



Friday, July 27, 2012

Disinfectant Chemistry Report Card #6 – Alcohol – Should consumption as a beverage be it’s only use?

Molecular alcohol was fist isolated and discovered by an Iranian scientist, Al-Razi, in the late 800’s. In everyday speaking, alcohol is often referred to ethanol, which is found in alcoholic beverages. Rubbing alcohols are often a solution of 70% isopropyl alcohol in 30% water, which are used in industrial and healthcare applications as surface disinfectants and hand wash sanitizers.

Alcohols are generally volatile and evaporate easily in open air. The oxidative reactivity of alcohols, more commonly referred to as combustibility, is high regardless of their molecular structure, thus making alcohols to be highly flammable and unsafe to be used near heat sources and sparking devices. Health effects of alcohols are also severe, depending on the type of alcohol a person is exposed to. Ethyl alcohol (in alcoholic beverages) is the safest type even if it is known to cause intoxication in high doses while other types of alcohol can cause serious health effects.  In general, most alcohols are classified as volatile organic compounds which are agents known to cause concerns with respect to air quality and if released into the environment in large quantities can cause environmental and aquatic toxicity. 

The exact method of action for alcohols’ efficacy is unknown; however there are three general mechanisms that are believed to be responsible for alcohols’ germicidal actions: 1) Protein denaturation (in simple terms, a change in structure like how boiled eggs become hard when cooked), 2) Lytic action (destruction of cells), 3) Interference with cellular metabolism (affect the ability of cells to perform the functions necessary to survive). Alcohols are known to be both bactericidal and bacteriostatic; for example ethanol is bacteriostatic at 10%, but it is required to be at least 30%-40% to act as bactericide. Alcohols can also inactivate fungi, mycobacteria, and viruses with less activity towards non-enveloped viruses.  They are however ineffective against bacterial endospores In fact, spores can survive in high concentrations of alcohols for years.  One of the main disadvantages of alcohols is their fast evaporation rate and the fact that they do not remain long enough on the surface to sufficiently inactivate pathogenic microorganisms. Ethanol and isopropanol at 60-80% take about 1 to 5 min to disinfect as per standard disinfection test methods; however they dry on the surface in less than 20-30 seconds. Shorter exposure (usually < 30 seconds) of pathogens to alcohols would often result in incomplete germicidal activity. Below a few often-used short chain alcohols and their antiseptic properties:

     Methyl Alcohol: Also known as methanol is considered to have the least antimicrobial activity and is therefore the least used. Methyl alcohol also opposes high toxicity levels to humans due to its neural damaging properties.

     Ethyl Alcohol: Also known as ethanol is mostly effective against live vegetative bacteria.  Presence of 30 to 40 percent water is a key to ethanol’s germicidal activity.

     Isopropyl Alcohol: Also known as isopropanol, is the isomeric form of propanol that is often used for surface disinfection. Propanols (three-carbon alcohols) are the largest alcohol molecules that can be dissolved in water in any ratio. Having a larger molecular weight than ethanols, propanol and isopropanol have faster/higher germicidal activity than ethanol, however twice as toxic to humans.

Here’s how we would score alcohol on the key decision making criteria:


     Speed of Disinfection – B to C

o     Contact times range from minutes to hours depending on the concentration, type of alcohol used and organism to be inactivated
o     Due to the ready evaporation of alcohol, contact times need to achieve disinfection cannot be attained without reapplication

     Spectrum of Kill – B to C

o     Similar to the speed of disinfection, performance in this criteria is tied to the in-use concentration and type of alcohol used

     Cleaning Effectiveness – D

o     Alcohols are not efficient cleaners as they do not have detergency properties, however, some alcohols can dissolve both polar and non-polar substances, like salts and greases

     Safety Profile – C

o     Alcohols are classified as combustible and flammable chemicals that are unsafe to be used near heat sources and sparking devices

     Environmental Profile – B to C

o     In low concentrations they are considered degradable when released to the environment

     Cost Effectiveness – B to C

o     Alcohol is a commodity that is readily available in concentrated formats, however, is generally purchased as a Ready-To-Use Solution

**For more in-depth scientific information about Alcohol and other disinfectant chemistries, stay tuned to www.infectionpreventionresource.com

Bugging Off!


Tuesday, July 17, 2012

Rub-a-Dub-Dub there’s a Rubber Duck in my Tub…..

Summer, a time for eating, drinking and catching up on some reading all of which you often do while on vacation or enjoying a lazy afternoon at the cottage.  With this in mind.....and as many of our Guest Bloggers are, have or will be taking vacation, we thought for the summer months we would change gears and blog about a book we think is worth reading.  While perhaps not topping the charts like "Fifty Shades of Grey", "Slow Death by Rubber Duck: How the Toxic Chemistry of Everyday Life Affects Our Health" by Rick Smith, with Bruce Lourie and Sarah Dopp is an excellent, although at times exasperating book.

The easy-to-digest tone of the book, and the lighthearted title might lead one to misjudge the seriousness of the message, but make no mistake that the core of the book is very serious indeed even to the extent that the researching of it became a real threat to the well being of its author. 

 While taking a pause from the process of stuffing a child's Christmas stocking Smith read the fine print on a package of socks.  The label identified that Triclosan - a broad-spectrum antibacterial agent registered with the US EPA as a pesticide, and linked to human health effects and antibiotic resistance - was a component of the sock fabric.  In fact Triclosan showed up in many of his child's stocking stuffers from rubber ducks to underwear, and the discovery of its ubiquity launched Smith on an unnerving adventure.  After reading this, I took the "Triclosan Challenge" and read through countless product labels in my home.  Much to the chagrin of my husband we no longer use his favorite brand of toothpaste and you will most definitely NOT find any antibacterial soap in the Kenny household.  I don't care how great a sale is on!

 The book describes in detail an experiment in which the author turned himself into a human guinea pig.  Having identified potentially hazardous pesticides, preservatives, and other known toxins (to humans and/or the environment) Smith purchased scores of brand-name products in which these agents appeared and resolved to use the exclusively over a 4-day period. The products included stain removers, shower gel, shaving cream, soap, microwaveable plastic containers, toothpaste, air freshness, canned foods, and more.  Blood and urine samples were taken before the experiment, regularly during, and at its conclusion.  The results were remarkable.  In fact so compelling that like the "Triclosan Challenge", at home we changed the type of canned tuna we eat, we no longer use non-stick cooking pans, and I can say I have probably only had 2 bags of microwave popcorn since reading this book several years ago.

 In the course of the 4-day experiment, Smith's phthalate level, which is believed to cause testicular dysfunction in children, went up by 22%; the amount of BPA in his blood, linked to breast and prostate cancer, climbed 7.5%; and the level of Triclosan shot up by 3,000%!!!  Triclosan is believed to interfere with thyroid function and is not metabolized by the human body or even by the sewage waste process, making it an almost ubiquitous environmental chemical in water.  I wonder what the levels are in the Trent River where I just spent the weekend swimming and bathing in (using Triclosan and phthalate free soaps of course!).

 Two conclusions are reached by Smith and his colleagues.  "What we do in our everyday lives really matters in terms of the level of pollution affecting us". And, "It doesn't seem to matter where you live or what you do for a living; we're all united by pollution."

 Regardless of the conclusions drawn, science is not the villain here.  Science simply responds to the needs and/or wants of society.  In recent years the rapid reduction of toxic and persistent chemicals such as gluteraldehyde, Triclosan, and quaternary ammonium compounds from the healthcare environment, and the explosion of less toxic products or procedures are examples of a scientific response to the desire of the marketplace.  Humans needn't fear science; indeed this is a book of optimism.  To close with the words of the author, "We're very much at a watershed moment.  The scientific evidence of human harm from these chemicals is overwhelming.  It's driving different consumer buying habits and forcing companies to change."

 I hope you'll consider putting “Slow Death by Rubber Duck” on your reading list this summer.  I have to admit, there we're times I had to put it down for fear of scaring myself into living in a bubble, but in the end I think I am a far wiser consumer!

Bugging Off!


Tuesday, July 10, 2012

Mattresses....a soft place on which to lounge, nap or sleep

I've always been lead to believe that mattresses are soft, comfortable surfaces on which to lay my poor weary body.  Sure there are those of you who like PaPa Bear choose the stiff as a board mattress or like MaMa Bear who prefer the super soft pillow top mattress, but I would hazard a guess that most of us are like Goldilocks or Baby Bear and choose something in between.  Regardless of our mattress preference I believe I can say with certainty that you would never lump your mattress into the same category as your countertops, toilets, sinks or tables when it comes to cleaning.  Why then do we do so in hospitals?

I can hear the AH-HA's from here!!!  Many of you are likely saying, why because they are covered in a "plastic" material that is water resistant and surely, a surface that is water resistant must be able to be cleaned and disinfected like a hard surface such as a countertop.  WRONG. 

If you have not seen or read it, there was an abstract presented at the APIC conference in San Antonio by researchers at Xavier University that investigated the cleaning practices for hospital mattresses at the top US adult hospitals.  Using the US News & World Report they contacted the top 113 hospitals by phone asking the same 5 questions: What chemical do you clean your beds with?  How do you mix or dilute the chemical?  How long do you leave the chemical on the bed or do you just let it dry on the bed?  Do you use anything other than the chemical first, like soap and water?  Do you rinse off the cleaner after you clean the bed?

Of the 113 hospitals, 69 agreed to answer the questions.  The chemicals used to clean the mattresses included Quaternary Ammonium Compounds, Bleach Compounds, Phenolic Cleaners and Hydrogen Peroxide.  Only 2 of the hospitals were using products within the recommended pH.  Only 16 were cleaning prior to disinfection and only 6 were rinsing the disinfectant off after use.

This is where last week's blog comes into play.  Read the label, interpret correctly, understand and follow the label instructions found on your disinfectant AND the cleaning and disinfection instructions of the mattress material manufacturer.  Disinfectants are intended for use on hard, non-porous surfaces.  In fact, until May 31st of this year, the EPA did not have an approved product performance test guideline that disinfectants could be tested for efficacy against and make label claims of disinfection of soft surfaces such as mattresses, fabrics or textiles.  Further, if you've taken the time to read the cleaning and disinfection instructions from the manufacturers who make the mattress material found on hospital beds you would have noted that they recommend cleaning the mattress with soap and water, disinfecting the surface, and then rinsing.

My colleagues and I for years have recommended that hospital mattresses be rinsed post disinfection.  We weren't trying to create a make-work project.  We weren't trying to complicate the cleaning and disinfection process for your housekeepers.  We were in fact actually trying to follow and comply with the instructions given by the mattress material manufactures to ensure that the disinfectants being used were used correctly.

I hope you will take the time to review your cleaning and disinfection practices, to read a few labels or cleaning and disinfection instructions and make any necessary changes you need to!

Bugging Off!


Thursday, July 5, 2012

Simon Says.......READ (understand, interpret and follow) THE INSTRUCTIONS!

A few years back, my niece put a popcorn kernel in her ear which required a trip to the ER to have it removed.  While it may not have been voiced, I know we were all thinking the same thing “what on earth possessed her to do that?”  Last week, while walking down the halls at SickKids in Toronto, I came across two shadow boxes of “foreign bodies” that have been removed from either air passages or food passages of children over the years.  I suppose Rachel’s popcorn kernel would have to go in a new category of “foreign bodies removed from auditory passages”, but the same question still hangs in the air “what possesses a child to do that?”  The answer I think is that children often learn by experience or trial and error.

Read and follow instructions. This sounds easy enough. It isn't. For some people, it's the key to most of their academic or workplace problems. They read or hear one set of instructions, but their teacher, supervisor or trainer has given different instructions.  Some people deliberately ignore instructions. They "wing it."  They think they can scrape by, doing any old thing they choose (or in the case of cleaning do it the way their mother taught them).  They're wrong.  It doesn't matter how good a job you do if you do the wrong job.  You're going to get a bad grade (or get fired).

Doing a job well begins with understanding exactly what the job is.  In the case of cleaning and disinfecting it means reading, understanding, interpreting and following the instructions found on the product’s label.  I challenge you to complete the following drill to see how well you follow instructions. 

Directions: Read the entire exercise before doing anything else. Do exactly as instructed. Under no circumstances are you to speak or ask a question.

Name: _______________________________
1.    Read every instruction before you do anything.
2.    Proceed carefully and cautiously.
3.    Write your name in the designated space provided therefore, below the paragraph that starts with the word "Directions".
4.    Circle the word "name" in sentence three.
5.    Draw five small squares in the supper left-hand corner of this page.
6.    Put an "X" in each square.
7.    Put a circle around each square.
8.    Sign your name in the lower right-hand corner of this page.
9.    After your name, write "yes, yes, yes!"
10.   Put a circle around each word in sentence number 8.
11.   Put an X in the lower left-hand corner of this page.
12.   Draw a triangle around the X you put down.
13.   On the reverse side of this page, multiply 703 by 1,850.
14.   Draw a rectangle around the word "page" in sentence number 3.
15.   Snap the fingers of your left hand.
16.   If you think you have followed these directions, write "I have" in the space provided below.
17.   Shut your eyes for just a few seconds.
18.   Please ignore instructions four through seventeen, and follow the instructions in sentence number three, to complete this drill.
(Modified from the original by Prof. Howard R. Lurie, Villanova Law School)

Be honest, how many of you actually read the entire list as directed before starting to answer the questions?   For once, I actually did.  Generally, I’m that person who would have started answering the questions as I went to save time.... I like to be efficient.  I mean, why read through a list when I can just answer as I go!

The same holds true for choosing and using cleaning and disinfectant agents.  We have a preconceived notion that we know how to use them without truly reading and understanding (or following) the label.  We mistakenly assume that the because we use cleaning products on a daily basis we know how to use the products we use at work and we mistakenly believe that if we create infection control programs based on Health Canada or CDC Guidelines that those guidelines are written in such as away to ensure the proper use of cleaning and disinfecting agents.  They’re not.

 Cleaning and disinfecting agents are designed for use on hard, non-porous surfaces.  We will NEVER have one single product that can be used on every single surface.  Do you know what surfaces your product(s) can or cannot be used on?  Do you know if they should or can be applied by spraying or should you avoid spraying and simply wipe the surface with a damp cloth?  Can you let them air dry or do you need to rinse?  Perhaps there are only specific surfaces that need to be rinsed.  Is the product intended to be use on porous surfaces (more on that next week).  Do you need to reapply to ensure disinfection contact times are met?  Do you need to clean with a separate detergent before you can disinfect the surface?  Does your housekeeping, nursing or clinical staff REALLY know and understand how to use the product(s)?   It’s all well and good that they can answer the question of the contact time should an auditor ask them, but knowing the contact time does not imply that they know how to use the product.

 Do your facility policies, procedures and training programs include detailed instructions of how to use the products?  At the very least, do the policies and procedures match the instructions on the product labels or have you blindly created policies based on infection control guidelines without consideration for how the product is truly meant to be used. This leads to the next question, who does the training?  Many facilities pair people up with a more experienced member of the staff.  This does not necessarily mean the training is effective.  Generally the new person learns the bad habits of the trainer – not the most optimal way to ensure a successful Infection Control program.

 I’m happy to say that Rachel who just turned 7, to my knowledge has never again stuffed something into her ear, nose or mouth.  I on the other hand, while cleaning my floors on the weekend reverted to the Glug-Glug method of diluting the product I was using (mixed with hot water I might add) and ended up with streaky floors.  Even I, an “expert” in the use of chemicals don’t always read or follow directions.....

Bugging Off!


Tuesday, July 3, 2012








  • Speed of Disinfection – B to C

  • Spectrum of Kill – A to C

  • Cleaning Effectiveness – D
  • Safety Profile – B to C

  • Environmental Profile – A
    • Ozone degrades into oxygen making it an environmentally preferable disinfectant chemistry
  • Cost Effectiveness – B to C
    • High initial investment for ozone generating equipment
    • Long term investment requires routine maintenance and replace of parts
