1. PERCHLORATE Background and History Occurrence Toxicity
Kevin Mayer
U.S. EPA, Region 9
Background and History
Occurrence
Toxicity
Regulatory Status

2. Perchlorate PROBLEM STATEMENTS
Is this Chemical in the Environment ? (Is there an EXPOSURE ?)
If so, should we worry about this ?
(Define the TOXICITY)
With this information, we can start to Make REGULATORY DECISIONS

3. Perchlorate CHEMISTRY Dissolves and Moves Like Salt in Water
Highly Soluble, Mobile, Stable
Hard to Treat by Usual Methods
Hard to Detect Below 400 ppb, until March 1997 4

5. Perchlorate
HISTORY
First Manufactured at Niagara Falls, Eventually at 9 Locations, now only in Cedar City, UT
1950s – Used as Human Drug
1980s - Aware of Perchlorate Use at CA and NV Superfund Sites
1990s - Aerojet in Rancho Cordova
Discovered at > 1000 ppb in Groundwater

6. Perchlorate HISTORY 1992 and 1995 - EPA Provisional Reference Dose
at ppb
Analytical Breakthrough to 4 ppb
Region 9 Requests Manufacturer’s
Information
1997 and Region 9 Alerts EPA
HQ, Regions, and States

7. Perchlorate USES 90% Manufactured for Solid Rocket Fuel Explosives
Fireworks, Flares and Smoke Markers
Reported in Nitrate Fertilizer from Chile

9. Perchlorate SHIPMENTS Manufacturer's Information
from Region 9 Requests
About 240 Facilities
40+ States
Information Not Available Before 1970s

10. PERCHLORATE MANUFACTURERS and USERS
APRIL, 2003

11. Perchlorate OCCURRENCE CALIFORNIA Detections Reported in 35 States
AL, AZ, AR, CO, FL, GA, IA, IL, IN, KS, LA, MD, MA, MI, MN, MS, MO, NE, NV, NJ, NM, NY, NC, OH, OK, OR, PA, SC, SD, TX, UT, VA, WA, WV and PR
CALIFORNIA
Over 6700 Water Supply Wells Tested
Detected in 350 sources, 5+ %

12. US EPA September 2004 : www.epa.gov/fedfac/documents/perchlorate.htm

13. 2002 and 2004 Average Perchlorate Concentrations
Lower Colorado River
2002 and 2004 Average Perchlorate Concentrations
In 1997, 900 pounds per day entered Lake Mead
By 2001, about 500 pounds per day
Measurable entire 300 miles to Mexico
Used by Las Vegas Los Angeles, San Diego, Phoenix and agriculture
Water supply for over 15 million people
500 ppb 150 ppb
10 ppb 7 ppb
6 ppb 4 ppb
5 ppb <4 ppb
5 ppb <4 ppb

14. U.S. EPA Region 9 PERCHLORATE RELEASES State Lead Sites
Lincoln
N E V A D A
Reno
Lake
Superfund Sites
Tahoe
Carson
City
Site Assessment Areas
Sacramento
Aerojet
Sonoma
Rancho Cordova
Colorado River Contamination
LLNL Site 300
San
Francisco
UTC
San Jose
Santa Clara
San Martin
Hollister (2)
Tulare County
Las Vegas
PEPCON
C A L I F O R N I A
BMI Kerr-McGee
A R I Z O N A
Casmalia
Vandenberg AFB
Santa Clarita
Edwards AFB
San Fernando (2)
Santa
Susanna
Rialto
NASA JPL
Redlands
San Gabriel ( 3)
San Nicholas
Chino Basin(2)
White Tanks
Phoenix
Island
Wyle
Stringfellow
Los Angeles
Corona
Goodyear
Gila River Brownfields
El Toro MCAS
U.S. EPA Region 9
Tucson
Benson Apache
June 2004 CA AZ NV-3
Davis Monthan
M E X I C O