musingsheader image
0 Helpful?

Helping People With Multiple Chemical Sensitivity

Also known as idiopathic environmental intolerance, the diagnosis is controversial — and determining house design guidelines for these clients is tricky

Posted on Jun 17 2011 by Martin Holladay

If you are a designer or builder specializing in green building, it’s only a matter of time before you are approached by a client who suffers from multiple chemical sensitivity. A typical request might go like this: “Many ordinary building materials can make me sick. I’m looking for someone to design (or build) me a house without any toxic chemicals.”

What’s the best way to respond to such a potential customer? To answer this question, let’s turn first to the medical experts.

Looking at the science

Medical research never rests, and our understanding of medicine is still evolving. That said, it is always valuable to look at the latest conclusions of scientific research to determine where we stand now. Although our medical knowledge may improve in the future, any conclusions we reach today can only rest on the best current data available.

For a summary of the medical community’s understanding of multiple chemical sensitivity, I recommend “Overview of Idiopathic Environmental Intolerance (Multiple Chemical Sensitivity),” by Donald Black and Scott Temple. Last updated on January 28, 2010, the paper by Black and Temple is published by, a subscription-only Web site used as a reference by physicians.

Black and Temple explain that in 1996, attendees at a World Health Organization conference in Berlin proposed that the term “idiopathic environmental intolerance” (IEI) be substituted for the collection of symptoms formerly referred to as “multiple chemical sensitivity.” (“Idiopathic” means “of unknown cause.”)

Black and Temple note that idiopathic environmental intolerance “is a subjective illness marked by recurrent, nonspecific symptoms attributed to low levels of chemical, biologic, or physical agents. These symptoms occur in the absence of consistent objective diagnostic physical findings or laboratory tests that define an illness. Many experiments and observational studies consistently identify psychopathology in patients with IEI, and implicate behavioral or psychiatric causes for this illness. This indicates that the underlying illness in many cases of IEI is actually a psychiatric disorder, such as a somatoform, depressive, or anxiety disorder.”

Diagnosis by clinical ecologists

Many people claiming to have multiple chemical sensitivity have diagnosed themselves. Others, however, have visited physicians who call themselves “clinical ecologists.” Clinical ecology is not a recognized medical specialty, nor is the field part of a standard medical school curriculum. According to Black and Temple, these clinical ecologists assert that multiple chemical sensitivity “is acquired, highly prevalent in the general population, and goes unrecognized by most other clinicians.”

Most medical authorities have concluded that idiopathic environmental intolerance is not a recognizable syndrome. Black and Temple write, “Criticisms of IEI as a distinct medical entity include the lack of reliable case definitions; the lack of consistent physical abnormalities and reproducible laboratory results; the use of unorthodox diagnostic procedures; and the use of unproven and potentially harmful treatments.”

Those who suffer from multiple chemical sensitivity differ from patients exposed to toxic substances. “Toxicity due to certain chemicals such as lead and arsenic is well established, including the signs, symptoms, and pathophysiology of the disease states that occur following exposure,” write Black and Temple. “No such information exists for IEI despite many years of research. Prominent medical societies view IEI with marked skepticism. As an example, the American Medical Association concluded that, ‘Until such accurate, reproducible, and well-controlled studies are available, the American Medical Association Council on Scientific Affairs believes that multiple chemical sensitivity should not be considered a recognizable syndrome.’ ”

Severe reactions to sham provocations

Many researchers have studied these patients. “Multiple review studies have consistently failed to find a systematic connection between exposure to environmental triggers and onset of IEI symptoms,” Black and Temple point out. “Provocation studies that exposed patients with IEI to different substances found that patients could not distinguish between active and placebo substances when blinding or masking was adequate. Some patients with IEI exhibited severe reactions to sham provocations, which in one study were so extreme that the trial had to be terminated.”

Attempts to pin down IEI have been hampered by the multiplicity of symptoms exhibited by patients. “The symptoms of IEI are diffuse, nonspecific, ambiguous, and common in the general population,” write Black and Temple. “In one study, 295 patients with IEI reported 252 different symptoms. There are no essential differences in symptoms between patients who meet criteria for IEI and those who do not.”

Black and Temple conclude, “Although there is some disagreement whether IEI is a toxigenic or psychogenic illness, the evidence strongly demonstrates there is no immunologic or other biologic basis for IEI and that psychopathology causes the symptoms of IEI in at least some if not most cases. … IEI is not a distinct, valid medical entity. Symptoms lack specificity, there is no reliable case definition or set of diagnostic criteria, and there are no consistent objective diagnostic physical findings or laboratory tests.”

Professional groups are openly skeptical

The paper by Black and Temple represents the consensus conclusion of the medical community. Writing in Environmental Health and Preventive Medicine, January 2003, Mitsuyasu Watanabe, Hideki Tonori, and Yoshiharu Akizawa reached a similar conclusion. They wrote, “The Council on Scientific Affairs of the American Medical Association, the American College of Physicians, the American College of Occupational and Environmental Medicine, and other professional groups have all issued position papers that are openly skeptical of multiple chemical sensitivity/idiopathic environmental intolerance (MCS/IEI) as a distinct medical entity.”

In a 1998 paper called “A close look at ‘Multiple Chemical Sensitivity,’ ” Dr. Stephen Barrett wrote, “(1) MCS has never been clearly defined, (2) no scientifically plausible mechanism has been proposed for it, (3) no diagnostic tests have been substantiated, and (4) not a single case has been scientifically validated. For these reasons, MCS is not listed as a diagnosis in standard medical textbooks or the International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM), which is the standard manual used for classifying medical conditions.”

Fortunately, diagnosis and cure is not my job

Although I have described the consensus conclusion of the mainstream medical community — one based on the best available data and research — it is not the only conclusion. A minority of physicians, including those who call themselves clinical ecologists, have reached different conclusions.

If you are a designer or builder, the disagreements in the medical community over multiple chemical sensitivity don’t really concern you; nor does it matter much whether the symptoms experienced by people with this diagnosis have a chemical or a psychiatric cause. Your issue is a narrower one: namely, will my company be able to fulfill the expectations of this potential client?

What are you getting yourself into?

Before taking on such a client, it’s useful to read as many construction case studies as possible. One such study can be found on a Web page maintained by the Healthy House Institute: “In early 2007 Kevin and Kathy Christopherson set about building a home in Hanover, Wisconsin. This was no ordinary new home construction, though. Since Kathy has an acute chemical sensitivity, special precautions were necessary — precautions that presented particularly challenging construction issues. … Since people suffering from chemical sensitivity can have negative reactions to even minute amounts of certain chemicals, Nelson instructed contractors and subcontractors to empty their work trucks of all non-approved materials and tools prior to entering the jobsite to prevent their accidental introduction to the home. Also, all sheet metal used in the home had to be scrubbed to remove any oils on it.”

Creating a “safe” home for clients with multiple chemical sensitivity is complicated by the fact that the list of possible irritants is so long. According to “Profile of Patients with Chemical Injury and Sensitivity, a paper by Grace Ziem, MD, published in Environmental Health Perspectives, 1997, “Agents whose exposures are associated with symptoms and suspected of causing onset of chemical sensitivity with chronic illness include gasoline, kerosene, natural gas, pesticides (especially chlordane and chlorpyrifos), solvents, new carpet and other renovation materials, adhesives/glues, fiberglass, carbonless copy paper, fabric softener, formaldehydeChemical found in many building products; most binders used for manufactured wood products are formaldehyde compounds. Reclassified by the United Nations International Agency for Research on Cancer (IARC) in 2004 as a “known human carcinogen." and glutaraldehyde, carpet shampoos (lauryl sulfate) and other cleaning agents, isocyanates, combustion products (poorly vented gas heaters, overheated batteries), and medications (dinitrochlorobenzene for warts, intranasally packed neosynephrine, prolonged antibiotics, and general anesthesia with petrochemicals).”

Recommendations to architects and builders

If you are tempted to take on a client with multiple chemical sensitivity, here are some guidelines:

  • Don’t give health advice. Remember, you are not a doctor.
  • Don’t make any health claims for a house you build.
  • Don’t propose specific materials as “safe.” It’s better to say, “If you or your doctor provides a list of the substances that need to be avoided, I’ll do my best to comply with that list.”
  • Manage expectations from the start. Make no promises related to your client’s symptoms.
  • Be sure to include a great deal of extra time in your construction schedule for materials research and selection. A useful resource with information on the ingredients found in building materials is the Pharos database maintained by the Healthy Building Network.

Before deciding to work with a client with multiple chemical sensitivity, it's worth pondering the fact that (according to the best available data) these patients rarely improve. “The condition is highly stable and most patients remain chronically ill. A prospective study of 49 patients with IEI symptoms found that 92 percent remained ill after one year,” wrote Black and Temple. “Other studies have found that 54 to 96 percent of patients with IEI symptoms were unchanged or worse when they were reassessed several months to two years after their initial evaluation.”

What materials should be avoided?

Since some people with multiple chemical sensitivity become ill when they smell shampoo, it’s basically impossible to come up with a list of “safe” building materials. That said, here are oft-repeated recommendations noted by other writers:

  • Ceramic tile is better than carpet.
  • Linoleum is better than sheet vinylCommon term for polyvinyl chloride (PVC). In chemistry, vinyl refers to a carbon-and-hydrogen group (H2C=CH–) that attaches to another functional group, such as chlorine (vinyl chloride) or acetate (vinyl acetate)..
  • Low-VOC paints are better than conventional paints.
  • Solid-wood furniture or cabinets are better than furniture containing particleboard or plywood.
  • It’s best to omit wood-burning stoves and fireplaces.

It's worth considering the advice provided by building scientist Josesph Lstiburek: “When we design buildings for ‘sensitive clients,’ we typically put material samples in a bell jar and put them outside in the sun for a couple of days and let the clients ‘sniff’ them. We repeat the process with a little bit of water in the jar. If they don’t bother the client, they go in the building. Much better than trying to get anything useful from a MSDS sheet.”

An invitation to GBA readers

Have you worked with clients with multiple chemical sensitivity? If so, please share your stories with the GBA community by posting a comment below.

It would be interesting to know, for example, if the construction project was smooth or bumpy, and whether the clients were pleased with the completed project.

More information

For a balanced presentation of the issues discussed in this blog, see “Multiple Chemical Sensitivity (MCS): The Controversy and Relation to Interior Design,” by Linda Nussbaumer.

Last week’s blog: “How Is a Home’s HERS Index Calculated?”

Tags: , , ,

Jun 17, 2011 11:27 AM ET

Prefab Construction
by Nicholaus Baxter

I imagine it might be frustrating to work with a client with such sensitivities as some people, it seems, can never be satisfied. I think the recommendations and materials to avoid sound like a great start. If I had a client like this I would suggest prefab construction to them. This allows the building to be constructed in a dry and clean environment, which should also help create a healthy building. I would take cues from hospitals, as hospitals are some of the cleanest most well ventilated buildings around. If your client is not sensitive to the environment of a particular hospital, that might be a good starting place when looking at materials, lighting, and ventilation. Many new hospitals have lots of public documentation available about the steps they took to create , comfortable, healthy buildings.

Jun 17, 2011 12:28 PM ET

Another resource
by Sandra Heiser

An excellent resource for guidance with working with clients with sensitivities is "Prescriptions for a Healthy House" by Paula Baker, AIA.

I have environmental sensitivities that have impacted every aspect of my life. I know what triggered the sensitivity, and politely disagree with the finding of the medical establishment. The phasing out of formaldehyde in building products is an acknowledgement of the potential health risks chemicals can have. For those in the population that have compromised immune systems, chemicals and naturally occuring environmental elements such as mold can be debilitating.
The challenge in building a house for a client with sensitivities is that each individual has different sensitivities. One suggestion we make is that a client 'spend time' with a potential building material to see if there is a reaction to it. This is done in an environment that they know to be 'safe', such as their bedroom, so there is not the possibility of something else triggering a reaction.

Jun 17, 2011 12:52 PM ET

Safe room
by Jim Merrithew

Hello Martin
In the 1980s, on a photo assignment for Harrowsmith Magazine, I photographed a home built by Oliver Drerup. The house was built to accommodate the environmental sensitivity of the lady of the house. In order to ensure the woman would not react to any building products, she had to approve every item or element. This meant exposing her to each article individually to see if she reacted.
He built her bedroom as a safe room. It had its own ventilation system and was furnished minimally. You would get a much more complete explanation from Oliver who now works for C.M.H.C. in Ottawa.

Jun 17, 2011 1:23 PM ET

Personal experience with MCS clients and Transparency
by Brennan Less

Martin, good summary of the current scientific research; I will definitely dig into the papers you listed. I have worked with a number of MCS people on construction projects, and it can be a challenging and sometimes rewarding experience. But it requires exceptional levels of patience.

I would add to your list of recommendations for designers, contractors, etc. People with MCS usually require direct exposure to building products, in order to ensure they don't react. For example, in specing interior paint, your MCS client will likely need to directly smell/be-exposed-to a variety of uncured options--all of which are "green" or 0-voc. As their building professional, you can either lead them through this process or they can lead themselves through the process. Again, this requires high levels of patience a A LOT of time.

You mention that they should provide a list from their doctor. This is an impossible request, as their doctors usually have no idea what will cause reactions and in what combination. Plus, few MCS patients actually have sympathetic, knowledgeable medical professionals at their side. So, I think that some MCS sufferers have their own list, which can be useful (but not always), but I've never met one with a legit list from a doctor.

I would also add that the devil is ALWAYS in the details when working with MCS sufferers. You recommend tile over carpet (which I agree), but that's not enough, you need to know what grout is acceptable, what grout sealer, what mortar/mastic, what underlayment, what the glazing is on the tile...on and on.

To anyone working with an MCS client, I recommend using the PHAROS database ( from the Healthy Building Network, which is the ONLY database available that truly demands ingredients/product transparency for participating manufacturers. Currently, there is no more reliable source of information for the contents, toxicity and health attributes of building products. I encourage you to support their efforts pushing for transparency...of course, this is valuable for all owners/building professionals, not just for MCS cases.

Jun 17, 2011 1:30 PM ET

Edited Jun 17, 2011 1:39 PM ET.

Response to Brennan Less
by Martin Holladay

Excellent advice, Brennan. I appreciate your feedback. I think I'll add an item to one of my bullet-point lists: "Remember to include a great deal of extra time in your construction schedule for materials research and selection."

I'll also add a link to the Pharos database. Thanks again for the suggestions.

Jun 17, 2011 2:43 PM ET

Edited Jun 17, 2011 2:53 PM ET.

Is "Medical Convention" the same as "Building Convention?"
by Matt Dirksen

Not long ago, I met a potential client with severe chemical sensitivities who was looking to remodel his kitchen. He has been on permanent disability for about the past decade due to being exposed to toxins during a building renovation at his office (the EPA of all places). He was one of many co-workers who became permanently sick due to that particular catastrophe. If I recall, all of his coworkers reacted differently to the exposure, some benign, some severe.

As a professional who practices as much green building as I can: why should I inherently trust "Conventional Medical Opinion" any differently than I trust "Conventional Building Opinion"? This isn't about being "distrustful", but about being open minded. If the authentic green builders represent a fraction of the builders out there, then I must ask myself who the “fraction” of medical professionals exist out there who think the same way I do, but in medicine? For example; The Environmental Working Group just came out with their list of fruits and vegetables which are most likely to contain pesticides, unless I buy organic. Some medical professionals will scoff at this data right off the bat. They will say that you have a better chance of getting hit by a car, than developing anything from this minute amount exposure. Even if some of the samples came back with less ppm than what the EPA threshold mandates, how should I react to this – especially as a “green practitioner”? Is it only about my personal health, or the principle of pesticide use, or both?

Thanks, Martin, for bringing this conversation to the fore front. I feel like 75 percent of any discussion about “Green building” always has to do with energy efficiency. The next 10 percent is on recourse efficiency. Finally, it seems we focus only five percent or our energy on everything else, including health and wellness. It seems to me that if there is any “white elephant” in the green building world, it is clearly in our apparent lack of understanding (or fear of trying to gain better clarity) on the health implications and impact of what we do.
I am wondering if this is due to our reliance on “trusting” conventional medical wisdom for our answers, instead of looking toward those in the medical profession who are actually looking a little further down the road than most do – just like we do in the building world. The discoveries in medicine are just as dynamic and ever changing as they are in our industry. Back in the day; was the medical “profession” able to raise any alarms about installing / applying products with lead & asbestos in our homes? Could they have been at that time? If not then, how do I know they are there today?

My personal reasons for practicing green building techniques run much deeper than simply being about construction. My sense is that this is the case for many of my companions in the green world. If this is the case for you, I would sincerely hope that you strive for a deeper understanding of the professions related to green building, whether they are “proven” or “emerging”. There are many people in the world of MCS who I suspect would be delighted to share with you their personal experiences, and who likely vehemently disagree with Dr. Barrett’s research findings. I have talked to some in the MCS world who were downright offended by Barrett’s inference that their symptoms are psychologically driven.

All this proves to me is the medical world has as much to learn about medicine as we do about building.

Jun 17, 2011 2:52 PM ET

From Retired Medical Adviser, U.S. EPA
by Lawrence Plumlee

The chemical industry has attempted to discredit clinicians who diagnose illness caused by profitable, commonly used materials. The sources that Martin Holladay cites are supportive of that industry viewpoint. In the most chemically sensitive patients, who are the ones seeking to build a safer home, there is sometimes a fear that it will be difficult to build the home that they need. But chemical sensitivity is not a psychiatric illness. Like a canary in a coal mine, these patients usually point to toxic problems that will benefit others when corrected. Builders themselves may experience less fatigue using materials that are not evaporating toxic chemicals.

Jun 17, 2011 2:53 PM ET

Response to Matt Dirksen
by Martin Holladay

You've asked a good question: "Why should I inherently trust 'Conventional Medical Opinion' any differently than I trust 'Conventional Building Opinion'?"

Here's my answer: I believe in the scientific method. That's why I listen to building scientists rather than NAHB. Here's how building scientists have been helping improve our understanding of building performance: they have been using physics and data collection and research to refine our understanding. The reason that energy-efficient builders are now able to build much better homes than tract builders in the 1960s is because of the pioneering efforts of researchers who believe in (and use) the scientific method.

Fortunately, medical science in the U.S. is firmly based on the scientific method. This is different from the way medicine was practiced in the Middle Ages, when anecdote and prejudice informed doctors, rather than data and research.

I've done my best to summarize what the best current data and research tell us about MCS, otherwise known as IEI. There will always be people who scoff at the scientific method, and prefer other methods of understanding, such as gut instincts. For me, though, I'd much rather stick with the scientific method, based on data collection, research, and reproducable results.

Jun 17, 2011 2:56 PM ET

Response to Lawrence Plumlee
by Martin Holladay

You may well be right that some chemical engineers and employees of chemical companies "discredit clinicians who diagnose illness caused by profitable, commonly used materials." However, I am not one of them.

Just because their motives are suspect does not mean that mine are. I am basing my reporting on the best available medical data and research by physicians who don't have a dog in this fight.

Jun 17, 2011 3:04 PM ET

Great line of thought Matt
by Brennan Less

Martin, I have to support Matt Dirksen's argument about conventional wisdom in building and medicine. The scientific method, while a powerful tool for critically examining our world, has many faults. Science is always a consensus-based exercise, and in almost no cases is it free from biases. The scientific method can only be as good as the measurement protocol and data that are used in the process. It very well may be that we simply don't know how to measure what is happening to MCS sufferers, or how to quantify or fully explain it.

Ultimately, who cares about the scientific consensus? MCS sufferers are in very real pain and discomfort regularly (whether the cause is psychological, physical, environmental, or other). The obvious response, as their building professionals, is to respond to their needs, as they believe them to be, in whatever way you can.

Jun 17, 2011 3:11 PM ET

Second response to Brennan Less
by Martin Holladay

I agree completely that it's not necessary for builders to resolve this medical dispute.

That's why I wrote, "If you are a designer or builder, the disagreements in the medical community over multiple chemical sensitivity don’t really concern you; nor does it matter much whether the symptoms experienced by people with this diagnosis have a chemical or a psychiatric cause."

Jun 17, 2011 4:18 PM ET

More on the scientific method
by Martin Holladay

For those of us who believe in the scientific method, it's frustrating and sad that 380 years after Galileo's heliocentric description of the solar system led to his prosecution for heresy by Pope Urban VIII, the scientific method is still a beleaguered orphan in the U.S.

Suspicion of the scientific method is frequently heard on television, on the street, and at office water coolers. The distrust of medical research expressed on this page is only one aspect of this general suspicion; its most pernicious eruption can be seen in popular distrust of scientists' warnings about global climate change.

Jun 17, 2011 11:07 PM ET

Science and Chemical Sensitivity
by Lawrence Plumlee

Science is usually expensive, so most science on chemical sensitivity has been done by those who have money and an economic incentive to prove that it is not neurotoxicity. Clinicians generally want to heal, not do research, and they are unlikely to do scientific research to prove it is a toxic illness. Academicians often try to avoid research that is likely to engender attacks from wealthy adversaries.
Medical Journals discriminate against research that their advertisers find objectionable. So science about chemical sensitivity is biased.

Jun 18, 2011 5:01 AM ET

Edited Jun 18, 2011 5:28 AM ET.

Response to Lawrence Plumlee
by Martin Holladay

As a journalist, I must I disagree with your claim, "Medical Journals discriminate against research that their advertisers find objectionable." This is an example of an unproved conspiracy theory -- an unanswerable world view.

Like the scientific method, journalism is in ill-repute (and much beleaguered) in the U.S. today. Your conspiracy-based view of journalism and medical research makes me sad -- and, as I said, it is a fundamentally unanswerable position.

Jun 18, 2011 7:03 PM ET

Edited Jun 18, 2011 7:05 PM ET.

Martin's response to Lawrence Plumlee
by Joseph Morgan

After over 40 years of dealing with individuals suffering from MCS, I agree with everything Lawrence has said and must respectfully disagree with your comments above. There are dozens of documented examples supporting Lawrence's assertions. For scientific validation of MCS and explanation of the physiologic mechanisms please see General and Applied Toxicology, 3rd Edition, Chapter 92: Multiple Chemical Sensitivities. This 6 volume text is the standard authoritative resource in the field.

Jun 20, 2011 8:59 AM ET

The Scientific Method
by Dorothy Parker

Martin, I am an environmental scientist and have been for a long time. I developed MCS at EPA, too and have had this illness for a long time. I also believe in the scientific method and have for a long time. Here's something else I believe in: medical and chemical research in this country is largely bought and paid for by people with deep pockets and deeper agendas. These people do not want you to know how seriously we are all affected by chemical exposures in our daily lives because they do not want to be held financially or otherwise responsible for the resulting health problems. The scientific method is no match for the almigthy dollar in this country. MCS is not a psychiatric illness and anybody who wants to learn more about it should definitely check outhe text mentioned in the previous comment.

That said, I agree with you - the only way to construct an acceptable structure for a chemically sensitive person is to engage in constant communication with the client, letting their feedback be your guide.

Note - I am not using my real name and I am not speaking as a representative of the EPA in this comment.

Jun 20, 2011 9:15 PM ET

Edited Jun 20, 2011 9:18 PM ET.

IAQ is not enough
by James Morgan

MCS is a potential minefield for designers and builders and Martin's warnings not to over-promise are to be well heeded, as all the usual rules of what we generally understand about healthy home construction may be out of the window with MCS sufferers. With all due respect to Mr. Baxter's 'dry, clean' factory conditions for prefab construction this shows no understanding for the nature of the problems faced by those who are not tolerant of almost any of the materials used in industrial building. And as a larger point which has yet to be mentioned, the more air-tight and energy-efficient homes to which we all aspire these days may be making matters much worse for them - not that the air outside the home is necessarily going to be any better.

My own fairly limited experience with MCS clients has been somewhat satisfactory especially for those with milder symptoms but it has also included the following:

• A potential client who interviewed by telephone as she could not venture to my office for fear of reactions: after several weeks of research we could not even establish basic structural strategies: even wood framing was off limits because of sensitivity to the natural resins. Without clarity about even the most basic constructional materials I could see no opportunity for a reliable outcome and ultimately I declined the project. Her home at the time of our interviews was a standard commercial condo in which her life must have been miserable. I gathered later that none of the other architects and builders she contacted was able to do anything for her either.

• A client couple with whom we completed both the design and construction of a home at a time when we had to do extensive research to find formaldehyde-free and low-VOC materials (much easier now, of course), nevertheless we did that research and hit all the bases, or so we thought. During construction the portajohn even had to be cleansed with special (expensive) low-odor cleaners, though it was located a good fifty feet from the home and there was no expectation of use of the facility by the homeowners. The layout included a large mud room where the husband could completely disrobe and shower and wash all his clothing on returning from the office so as not to bring any potential contaminants into the home. We employed all the best practices of indoor air quality that we knew including HEPA filter, top-quality insulation, duct-sealing, etc. etc. Nevertheless the homeowners declined to move in, left it empty for a year and a half and then sold it. The most frustrating part of the exercise after all the care we put into it was that they continued to live in their original home, a 1980's tract house with twenty-year-old carpet.

I found myself wondering if perhaps that clearly substandard home was nevertheless tolerable because it was good and leaky and all the original materials, whether 'natural' or synthetic, had fully out-gassed. For some MCS sufferers could new construction in and of itself be part of the problem?

Jun 21, 2011 5:04 AM ET

Edited Jun 21, 2011 5:06 AM ET.

Response to James Morgan
by Martin Holladay

Thanks very much for sharing your experiences, which should prove helpful for any designers or builders who are trying to decide whether their companies can help clients with MCS.

I've been involved with efforts to lower air leakage in existing buildings and new homes for many years, as a builder, a project manager, and a consultant. I'm noticing an increased focus lately on the question of whether lowering the air leakage rate of a building can reduce indoor air quality. There are even articles that crop up these days with headlines like, "Green buildings make people sick."

But in all those years, all of the energy experts I have encountered have been strong advocates of good mechanical ventilation systems, and have been advocating for the installation of HRVs and ERVs. In fact, the green builders and energy experts are far more likely than ordinary run-of-the-mill builders to understand the need for good mechanical ventilation systems. So I don't think the problem lies with green builders or energy-conscious builders, all of whom have been repeating the mantra, "Build tight and ventilate right" for decades.

Jun 21, 2011 6:03 AM ET

"I found myself wondering if
by Dorothy Parker

"I found myself wondering if perhaps that clearly substandard home was nevertheless tolerable because it was good and leaky and all the original materials, whether 'natural' or synthetic, had fully out-gassed. For some MCS sufferers could new construction in and of itself be part of the problem?"

Yes. Most materials offgas to acceptable levels eventually if there is somewhere for the pollutants to go. In my experience, older is often better as long as there has been no mold or other contamination. The most persistent substance I have come across lately is microban/triclosan (an antimicrobial agent that is being added to numerous consumer and commercial products in the US these days).

Jun 21, 2011 9:34 PM ET

'Build tight and ventilate right'
by James Morgan

Agreed. No wish to suggest or imply that poor construction standards should be the fix for MCS problems. But perhaps that MCS sufferers just might do better in a well-built well-maintained home that's a few years old than in a brand new one? If, of course, you're lucky enough to find one.

Jun 22, 2011 10:13 PM ET

Martin, if you are most
by charles CAMPBELL

Martin, if you are most swayed by the scientific method, don't form your opinion until you have read the science presented by another Martin in

Jun 23, 2011 4:23 AM ET

Response to Charles Campbell
by Martin Holladay

I think I'll pass on this $95 book for now. However, while Googling the title, I did find a link to a useful document: Scientific Review of Multiple Chemical Sensitivity.

The review notes, "The literature relating to causes of MCS invariably highlights differences in views regarding the primary underlying cause of MCS -- ie. psychogenic or toxicodynamic. There is much debate as to whether MCS symptoms are due to psychosomatic response to perceived chemical toxicity or to a physiological/pathological interaction between chemical agents and organ systems. While some physicians believe MCS is purely a psychological disorder, others consider it to be an overt, albeit poorly understood, physiological response to chemical exposure. It is also possible that both physiological and psychological factors play a part in the pathogenesis of MCS. Despite, or perhaps because of this debate, the underlying biological basis for MCS and its range of variable symptoms remains unresolved."

Jun 23, 2011 6:34 AM ET

LOL. Apparently, I'm invisible but
by Dorothy Parker

I will say one more thing. The "debate" mentioned in the review is much like the "debate" over global warming/climate change. It was manufactured; created by corporate interests with a lot to loss should it ever be proven that they are responsible for willfully poisoning millions of people. Clearly, it is to the benefit of chemical manufacturers to label the people they have poisoned as having some sort of psychological problem. I repeat - they do NOT want to be held financially or otherwise liable for their actions. Perhaps you don't care about what a scientist with a long career at EPA has to say on the matter but I know, better than most, how this system works. Believe what you want but if you want the truth, as always, follow the money.

Jun 23, 2011 8:26 AM ET

Edited Jun 23, 2011 8:28 AM ET.

Response to Dorothy Parker
by Martin Holladay

I do care what a scientist with a long career at EPA has to say, Dorothy, but I remember in your earlier post that you told us that "I am not using my real name."

In the global warming debate, the 98% of scientists who have concluded that global warming has anthropogenic causes all use their real names.

You claim to suffer from the problem of invisibility. Using your real name might help you overcome that problem.

Jun 24, 2011 11:20 PM ET

not the last word hopefully
by j chesnut

I respect that you recognize that this issue is out there voiced by several readers of this website and you have taken time to dive a little deeper in order to offer builders practical advice.

My expectation for discussions concerning the impacts of various chemical compounds on biotic life is that it be discussed in scientific terms similar to how we discuss the physics of hygrothermal phenomena.

I'm not the expert chemist but I recall discussions of how for example Bisphenol A can transfer into a biotic system through water and be an endocrine disruptor. I recall a presentation by a chemist who left 3M to become an advocate for environmental responsibility because he became disenfranchised as he understood how classes of plastics produced polluted the environment (thought legally approved) and how plastics such as PVC had such a chemistry that heavy metals could transfer into the blood systems of those who handled the product often. Discussions like these, like your valuable body of work on the energy efficiency of buildings, could on a regular basis build the readerships knowledge of a difficult subject and be properly archived for easy reference.

There are potentially several real dangers out there and 'Multiple Chemical Sensitivity' is a unfortunate grouping of everything unexplained and inconvenient about real persons' physical reactions to constituents in the environment. I have attending many a workshop on the issue and I do believe there is an element of paranoia involved with certain individuals. But on the otherhand I believe that 'dirty' chemicals make it into our environments as useful and profitable products but only after the fact are any health impacts recongnized and dealt with.

With all due respect I don't believe you have the chemical expertise or the open-hearted concern (i.e. the 'dog in the fight') to properly address this issue as a GBA expert blogger. One last time I will appeal to you to seek an expert in chemical effects on biotic systems as a regular blogger for this web site. This is a proper subject for a site that claims to advise on 'Green' building and not just energy efficient building.

Jun 25, 2011 6:47 AM ET

Edited Jun 25, 2011 4:52 PM ET.

Response to J Chesnut
by Martin Holladay

Thanks for your comments. Like you, I certainly hope my blog on this subject is not the last word. GBA has been contacted by someone who suffers from MCS -- a physician -- who was offered the opportunity to write a guest blog for us on this topic. I hope she decides to accept the offer.

You're right: I'm not a chemist. I'm a journalist. (I'm not a physicist or a building scientist either, but I report on those topics).

You are also right that some substances are toxic. Avoiding toxic substances is one of the responsibilities of a green builder. Some of the best known substances that have harmed people in buildings are lead, asbestos, and formaldehyde. I used to be a certified lead abatement contractor in Vermont, and I take the danger of lead poisoning very seriously. It's not a joke. When I was a project manager for a series of rehab projects of low-income housing developments, we insisted that every step of the clean-up protocol and post-rehab lead-dust testing be performed exactly according to the specs, and I didn't hesitate to insist on re-cleaning and re-testing when required.

You're also right that industrial workers and manufacturing workers in chemical plants face special hazards. The manufacture of PVC is especially nasty. I once toured a Universal Rundle plant in Massachusetts where fiberglass tub/shower units were produced, and my (unscientific) reaction was that this wasn't likely to be a safe place to work. (Neither is the typical hair salon or beauty parlor, I wager, but that's another matter.)

From the literature I have read, MCS sufferers fall into a different category. They aren't responding to a known toxic substance; nor do they work in industrial settings.

I'd like to repeat what I wrote in the original blog: there are at least two sides to this issue, which continues to be debated in the medical community. The issue is unresolved, and future research may clarify the causes of the symptoms experienced by those with MCS. I'm not taking a stand on this issue, and -- as I wrote before -- it's not generally the role of a designer or builder to do so.

Thanks again for your perspective. I hope that a discussion of these issues continues at GBA, from all sides.

Jun 25, 2011 2:59 PM ET

additional perspective
by j chesnut

Thanks for your well considered response. I have underestimated your background and attitude towards the subject. From reading some of your responses to other blog entries on this website concerning the same subject I formed the impression that you were someone that needed to be convinced that this was a legitimate problem to be as thoroughly covered as energy efficiency.

My initial response to this blog was a convenient opportunity to appeal for further elaborations from experts with backgrounds in chemistry as additional content to this website. I found your practical advice to building professionals agreeable except maybe for placing the issue squarely on the authority of the medical community.

I hope to avoid cliches here between the differences between Eastern and Western medicine so I will quote Ted J. Kaptchuk a medical doctor trained first in the Western tradition and later moved to China to learn the Eastern traditions. His book 1983's "The Web that has no Weaver" is a level-headed description of the limitations and strengths of each system. For example:

"The two different logical structures have pointed the two medicines in different directions. Western medicine is concerned mainly with isolable disease categories or agents of disease, which it zeroes in on, isolates, and tries to change, control, or destroy. The Western physician starts with a symptom, then searches for the underlying mechanism - a precise cause for a specific disease . . .

The Chinese physician, in contrast, directs his or her attention to the complete physiological and psychological individual. All relevant information, including the symptom as well as the patient's other general characteristics, is gathered and woven together until if forms what Chinese medicine calls a "pattern of disharmony". . . The therapy then then attempts to bring the configuration into balance, to restore harmony to the individual."

I don't believe that there is an essential categorical difference to what MCS sufferers experience and the effects on the physiology due to known toxins. I believe as Sandra Heiser described in comment #2 that it is because of a constellation of factors (what she calls a 'compromised immune system) that MCS sufferers are severally affected by certain environments (in part composed of chemicals) while the majority of people are not noticeably affected.

Take this anecdotal example. My father a retired plumber at a later point in his career became severely "allergic" to epoxies. In proximity to epoxies, even without direct contact, he breaks out in rashes. This is obviously due to in part long term exposure to the product but many people with the same exposure levels have not developed these symptoms so there are other variables at work. I reason that epoxies strain all our physiological system. There are many different things in our environment that strain our health and this 'complex of relationships between the individual and the environment' falls more neatly into the concept of a "pattern of disharmony" as described by Dr. Kaptchuk.

I agree it is too complex an issue to expect a designer or builder to deem building products safe or unsafe. However we need to recognize that at some point in history with the advent of industrial chemical production products have been introduced into the market that are categorically different from pre-industrial building components. Yes some pre-industrial building products probably can be shown to adversely affect human health (as many techniques of heating did) but it is not like today where powerful profit driven motives can be behind the widespread distribution of products whose health and environmental consequences disproportionately affect some more than others. We profit from our professions and should consider that we have some responsibility in all this.

Jun 26, 2011 7:42 AM ET

addressing the main issue
by Jon Vara, Editor, EDU

I had hoped that someone would address the core issue: the experimental finding that people who are sickened by exposure to various substances--OSB, say--are not sickened unless they KNOW that they're being exposed. There are basically three ways to respond to such findings:

First, you can dismiss them by claiming that researchers (the "medical community") either ran the experiments incorrectly, or are engaged in a conspiracy to hide the truth, and have manipulated the data with that goal in mind. As has been pointed out, that response is unanswerable.

Second, you can further investigate the possibility that people are made ill by the knowledge that they are exposed to a substance, not by the substance itself. That is not to say that they are not made ill. People who suffer from MCS reject that for no good reason that I can see--it's as if they somehow believe that that mechanism it would mean that their illnesses are not "real."

Third, you can propose a new testable hypothesis. Does anyone have one to offer?

Am I missing anything?

Jun 26, 2011 8:31 AM ET

Response to Jon Vara
by Martin Holladay

Thanks for your comments.

There are other possible responses. Some MCS sufferers could respond, "Although some experimental subjects did not react to masked substances that caused reactions when the same substances were unmasked, I am not like such experimental subjects. I know that MY reactions would be consistent."

Jun 26, 2011 10:56 AM ET

True, but...
by Jon Vara, Editor, EDU

True, but in that case we're throwing science out the window again. The scientific method works by following the data where it leads. It doesn't work by saying, in effect, "I already know the answer, and since the data appears not to support my answer, the fault lies with the data." Maybe more and better data would provide a different answer, but the solution to that is more experimentation and more and better results, not a rejection of science.

Jun 27, 2011 6:39 AM ET

My real name
by Dorothy Parker

"You claim to suffer from the problem of invisibility. Using your real name might help you overcome that problem."

True, this is not my real name, as I openly stated. I also stated that I am not speaking as a rep of EPA. I thought, as a journalist, which you state that you are, you could read between the lines and perhaps respect my intentions and my need for privacy. I certainly was not expecting to be treated so rudely after participating in this discussion. You should remember that, when you post on the internet, you open yourself up to all sorts of feedback and comments. You might do well to adopt a thicker skin when responding to people who say things that make you feel defensive. Have a nice day.

Jun 27, 2011 6:46 AM ET

Edited Jun 27, 2011 8:24 AM ET.

Response to Dorothy Parker
by Martin Holladay

I respect your decision to post anonymously. However, you chose to identify yourself as a scientist and decided to enter into a debate on a scientific topic in a public forum. You also accused me of not taking your scientific position seriously.

Scientific debate requires openness, full disclosure of data and experimental methods, and a public give-and-take to sort reproducible findings from rumors and false claims. It's impossible to evaluate the claims of a scientist who remains anonymous.

The only reason I referred to your anonymity was because you raised the issue first. You wrote, "Apparently I'm invisible ... Perhaps you don't care about what a scientist with a long career at EPA has to say."

Jul 18, 2011 3:32 PM ET

Comments by Oliver Drerup
by Martin Holladay

[Editor's note: After Jim Merrithew posted an early comment on this page (“In the 1980s, on a photo assignment for Harrowsmith Magazine, I photographed a home built by Oliver Drerup. The house was built to accommodate the environmental sensitivity of the lady of the house. …”), I contacted Oliver Drerup for his recollections. Oliver responded to me by e-mail, and I am posting his comments below.]

Oliver Drerup wrote:

"First, my thanks to Jim Merrithew for remembering our work. Most appreciated. I would return the favor by asserting that he gave us some fine architectural photographs. Second, please let me make it abundantly clear that I am no expert on housing for the chemically sensitive. Everything I have learned about this dreadful malady I have learned from my clients. They are the final arbiter in these matters weather or not we understand their concerns. The problem with the murky science surrounding much of this, is that all too frequently it proves to have a basis in fact, which we have yet to learn about. I remember with considerable clarity the discussion I had with my plumber when I indicated to him that all the joints in the copper system we were about to install for a chemically sensitive client would have to be soldered with silver solder and how barkingly mad that made me appear. Years later, the plumbing code has disallowed 50/50 solder. Hum...

"The first project of this type which we took on was one we very much wanted because the client, in addition to manifesting serious sensitivities, also had refined taste and a robust budget. We had a small army of Renaissance men and women banded together in the company Allen-Drerup-White Ltd. and, frankly, we needed the work. Our attitude therefore was, 'If you have the money, I'll make the time'. If you want to very carefully sniff bits of building materials held in a bell-jar before pronouncing them suitable for use, I am willing to invoice for my time.

"One of the issues which we encountered was the concern for detergents in the environment. Detergents were not to be used!

"Imagine me, if you would, standing in the dispatch shack of our local ready-mix supplier determined to ensure that the concrete we were being shipped (and for which I required a letter of confirmation signed by the supplier) did not contain any water-reducing agents. At the time I had only recently learned about water reducing agents as a direct result of my clients concerns. For the uninitiated they are detergent additives which enhance the workability of concrete without the loss of strength associated with adding water. When conscientious builders provide sufficient accessibility to the form work being poured and are willing to ensure proper placement of the concrete, they are unnecessary. They make the job easier to do and are intended to serve the contractor not the not the homeowner.

"Several days later we were stripping the forms and all of us, included form workers with whom you would cheerfully cruise mean streets at midnight, were commenting on the fact that our eyes were not watering. This was something which we had assumed was a result of the cement itself and was just normal when you strip forms from recently poured concrete. Hum.......

"I can spare your dear readers the details associated with discovering that some vermiculite contains a pesticide, that the plasticizer used in certain colors of electric wire is worse than that used in others, that the use of naturally slaked lime finish requiring no paint is a dying craft, that washing the ductwork clean of oil and placing ventilation fans exterior to the airstream requires considerable effort. Most of these issues are covered by others in worthy detail elsewhere. All you need to know is that delivering the project was fundamentally challenging and that I learned many things about material science which I had not expected.

"But that, it seems to me, is the point. This is not actually about the application of the scientific method, which we all agree is desirable, or about the veracity of the medical establishment, which is surely as good as can be expected. At the end of the day, this discussion is about trying to build decent shelter much like a chef tries to prepare a decent meal.

"The problem is that we are all on the receiving end of increasingly complex lines of supply. In the industrialized countries these distribution chains are perhaps the most obvious mark of our current civilization. The global economy as an expression of the economic power unleashed by the medieval city-state, a result of specialization and the division of labor. Along these chains of supply, many decisions are made for the bottom line costs and marketability of products, which do not necessarily enhance the product itself. Tasteless tomatoes which ship well. Hybridized produce which resist herbicides that ruin soil fertility. Concrete which flows easily or perhaps colored wire because it makes sense to identify 220 from 110 or three conductor from two without recourse to the impact that plasticizers might have on certain canaries down our mine. Astronaut John Glenn is reputed to have answered a reporter inquiring what he was thinking while waiting for blast off by saying that he pondered on everything in the rocket having been provided by the lowest bidder.

"The world is not linear. Rather it is the confluence of intertwined materials and energy availability, industrial and banking interests, marketing and cultural attitudes. The creation of these complex supply streams intended to make our buildings better, safer and more affordable also encourage our manufacturers to move to China and create a debilitating domestic skills shortage.

"In the midst of all this, honing our ability to listen, particularly to the most marginalized voices in this debate, just might lead to a better understanding of the way forward.The knowledgeable and historically sensitive management of complexity remains the mark of a well educated and civilized person. I am sure you could get a lot of doctors and other scientists to agree with that.
--Oliver Drerup"

Jul 21, 2011 5:50 PM ET

Edited Jul 22, 2011 6:00 PM ET.

John and Kitty Nelms House
by Jim Merrithew

Hello Martin,

I had hoped that Oliver Drerup would expand on the details of the amazing house he built for John and Kitty Nelms.

Online, I found a transcript of a meeting where John described the process by which they eliminated products and how Oliver approached the build. This may be interesting to anyone involved in building a home for those who are chemically and environmentally sensitive.

I only visited the house for one day about 25 years ago, but I'll try to outline what I remember of the house and my discussion with Oliver and John.

The house was built with the defensive philosophy of a medieval castle. There were multiple layers of defense before one reached the keep, the inner sanctuary which was Kitty's bedroom. As with any good fortress, the first tactic was to pick a good location. As the transcript mentions, the property was in a rural location about 25 miles from the heart of Ottawa. The lot was 25 acres of trees, mainly cedar. The house was set back from the road. The first line of defense, the trees, filtered out any dust, agricultural chemicals and other pollutants. They also cleaned the air and produced oxygen.

At the entrance to the home, there was an airlock. While this is not unusual in an energy efficient home in Canada, this space did more than improve the home's thermal performance. It was a buffer zone. John was a successful businessman. Therefore, his suits required dry cleaning. His clothes hung in this closet which had its own exhaust fan to draw off any chemical offgassing, any odours or pollutants which his clothing might have absorbed at work. I recall that his work clothes did not enter the house proper. I think the airlock was under negative pressure.

The kitchen and other living spaces were spartan. There were very few of the nicknacks found in most houses. The cupboards were made of natural wood products. Any linens were also natural fibers. The plates, cups etc. were simple and ceramic or china (if my memory is accurate).

Kitty's bedroom was her sanctuary. It had its own fresh air and exhaust system. I believe the room was under positive pressure.

Oliver took me into the attic to show me what we would consider an early version of an air exchanger. He had developed an elaborate filter system to remove products such as dust, pollen, wood smoke, and other triggers.

I don't recall what John and Kitty used to wash and clean dishes or clothes and the house. Perhaps John or Oliver could add some info.

In spite of all of the restrictions on the materials and the steps required to protect Kitty, Oliver build a beautiful, comfortable and functional home.

Oct 27, 2011 5:45 PM ET

Not a builder but a sufferer
by Lisa Verlaan

Some of my symptoms are very visible; my fingers wrinkle like an old lady left in a bath tub for a couple of days, my skin gets red with very straight white lines in between and my eyes get swollen. It all happens in a split second, when I get exposed, and dissapears again as fast, when I'm not.

This is not an invisible disease...!

May 8, 2012 2:16 PM ET

MCS Safe Building Materials
by Kevin Royce

Yes building for those with MCS does have its struggles but those struggles are a drop in the bucket compared to those living with MCS.

May 24, 2012 12:22 AM ET

With friends like these
by Chris Brown

God help us from skittish professionals who do not understand the issues. A diagnosis of having sensitivities that can be disabling is not controversial. The thing that is controversial is the flaky explanations and questionable elements among the clinical practices of so-called doctors of environmental medicine who have attached themselves to this patient group. The US National Council on Disability's recent report on housing for disabled persons mentioned that 11% of the population requires reasonable accommodation for sensitivities.

Supportive professionals, and they are not rare, need to get over their David vs Goliath complexes and know that sensitivities have been known to clinical medicine for at least 1000 years, they are covered in 300 years of Western medical literature, they have been covered under disability and human rights law in the US, Canada and many other countries for decades.

The idea that sensitivities are new or questionable is just one of the myths that are faced by people with these age-old problems. Some of the other misconceptions, and their consequences, are listed at

Stop damning by faint praise. Really!

May 24, 2012 4:08 AM ET

Response to Chris Brown
by Martin Holladay

Thanks for the link. Some of the information on the page you linked to is straightforward -- for example: "Sensitivities are not a specific disease entity. ... People with sensitivities react to substances, EMF, temperature, light or other phenomena at levels of exposure that do not seem to affect the majority."

However, the opening paragraph is extremely opaque: "The most common mistake people make is to subject persons with sensitivities to a reverse onus when they report their experience of repeatable, controllable circumstances, contrary to ethics, social convention and laws since the Magna Carta. This practice is unethical in any context, but becomes especially damaging in clinical medicine."

Nov 4, 2012 11:10 AM ET

A difficult path
by Travis Phillips

Having worked on a project for a client with chemical sensitivities, I can appreciate the challenge clients face building a home that doesn't make them sick as well as the difficulty as a builder in being able to successfully meet this goal. Managing a client's expectation is important in any project, but as you've pointed out, it's exponentially more important in this situation.

Also of critical importance is ensuring clients understand that the success of the project hinges on their ability to communicate what their sensitivities are be engaged and responsive during product selection. Since two individuals rarely share the exact same sensitivity, it is impossible for a builder to meet the client's needs without the client's participation. A good partnership can create an outstanding team and a project that the client will appreciate for life; a partnership that isn't as strong can quickly devolve into an adversarial, finger-pointing relationship.

As a side note, kudos to the product manufacturers who provide complete and explicit detail in their MSDS sheets and other product info. The amount of detail in these documents makes all the difference for builders and clients looking to avoid certain chemicals, but it's astonishing how difficult it can be to get this detail from some manufacturers, even of supposed "green" products.

Nov 4, 2012 11:38 AM ET

Response to Travis Phillips
by Martin Holladay

Thanks for sharing tips based on your experience on this type of project. Such feedback is helpful to any designer or builder considering a project involving clients with chemical sensitivity.

Register for a free account and join the conversation

Get a free account and join the conversation!
Become a GBA PRO!