I have been working in an older house for 3 years. The building
has five bathrooms which, to my knowledge, are not ventilated. A zoning inspector has
advised me that it has high methane levels and that I should leave the windows open when I
am in the building. Odors in the house have become stronger in the past several months,
which are apparently due to septic problems. I have had several sinus problems, as well as
dizzy spells and moodiness as a result of working in the building. Can these
symptoms/health problems be due to exposures to methane? --Kathy, New York Methane
is a common constituent of sewer gas as well as natural gas used for cooking and heating.
It can be detected accurately in a building using a flame ionization detector, an
instrument that costs approximately $6,000. Most zoning inspectors do not have the
capability of measuring methane accurately. As a consequence, I would be somewhat
skeptical of the information provided to you on methane levels in the house.
Methane is the dominant constituent of sewer gas. It is
odorless. Gases such as ammonia and hydrogen sulfide give sewer gas its characteristic
odor. A methane/sewer gas problem should smell like sewer gas. The ammonia in sewer gas
can be highly irritating to the eyes, nose, throat and sinuses.
Given the fact that the house has 5 bathrooms, it is
possible that a sink or even a toilet stool (that hasn't been used for a long time) has a
dry trap. This provides an avenue for sewer gas entry into the house. To remedy this
problem, make sure that sink taps are run periodically and toilets flushed (once every 2-3
weeks). Alternatively sinks or toilets no longer in use should have drain lines capped.
If methane were to be coming from heating/cooking sources,
it will have the characteristic odor of "skunk oil", a sulfur compound added to
natural gas that makes it detectable (in case of a leak).
Sinus problems, dizzy spells, and moodiness- type symptoms
are not consistent with exposure to methane. Sinus problems are commonly associated with
exposures to irritant gases or allergenic substances. In the latter case these include the
spores of a variety of molds, dust mite waste products, and pet allergens. Without knowing
anything about the house's history, it is difficult to ascertain which of these allergens
may pose an exposure risk to you. You may wish to have your sensitivity evaluated by a
Board-certified allergist. Results of such tests may provide valuable clues as to what
allergens may be of concern.
Individuals with allergic reactions or irritant substances
(e.g. formaldehyde or possibly ammonia) tend to develop sinus problems that may affect the
inner ears where our organ of balance is located. This may result in equilibrium problems
experienced as dizzy spells.
Older houses tend to be at higher risk for mold
infestation. Does the house or any of its rooms have a musty smell?
Lastly, though sewer gas is characterized by its
constituent gas-phase substances there is a good probability (though to my knowledge it
has never been studied) that sewer gases can be a source of airborne mold and bacteria
exposures. Sewage contains large quantities of bacteria (responsible for producing sewer
gases). Sewage also contains fungi that are involved in decomposing human waste. The
nature and significance of such potential exposures is however unknown.
March 16, 2000 |
