SICK BUILDINGS
Left untreated/exposures not corrected, sick building symptoms become
chronic.
Researchers trace a rise in indoor air pollution to the 1970’s when the energy crisis led to a cut in
air handling rates. In 1973, the American Society of Heating, Refrigerating, and Air-Conditioning
Engineers (ASHRAE) reduced the professional standard for the minimum amount of outdoor air
brought into buildings by 70%. In the past, office employees had received 20-30 cubic feet of
outdoor air per minute person (cfm/p). The 1973 recommendation called for heating, ventilation,
and air-conditioning (HVAC) systems to provide a minimum of just 5 cfm/p of outdoor air.i
Sick building syndrome has been attributed to a variety of conditions, including inadequate
ventilation, pollutants such as volatile organic compounds, moisture conditions related to
humidification and cooling systems, biological contamination, indoor chemical use, and outdoor
contaminants brought in through the ventilation system.ii,iii,iv,v,vi Important indoor air pollutants
include tobacco smoke, volatile organic compounds, formaldehyde, combustion products,
microorganisms and aeroallergens (eg. mold).2 New buildings can have pollutant volatile organic
compound levels up to 100 times that of outdoor levels. New buildings, building remodeling and
new materials used in buildings, including paints, adhesives, vinyl and hard rubber moldings,
carpet and particle board emit chemicals in large quantities for a number of months.2,vii
Many documented cases of sick building syndrome have been reported in newly constructed or
newly remodeled energy-efficient buildings having a centrally controlled mechanical ventilation
system, typically sealed air conditioned buildings that do not allow windows to be opened.2,viii
Under these conditions a wide variety of pollutants can contaminate the indoor air.2,6,8,ix Poorly
designed or inadequately functioning ventilation systems also allow buildup of pollutants from
room deodorizers, aerosol sprays, recently dry cleaned clothes, plastics, fabric softeners,
pesticides, cosmetics, cleaning agents, etc., creating exposures in addition to building new
construction and remodeling materials.2 Reduced air exchange rates in existing and newly
constructed or remodeled buildings markedly increases the problem of indoor air pollution.2,9
Many of these pollutants in these substances are irritants to the respiratory system and/or
neurotoxic (affecting the brain and nervous system).2,x,xi Sensory irritation is a prevalent symptom
in relation to indoor air quality creating trigeminal nerve stimulation producing stinging, irritation,
burning and/or prickling of eyes and mucous membranes of the respiratory system.xii Commonly it
is not an individual chemical but rather the added effects of a “Chemical Mixture”, and the
degree to which health changes are additive (or more than additive) increases with the complexity
of the mixture (more chemicals present) and the fat soluability.12 More chemicals present and
increased fat soluability of the chemicals increases the degree of added effect on health. 12 New
building materials in new buildings and remodeling adds to the number of chemicals present, 2
providing a scientific basis for higher sick building syndrome risk with new building materials.2
Another study found brain abnormalities in individuals who were in sick building situations.xiii
Exposure levels of pollutants in buildings can be significantly reduced by increasing outdoor air
supply,xiv using bakeout procedures for new building materials14 (new buildings and renovations,
remodeling and repair using new materials), by reducing pollutant sources14 (less toxic, lower
off-gasing potential substances), delaying occupancy after new material use and of course by
adequate and proper design and maintenance of the heating, ventilation and air conditioning
(HVAC) system. Usual half life of building pollutants is months; this can be reduced to days by
following bakeout and other control practices.14 Thus, when measurements of building exposure
levels are made months or longer after new material use, this significantly underestimate exposure
persons exposed during or shortly after use.
Short term memory impairment was demonstrated in a double blind inhalantion challenge
exposure study of individuals who had reported difficulty with indoor air quality but no physical
or psychiatric disease when exposed to a mixture of pollutants commonly found in indoor air at
total VOC levels of 5 and 25mg/m,4,xv considered low concentration,14,15 well below occupational
exposure legal standards. SPECT brain scans on adults with chronic symptoms following a history
of “tight” office building exposure to mixed volatile organic compounds (VOCs) compared to
healthy controls showed reduced ability to take up the tracer substance in the early phase of
injection. Increased tracer was found in the late phase of injection, consistent with impaired
detoxification ability and/or reduced brain blood flow. Changes were seen in frontal, temporal
and limbic brain areas.xvi Depending on the severity of a sick building exposure, between 10% to
90% of exposed individuals develop chronic fatigue with other chronic symptoms.xvii
Because of additive and synergistic levels of building pollutants,14 wide variation in individual
,
susceptibility2 15,xviii,xix,xx,xxi,xxii and other factors,14 occupational exposure standards are too high to
protect all members of the population from brain effects.14 Susceptibility to toxic effects from
exposure varies widely, depending on age, gender, inter-current disease, genetic makeup, prior
exposure, and nutritional and physiologic status, causing large differences in response among
individuals to a similar chemical exposure.2,18,19,20,21,22 Individuals who may be at greater risk of
developing sick building syndrome are those who have a tendency to be more reactive.xxiii,xxiv
i
“Sick Days at Work”, Environ Health Perspect, 104 (10), 1032, Oct. 1996.
A.B. Tarcher, Principals and Practice of Environmental Medicine, Plenum Publishing Corp, New York,NY. 1992.
iii
S. Burge et al “Sick building syndrome”: A study of 4373 workers, Ann Occuo Hyg 31:493, 1987.
iv
M.J. Finnegan etal. “The sick building syndrome: Prevalence studies”, Br Med J 289: 1573, 1984.
v
K. Kreiss, “The epidemiology of building-related complaints and illness”’ Occup Med 4:575, 1989.
vi
L. Molhave, “Volatile organic compounds as indoor air pollutants”, Indoor Air and Human Health, Lewis Publishers, Chelsea MI 1985.
vii
L.S. Sheldon etal. “Indoor Air Quality In Public Buildings”, Vol II, U.S. Environmental Protection Agency (EPA 600-6-88-009 Aand B),
Washington DC.,1988.
viii
World Health Organization: Indoor Air Pollutants Exposure and Health Effects Assessment, EURO Reports and Studies 78, WHO, Geneva,
1982.
ix
American Thoracic Society: Environmental Controls and Lung Disease, Amer Rev Respir Dis 142:915, 1990.
x
N.H. Proctor and J.P. Hughes, Editors, Chemical Hazards of the Workplace, J.B. Lippencott, Philadelphia PA.
xi
R.E. Lenga, Editor, The Sigma-Aldrich Library of Chemical Saftey Data, pp.1-3636, Sigma Aldrich Corp., Milwaukee, WI.
xii
A. Hempel-Jorgensen, S.K. Kjaergaard, L. Molhave and K.H. Huchnell (later with Neurotoxicology Division, US EPA), “Sensory eye
irritation in humans exposed to mixtures of volatile organic compounds”, Archiv Environ Health 54: 416-424, 1999.
xiii
D.A. Middaugh, et al., "Sick building syndrome: Medical evaluation of two work forces," J. Occup Med, 34:1197-1203, 1992.
xiv
J.R. Girman, (California Dept. Health Services), “Volatile organic compounds and building bake-out”, Occupational Medicine State of
the Art Reviews 4: 695-712, 1989.
xv
L. Molhave etal., “Human reactions to low concentration of volatile organic compounds”, Environ Int 8: 117-127, 1986.
xvi
C.E. Fincher, et. al., “Comparison of single photon emission computed tomography findings in cases of healthy adults and solvent-exposed
adults”, Am J. Ind Med 31:4-14, 1997.
xvii
Chester, AC and PH Levine, “Concurrent SBS and CFS: Epidemic Neuromyasthenia revisited”, Clin Infect Dis 18 (Suppl 1) S43-S48, 1994.
xviii
Committee on the Epideniology of Air Pollutants, National Research Council (U.S. Govt): Epideniology and Air Pollution, National
Academy Press, Washington DC., 1985.
xix
Committee on Indoor Air Quality: Policies and Procedures for Control of Indoor Air Quality in Existing Buildings, National Academy Press,
Washington DC., 1987.
xx
Committee on Indoor Air pollutants, National Research Council (U.S. Govt), National Academy Press, Washington DC., 1981.
xxi
E.S. Vessel, “Effects of human physiologic and genetic variability on the development and expression of pollutant-related diseases”.
Environmental Impacts on Human Health, Praeger, New York, NY.,1987.
xxii
M.F. Vine and L.T. McFarland, “Markers of Susceptibility”, Biologic Markers in Epidemiology, Oxford University Press, London, 1990.
xxiii
D. Norback, et al., "Volatile organic compounds, respirable dust and personal factors related to prevalence and incidents of sick building
syndrome in primary schools," British J. Indust Med, 47:733-741, 1990.
xxiv
D. Norback, et al., "Indoor air quality and personal factors related to the sick building syndrome," Scand J Work Environ Health,
ii
2
16:121-128, 1990.
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