Wr. Hartley et al., Health risk assessment of groundwater contaminated with methyl tertiary butyl ether (MTBE), WATER SCI T, 39(10-11), 1999, pp. 305-310
Methyl tertiary butyl ether (MTBE), a volatile oxygenate commonly used in f
uels, is a frequent contaminant of some shallow groundwater. Based on limit
ed reporting, concentrations of MTBE in drinking water were generally less
than 10 mu g/L but excursions up to 770 mu g/L have been reported. Based on
current MTBE toxicological data with emphasis on carcinogenic potential, a
nd reproductive and developmental effects, a maximum drinking water level o
f 100 mu g MTBE/L is suggested. This recommended advisory level takes into
consideration the equivocal evidence of the carcinogenicity of MTBE in huma
ns and low potency in an oral exposure animal study. Definitive conclusions
regarding health risks to the general population from MTBE contamination o
f drinking water are not possible due to a paucity of monitoring data. Ther
e is increased evidence of contamination of storm water and shallow groundw
ater from primarily, nonpoint sources. Considering MTBE mobility and stabil
ity in water, movement to deep groundwater and drinking water supplies seem
s probable. In light of projected increased MTBE use, there is a need for a
more rigorous monitoring program to define the frequency of MTBE contamina
tion of drinking water supplies and to develop risk management policies. (C
) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved.