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EWG's Tap Water Database — 2021 UPDATE

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MTBE

Maryland American Water Company

MTBE was used as gasoline oxygenation additive to boost the octane number. In 2005, MTBE was replaced by ethanol as a gasoline additive. MTBE causes cancers in rats.

 

79

Samples

0

Samples exceeding legal limit (MCL)

5

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20142.34 ppb187ND - 15.3 ppb
20153.98 ppb1110ND - 13.8 ppb
20166.12 ppb1611ND - 30.6 ppb
2017ND80ND
2018ND110ND
20190.0467 ppb151ND - 0.700 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 13 ppb

The EWG Health Guideline of 13 ppb for MTBE was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.

ppb = parts per billion

All test results

Date Lab ID Result
2014-01-140120003_02_244790.600 ppb
2014-02-120120003_02_24872ND
2014-02-120120003_02_24872ND
2014-02-120120003_02_24872ND
2014-02-120120003_02_24872ND
2014-02-140120003_02_24873ND
2014-02-180120003_02_24873ND
2014-03-100120003_02_25038ND
2014-04-080120003_02_25195ND
2014-05-130120003_01_25676ND
2014-05-130120003_02_25671ND
2014-06-180120003_02_259341.90 ppb
2014-07-160120003_02_263123.10 ppb
2014-08-120120003_02_265674.60 ppb
2014-09-040120003_02_0008615.3 ppb
2014-09-110120003_02_269087.20 ppb
2014-10-150120003_02_272589.50 ppb
2014-12-080120003_02_27708ND
2015-01-150120003_02_28007ND
2015-02-120120003_02_281680.700 ppb
2015-03-04283114010.700 ppb
2015-04-14286581011.000 ppb
2015-06-16290765011.90 ppb
2015-08-11299338011.30 ppb
2015-09-08300989012.20 ppb
2015-10-06E1600148501813.8 ppb
2015-10-13303123016.00 ppb
2015-11-16305555018.60 ppb
2015-12-21307636017.50 ppb
2016-01-12310048010.600 ppb
2016-02-1031164301ND
2016-03-0831416101ND
2016-04-12316022011.30 ppb
2016-05-1031993001ND
2016-05-10319920014.00 ppb
2016-05-10319919013.90 ppb
2016-06-273287771.80 ppb
2016-07-123265371.90 ppb
2016-08-093288159.50 ppb
2016-09-013318700130.6 ppb
2016-09-2033597601ND
2016-10-11334095ND
2016-11-083370026.70 ppb
2016-11-30E1700234700416.2 ppb
2016-12-143392310121.4 ppb
2017-01-1734232601ND
2017-02-1434563201ND
2017-03-1434852301ND
2017-04-1135076401ND
2017-05-0935393101ND
2017-05-0935398301ND
2017-05-3036129801ND
2017-10-31E18001764001ND
2018-05-1539313501ND
2018-05-1539311001ND
2018-06-1239750101ND
2018-07-1740177201ND
2018-08-0640553401ND
2018-09-18E19000995004ND
2018-09-1840907401ND
2018-09-27E19001118001ND
2018-10-0941360801ND
2018-11-0541786201ND
2018-12-0542194901ND
2019-01-1542524401ND
2019-02-1342808201ND
2019-03-1343266901ND
2019-04-10435849ND
2019-05-16438936ND
2019-05-21438937ND
2019-06-25443655ND
2019-07-17E20000222010ND
2019-07-18449856ND
2019-08-28455573ND
2019-09-05E20000962001ND
2019-09-0546211001ND
2019-10-02467707010.700 ppb
2019-11-1147048901ND
2019-12-1047529401ND