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Sick Building Syndrome
Sick Building Syndrome
Source: Environmental Illness Resource
What is Sick Building Syndrome?
Sick building syndrome is a broad label that covers a range of symptoms thought to be triggered
when the sufferer spends time in a particular building. Symptoms range from specific symptoms
such as itchy eyes, skin rashes, and nasal allergy symptoms, to more vague symptoms such as
fatigue, aches and pains, and sensitivity to odours.
The term "sick building syndrome", was first coined in the 1970s, and its recognition at this time
may in part be attributable to the increasing presence of electronic equipment and other factors. It
is used when the symptoms of a significant number of people occupying a particular building, are
associated with their presence in that building. In most cases sick building syndrome occurs in
office buildings, although it may also occur in other communal buildings such as schools and
apartment buildings.
According to the US Environmental Protection Agency (EPA), sick building syndrome is strongly
suspected when the following circumstances are present:
•Symptoms are temporally related to time spent in a particular building or part of a building
•Symptoms resolve when the individual is not in the building
•Symptoms recur seasonally (heating, cooling)
•Co-workers, peers have noted similar complaints
The circumstances most suggestive of sick building syndrome are presence of common symptoms
amongst a group of building occupants that are present when they are in the building and absent
when they are not in the building.
The EPA highlights the distinction between sick building syndrome and building related illness. The
latter term is used for situations in which signs and symptoms of diagnosable illness are readily
identified and can be attributed directly to specific airborne building contaminants. Examples of
building related illnesses are Legionnaires' Disease and hypersensitivity pneumonitis. In contrast,
the cause(s) of symptoms in cases of sick building syndrome are often hard to pin down and in
many cases a range of factors may contribute to the situation. When a sick building is identified an
extensive investigation by people such as the employer, building owner or manager, building
investigation specialist, and if necessary, local medical authority epidemiologists and other public
health officials, is often required.
Once a sick building has been investigated various measures must be taken to ensure the cause
(s) are removed to make it safe for the occupants.
Although the problem of sick building syndrome has been recognized for decades, statistics
regarding the prevalence of the problem are limited. A World Health Organization (WHO) report
from 1984 suggested that up to 30% of new and renovated buildings worldwide may generate
excessive complaints related to indoor air quality (1). This high rate may be associated with modern
mass produced construction materials that tend to offgas irritating volatile organic chemicals
(VOCs). In a US report, of office workers questioned at random, 24% reported air quality problems
in their work place, and 20% believed this harmed their ability to do their job effectively (2).
Symptoms of Sick Building Syndrome
Sick building syndrome involves a variety of seemingly unrelated symptoms, much like other
unexplained conditions such as chronic fatigue syndrome (CFS), and Gulf War syndrome (GWS)
do. Some authorities have attempted to separate the symptoms into distinct categories such as
'allergic' and 'non-allergic', or 'chemical related' and 'microbe related'. Since there is yet no
concensus on these distinctions, the common symptoms of SBS are listed here together:
•Headache
•Eye, nose, and throat irritation
•Dry cough
•Dry, itchy skin, rashes
•Dizziness and nausea
•Difficulty in concentrating
•Fatigue
•Sensitivity to odours
Sensitivity to odours is the definitive symptom of the related condition multiple chemical sensitivity
(MCS). Both SBS and MCS are thought, at least in part, to be due to exposure to VOC's in the air.
Causes of Sick Building Syndrome
Although in many cases the exact mechanism by which a building, or substances within the
building, are causing the occupants to become ill is unknown, the problem areas can usually be
identified and remedial action taken.
In many SBS cases poor building design, maintenance, and/or operation of the structure's
ventilation system may be at fault (3). The ventilation system in particular is often found to be at the
heart of the problem, and can itself be a source of irritants. In addition, a poor ventilation system
can result in a buildup of pollutants within the building, in which case the indoor environment can
often have air quality much lower than the outdoor air, even in a heavily polluted city centre with it's
clouds of vehicle exhaust and other pollutants. Interior design factors, such as the arrangement of
individual offices and cubicles, may also interfere with efficient functioning of ventilation systems.
Essentially poor office design and maintenance of the ventilation system can amplify the negative
health effects of various factors, both biological and chemicals, that we'll discuss below.
It has also been suggested that very low levels of specific pollutants, such as VOCs, that are
present inside a building may act synergistically, or at least in combination, to cause symptoms of
illness. The chemical industry is not strictly regulated, with the majority of the many thousands of
chemicals in everyday use having not been tested for health effects before their introduction.
Chemicals have traditionally been thought to be toxic only above certain concentrations but
scientists are now finding they often have health damaging effects at much lower levels, previously
considered to be safe. In the case of small amounts of multiple different chemicals acting in
combination to cause illness, there is virtually no research on this to refer to, so any effects are
entirely unknown.
The symptoms of SBS are likely the result of a combination of factors. Many of the symptoms can
be attributed either to the known toxic effects of high levels of certain chemicals. Other symptoms
are typical of allergic reactions which could be triggered by various allergens in a building. Still
other symptoms are very reminiscent of those experienced by sufferers of multiple chemical
sensitivity and many of the indoor pollutants identified in sick buildings are also those said to cause
symptoms in those suffering from MCS. It's likely that all of these mechanisms and associated
pollutants are involved in SBS.
The following is a closer look at the various indoor pollutants that can contribute to making a
building 'sick':
Chemical Pollutants
Combustion Pollutants
Various chemical pollutants that can affect the health of a building's occupants are produced when
heating systems or gas fired appliances such as stoves are poorly maintained, and thus don't burn
fuel efficiently, or don't vent exhaust correctly.
The main pollutants from this source are:
Carbon Monoxide (CO) - a gaseous asphyxiant, CO is known as the 'silent killer' as it is
colourless and odourless. When it is breathed in CO binds to red blood cells preventing them from
carrying oxygen and essentially suffocating the victim. Methylene Chloride may also breakdown to
form Carbon Monoxide as well. Methylene Chloride is a common toxic solvent used in many
products such as paint and paint strippers.
Sulphur Dioxide (SO2) - is a colourless gas with a strong odour like that of a struck match.
Sulphur dioxide is an irritant to the respiratory system and exposure to high concentrations for
short periods of time can constrict the blood vessels in the lungs and increase mucous flow, making
breathing difficult. Those most at risk from these effects include children, the elderly, those with
chronic lung disease, and asthmatics. Other harmful effects of SO2 include it's ability to impair the
respiratory system's defenses against foreign particles and bacteria when chronically exposed to
low concentrations, and enhance the harmful effects of ozone.
Nitrogen Dioxide (NO2) - is another toxic gas produced from combustion of fuels. It can be fatal
in high concentrations, whilst lower levels, like SO2, act as irritants to lung tissue. Long term low
level exposure can destroy lung tissue and lead to emphysema. Long term exposure also makes
people more susceptible to respiratory infections such as pneumonia and influenza. The risk of ill-
effect is greatest for the same groups most affected by SO2.
Volatile Organic Compounds (VOCs)
Volatile organic compounds are organic (carbon-based) compounds that evaporate at ambient
temperatures within a building. VOCs can 'offgas' from building materials and much of the contents
of most buildings. These compounds often have effects on health from irritating the eyes, nose,
and throat, to causing breathing difficulties, to increasing the risk of developing cancer. An example
of a VOC commonly present in indoor air is formaldehyde, which is also one of the most toxic being
both a strong respiratory irritant, and carcinogen.
Building Construction - High levels of formaldehyde offgas from particle board. Modern buildings or
buildings renovated with modern materials suffer the most from offgassing of VOCs due to the
extensive use of particle board rather than solid wood or stone/brick for interior walls etc. Particle
board is also often used in place of solid wood in modern furniture such as computer desks and
shelving. Although a cheap alternative to other materials, particle board is a major source of VOCs
due to the high content of powerful adhesives used in its manufacture. Formaldehyde and other
VOCs offgas from particle board used in building construction and furniture for years, with the
highest concentrations being generated in the first 6 months.
Carpeting is another major source of VOCs in many buildings since a large number of chemicals
are used in their manufacture in the form of glues, backing materials, flame retardants, and dyes.
The specific VOCs that offgas from new carpet include acetone, toluene, xylene, formaldehyde,
and benzene derivatives. These chemicals are all known to cause irritation, effect breathing, and
produce various neurological symptoms. Many of them are also potent carcinogens.
Finishes such as paints and varnishes can also increase the VOC content of a building or
room. That fresh paint smell is the result of paints high content of VOCs in the form of solvents and
binders. In the case of oil based paints, whose use if thankfully being reduced in indoor paints, the
entire base of the paint is made up of VOCs. The US EPA has determined that the off-gassing from
architectural coatings is estimated to account for about 9% of the VOC emissions from all consumer
and commercial products. Many of the VOCs used in paints have ben banned or are being phased
out as they are now recognized to be highly toxic and/or carcinogenic.
Chemicals Used Within A Building -
The various chemical based products routinely used inside a building can be an equally large
source of VOCs. Products that contain VOCs range from chemical products used to clean a
building to marker pens and printer ink, common in an office or school environment.
Cleaning products contain a range of toxic VOCs including diethyl phthalate, found in a range of
products, toluene, found in stain removers, and hexane/xylene, found in aerosol sprays. Diethyl
Phthalate is a known endocrine disrupter (interferes with hormone activity), toluene is a known
carcinogen (cancer causing agent) and can cause neurological problems, and finally both hexane
and xylene can also damage the nervous system.
Marker pens are a particularly concentrated source of VOCs as their very strong smell indicates.
Their chemical constituents include methyl ethyl ketone (MEK), toluene, and formaldehyde. The
VOCs present in marker pens have various consequences for human health including neurological
effects. Ink cartridges and toners used in printers also contain VOCs, albeit at less concentrated
levels than marker pens.
Electronic equipment also offgases a large amount of VOCs. In an office full of computers, these
essential pieces of equipment can be a substantial source of VOCs which offgas from materials
such as flame retardants and various other chemicals used in their manufacture.
Besides the above there are many other sources of VOCs within the average office building or
other communal building. These include air fresheners, personal care products such as
deodorants and perfumes, and laundry detergent and fabric softener residues on the occupants
clothing.
For a more detailed look at some of these VOC sources see our multiple chemical sensitivity (MCS)
page.
Heavy metals
Although much has been done to reduce or eliminate the use of heavy metals in buildings in over
the past few decades, older buildings may still contain a significant amount of these highly toxic
substances. Buildings built or extensively renovated after the early 90's in most developed
countries are not likely to have a problem, but many buildings constructed before this time could
pose a risk for heavy metal poisoning. The two most common heavy metals present in buildings are
lead and mercury.
Indoor paint manufactured before 1990 and outdoor latex paint manufactured before 1991 may
contain mercury, which was added to paint mainly to prevent build up of mold on walls, as mercury
is an effective antifungal agent. Mercury can damage health in a number of ways, from impairing
detoxification to causing serious neurological damage and birth defects. In fact, the mercury
containing compound thimerosal was routinely added to vaccines to prevent contamination by fungi
and bacteria until concern about its role in causing autism recently lead to its removal. Mercury may
also be present in small amounts in computer and electronic equipment.
Lead is another common problem in older buildings because it was also added to paints until a
couple of decades ago. Lead-based paint is still a major problem in older buildings particularly
when the residues are disturbed and become airborne such as during renovation or construction
projects. Like mercury, lead can cause severe neurological damage and a host of other problems.
Unless disturbed by renovation it's unlikely that heavy metals would be a major contributor to cases
of sick building syndrome. For older buildings the risk is there however so must always be
considered.
Biological Pollutants
As well as the chemical pollutants described above, various biological contaminants often
contribute to cases of sick building syndrome. In fact biological factors are reported to be behind
the majority of cases. These biological pollutants can cause illness through three different
mechanisms:
•Infection
•Allergy/Hypersensitivity
•Toxicosis - symptoms caused by toxins produced by micro-organisms e.g. mycotoxins produced by
mold/fungi
There are many sources of biological pollution that can affect a building and many reasons why a
building might become contaminated and cause illness in its occupants. The following are the main
sources of this form of pollution:
Toxic Black Mold - is reported to be the leading cause of sick building syndrome and building
related illness. Mold grows rapidly in warm and damp environments. If the indoor environment is too
humid or if water damage occurs through leaks or rising damp, mold growth is very likely to occur.
Viruses & Bacteria - are common in every building, especially high occupancy buildings such as
offices and schools. These micro-organisms can make a significant contribution to causing SBS.
They become increasingly problematic if humidity levels are either too low or too high, as a result of
how their growth is affected and the fact that our defenses against them are also affected by
humidity levels.
Dust Mites - are highly allergenic and thrive on the constant supply of shed human skin cells that
accumulate in carpeting, soft furnishings, and other areas. Like mold and bacteria, dust mites like
the warm and relatively humid environment that we usually provide in our buildings.
Pollen - is another allergy causing substance that can accumulate in a building if proper ventilation
and filtering is not maintained. Pollens from various trees and plants can be troublesome for a
great number of people. Aside from being carried on breezes through open doors or windows,
pollens can also be brought indoors on the occupants shoes and clothing.
Insect Body Parts - although not well known are especially potent allergens for some people.
Cockroach allergens are particularly troublesome allergens and are commonly implicated as
contributors to sick building syndrome. Usually become a problem only when sanitation is poor.
The above are collectively known as bioaerosols. The common definition of a bioaerosol is any
extremely small living organism or fragment of living things suspended in the air. They cannot be
seen without a magnifying glass or microscope. Of course when a large growth of mold occurs, it
does then become visible to the naked eye.
Reasons For a Building Becoming Contaminated by Bioaerosols
Moisture
The primary reason why bioaerosols become a major problem in buildings is the presence of damp
in the buildings structure and/or a high level of humidity in the air. There are numerous reasons
why such a situation could arise, some of the most common being:
•Water damage to homes from flooding or storm damage.
•Leaks in plumbing, roofs, or from air conditioners or HVAC systems.
•Condensation on central air pipes, HVAC components, or other cool surfaces where insulation
may not be present, is insufficient, or has become damaged. Uninsulated air conditioning coils or
pipes will "sweat" the most when hot humid air contacts them such as during warm months.
•Ice damming on building roofs which allows water to seep under shingles and through roof
sheathing.
•Dehumidifiers and humidifiers.
•Pets
•Moisture from unvented or poorly vented kitchens and bathrooms.
•Poor insulation causing drafts or the "chimney effect".
•Defective heating and air systems such as clogged condensation drain lines and full drip pans.
Hygiene and Cleaning
Poor sanitary and cleaning practices also contribute to a building becoming contaminated with
bioaerosols. In a high occupancy building for example, germs from bathrooms can easily be spread
to the rest of the building if they are not cleaned and disinfected both effectively and regularly.
People not washing their hands after using the bathroom can also be a big problem.
Another problem is often inadequate or poorly maintained cleaning equipment. A poorly functioning
vacuum cleaner for example can do more harm than good by spreading dust around rather than
picking it up. As we have heard, dust is a breeding ground for micro-organisms like dust mites that
cause allergies in many people. It may also contain other allergens such as pollens that have either
blown into the building or been carried in by the occupants. Dust may also harbour disease causing
bacteria and other unpleasant organisms. Efficient vacuum cleaners are thus essential pieces of
equipment for avoiding a sick building. Models equipped with HEPA filters which remove even the
tinniest particles are infinitely preferable.
Going back to chemical pollutants, growing research shows that chemicals, such as flame
retardants that are commonly used in electrical equipment and on furniture, accumulate in dust. If a
building is not kept free from dust by regular and effective cleaning, the amounts of chemicals
present will only increase and pose an ever greater risk for the occupants health.
Other Factors That May Contribute to Sick Building Syndrome
Besides the more obvious chemical and biological pollutants that are commonly present in buildings
and can lead to SBS, there are a number of more subtle factors that can also contribute,
sometimes significantly. The most common of these are:
Fluorescent Lighting and Electrical Equipment - People commonly report feeling unwell after
spending time in buildings lit entirely with fluorescent strip lighting. The flickering light is very harsh
and tends to give even otherwise healthy people headaches and make them feel drained. Many
people also complain of feeling unwell when they spend time close to computer screens and other
electrical equipment. It has been suggested that high frequency electromagnetic fields (EMFs)
which are generated by electrical equipment and a building's wiring can cause a host of unpleasant
symptoms such as fatigue, headaches, and inability to concentrate. Electrical Hypersensitivity
(EHS) is the term used to describe the condition in which people are made ill by electromagnetic
radiation.
Temperature - Although many would dismiss the ambient temperature within a building as a minor
consideration, an environment that is either too hot or too cold can have a major effect on how
people feel. With extremes of temperature the body has to work hard to maintain its own internal
temperature at the right level. With resources focused on this task people can quickly become tired
and drained and experience a wide range of symptoms. If the temperature is too hot for prolonged
periods for example, people can become dehydrated with potentially serious consequences for
their health.
Humidity - again can put a strain on the body as it tries to maintain equilibrium. Like high
temperature, a very humid environment can lead to dehydration and associated problems.
Noise - is an equally important factor. Too much noise can be draining and produce headaches
and other symptoms. It also makes it hard to concentrate so impacts on the productivity of workers
in an office for example.
Bad Office Design/Ergonomics - A badly designed workplace can cause numerous health
problems. A cramped office with uncomfortable furniture can result in injuries such as those to the
back as well as injuries such as repetitive strain injury (RSI) from repetitive tasks such as typing.
Stress - is another important consideration in an office building in particular. Stress can be caused
by work pressures such as deadlines but also by all of the other factors we've discussed here that
often relate to a building's design. Stress is a leading cause of absenteeism as it can result not only
in psychological distress but also many physical ailments as well.
What Can be Done About Sick Building Syndrome?
If you and other people living or working in the same building experience health problems that seem
to only be present when you are in that building, or at least get much worse, then it is reasonable to
suspect sick building syndrome. You should report the situation to the landlord, office manger, or
whomever is responsible for the building and ask them to have an inspection carried out. If they are
unwilling to cooperate then you may have to get local authorities such as an environmental health
agency involved.
After a thorough environmental health inspection is carried out on a building to determine possible
causes for the occupants health complaints, there are many measures that can be taken to rectify
the situation. A combination of some of the factors we've discussed above will usually be involved
and all will have to be tackled. Measures taken may include an overhaul or replacement of the
ventilation system, structural repairs to prevent leaks and damp, a review of chemicals used in the
building, a review of cleaning practices, and professional mold removal.
The important thing is to take action to have a suspected sick building investigated as soon as
possible as it is likely that the problem will only get worse if not addressed.
Source: Environmental Illness Resource
What is Sick Building Syndrome?
Sick building syndrome is a broad label that covers a range of symptoms thought to be triggered
when the sufferer spends time in a particular building. Symptoms range from specific symptoms
such as itchy eyes, skin rashes, and nasal allergy symptoms, to more vague symptoms such as
fatigue, aches and pains, and sensitivity to odours.
The term "sick building syndrome", was first coined in the 1970s, and its recognition at this time
may in part be attributable to the increasing presence of electronic equipment and other factors. It
is used when the symptoms of a significant number of people occupying a particular building, are
associated with their presence in that building. In most cases sick building syndrome occurs in
office buildings, although it may also occur in other communal buildings such as schools and
apartment buildings.
According to the US Environmental Protection Agency (EPA), sick building syndrome is strongly
suspected when the following circumstances are present:
•Symptoms are temporally related to time spent in a particular building or part of a building
•Symptoms resolve when the individual is not in the building
•Symptoms recur seasonally (heating, cooling)
•Co-workers, peers have noted similar complaints
The circumstances most suggestive of sick building syndrome are presence of common symptoms
amongst a group of building occupants that are present when they are in the building and absent
when they are not in the building.
The EPA highlights the distinction between sick building syndrome and building related illness. The
latter term is used for situations in which signs and symptoms of diagnosable illness are readily
identified and can be attributed directly to specific airborne building contaminants. Examples of
building related illnesses are Legionnaires' Disease and hypersensitivity pneumonitis. In contrast,
the cause(s) of symptoms in cases of sick building syndrome are often hard to pin down and in
many cases a range of factors may contribute to the situation. When a sick building is identified an
extensive investigation by people such as the employer, building owner or manager, building
investigation specialist, and if necessary, local medical authority epidemiologists and other public
health officials, is often required.
Once a sick building has been investigated various measures must be taken to ensure the cause
(s) are removed to make it safe for the occupants.
Although the problem of sick building syndrome has been recognized for decades, statistics
regarding the prevalence of the problem are limited. A World Health Organization (WHO) report
from 1984 suggested that up to 30% of new and renovated buildings worldwide may generate
excessive complaints related to indoor air quality (1). This high rate may be associated with modern
mass produced construction materials that tend to offgas irritating volatile organic chemicals
(VOCs). In a US report, of office workers questioned at random, 24% reported air quality problems
in their work place, and 20% believed this harmed their ability to do their job effectively (2).
Symptoms of Sick Building Syndrome
Sick building syndrome involves a variety of seemingly unrelated symptoms, much like other
unexplained conditions such as chronic fatigue syndrome (CFS), and Gulf War syndrome (GWS)
do. Some authorities have attempted to separate the symptoms into distinct categories such as
'allergic' and 'non-allergic', or 'chemical related' and 'microbe related'. Since there is yet no
concensus on these distinctions, the common symptoms of SBS are listed here together:
•Headache
•Eye, nose, and throat irritation
•Dry cough
•Dry, itchy skin, rashes
•Dizziness and nausea
•Difficulty in concentrating
•Fatigue
•Sensitivity to odours
Sensitivity to odours is the definitive symptom of the related condition multiple chemical sensitivity
(MCS). Both SBS and MCS are thought, at least in part, to be due to exposure to VOC's in the air.
Causes of Sick Building Syndrome
Although in many cases the exact mechanism by which a building, or substances within the
building, are causing the occupants to become ill is unknown, the problem areas can usually be
identified and remedial action taken.
In many SBS cases poor building design, maintenance, and/or operation of the structure's
ventilation system may be at fault (3). The ventilation system in particular is often found to be at the
heart of the problem, and can itself be a source of irritants. In addition, a poor ventilation system
can result in a buildup of pollutants within the building, in which case the indoor environment can
often have air quality much lower than the outdoor air, even in a heavily polluted city centre with it's
clouds of vehicle exhaust and other pollutants. Interior design factors, such as the arrangement of
individual offices and cubicles, may also interfere with efficient functioning of ventilation systems.
Essentially poor office design and maintenance of the ventilation system can amplify the negative
health effects of various factors, both biological and chemicals, that we'll discuss below.
It has also been suggested that very low levels of specific pollutants, such as VOCs, that are
present inside a building may act synergistically, or at least in combination, to cause symptoms of
illness. The chemical industry is not strictly regulated, with the majority of the many thousands of
chemicals in everyday use having not been tested for health effects before their introduction.
Chemicals have traditionally been thought to be toxic only above certain concentrations but
scientists are now finding they often have health damaging effects at much lower levels, previously
considered to be safe. In the case of small amounts of multiple different chemicals acting in
combination to cause illness, there is virtually no research on this to refer to, so any effects are
entirely unknown.
The symptoms of SBS are likely the result of a combination of factors. Many of the symptoms can
be attributed either to the known toxic effects of high levels of certain chemicals. Other symptoms
are typical of allergic reactions which could be triggered by various allergens in a building. Still
other symptoms are very reminiscent of those experienced by sufferers of multiple chemical
sensitivity and many of the indoor pollutants identified in sick buildings are also those said to cause
symptoms in those suffering from MCS. It's likely that all of these mechanisms and associated
pollutants are involved in SBS.
The following is a closer look at the various indoor pollutants that can contribute to making a
building 'sick':
Chemical Pollutants
Combustion Pollutants
Various chemical pollutants that can affect the health of a building's occupants are produced when
heating systems or gas fired appliances such as stoves are poorly maintained, and thus don't burn
fuel efficiently, or don't vent exhaust correctly.
The main pollutants from this source are:
Carbon Monoxide (CO) - a gaseous asphyxiant, CO is known as the 'silent killer' as it is
colourless and odourless. When it is breathed in CO binds to red blood cells preventing them from
carrying oxygen and essentially suffocating the victim. Methylene Chloride may also breakdown to
form Carbon Monoxide as well. Methylene Chloride is a common toxic solvent used in many
products such as paint and paint strippers.
Sulphur Dioxide (SO2) - is a colourless gas with a strong odour like that of a struck match.
Sulphur dioxide is an irritant to the respiratory system and exposure to high concentrations for
short periods of time can constrict the blood vessels in the lungs and increase mucous flow, making
breathing difficult. Those most at risk from these effects include children, the elderly, those with
chronic lung disease, and asthmatics. Other harmful effects of SO2 include it's ability to impair the
respiratory system's defenses against foreign particles and bacteria when chronically exposed to
low concentrations, and enhance the harmful effects of ozone.
Nitrogen Dioxide (NO2) - is another toxic gas produced from combustion of fuels. It can be fatal
in high concentrations, whilst lower levels, like SO2, act as irritants to lung tissue. Long term low
level exposure can destroy lung tissue and lead to emphysema. Long term exposure also makes
people more susceptible to respiratory infections such as pneumonia and influenza. The risk of ill-
effect is greatest for the same groups most affected by SO2.
Volatile Organic Compounds (VOCs)
Volatile organic compounds are organic (carbon-based) compounds that evaporate at ambient
temperatures within a building. VOCs can 'offgas' from building materials and much of the contents
of most buildings. These compounds often have effects on health from irritating the eyes, nose,
and throat, to causing breathing difficulties, to increasing the risk of developing cancer. An example
of a VOC commonly present in indoor air is formaldehyde, which is also one of the most toxic being
both a strong respiratory irritant, and carcinogen.
Building Construction - High levels of formaldehyde offgas from particle board. Modern buildings or
buildings renovated with modern materials suffer the most from offgassing of VOCs due to the
extensive use of particle board rather than solid wood or stone/brick for interior walls etc. Particle
board is also often used in place of solid wood in modern furniture such as computer desks and
shelving. Although a cheap alternative to other materials, particle board is a major source of VOCs
due to the high content of powerful adhesives used in its manufacture. Formaldehyde and other
VOCs offgas from particle board used in building construction and furniture for years, with the
highest concentrations being generated in the first 6 months.
Carpeting is another major source of VOCs in many buildings since a large number of chemicals
are used in their manufacture in the form of glues, backing materials, flame retardants, and dyes.
The specific VOCs that offgas from new carpet include acetone, toluene, xylene, formaldehyde,
and benzene derivatives. These chemicals are all known to cause irritation, effect breathing, and
produce various neurological symptoms. Many of them are also potent carcinogens.
Finishes such as paints and varnishes can also increase the VOC content of a building or
room. That fresh paint smell is the result of paints high content of VOCs in the form of solvents and
binders. In the case of oil based paints, whose use if thankfully being reduced in indoor paints, the
entire base of the paint is made up of VOCs. The US EPA has determined that the off-gassing from
architectural coatings is estimated to account for about 9% of the VOC emissions from all consumer
and commercial products. Many of the VOCs used in paints have ben banned or are being phased
out as they are now recognized to be highly toxic and/or carcinogenic.
Chemicals Used Within A Building -
The various chemical based products routinely used inside a building can be an equally large
source of VOCs. Products that contain VOCs range from chemical products used to clean a
building to marker pens and printer ink, common in an office or school environment.
Cleaning products contain a range of toxic VOCs including diethyl phthalate, found in a range of
products, toluene, found in stain removers, and hexane/xylene, found in aerosol sprays. Diethyl
Phthalate is a known endocrine disrupter (interferes with hormone activity), toluene is a known
carcinogen (cancer causing agent) and can cause neurological problems, and finally both hexane
and xylene can also damage the nervous system.
Marker pens are a particularly concentrated source of VOCs as their very strong smell indicates.
Their chemical constituents include methyl ethyl ketone (MEK), toluene, and formaldehyde. The
VOCs present in marker pens have various consequences for human health including neurological
effects. Ink cartridges and toners used in printers also contain VOCs, albeit at less concentrated
levels than marker pens.
Electronic equipment also offgases a large amount of VOCs. In an office full of computers, these
essential pieces of equipment can be a substantial source of VOCs which offgas from materials
such as flame retardants and various other chemicals used in their manufacture.
Besides the above there are many other sources of VOCs within the average office building or
other communal building. These include air fresheners, personal care products such as
deodorants and perfumes, and laundry detergent and fabric softener residues on the occupants
clothing.
For a more detailed look at some of these VOC sources see our multiple chemical sensitivity (MCS)
page.
Heavy metals
Although much has been done to reduce or eliminate the use of heavy metals in buildings in over
the past few decades, older buildings may still contain a significant amount of these highly toxic
substances. Buildings built or extensively renovated after the early 90's in most developed
countries are not likely to have a problem, but many buildings constructed before this time could
pose a risk for heavy metal poisoning. The two most common heavy metals present in buildings are
lead and mercury.
Indoor paint manufactured before 1990 and outdoor latex paint manufactured before 1991 may
contain mercury, which was added to paint mainly to prevent build up of mold on walls, as mercury
is an effective antifungal agent. Mercury can damage health in a number of ways, from impairing
detoxification to causing serious neurological damage and birth defects. In fact, the mercury
containing compound thimerosal was routinely added to vaccines to prevent contamination by fungi
and bacteria until concern about its role in causing autism recently lead to its removal. Mercury may
also be present in small amounts in computer and electronic equipment.
Lead is another common problem in older buildings because it was also added to paints until a
couple of decades ago. Lead-based paint is still a major problem in older buildings particularly
when the residues are disturbed and become airborne such as during renovation or construction
projects. Like mercury, lead can cause severe neurological damage and a host of other problems.
Unless disturbed by renovation it's unlikely that heavy metals would be a major contributor to cases
of sick building syndrome. For older buildings the risk is there however so must always be
considered.
Biological Pollutants
As well as the chemical pollutants described above, various biological contaminants often
contribute to cases of sick building syndrome. In fact biological factors are reported to be behind
the majority of cases. These biological pollutants can cause illness through three different
mechanisms:
•Infection
•Allergy/Hypersensitivity
•Toxicosis - symptoms caused by toxins produced by micro-organisms e.g. mycotoxins produced by
mold/fungi
There are many sources of biological pollution that can affect a building and many reasons why a
building might become contaminated and cause illness in its occupants. The following are the main
sources of this form of pollution:
Toxic Black Mold - is reported to be the leading cause of sick building syndrome and building
related illness. Mold grows rapidly in warm and damp environments. If the indoor environment is too
humid or if water damage occurs through leaks or rising damp, mold growth is very likely to occur.
Viruses & Bacteria - are common in every building, especially high occupancy buildings such as
offices and schools. These micro-organisms can make a significant contribution to causing SBS.
They become increasingly problematic if humidity levels are either too low or too high, as a result of
how their growth is affected and the fact that our defenses against them are also affected by
humidity levels.
Dust Mites - are highly allergenic and thrive on the constant supply of shed human skin cells that
accumulate in carpeting, soft furnishings, and other areas. Like mold and bacteria, dust mites like
the warm and relatively humid environment that we usually provide in our buildings.
Pollen - is another allergy causing substance that can accumulate in a building if proper ventilation
and filtering is not maintained. Pollens from various trees and plants can be troublesome for a
great number of people. Aside from being carried on breezes through open doors or windows,
pollens can also be brought indoors on the occupants shoes and clothing.
Insect Body Parts - although not well known are especially potent allergens for some people.
Cockroach allergens are particularly troublesome allergens and are commonly implicated as
contributors to sick building syndrome. Usually become a problem only when sanitation is poor.
The above are collectively known as bioaerosols. The common definition of a bioaerosol is any
extremely small living organism or fragment of living things suspended in the air. They cannot be
seen without a magnifying glass or microscope. Of course when a large growth of mold occurs, it
does then become visible to the naked eye.
Reasons For a Building Becoming Contaminated by Bioaerosols
Moisture
The primary reason why bioaerosols become a major problem in buildings is the presence of damp
in the buildings structure and/or a high level of humidity in the air. There are numerous reasons
why such a situation could arise, some of the most common being:
•Water damage to homes from flooding or storm damage.
•Leaks in plumbing, roofs, or from air conditioners or HVAC systems.
•Condensation on central air pipes, HVAC components, or other cool surfaces where insulation
may not be present, is insufficient, or has become damaged. Uninsulated air conditioning coils or
pipes will "sweat" the most when hot humid air contacts them such as during warm months.
•Ice damming on building roofs which allows water to seep under shingles and through roof
sheathing.
•Dehumidifiers and humidifiers.
•Pets
•Moisture from unvented or poorly vented kitchens and bathrooms.
•Poor insulation causing drafts or the "chimney effect".
•Defective heating and air systems such as clogged condensation drain lines and full drip pans.
Hygiene and Cleaning
Poor sanitary and cleaning practices also contribute to a building becoming contaminated with
bioaerosols. In a high occupancy building for example, germs from bathrooms can easily be spread
to the rest of the building if they are not cleaned and disinfected both effectively and regularly.
People not washing their hands after using the bathroom can also be a big problem.
Another problem is often inadequate or poorly maintained cleaning equipment. A poorly functioning
vacuum cleaner for example can do more harm than good by spreading dust around rather than
picking it up. As we have heard, dust is a breeding ground for micro-organisms like dust mites that
cause allergies in many people. It may also contain other allergens such as pollens that have either
blown into the building or been carried in by the occupants. Dust may also harbour disease causing
bacteria and other unpleasant organisms. Efficient vacuum cleaners are thus essential pieces of
equipment for avoiding a sick building. Models equipped with HEPA filters which remove even the
tinniest particles are infinitely preferable.
Going back to chemical pollutants, growing research shows that chemicals, such as flame
retardants that are commonly used in electrical equipment and on furniture, accumulate in dust. If a
building is not kept free from dust by regular and effective cleaning, the amounts of chemicals
present will only increase and pose an ever greater risk for the occupants health.
Other Factors That May Contribute to Sick Building Syndrome
Besides the more obvious chemical and biological pollutants that are commonly present in buildings
and can lead to SBS, there are a number of more subtle factors that can also contribute,
sometimes significantly. The most common of these are:
Fluorescent Lighting and Electrical Equipment - People commonly report feeling unwell after
spending time in buildings lit entirely with fluorescent strip lighting. The flickering light is very harsh
and tends to give even otherwise healthy people headaches and make them feel drained. Many
people also complain of feeling unwell when they spend time close to computer screens and other
electrical equipment. It has been suggested that high frequency electromagnetic fields (EMFs)
which are generated by electrical equipment and a building's wiring can cause a host of unpleasant
symptoms such as fatigue, headaches, and inability to concentrate. Electrical Hypersensitivity
(EHS) is the term used to describe the condition in which people are made ill by electromagnetic
radiation.
Temperature - Although many would dismiss the ambient temperature within a building as a minor
consideration, an environment that is either too hot or too cold can have a major effect on how
people feel. With extremes of temperature the body has to work hard to maintain its own internal
temperature at the right level. With resources focused on this task people can quickly become tired
and drained and experience a wide range of symptoms. If the temperature is too hot for prolonged
periods for example, people can become dehydrated with potentially serious consequences for
their health.
Humidity - again can put a strain on the body as it tries to maintain equilibrium. Like high
temperature, a very humid environment can lead to dehydration and associated problems.
Noise - is an equally important factor. Too much noise can be draining and produce headaches
and other symptoms. It also makes it hard to concentrate so impacts on the productivity of workers
in an office for example.
Bad Office Design/Ergonomics - A badly designed workplace can cause numerous health
problems. A cramped office with uncomfortable furniture can result in injuries such as those to the
back as well as injuries such as repetitive strain injury (RSI) from repetitive tasks such as typing.
Stress - is another important consideration in an office building in particular. Stress can be caused
by work pressures such as deadlines but also by all of the other factors we've discussed here that
often relate to a building's design. Stress is a leading cause of absenteeism as it can result not only
in psychological distress but also many physical ailments as well.
What Can be Done About Sick Building Syndrome?
If you and other people living or working in the same building experience health problems that seem
to only be present when you are in that building, or at least get much worse, then it is reasonable to
suspect sick building syndrome. You should report the situation to the landlord, office manger, or
whomever is responsible for the building and ask them to have an inspection carried out. If they are
unwilling to cooperate then you may have to get local authorities such as an environmental health
agency involved.
After a thorough environmental health inspection is carried out on a building to determine possible
causes for the occupants health complaints, there are many measures that can be taken to rectify
the situation. A combination of some of the factors we've discussed above will usually be involved
and all will have to be tackled. Measures taken may include an overhaul or replacement of the
ventilation system, structural repairs to prevent leaks and damp, a review of chemicals used in the
building, a review of cleaning practices, and professional mold removal.
The important thing is to take action to have a suspected sick building investigated as soon as
possible as it is likely that the problem will only get worse if not addressed.