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H. S. Weinberg
a man-made compound that is commonly found in groundwater contaminated by
leaking underground gasoline-storage tanks (Squillace et al. 1996). The
compound, which imparts a sweet-turpentine odor to water, is a gasoline additive
that reduces air pollution from internal combustion engines. Its average odor
threshold in water has been estimated by one study at parts per billion (ppb)
(Stocking and Kavanaugh 1998). Unfortunately, traditional treatments such as
chlorination will not oxidize MtBE, and more expensive treatment processes such
as air stripping, carbon adsorption, and advanced oxidation are required for its
removal. As such, MtBE has proven to be a fairly widespread and difficult tasteand-odor concern in the United States that has prompted the USEPA to ban its use
as a gasoline additive. Spill sites will gradually be cleaned up but the MtBE
"episode" has had a profound impact on the way the drinking water industry is
planning its future. As more synthetic chemicals make their way into our lives,
many of these compounds will end up in our water supplies, posing a variety of
health-related challenges which will have to be addressed by new technologies.
This chapter presents a snapshot of what is becoming available and demonstrates
where some successes have been achieved.
2 Regulation
The regulation of municipally supplied drinking water is struggling to keep up
with the growing body of toxicological evidence regarding the potential health
effects of chemical byproducts of oxidation and chlorination reactions resulting
from drinking water treatment. The practice of disinfection, for example, has
helped to ensure the nation's safe supply of drinking water against microbiological
infection and caused a dramatic worldwide downturn in the incidence of waterborne disease. This is often highlighted by the occasional breakdown in this safety
net, when drinking water treatment is incorrectly or inadequately practiced, but for
the most part, the incidences of serious illness resulting from poor drinking water
has dropped to a negligible number in the developed world. It was not until the
mid 1970s, however, that countereffects of some drinking water processes were
discovered. It was at around this time that sensitive chemical detection and
separation techniques were becoming routinely available and provided the tools
for water-quality chemists to investigate the chemical quality of drinking water.
Chlorination, by far the most widely practiced disinfection technique then and
now, was quickly discovered to be the source of halogenated volatile bypro ducts
in consumers' waters, which were subsequently determined to have long-term
health implications. The technology was not about to be abandoned in favor of
returning to microbiologically unsafe water, but this was the turning point in terms
of the development of alternative technologies and an acute awareness for the
impact of those technologies on water quality. In the years that followed, a whole
slew of chlorination byproducts were identified, especially in surface waters that
were exposed to natural decaying organic material, and which were quickly
H. S. Weinberg
a man-made compound that is commonly found in groundwater contaminated by
leaking underground gasoline-storage tanks (Squillace et al. 1996). The
compound, which imparts a sweet-turpentine odor to water, is a gasoline additive
that reduces air pollution from internal combustion engines. Its average odor
threshold in water has been estimated by one study at parts per billion (ppb)
(Stocking and Kavanaugh 1998). Unfortunately, traditional treatments such as
chlorination will not oxidize MtBE, and more expensive treatment processes such
as air stripping, carbon adsorption, and advanced oxidation are required for its
removal. As such, MtBE has proven to be a fairly widespread and difficult tasteand-odor concern in the United States that has prompted the USEPA to ban its use
as a gasoline additive. Spill sites will gradually be cleaned up but the MtBE
"episode" has had a profound impact on the way the drinking water industry is
planning its future. As more synthetic chemicals make their way into our lives,
many of these compounds will end up in our water supplies, posing a variety of
health-related challenges which will have to be addressed by new technologies.
This chapter presents a snapshot of what is becoming available and demonstrates
where some successes have been achieved.
2 Regulation
The regulation of municipally supplied drinking water is struggling to keep up
with the growing body of toxicological evidence regarding the potential health
effects of chemical byproducts of oxidation and chlorination reactions resulting
from drinking water treatment. The practice of disinfection, for example, has
helped to ensure the nation's safe supply of drinking water against microbiological
infection and caused a dramatic worldwide downturn in the incidence of waterborne disease. This is often highlighted by the occasional breakdown in this safety
net, when drinking water treatment is incorrectly or inadequately practiced, but for
the most part, the incidences of serious illness resulting from poor drinking water
has dropped to a negligible number in the developed world. It was not until the
mid 1970s, however, that countereffects of some drinking water processes were
discovered. It was at around this time that sensitive chemical detection and
separation techniques were becoming routinely available and provided the tools
for water-quality chemists to investigate the chemical quality of drinking water.
Chlorination, by far the most widely practiced disinfection technique then and
now, was quickly discovered to be the source of halogenated volatile bypro ducts
in consumers' waters, which were subsequently determined to have long-term
health implications. The technology was not about to be abandoned in favor of
returning to microbiologically unsafe water, but this was the turning point in terms
of the development of alternative technologies and an acute awareness for the
impact of those technologies on water quality. In the years that followed, a whole
slew of chlorination byproducts were identified, especially in surface waters that
were exposed to natural decaying organic material, and which were quickly