The role of Disinfection/Sanitization/Sterilization in the Laboratory Animal Facility By Belinda Buehl This workforce solution was funded by a grant awarded under the President’s Community-Based Job Training Grants as implemented by the U.S. Department of Labor’s Employment and Training Administration.  The solution was created by the grantee and does not necessarily reflect the official position of the U.S. Department of Labor.  The Department of Labor makes no guarantees, warranties, or assurances of any kind, express or implied, with respect to such information, including any information on linked sites and including, but not limited to, accuracy of the information or its completeness, timeliness, usefulness, adequacy, continued availability, or ownership.  This solution is copyrighted by the institution that created it.  Internal use by an organization and/or personal use by an individual for non-commercial purposes is permissible.  All other uses require the prior authorization of the copyright owner.

Why is it important? Integrity of the research project Colony health Employee health Required by rules and regs from AALAS and “The Guide” Reduces biohazards

What is the difference? Disinfection: Reduction of the # of pathogenic microorganisms on an object to harmless levels. Sanitization: Reduction of the # of microorganisms on a object to a level acceptable for public health standards. Sterilization: Destruction of all organisms on an object. -cidal: kills -static: inhibits

Methods you might use Autoclave Gas sterilization Chemical Radiation Other

Autoclave Uses steam under pressure Length of time dependent on # of items sterilized, minimum is 15 min @ 250°F(121°C) at 15 psi Large and small models available depending on use

Positives and Negatives of Autoclaving Inexpensive Reliable No use of toxic chemicals Negatives Can be corrosive Many objects cannot withstand autoclaving Use of high temperatures and pressure can be dangerous Items must be wrapped in appropriate materials and the autoclave must not be overloaded or steam won’t penetrate objects

Gas Sterilization Uses ETO (Ethylene oxide gas) Kills all known viruses, bacteria, & fungi (even bacterial spores)

Positives and Negatives of ETO Gas Sterilization Good for instruments that cannot be steam sterilized Effective against bacterial spores Negatives Special equipment is required Gas is colorless, toxic, and very flammable Materials to be sterilized must be dry, and well aerated once sterilization is done Explosive!

Chemical Sterilization Most commonly used for surgical instruments Cidex (glutaraldehyde) is most common Requires 3 hours or more of exposure time Bactericidal, fungicidal, viricidal, and sporicidal Can be used for other surfaces

Formalin/Formaldehyde Often used to sterilize rooms Used in a “bomb” form: formalin soln or crystals are heated & allowed to dissipate throughout the room Toxic, carcinogenic, corrosive: i.e. DANGEROUS Rooms must be free of any metal material or organic debris Rooms must also be sealed completely and not entered for at least 24 hours. Limited penetrability

Chemicals for disinfection Phenols Alcohols Halides Aldehydes

Phenols 1st used in clinical practice Phenol itself is corrosive and toxic Chlorhexidine is a phenol derivative common in the lab animal field Can be used as a skin disinfectant

Alcohols Methanol, ethanol, isopropanol Works by dehydrating cells, coagulating proteins, and disrupting cell membranes 70% aqueous solution is more effective than full strength

Halides Chlorine and Iodine Powerful oxidising agents Rapidly become inactive in the presence of organic material Sodium hypochlorite (bleach) and Povidone iodine are common preparations

Aldehydes Denature proteins Glutaraldehyde and formaldehyde (also used for sterilization) Become inactivated in the presence of organic matter

Methods of disinfection, etc used by the lab animal tech All of the above mentioned could be a method used There are many methods to prevent spread of disease such as: Disinfecting foot baths Dedicated mops, brooms, buckets to animal rooms Following strict guidelines on how often rooms, cages, etc are to be cleaned Wash hands often!!!!

Personal Protective Equipment Very important to think about when using the methods described Some forms of PPE would be heatproof mitts, masks, goggles, gloves, rubber boots, coveralls, face shields, respirators, and more

Guidelines Always follow guidelines on the instruments or chemical containers Know where the MSDS sheets are located (Material Safety Data Sheets) Never dilute chemicals more than required as they may not be as effective Likewise, don’t use a soln. that is too concentrated, it could be harmful to you and the animals Follow the rules set forth by The Guide for the Care and Use of Laboratory Animals and by AALAS. Have SOP’s (Standard Operating Procedures) written up and located in binders for reference. If you have questions, ASK!!!!!!!

Where could you work as a Lab Animal Tech? You’d be surprised! University campuses Pharmaceutical companies Wildlife facilities Governmental agencies (state and federal) Private corporations Pet food companies And many more!!!

A little about me BS in Wildlife Management and Conservation Biology Associate Degree as a Veterinary Technician and Laboratory Animal Technician Worked at the following facilities: Department of Agriculture, Trade, and Consumer Protection Dane County Humane Society DNR Bureau of Wildlife Management National Wildlife Health Center Deer-Grove Veterinary Clinic MATC Covance UW Madison – Veterinary Medicine Teaching Hospital

Animals I have worked with as a Lab Animal Tech

Any Questions????