After-hour HVAC Shutdown May Dramatically Increases Airborne Mold and Bacteria in Offices

A recent study published in the journal of Indoor and Build Environments found that when building HVAC systems are shut down, airborne bacterial and mold concentrations dramatically increase. The study investigated the relationships between the airborne bacteria levels, mold levels, and thermal environmental parameters, i.e., air temperature and relative humidity, in offices with a Heating Ventilation and Air-Conditioning (HVAC) system operating. A total of 101 samples were collected from two typical air-conditioned office buildings. There was evidence that intermittent operation of the HVAC system may significant influence both indoor airborne bacteria and mold levels. The results showed significantly higher airborne bacteria and mold levels in offices during non-office hours when air-conditioning systems were shut down as compared to offices where HVAC systems were left running during non-office hours. The study shows that the airborne bacteria and mold levels correlated with the thermal environmental parameters, i।e. lack of airflow, increase humidity and ambient heating from the outside environment.

Citation

Wong, L।T., K.W. Mui, P.S. Hui, W.Y. Chan, and A.K.Y. Law. "Thermal Environmental Interference with Airborne Bacteria and Fungi Levels in Air-Conditioned Offices." Indoor and Built Environment". 17.2 (April 2008): 122(6).

Author's Comments

The findings of this study indicates greater research is needed related to HVAC systems and cost saving provisions, such as after hour shutdown. Property managers and plant managers for schools and office buildings should be aware of these findings. Or more importantly they should bring it to the attention of the proper decision makers. When companies or schools try to save money by shutting down the HVAC during after-hours they may not be aware that they may also create indoor air quality problems. This study found that workers are exposed to elevated concentrations of mold and bacteria when HVAC systems are shut down after hours. Healthy workers are more often more productive, take less sick days, and in general, add to a enjoyable workplace. Even though mold has not been directly linked to major illness in healthy individuals, the effects of long term exposure remain unknown. Moreover, individuals allergic to mold and asthmatics will experience likely experience respiratory symptoms. Their symptoms may not be life threatening, but those individuals will likely not feel 100%. Everyone has had a cold from time to time. It's no fun to be working with a stuffy head and sore throat. But we do it and the cold passes. Just imagine if you went to work everyday and had to deal with cold-like symptoms. It wouldn't be much fun.

Indoor Air Fungus Aids in Biofuel Production

The bane of military quartermasters may soon be a boon to biofuels producers. The genome analysis of a champion biomass-degrading fungus has revealed a surprisingly minimal repertoire of genes that it employs to break down plant cell walls, highlighting opportunities for further improvements in enzymes customized for biofuels production. The results were published online May 4 in Nature Biotechnology by a team of government, academic, and industry researchers led by the U.S. Dept. of Energy Joint Genome Institute (DOE JGI) and Los Alamos National Laboratory (LANL).

The discovery of Trichoderma reesei, the target of the published analysis, dates back to World War II, when it was identified as the culprit responsible for the deterioration of fatigues and tents in the South Pacific. This progenitor strain has since yielded variants for broad industrial applications and is known today as an abundant source of enzymes, particularly cellulases and hemicellulases, currently being explored to catalyze the deconstruction of plant cell walls as a first step towards the production of biofuels from lignocellulose.

“The information generated from the genome of T. reesei provides us with a roadmap for accelerating research to optimize fungal strains for reducing the current prohibitively high cost of converting lignocellulose to fermentable sugars,” says Eddy Rubin, DOE JGI Director and one of the paper’s senior authors. “Improved industrial enzyme ‘cocktails’ from T. reseei and other fungi will enable more economical conversion of biomass from such feedstocks as the perennial grasses Miscanthus and switchgrass, wood from fast-growing trees like poplar, agricultural crop residues, and municipal waste, into next-generation biofuels. Through these incremental advances, we hope to eventually supplant the gasoline-dependent transportation sector of our economy with a more carbon-neutral strategy.”

http://www.nature.com/nbt/journal/vaop/ncurrent/abs/nbt1403.html

Fun With Fungi for Teachers and Students.

What you need:
1. A sealable sandwich bag
2. A piece of bread (I used some leftover porkchops, see photo on the right, covered with Pencillium sp.).
3. A paper towel
4. A little soil from outdoors or a potted plant

What you do (Part 1):
1. Place your bread in the bag. Dampen the paper towel and put it in the bag
with the bread and add a pinch of soil. The soil carries a few mold spores.
2. Let some air in the bag and zip it or tie it up so it's securely sealed. Label the
bag with the date and a name for your experiment, say, “Mold Test 1”.
3. Put the bags in a warm, dark place for about three days.
4. Look at the bread with a magnifying glass through the bag. If nothing has
happened after three days, wait three more.
5. Soon you’ll have a mold garden.

Very Important
THROW AWAY BAGS WITHOUT OPENING THEM WHEN FINISHED.
Breathing too much mold can make you sick. In dirt, mold is very spread out.

What’s happening?
Mold is not a kind of plant. Mold is not a kind of animal. Mold is a kind of fungus.
Fungi (FUN-jie) thrive by attaching themselves to a source of food. Famous
fungi include mushrooms, yeasts, mildews, and “athlete’s foot” fungus.
Mold is made up of millions of spores, or tiny microscopic seeds, all growing
together in a colony. Mold comes in a variety of furry, bright-colored blobseverything
from red to bright purple, depending on the type. The fuzzy-looking
spores weigh so little, tiny air currents can carry them through the air. When they
land someplace where the conditions are just right, they grow into new fungi.


Copyright 2001, Bill Nye and Nye Labs, LLC.All rights reserved.

Is Your Home Making You Sick?

NEW YORK (Ivanhoe Broadcast News) -- You may have heard of toxic mold and sick building syndrome. Could your home also make you sick?
The Environmental Protection Agency estimates indoor air quality is two- to five-times more polluted than the air we breathe outside.
"Living in a home that is polluted with mold can cause all sorts of respiratory problems," Neil Schachter, M.D., tells Ivanhoe. That's a great concern to homeowner Scott Lerman, who has a 4-year-old child.
"We want to make sure that our house is as healthy as it can be so that my son can be as healthy as he can be," says Lerman, who agreed to let Dr. Schachter, a lung specialist from Mount Sinai School of Medicine in New York City, inspect his home.
During the inspection, Dr. Schachter found water damage was causing mold to grow in Lerman's shower. He advises the Lermans and anyone with a similar problem to clean moldy showers with chlorinated wipes and avoid spraying any chemicals that might irritate the lungs.
Because dust can also cause respiratory problems like allergies and asthma, Dr. Schachter recommends putting clean area rugs over dusty carpets and getting rid of dust ruffles. He also says not to store items beneath the bed and to be aware that clutter stored in the basement can collect dust. Pollutants can also come from outside, so to keep them out, Dr. Schachter suggests installing a window filter.
"You assume your house is healthy until you get someone to point these things out," says Lerman, who is now committed to eliminating more than just dust in an effort to keep his family healthy.

Clean Up That Moldy Mess

A musty, mildewy smell is the undeniable odor of mold. And it may be lurking in more places than you know -- having harmful effects on your health. Now, we tell you how to track down mold.

Holly Russo's tub comes clean now, but there was once a moldy nightmare lurking underneath it. "Our first reaction, when we saw the mold, was absolute horror. I could not believe what was under there. I've never seen anything like it," says Russo.

Mold that's made its way indoors can cause health problems, but many people still don't understand the hazards. Now, industrial hygienists are growing mold to learn more about how it grows, what it grows on, and how mold makes us sick.

"I want to know what makes up that moldy, musty smell. I want to know are there compounds there that can cause people to have health problems," says Terri Pearce, Ph.D., an industrial hygienist for The Centers for Disease Control's National Institute for Occupational Safety and Health (NIOSH).

In a lab, with the perfect blend of moisture and warmth, mold spores, or tiny cells, grow on different types of building materials. With the right amount of moisture, mold can grow faster, turning an ordinary ceiling tile into moldy messes.

Researchers learn which materials withstand mold better -- and which moldy smells come from mold that may cause more serious health problems. "Some of the chemicals that make up that odor actually are known to be irritants and so they can cause people to have respiratory health affects," explains Dr. Pearce.

Learning more about mold helps researchers develop better ways to find it, treat health problems, like asthma and allergies, and teach how vital it is to clean up moldy messes.

Moving Ahead With Guidelines To Control Indoor Mold Contamination

Amid growing public concern about mold contamination of homes and its associated health effects, a new study is recommending policy approaches for controlling mold in homes that could be used on local and nationwide bases

The study, done by Felicia Wu, Tom Biksey, and Meryl H. Karol compares policies for regulation of mold with those previously developed to regulate two other contaminants in the indoor environment, radon and lead. While federal, state, and local agencies have policies and regulations concerning radon and lead, few state or local policies have been developed for mold and no federal agency has Congressional authority to regulate or develop indoor mold policy, the study points out.

Based on lessons from radon and lead, the researchers recommend policy approaches for controlling indoor mold that rely on building and housing codes, maintenance and rehabilitation regulations, home marketing incentives, and public education on moisture and mold control.

“While it is not yet feasible to develop standards and regulations for acceptable mold levels in the home, guidelines and policies can be developed at the federal, state, and local levels to control moisture and mold in homes,” the report states।

American Chemical Society (2007, July 5). Moving Ahead With Guidelines To Control Indoor Mold Contamination. ScienceDaily.

ERMI and MSQPCR: State-of-the Art DNA Mold Diagnostic for Use in the Science of Building Forensics

Presented Feburary 22, 2008 at the American Academy of Forensic Sciences, Sick Building Symposium. By Edward A. Sobek, Ph.D.

The goal of this presentation is to provide the audience with a set of guidelines to follow to ensure an accurate assessment of fungal contamination when using Mold Specific Quantitative Polymerase Chain Reaction (MSQPCR) and the Environmental Relative Moldiness Index (ERMI), to educate the audience to the many benefits that MSQPCR and ERMI analysis provide over standard assessment methodologies and to inform the audience of the potential pitfalls associated with MSQPCR data interpretation. ERMI and MSQPCR analysis hold the potential of becoming the standard for mold detection in the United States. This presentation will impact the forensic science community by showing the annual medical costs incurred by asthma patients suffering from mold-related symptoms are estimated to cost 3.8 billion dollars annually. Much of the suffering and expense can be foregone, if the focus of treatment shifts from patient treatment to treating the source, which in most cases, can be found in our homes, schools and offices. MSQPCR or mold specific quantitative PCR is a highly accurate and sensitive molecular technique for the detection and quantification of molds. The assay was developed by the U.S. E.P.A. in response to the ever increasing mold problems associated with homes and buildings in the United States. MSQPCR, which is a variation of quantitative PCR, provides the input data from which the ERMI score is derived. The ERMI score is used to determine how a home ranks on a National Scale in terms of mold burden. ERMI, while a relatively new tool, is rapidly gaining a stronghold as the gold-standard for mold detection in homes and building. Herein, several case studies will be reviewed; each serving as a testament to the power of ERMI and MSQPCR in the field of building forensics and indoor air quality. In each study, MSQPCR was used to identify fungal contamination, or lack thereof, in a variety of indoor environments. The ERMI indices derived from MSQPCR data will be presented. Moreover, an in-depth examination of data interpretation will be explored, from laboratory to the final site assessment and recommendation. The winding path called "data interpretation" will be decomposed to, 1) describe the methodologies to ensure an accurate assessment of fungal contamination, 2) highlight the scientific inquiry required to compose a compelling and highly accurate assessment, and 3) determine the level, complexity, and potential health effects, to occupants, exposed to fungal contamination, in the indoor environment.

A little About Me

I have worked in the field of indoor air quality since I graduated with my doctorate in 2002. But I started studying molds much earlier in my career as an undergraduate research student (1990). In all those years I have never lost my fascination with these remarkable creatures. That fascination and experience is what defines my goal as Director of Clean Air Labs.

As a laboratory director, I strive to provide inspectors and their clients with the best possible microbial detection technology available. In addition, I try to provide clients with the means wherewithal to use that technology. Because, in the microbial world, there are all kinds of werewolves, but no silver bullets. I view any technology, no matter how grand, as a tool, and treat it as such. No single technology is ever going to provide all the solutions. Microbes live together in complex and dynamic communities, regardless of habitat. Unlike asbestos or lead, microbial communities are subject to rapid change in relation to environmental condition. Inspectors need to be able to deal with the biological dynamics inherent in microbial communities in order to solve indoor air problems. Hence, an inspector needs many tools in the toolbox. My goal is to provide those tools along with the knowledge to answer the tough biological questions that are so often associated with problems found indoors.

A life goal I have is to educate. I am convinced that our children need to learn science starting in grade school; hence, I founded the IAQ Outreach Program with Clean Air Labs, where I and my staff educate elementary students concerning the importance of healthy indoor environments. A more advanced form of the program allows local high school classes to visit the lab on field trips to have hands-on experience with biotechnology and DNA assays for environmental microbiology.

Specialties:
Educator, DNA-based Mold Investigations, Inventor, Consultant, Product Evaluator, Seminar Speaker, Research Scientist, Fluorescent Microscopy, Microbial Detection Technology

Sick building Syndrome Symposium

The Sick Building Syndrome Symposium held during the American Academy of Forensic Science(AAFS)meeting last week in DC was a overwhelming success. It ran two days and included over 12 speakers. Each day the session filled up. I would estimate that over 200 people showed up over the course of the two days. Talks ranged from standard indoor air investigations for mold and other non-biological particles to the psychology and health effects of poor indoor air quality. I discussed the use of DNA to detect 36 species of mold from settled dust indoors. Below is a list of topics and presenters.

Thursday's Sessions:

Opening Remarks by Session Organizer, Walter E. Goldstein, PhD, MBA, PE

Multidisciplinary Symposium on Sick Building Syndrome.
by David M. Benjamin, PhD

Studies of Building Related Asthma and Respiratory Symptoms in Relation to Dampness and Microbial Contamination of Indoor Environments.
by Jean M. Cox-Ganser, PhD

Psychiatric Issues in Toxic Building Syndrome.
by Joseph N. Kenan, MD and Daniel A. Martell, PhD

Forensic Investigations on Mold Growth in Damp Buildings.
by Philip R. Morey, PhD

Sick Building Syndrome.
by Gary R. Brown, BS

Mold and Moisture Control-EPA Voluntary Guidance.
by Laura Kolb, MPH

The Analysis of Microbial Volatile Organic Chemicals From Mold Using Air Canisters and Gas Chromatography.
by Jack Cochran, BS

Friday's Session (I was the moderator)

Summary of First Half-Day Presentations and Second Half Day Agenda.
by Walter E. Goldstein, PhD, MBA, PE

Sampling for Airborne and Surface-Associated Microorgansims.
Mark Buttner, PhD

A Rapid High Volume Sampler for Trace VOCs Collection in the Field.
by Brian A. Eckenrode, PhD

Analysis of Bioaerosol Samples.
by Patricia Cruz, PhD. Presented by Mark Buttner, PhD

Use of Microscopy in the Sick Building Syndrome Investigations.
by James Millette, PhD

ERMI and MSQPCR: State-of-the-Art DNA Mold Diagnostics for Use in the Science of Building Forensics.
by Edward A. Sobek, PhD

Panel Discussion- Potential Solutions to Sick Building Syndrome Challenges.
Included all Speakers that were present

Indoor Forensics Debut

I'm sure by now that most people are aware that the average American spends nearly 90% of their lives indoors. I'm also sure that you have been bombarded by the media with talk concerning indoor molds, sick building syndrome, allergens, VOCs, lead, etc. I hope to post some interesting facts about indoor air in relation to many of these problems, but instead of the "crazy killer mold", I will take a scientific approach and provide meaningful information to help people take a proactive approach towards ensuring that the air they breath indoors is healthy.

Most home and property owners aren't aware that they can do a lot own their own to minimize the risk associated with indoor air contaminates. These are the types of things I will focus on. I like to do things myself rather than call an inspector who will most likely tell me I have a problem, but leaves me with no solution. I'm not being cheap, I am in the business and know that while there are many good inspectors out there, there are many more who should not ever be allowed in someones home. We homeowners need to take care of our houses as if they are extensions of our bodies. After all, they makeup our environment. A sick house stricken with water leaks, and afflicted with chemicals from particle board, and various household chemicals can and do make people ill. They often aren't aware of it, and will spend a lot of money at the local doctor's office, when all they had to do was clean out their gutters 3-4 times per year.

I will try to do my best get get some good info out to you and hope you will respond with questions and comments that make this blog a great place for educating the public towards a healthy indoor environment.