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Hidden Toxins in the Home

“One lesson I’ve learned in my 27 years in this business,” says Bill Dolch, “is that most people are unaware of the toxins they’re exposed to in their own homes.” Mr. Dolch is the owner of Certified Indoor Air, Inc., a company providing comprehensive mold testing and air quality inspections in the Greater Triangle area.

inspecting an HVAC unit

“Although the EPA estimates that 25-50 percent of all buildings in the U.S. are water-damaged, and likely contaminated with mold, people don’t often realize that their homes may be unhealthy. That’s because indoor pollutants are often hidden.

“But, even if you can’t see it, that doesn’t mean you don’t have it. Mold is likely to be found—and to thrive—behind walls, in basements and crawlspaces, or ventilation ducts. The toxins produced by molds and other microbes are spread through the home ventilation system, posing an invisible but serious health hazard.” 

Warning Signs

“Most often, people become aware of a mold problem when it makes them sick,” he says. “A very serious condition—CIRS (see box)—is caused by mold; but indoor toxins can also produce less obvious health problems.

“For example, we’ve found that people will have mild, chronic problems nagging them for years, but it’s a vacation that lets them know they have a toxic house. Many a client has said to me: I wasn’t sure I had a problem, but we went on vacation and felt fine—until we came home!”

Symptoms of CIRS

“Chronic Inflammatory Re-sponse Syndrome (CIRS),” explains Mr. Dolch, “is a condition with a wide range of symptoms that are triggered by exposure to biotoxins— typically mold. The ongoing in-flammation can affect virtually any organ system of the body and, if left untreated, becomes debilitating.

“Symptoms of CIRS are among the most useful signals that a home may be contaminated. So, if you or someone you live with experiences eight or more of these symptoms, get them checked out for CIRS.”

  • Fatigue
  • Pain (increased, unusual), electrical sensation, tingling, numbness, tremors, tics, dizziness, atypical seizures
  • Problems with memory, focus, concentration, finding words, confusion, disorientation
  • Mood swings, loss of interest in activities, depression, anxiety
  • Headaches, light sensitivity, blurred vision, red, teary eyes
  • Sinus symptoms, metallic taste
  • Cough, shortness of breath, asthma
  • Abdominal pain, diarrhea
  • Frequent urination, excessive thirst, temperature regulation problems, appetite swings
  • Weakness, joint aches, morning stiffness, muscle cramps, muscle aches
  • Skin sensitivity, sweats, static electricity/shocks

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Reaction to indoor pollution varies. “Inhalation of microbial antigens can cause a wide range of physical problems, depending on individual sensitivities and health issues.” Mr. Dolch says. “For three-quarters of the population, indoor pollution may not be a significant issue; but one out of every four people carries at least one type of gene that reduces the body’s ability to eradicate mold spores, fragments, toxins, or volatile organic compounds (VOCs). For those individuals, living or working in a moldy building can make them very sick.”

Detective Work

A comprehensive home assess-ment is focused, detailed detective work, notes Mr. Dolch. “For example, one of the tricky aspects of our work is that not everybody reacts the same way to toxins. Sometimes, I’ll go into a home with three kids and only one of them is reacting.

“And contaminants can be hard to find. It’s common to find mold growth in basements and crawl spaces—areas that are damp. But sometimes the location is surprising. In one recent case, there weren’t any visible signs of moisture damage or mold. But when we pulled off the dry wall, we found mold growth inside the insulation.

“I have to listen closely to my clients,” explains Mr. Dolch. “We need to learn about symptoms and health issues they’re experiencing. That information tells us a lot about the potential contamination we should be testing for.”

Comprehensive Assessments

Home assessments, says Mr. Dolch are extremely detailed and thorough. “They have to be, if we are to find the source of an airborne toxin. Our inspections involve careful examination of both the exterior and interior of a home as well as searching for signs of water infiltration, past and present water damage, and mold growth.” 

And, he notes, “attention to detail is especially important during this step because there may be signs of water damage that are not visible. Our list is a long one: we inspect attics, crawl spaces, ductwork, HVAC units, under sinks, behind appliances, and anywhere that water may have caused damage.  Infrared thermal imaging is a valuable tool in this process.”

A good assessment, says Mr. Dolch, includes a thorough understanding of the HVAC system and how it works, and of the pathways by which mold spores are spread throughout the home. As a part of that process, he says, they collect samples of dust to be analyzed for bacteria and specific species of mold.

“We’re also looking for potential as well as current problems,” he adds. “For example, we examine the outer shell of the home—windows, siding, gutters, and downspout systems—for structural issues that may invite water damage in the future.”

Although 90 percent of Certified Indoor Air’s work is mold related, they also test for organic compounds in the air. These can come from cleaning supplies or off-gassing from different kinds of building materials or furniture. “In addition to mold,” Mr. Dolch explains, “many people are sensitive to chemical odors or may react to bacteria, which can harbor in the dust inside the home and circulate through the HVAC system.”

Types of Mold

“A number of molds are considered toxic to human beings,” says Mr. Dolch. “It’s impossible to identify most of these by appear-ance alone, which is why proper inspection, testing, and identi-fication is so important.”

Two of the most dangerous molds are Stachybotrys—also referred to as “black mold”–and Chaetomium. Other toxin producing molds include Fusarium and Penicillium.

Two of the most common molds found in this region, says Mr. Dolch, are Aspergillus and Clado-sporium. “When I find these, I’m not alarmed, but when I found them in high quantities and densi-ty, then we do have problems.”

The outcome of the assessment is a detailed report on findings, including surface and air samples
as well as recommendations for remediation. “We don’t do the remediation,” he explains, “but we provide all the information needed to ensure that problems can be remedied.”

When to Test

“Although routine testing for household toxins isn’t necessary,” says Mr. Dolch, “there are a several instances when it makes sense to get an inspection. First and foremost: listen to your body. If you notice a difference in how you feel when you’re in the house compared to when you’re not, that’s a critical cue.”

Other cues invite further investigation. “Pay attention to any water event that occurs, even if you think it’s minor. It’s important that building materials dry out within 24 hours,” he explains. “If they don’t, there’s potential for serious problems. And certain types of water damage, as from sewage, are also dangerous.”