The Power of Information

National Drinking Water Database


California Water Service-S San Francisco Utilities - San Jose, CA

Serves 54,060 people

1,4-Dioxane

1,4-Dioxane is a stabilizing chemical in industrial solvents and an emerging groundwater pollutant from solvent recycling and plastic manufacturing; it is a probable human carcinogen.
 
This Drinking Water System
Test Days Exceeding Health GuidelinesDefinition of what this is
0 days
Test Days Exceeding Legal LimitsNumber of days in which the samples taken in that day exceed the Maximum Contaminant Level (Depending on the contaminant and its MCL, that may or may not trigger an MCL violation. Some MCLs are based on averages spanning several months to a year)
0 days
Test DaysNumber of days in which this chemical has reported results in the data we received from the State
2 days
Tests ConductedNumber of individual tests done for this contaminant
4 tests

Testing Summary

ContaminantAverage/
Maximum
Result		Health Limit
Exceeded		Legal Limit
Exceeded

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
1,4-Dioxane1,4-Dioxane is a stabilizing chemical in industrial solvents and an emerging groundwater pollutant from solvent recycling and plastic manufacturing; it is a probable human carcinogen.0 ppb
0 ppb		No
3 ppb		Legal at any levelThis is the Federal Limit. State Limits may be lower.
NOTE: Each dot in the above graph represents one month.
* Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Health Based and Legal Limits for 1,4-Dioxane

Health Based Limits for 1,4-Dioxane

StandardDescriptionLevel
One in one million (10-6) Cancer RiskThe concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 1,000,000. Source: U.S. Environmental Protection Agency.3 ppb
One in ten thousand (10-4) Cancer RiskThe concentration of a chemical in drinking water corresponding to an excess estimated lifetime cancer risk of 1 in 10,000. Source: U.S. Environmental Protection Agency.300 ppb
Children's health-based limit for 10-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic effects for up to ten days of exposure. The Ten-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.400 ppb
Children's health-based limit for 1-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for up to one day of exposure. The One-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.4000 ppb

Testing Results

Testing DateAverage
Result		Samples taken that dayNumber of Non-DetectsRange of Results
2005-02-100 ppb220 ppb
2004-11-090 ppb220 ppb