The Power of Information

National Drinking Water Database

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

Serves 54,060 people


o-Xylene is a petroleum-derived solvent used in the printing, rubber, and leather industries; it is also used as a cleaning agent, a thinner for paint, and an ingredient in paints and varnishes.
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
47 days
Tests ConductedNumber of individual tests done for this contaminant
183 tests

Testing Summary

Health Limit
Legal Limit

Testing History

-Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
o-Xyleneo-Xylene is a petroleum-derived solvent used in the printing, rubber, and leather industries; it is also used as a cleaning agent, a thinner for paint, and an ingredient in paints and varnishes.<0.01 ppb
0.35 ppb
10000 ppb
10000 ppb
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 o-Xylene

Health Based Limits for o-Xylene

Maximum Contaminant Limit (MCL)The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.10000 ppb
Maximum Contaminant Limit Goal (MCLG)A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.10000 ppb

Testing Results

Testing DateAverage
Samples taken that dayNumber of Non-DetectsRange of Results
2009-03-030 ppb660 ppb
2009-02-040 ppb440 ppb
2009-01-060 ppb330 ppb
2008-12-040 ppb330 ppb
2008-11-040 ppb330 ppb
2008-10-020 ppb770 ppb
2008-09-080 ppb330 ppb
2008-08-060 ppb330 ppb
2008-07-080 ppb770 ppb
2008-06-030 ppb330 ppb
2008-05-150 ppb330 ppb
2008-04-220 ppb110 ppb
2008-04-100 ppb770 ppb
2008-03-190 ppb330 ppb
2008-03-110 ppb110 ppb
2008-02-200 ppb330 ppb
2008-01-290 ppb110 ppb
2008-01-090 ppb660 ppb
2007-12-260 ppb110 ppb
2007-10-040 ppb660 ppb
2007-07-130 ppb660 ppb
2007-04-040 ppb660 ppb
2007-01-110 ppb660 ppb
2006-10-040 ppb660 ppb
2006-07-120 ppb660 ppb
2006-04-050 ppb660 ppb
2006-01-100 ppb660 ppb
2005-10-260 ppb660 ppb
2005-09-280 ppb110 ppb
2005-07-270 ppb220 ppb
2005-07-190 ppb660 ppb
2005-06-160 ppb330 ppb
2005-06-150 ppb330 ppb
2005-04-210 ppb330 ppb
2005-04-180 ppb330 ppb
2005-01-190 ppb660 ppb
2004-11-300 ppb660 ppb
2004-09-080 ppb550 ppb
2004-07-270 ppb220 ppb
2004-06-090 ppb330 ppb
2004-05-260 ppb550 ppb
2004-05-110 ppb110 ppb
2004-04-200 ppb110 ppb
2004-03-300 ppb110 ppb
2004-02-250.35 ppb210 to 0.7 ppb
2004-02-110 ppb550 ppb
2004-01-290 ppb330 ppb