Transcript Document

Dieterich, M.F., Gieseler, M.E., Short, D.B., and Signorelli, R.T.
Results
Abstract
This device uses electrochemical sensing technology to measure airborne
formaldehyde concentration, as well as ambient temperature and humidity
levels. The formaldehyde concentrations were measured in parts per
million (ppm) ranging from 0 to 10.00 ppm with resolution of 0.01 [3].
Table 1 shows the measurements of CH2O in each room,
ranging from minimum to maximum levels. Figure 2
compares the average concentrations of CH2O for all three
locations.
Formaldehyde , a group 1 carcinogen is a component of indoor air and
may be used to assess overall indoor air quality. Measurements of
formaldehyde were taken with a portable meter at various sites and
compared. Levels ranging from 0.01 ppm to 0.18 ppm formaldehyde were
recorded.
The Formaldemeter 400 uses a sampling frequency of 1 to 3 minutes, and
analyzes the samples within 60 seconds. After each sample was collected, the
device was turned off for a duration of 3-5 minutes to allow the detector to
recover in between measurements (as specified by manufacturer’s manual).
The device operates with a precision of 10%.
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Introduction
The toxic effects of formaldehyde exposure can be classified as follows:
irritation of mucous membrane, contact dermatitis, teratogenicity, and
carcinogenicity [1]. Irritating effects of CH2O exposure such as chest pain
and coughing begin at 0.4 ppm. There are currently no national standards
for indoor exposure in residential homes and businesses. The California
Air Resources Board (CARB) has highly recommends that residential
levels of CH2O remain well below 0.02 ppm. and the American Society for
Heating, Refrigeration and Air Conditioning Engineers (ASHRAE)
recommend a level not to exceed 0.1 ppm.
In homes and offices, a major contributing source of CH2O is cleaning
products. CH2O is found in cleaning products as a biocide, or is formed as
a reaction product when Volatile Organic Compounds (VOCs) react with
ozone in the surrounding atmosphere [2]. This study measures
formaldehyde in various buildings and compares the results to other
studies.
Field Sampling
Indoor measurements of CH2O were collected in various locations at
Robert Morris University, including an anatomy lab, and at one offcampus household. The sampling device used was a Formaldemeter
htV by ENMET Corporation.
Method
A commercially available data logging electrochemical CH2O detector
called the Formaldemeter 400 was employed to evaluate the domestic
levels of formaldehyde indoors.
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CH2O Concentrations (ppm)
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Discussion
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Indoor air samples were collected at various buildings on RMU campus, at
an off-campus home, and in the laboratory after a cat was dissected. The
greatest number of samples was measured at the off-campus house and
CH2O concentrations ranged from 0.01 to 0.18 ppm (see Table 1), with an
average level of 0.64 ppm. The mean measurement recorded at the campus
buildings was 0.02 ppm, and the mean measurement recorded after the cat
was dissected in the laboratory was 0.74. The background level of CH2O
for all sample sites ranged from 0.01-0.02 ppm. At the off-campus house,
the levels of CH2O spiked after cleaning products were used. Our average
CH2O level would have been approximately 0.04 ppm if not affected by
the cleaning products. This average is comparable to a similar study that
found a mean measurement 0.02 ppm CH2O in 179 homes [4].
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0.08
0.06
0.04
0.02
0
Kitchen
living room
fireplae
basement
Sampling Sites
bedroom #1
bedroom #2
Closet
Table 1: Highest levels of CH2O are indicated by the triangle
symbols and lowest levels are indicated by the square symbol.
This increase in CH2O levels may be due to either (i) presence of biocide,
(ii) oxidation of VOCs, or (iii) a possible interference from phenols,
alcohols, or aldehydes with the monitor [5]. If this study were conducted
in the future, the chemicals in the cleaning products would have to be
researched to determine if interfering agents are present.
Cat
Locations
Formaldehyde (CH2O) is a group 1 carcinogen and is categorized in the
same group as benzene, arsenic, asbestos, and ionizing radiation. CH2O is
a pungent, colorless, possible carcinogenic gas that occurs naturally and
from man-made sources. Man-made sources of CH2O include adhesives,
paint, plastics, textiles, pressed wood products (particle board, plywood
panels), and fertilizers. It is also formed during the burning of organic
materials and is found in tobacco smoke [1].
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References
House
[1] Hess-Kosa, K. (2002) Indoor Air Quality. Lewis Publishers, April 2012.
[2] Hahn, S. ,Schneider, K., Gartiser, S., Heger, W., and Mangelsdorf, I. (2010) Consumer exposure to
RMU
biocides-identification of relevant sources and evaluation of possible health effects. Environmental
Health: A Global Access Science Source, Vol. 9, No. 1 Article number 7.
[3] ENMET Formaldemeter htV: http://www.enmet.com/pdf/Formalda_htVManual.pdf, April 2012.
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CH2O Concentration (ppm)
Figure 1: Mean concentration of CH2O at each location
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[4] Sekine, Y.,Fukuda, M.,Takao, Y., ,Ozano, T.,Sakuramoto, H., and Wang, K.W. (2011) Simultaneous
removal of formaldehyde and benzene in indoor air with a combination of sorption-and decomposition-type
air filters. Environmental Technology, Volume 32, Issue 16, 1, pp. 1983-1989, April 2012.
[5] NIOSH Formaldehyde Short Term Study:
http://www.cdc.gov/nceh/ehhe/trailerstudy/pdfs/Formaldehyde%20Instrument%20Report_331-05b.pdf, April
2012.