WHY DOES BACTERIA AND MOLD PRODUCE BAD ODORS

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Q: I am finding that some of my water jobs quickly get a musty odor, much like a moldy smell, even when I arrive the same day the loss occurs. Why can I smell mold that quickly?

 

A: Actually, mold growth does not begin to become microscopically detectable until eight to 10 days after the water incursion, and is not visible until 18 to 20 days.

 

For more information on this, before we get into this particular discussion about the cause of some of these odors you are encountering, please see the article in the May issue of Cleanfax magazine for the peer reviewed scientific documentation.

 

As a water damage technician, we show up at a water job and there is that tell-tale musty, moldy odor. We may even start the drying process when there is no odor, and the next day that musty odor has appeared.

 

What is causing this odor? If the odor is not caused by mold, then what is causing it? The answer is probably bacteria.

 

It is true that the odor could be from old mold. Assuming a normal response time to a water loss of 12 to 24 hours, then for the odor to be coming from mold would mean that the mold was already there before the water loss — thus a pre-existing condition. So if mold is not visible, the source of the odor is probably bacteria.

 

Bacteria basics

 

Before getting into what to do about the bacteria that is causing the odor at the water loss, we need to understand what bacteria are, and if they pose a health hazard.

 

According to paleontologists, who are scientists that study the history of life on Earth, bacteria were the first life form to develop on Earth.

 

Bacteria have the largest numbers of any life form on earth. It is estimated that there are 5 x 10 to the 30th power of bacteria on Earth (this number is a 5 followed by 30 zeros).(1)

 

The microbiologists who study bacteria estimate that there are 10,000,000 species on earth, with only about 9,000 having been identified. In comparison, there are about 5,500 identified species of mammals on earth.

 

Bacteria live everywhere on Earth, and live on everything on earth. Actually "cataloging" all bacterial life will probably never be accomplished. If you went into your back yard and took a shovel of dirt, in that shovel would be an estimated 2.2 million bacteria.(1)

 

Looking at bacteria from a different perspective, a weight perspective, here are some interesting statistics:

 

There are about 6.8 billion humans on Earth, and if each human weighs an estimated 160 pounds, then the total weight of the human population on earth would be about 1.1 x 1012 pounds, this 1.1 x 10 to the 12th pounds. As an example of how big this number is, if we stacked one dollar bills on top of each other, this amount of 1.1 x 1012 of dollar bills would reach the moon, which is about 240,000 miles from Earth.

The total weight of bacteria on Earth is estimated to weigh 1 x 10 to the 15th pounds.(1)

Thus the total weight of bacteria on Earth is much larger than the weight of all the humans on Earth.

Bacteria have always been here and have always been very abundant.

 

When most of us hear the word bacteria, we have an immediate negative reaction. The word "bacteria" to most of us means sickness, illness and disease, among others. Nothing could be further from the truth. If it was not for bacteria, the human race would not exist. Bacteria are 100 percent essential for us, as humans, to live. A few examples:

 

Bacteria on your skin (2)

1,000 different species

Different species live on different regions of the human body

Many act as defense mechanism against pathogenic bacteria

Bacteria in your mouth (3)

500 to 1,000 different species

Even after brushing and rising with mouthwash, thus killing most bacteria, the bacteria regenerate in about two hours (which is a good thing)

These bacteria are a major bodily defense mechanism

Bacteria in your large intestine (4)

700 different species of bacteria, weighing about 4 pounds

Produce vitamin K, vitamin B, thiamine, riboflavin

Digest fiber.

Bad bacteria

 

While there are thousands of bacteria which live on us, in us, and protect us, there are some "bad" ones.

 

There are hundreds of species of bacteria that can, and do, cause sickness and disease. These are called pathogenic. The ones we hear about most often are the likes of Escherichia coli (E-coli), Salmonella, Shigella, Streptococcus, pneumonia, tuberculosis, cholera, etc.

 

And, we have just seen an apparently new bacteria strain of E-coli in Europe.

 

In most buildings, the common types of bacteria that are present include micrococcus, staphylococcus and bacillus. All of these live on our human skin and are mostly benign.

 

The reason these bacteria are found in buildings is that we, as humans, shed our surface layer of skin and these bacteria are also shed with the dead skin cells. So, while there can be pathogenic bacteria in buildings, they are normally not present.

 

While pathogenic bacteria are cause for concern, they can be destroyed by the proper use of biocides/antimicrobials, or by taking away one of their requirements for life, either their food source or water.

 

Bacteria growth

 

Bacteria are single-celled forms of life that are very small in size, about 0.2 to 1 micrometers in diameter. As a comparison, a human hair is 40 micrometers to 120 micrometers in diameter and photo copy paper is about 100 micrometers.

 

Bacteria reproduce by a process that is called binary fission, which means they split from one cell into two cells. Many species of bacteria can reproduce almost continually.

 

The "splitting" can occur as fast as every 15 minutes, which is much quicker than mold reproduces. While this does not seem very quick, watch the math: (5)

 

Start with one cell, 15 minutes = 2 cells, 30 minutes = 4 cells, 45 minutes = 8 cells, 60 minutes = 16 cells

Four hours after the start = 65,536 cells

Eight hours after the start = 4,294,967,296 cells, almost 4.3 billion cells.

With this reproduction rate, the quantity of bacteria literally explodes. Even if we respond to the water loss eight hours after the event, we are caught behind the curve.

 

The numbers go beyond imagination if you look at 24 hours, since the quantity can keep doubling every 15 minutes.

 

With bacterial growth rates that are exploding at a water loss, they have to obtain energy to survive, grow and continue their reproduction.

 

Bacteria obtain energy from digestion. Bacteria's digestion occurs outside of the organism and one of the by-products of this process is off-gassing, which creates the musty odor that we probably smell at the routine water loss.

 

The odor that becomes noticeable at a water loss can be very similar to odor given by mold. These odors are known as microbiological volatile organic compounds (MVOCs). It is this off-gassing that could be the odor that is present when we arrive and/or could be the odor that appears on day two of the water loss.

 

Many times, you will hear water damage technicians say something like, "I am applying a biocide to stop the odor from showing up on day two."

 

What the technician is, in effect, doing is applying a biocide to kill the bacteria which eliminates the generation of MVOCs.

 

Fighting the bacteria

 

The ways to minimize, reduce or eliminate bacteria are by proper cleaning, drying and the application of biocides.

 

There are many different formulations of effective biocides that are routinely used to kill bacteria on a water loss. Many of these solutions use, as their primary "killing" chemicals, the same chemicals that we find in everyday life. Here are some examples:

 

Hydrogen peroxide used on cuts to kill bacteria

Phenols, which are used in biocides, are also the same used in a popular mouth wash

The orange colored biocide that is used by phlebotomists on your arm before taking blood is iodine, which is known as an iodophor in chemical terms

Quaternary ammonium compounds are used in household cleaners/disinfectants that are used in bathrooms and kitchens

Hypo-chlorites that are in solutions are also used in your clothes washer to clean whites, commonly called bleach.

While there is justifiable concern about misuse of biocides, most of the biocides used in our industry have been around for years and when used properly can kill both bacteria and mold and do not pose a human health risk.

 

"Killing" mold is not an acceptable method of mold remediation, but that is for another article. Killing bacteria with biocides is a very acceptable method of decontamination. It is routinely done in hospitals, doctors/dentists offices, food process facilities, restaurants, etc.

 

Bacteria, like all forms of life on Earth, needs water to live. Below is a table showing different levels of water activity and the type of microbial life each level supports.

 

Water activity is the water that is available to support microbial life at the very surface level of a material, which is the location where we find microbial growth.

 

Water activity and moisture content are somewhat related, but a full discussion is for another article.

 

Water Activity (wetness) - Minimum to support                Life Form Supported

0.95        Bacteria

0.88        Most Fungi

0.66 to 0.70         Mold: Penicillium, Aspergillus

As can be seen from this chart, bacteria need a lot of water to live. In fact, bacteria needs more water to live than does mold. As a comparison, the average human should consume 25 ounces of water per day. Less than this amount may lead to health problems. With water activity, if the amount of water is below the above values, then there is not enough water for microbial life to live.

 

When water is taken away from bacteria, they die; some types of bacteria will generate spores as the living bacteria die. This is different from mold. When water is taken away from mold, mold goes into a state called dormancy. Mold, in effect, goes into a waiting pattern for water to return — it does not die.

 

Thus, drying can be an effective bacterial killing method.

 

Musty odors

 

Back to our tell-tale odor at the water loss. That musty odor can be a sign of mold growth, which may not be visible. Mold can be living and growing inside wall cavities, under cabinets, under carpet/pad and in other "hidden" locations.

 

However, the odor you encounter is more likely caused by bacteria that are ever-present in homes and grow very rapidly when exposed to water.

 

If you find mold right after a water loss, it is most likely pre-existing, and not from the immediate water loss.

 

The best method to reduce bacteria and their odors and potential negative health impacts is by:

 

Properly cleaning the affected areas

Drying the structure

Appropriate use of biocides.

If a structure is clean and dry, then there cannot be any microbial life.

 

References:

 

(1)          Whitman, W. B., Coleman, D. C., Wiebe, W. J. "Prokaryotes:

      The unseen majority." National academy of Sciences, pp 6578

      – 6583. June 1998, University of Georgia, Athens, GA

 

(2)          Todar K. Normal Bacterial Flora of Humans Todar's Online

      Textbook of Bacteriology

 

(3)          Zimmer, Carl. "How Microbes Define and Defend Us." Science,

      New York Times. 12 July 2010

 

(4)          Maton, Anthea; Jean Hopkins, Charles William McLaughlin, Susan

      Johnsons, Maryanna Quon Warner, David LaHart, Jill D. Wright

      (1993). Human Biology and Health. Englewood Cliffs, New Jersey,

      USA: Prentice Hall

 

(5)          Zwietering M H, Jongenburger I, Rombouts F M, van 'T Riet K

      (1990). "Modeling of the Bacterial Growth Curve". Applied and

      Environmental Microbiology 56 (6): 1875–1881

 

Richard Driscoll has a B.S. degree in mechanical engineering from Clarkson College of Technology, an MBA from the University of Dayton and is currently working on his doctorate. He is a professor at Webster University, where he provides graduate and under-graduate level lectures on marketing, international business management and business metrics. He is an Institute of Inspection, Cleaning and Restoration Certification (IICRC) Certified Master Restorer and an approved instructor. Driscoll has been consulted by state governments on legislation related to the cleaning and restoration industry. He also is the author and instructor for Restoration Sciences Academy's MR-110 and MR-210 microbial remediation classes. He can be reached at Richard@mayhemmishaps.com.

 

 

SEE WHAT YOU CAN DO WITH AN ORANGE

See the link below , it is great !!
http://www.youtube.com/watch?v=vZp_q_7IExA&feature=fvwrel

can also make a nice candle.

WHY CHEMISTRY ??

Why I am a chemist

By Ashutosh Jogalekar | July 16, 2012| 8

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The iconic double helix; both Watson and Crick needed to learn chemistry to decipher its structure (Image: Jerome Lejeune)

The twentieth century was supposedly the century of physics and the twenty-first century is that of biology. Where does chemistry fit in? The answer is, in both. Chemistry was integral to both the physics and biology that dominate their respective centuries. It has played a major role in human existence for as long as civilization has existed. And it continues to be a central part of much of scientific progress. The reason why chemistry does not seem to conspicuously make its way into the lexicon of cartographers of science is the same reason why the people who do the lights, costumes, event management, casting, musical score, special effects and cinematography for a major motion picture don’t figure on most people’s radar. That’s because their work is so ubiquitous and subtly pervasive that we take it for granted. And often enough chemistry surprises us by stepping into the shoes of the director, actors and writers.
Chemistry is a many splendored thing
I am a chemist. I am passionate about chemistry because of its central and tremendously diverse role in the entire scientific enterprise. Chemists can be doctors, inventing drugs and materials for medical implants. Chemists can be architects, designing materials that can confer resilience, strength and aesthetic shapes to building materials. Chemists can be physicists, calculating structures of molecules using quantum mechanics and shining lasers on them to interrogate their properties. Chemists can be astronomers, literally studying star stuff. Chemists can be climate and energy scientists, studying the impact of climate change on the carbon cycle and developing new materials for solar capture. Chemists can be biologists, probing the fundamental basis of life and its origins. Chemists can be chefs and perfumers, concocting uncanny approximations of natural fragrances and flavors for haute cuisine. Chemists can even be fashion designers, developing novel textiles and colors for the latest season. And chemists can be engineers in a very fundamental sense, building molecules atom by atom.

There are chemists and there are chemists

Molecular model of a metal-organic framework (MOF) designed to capture hydrogen, just one part of a virtually unbounded universe of materials chemists can make (Image: Science Buzz)

Images of chemists inevitably conjure up slightly bug-eyed scientists with unkempt hair holding green frothing liquids. But as with some other portrayals of scientists in popular sources, this image is simplistic at best and a caricature at worst. Reality is more diverse. How would the scene look like if you collected chemists from all specialties, put them together in a room and asked them to practice their trade? Many chemists would appear in front of fume hoods, specialized enclosures that are designed to suck out noxious fumes and allow a chemist to organize his or her wherewithal. You would indeed see some of them holding colorful, bubbling liquids – and this visual aspect certainly contributes to the allure of chemistry – but you would see many others holding tiny vials with colorless liquids or solids. The contents of those vials could range from DNA to snail toxins to new materials for solar energy. You could also see chemists experimenting with lasers, electronics, x-ray machines and spectrometers and they would still be doing chemistry. Tucked away in a corner, you would then improbably find a few chemists wearing neither lab coats nor tinkering with any kind of chemical apparatus. Instead – and this happens to be my trade – they would be intently staring at a computer screen, watching and manipulating 3D images of small molecules and proteins, writing code and running calculations on the structure and properties of these molecules. These people are still doing chemistry. Finally, there’s a small but significant group of chemists who you would not locate in this room; you would find them instead scattered thousands of miles away in rainforests, oceans and the arctic expanse. These chemists are digging deep into the soil, studying amphibians and scooping water in search of new drugs. Others would be testing water, soil and air samples for environmental pollutants.
Chemistry permeates our world
The foregoing discussion exemplifies the sheer diversity of chemical science and its practitioners. The heart of chemistry is the science and art of synthesis, a process that can make novel molecules which never existed before. The impact of this activity on human civilization is hard to overstate. Look around you. Every single bit of material entity that you see has either been synthesized in the flask of a chemist or is a natural compound that has been modified in the flask of a chemist. Even if it is not synthetic, it has probably undergone some kind of synthetic modification that has improved its color, flavor, smell, toughness, flexibility, softness, durability, conductivity, or aesthetic looks. Much of the modern world as we know it in the form of metals, plastics, fibers, drugs, detergents, pesticides, fuels, medical implants, food and drink is the direct result of chemistry. Pondering just one of chemistry’s myriad creations like jet fuel or PVC or aspirin should convince us of its all-pervasive role in human civilization. It would not be a stretch to say that chemistry’s influence on our modern way of life and the rise and fall of nations is equal to that of the development of the calculus.

The poppy plant; a single molecule - morphine - has contributed to its endless allure and geopolitical consequences (Image: Agrofuels)

Saying that chemistry has been influential in the rise and fall of nations is not an exaggeration. There is no other science whose basic entities have had such an impact on international and domestic geopolitics on an individual basis. Time and time again, single molecules have dictated the fate of nations. The central role of iron, bronze and aluminum in the shaping of ancient and modern cultures is well-documented but there’s more. For many years and even now, the economic strength of a country has been judged by its production of sulfuric acid. Or consider morphine, that singular substance which is alluring and forbidden in equal parts. Morphine was responsible for the Opium Wars, a set of conflicts whose repercussions forever changed the geopolitical landscape and future of China. And in a classic case of very slightly altered chemical identity which we will often explore on this blog, morphine’s cousin heroin continues to hold enormous sway on political calculations through the drug trade, leading to entire communities destroyed and billions of dollars spent. The pattern repeats throughout history; indigo, saltpeter, crude oil, rare earth metals, uranium, ambergris, gold, turmeric, silk, salt, all of them substances prized for the presence of one or a handful of molecules, sometimes prized enough to have encouraged trade, caused wars, brokered peace, killed millions, driven men to wealth, madness and despair.
The human science

The development of penicillin is the quintessential example of the intense positive impact chemistry has on our lives (Image: Kenneth Todar)

As I noted in a past post, it’s this intimate connection of chemistry with our world and history that makes it, more than any other discipline, the human science. This has led to a complicated relationship between molecules and our collective consciousness. It is not uncommon for the media to try to steer us clear of the dangers of “chemicals”. What’s usually missing is the context. Sometimes the belief that all chemicals are bad leads to nonsensical advertising, such as the enthusiastic marketing of products that apparently contain no “chemicals”, a practical impossibility if chemicals are defined as molecules of one kind or another. One of the common refrains of those battling this chemophobia is that “the dose makes the poison”, a universal principle that applies to everything from water to botulism toxin. Many well-intentioned studies which seek to warn the public of the dangers of chemicals ignore this basic fact and often miss details of exact doses, statistical significance and sample sizes.
Nonetheless, much of this chemophobia reflects the complicated relationship between humans and science that we have always lived with. In this sense chemistry presents us with a microcosm of the tussle between technological progress and its moral dilemmas; after all, while penicillin brings a person back from the brink of death, nobody can deny that it was also used to kill during World War 1, and it is true that wrong doses of chemicals in the wrong hands can cause much death and suffering. Seen this way chemicals are no different from human beings where the specific context can turn a saint into a sinner. But these facts present us with a challenge that’s no different from that presented by the progression of science and technology since the industrial revolution. Remembering Joseph Rotblat’s words that much of human suffering is related to the time lag between technological developments and our moral and human capacity to fully comprehend them, for better or worse we will continue to be confronted with chemicals, with fossil fuels, with radioactivity and with genetic engineering. In many of these cases however, it is hard to deny that their sum total has greatly contributed to economic and technological progress and has objectively alleviated suffering, at least in some cases like drug development and poverty eradication.
Chemistry@TheCuriousWavefunction
On this blog I will be discussing the nature of chemical science. I will be talking about the history of chemistry and will try to illustrate the incalculable impact that molecules have had on our way of life. Papers will be discussed and the power of basic chemical concepts will be illustrated. Along the way we will meet some of the giants of chemistry on whose shoulders we all stand. Another goal is to discuss the unique philosophy of chemistry, something that has traditionally been neglected by philosophers of science. The overall aim is to point out the central place that chemistry has in our world and to demonstrate that it is very much the human science.
This blog picks up the baton from my old blog with the same name which I have been writing for slightly more than eight years now. That blog has been an immensely rewarding endeavor and has been enriched with comments and criticism by readers, many of whom have paid more attention to it than it deserved. Here I will also be dwelling on my other interest, the history and philosophy of science as well as miscellaneous scientific topics that I am interested in. I am thankful to the organizers of the Scientific American blog network (especially Bora Zivkovic) for this opportunity and am very happy to be joining a first-rate group of bloggers who between them seem to cover almost every field of human inquiry. I hope I can make my own modest contribution to the sparkling dialogue that defines this site, and I greatly welcome and appreciate comments and criticism.