risk management 

FOR FURTHER INFORMATION CONTACT: For information regarding the HAs or 
HESDs: Lesley D'Anglada, Office of Water, Health and Ecological 
Criteria Division (4304T), Environmental Protection Agency, 1200 
Pennsylvania Avenue NW., Washington, DC 20460; telephone number: (202) 
566-1125; email address: [email protected]. For information 
regarding recommendations for cyanotoxin management in drinking water: 
Hannah Holsinger, Office of Water, Office of Ground Water and Drinking 
Water (4607M), Environmental Protection Agency, 1200 Pennsylvania 
Avenue NW., Washington, DC 20460; telephone number: (202) 564-0403; 
email address: [email protected].


I. General Information

A. How can I get copies of this document and other related information?

    1. Electronic Access. You may access this Federal Register document 
electronically from the Government Printing Office under the ``Federal 
Register'' listings at FDSys (http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR). The Health Effects Support 
Documents and the Health Advisories for the cyanobacterial toxins are 
available on EPA's Web site at http://water.epa.gov/drink/standards/hascience.cfm. The Recommendations for Public Water Systems to Manage 
Cyanotoxins in Drinking Water document is available on EPA's Web site 
at http://www2.epa.gov/nutrient-policy-data/guidelines-and-recommendations.

II. What are cyanobacterial toxins and how are they produced?

    Algae and cyanobacteria are natural components of fresh water; 
however, under favorable conditions, they can rapidly multiply causing 
``blooms.'' Some cyanobacterial species can produce toxins 
(cyanotoxins) at levels that may be of concern for human health. These 
cyanobacterial toxins are of particular concern because of their 
potential impacts on drinking water and the potential to affect human 

III. What are EPA's Health Advisories?

    Under the Safe Drinking Water Act, EPA may publish Health 
Advisories (HAs) for contaminants that are not subject to any national 
primary drinking water regulation. 42 U.S.C. 300 g-1(b)(1)(F). EPA 
develops HAs to provide information on the chemical and physical 
properties, occurrence and exposure, health effects, quantification of 
toxicological effects, other regulatory standards, analytical methods, 
and treatment technology for drinking water contaminants. HAs describe 
concentrations of drinking water contaminants at which adverse health 
effects are not anticipated to occur over specific exposure durations 
(e.g., one-day, ten-days, several years, and a lifetime). HAs also 
contain a margin of safety to address database uncertainties. HAs serve 
as informal technical guidance to assist federal, state and local 
officials, as well as managers of public or community water systems in 
protecting public health when emergency spills or contamination 
situations occur. They are not regulations and should not be construed 
as legally enforceable federal standards. HAs may change as new 
information becomes available.

IV. Information on EPA's Ten-Day Health Advisories for the 
Cyanobacterial Toxins, Cylindrospermopsin and Microcystins

    Today, EPA is making available the HA values for the cyanobacterial 
toxins microcystins and cylindrospermopsin. EPA recommends 0.3 
micrograms per liter for microcystins and 0.7 micrograms per liter for 
cylindrospermopsin as levels not to be exceeded in drinking water for 
bottle-fed infants and young children of pre-school age. For school-age 
children through adults, the health advisory values for drinking water 
are 1.6 micrograms per liter for microcystins and 3 micrograms per 
liter for cylindrospermopsin. The HA values are based on exposure for 
ten days.

V. Information on EPA's Support Document To Assist States and Utilities 
in Managing Cyanobacterial Toxins

    EPA also announces the release of a cyanotoxin management document 
that is a companion to the HAs for microcystins and cylindrospermopsin. 
The document is intended to assist PWSs that choose to develop system-
specific plans for evaluating their source waters for vulnerability to 
contamination by microcystins and cylindrospermopsin. It provides 
information and a framework that PWSs and others (as appropriate) can 
consider to inform their decisions on managing the risks from 
cyanotoxins to drinking water.

    Dated: June 10, 2015.
Kenneth J. Kopocis,
Deputy Assistant Administrator, Office of Water.
[FR Doc. 2015-14936 Filed 6-16-15; 8:45 am]