UNIT 5
Biosafety
What is Biosafety?
Principles and practices employed to protect laboratory personnel and the environment from
exposure or infection while working with living organisms, biological materials, or agents.
- Included are any materials that may be potentially infectious.
- Includes recombinant DNA research
Agents and Risks
The “agent” is the what creates risk.
Risks to the worker or environment are often unknown.
Determining “acceptable risk”?
Assessing Risk
There is always risk!
The risk must be identified
The risk is evaluated
The risk must be measured
Plan to minimize the risk
Who Determines Acceptable Risk?
Assessment is conducted by a Biosafety Professional in partnership with and based on
information provided by the Principal Investigator
The assessment is presented to the Institutional Biosafety Committee (IBC) for approval
Identifying Risk
Understand the biology of the agent
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Susceptibility and transmission within the host
Hazards associated with equipment and procedures
Goal: Provide the highest practical protection and the lowest practical exposure
WHO-World Health Organization
Agents Assigned Risk Groups
RG-1 Unlikely to cause disease in humans or animals
 low individual or community risk
RG-2 May cause disease but typically not serious
 individual risk, low community risk, treatable
RG-3 May cause serious disease, usually treatable
 High individual but low community risk, serious respiratory agents
RG-4 Serious or fatal, often not treatable,
 Easy transmission, high individual and community risk
Biosafety Levels (BSL)
Different than the Risk Groups!!
 Risk groups used in risk assessment
 BSL are used in risk management
BSL are ways to control the agent
 facilities, safety equipment, practices, PPE, etc.
Once risk is assessed then the appropriate BSL is determined
BioSafety Level 1
Well characterized, non-pathogenic organisms or agents
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Open bench- no containment
Use good laboratory practices, waste disposal, and aseptic techniques
Example: E. coli K-12 strains
BioSafety Level 2
Agents of moderate hazard to personnel or environment
Basic lab, but restricted access, containment during certain processes (i.e. aerosols, large
volumes, etc.)
Autoclave and Biological Safety Cabinet desired
Use good laboratory practices, waste disposal, and aseptic techniques
Example: most non-respiratory, non lethal, agents
BioSafety Level 3
Agents of high hazard to personnel or environment
Respiratory exotic or indigenous agents which are easily transmissible causing serious or lethal
disease
All work is contained, engineering controls and controlled environments we currently do not
have the facilities to handle.
Example: Mycobacterium tuberculosis, SARS, etc.
BioSafety Level 4
FORGET ABOUT IT!!!
Hemorrhagic fever, deadly viruses, etc.
Total containment, airtight labs, “submarine” doors, air pumps, water treatment, HEPA
filtration, etc.
Positive pressure “moonsuits”
Laboratory Acquired Infections (LAI)
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Bacterial:
76% from clinical labs
8% from research labs
Exposure:
60% acquired from inhalation
Other exposures include:
digestion, sharps, splashes, direct and indirect contact
Viral
16% from clinical labs
70% from research labs
 32% from animal related activities
Biohazardous/Medical Waste
Waste that is potentially infectious to humans, animals or plants. It includes:
 Medical Waste according to MMWRA
 Regulated Waste by MIOSHA
 Regulated Waste by CDC/NIH
Biohazardous Waste Management Plan
Must outline how generating facility complies with the MMWRA:
Types of wastes generated
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Storage and disposal of wastes
Contingency plans
Training
Biohazardous Waste Categories
Cultures and stocks of infectious agents and associated biologicals
 laboratory waste
 biological production waste
 discarded live and attenuated vaccines
 culture dishes and related materials
 contaminated PPE
Biohazardous Waste Categories
Liquid human and animal waste
liquid or semi-liquid blood and blood products and body fluids
contaminated items that would release blood or items that are caked with blood or
other potentially infectious materials; NOT including urine or materials stained with
blood or body fluids
infectious animal waste (research)
Biohazardous Waste Categories
Pathological waste
tissues
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body parts other than teeth
products of conception
fluids removed by trauma or during surgery or autopsy/necropsy or other medical procedure
and not chemically fixed
Animal and plant pathogen waste
Recombinant DNA waste
Sharps
Managing Liquid Biohazardous Waste
Storage:
Label and secure bulk vessels if not disposed of immediately
Treatment:
Chemical disinfection OR
Autoclave
Disinfection
10% bleach solution
 good for general disinfection
 High organics use 20%
 Needs to be made weekly
 Test contact time
Ethanol
 Use 70% solution (most effective)
 Longer contact time and flammable
*Should research and know effectiveness and contact time for the best disinfectant against
your agent!
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Managing Non-Sharp Biohazardous Waste
labeled container
lined with a biohazardous waste bag
equipped with a lid.
Managing Non-Sharp Biohazardous Waste
Securely tie bags for transport to treatment/collection site.
When moving wastes, use secondary containment; avoid using public halls and elevators.
Breakable” Non-sharps Biowaste
Store in labeled containers that are puncture-resistant, closable and will capture leakage
Effective Waste Autoclaving
Leave bag open during autoclaving or loosely closed
Add water to bag prior to autoclaving if primarily dry materials
Steam must contact materials
Place bag in autoclavable tray with sides
Treated Waste Bag Disposal
Allow waste bag to cool
Use fume hood to reduce odors
Securely tie bag shut
Place bag in a non-transparent black bag for regular disposal
Is it a sharps hazard
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Examples:
–
–
needles
–
syringes
–
scalpels
–
all biologically contaminated objects that can easily penetrate skin (Pasteur pipettes,
razor blades, etc.)
Place sharps in approved sharps container for disposal!
Sharps Containers
Containers must be leak-proof, puncture-resistant, closable & labeled with the biohazard
symbol.
Proper sharps containers
must be used for
both clinic and
field work.
Proper Use of Sharps Containers
Place tops on containers before use on lab bench
Don’t forget to date the container when first put into use
Remember: sharps
containers are a
one-way disposal
system
Proper Use of Sharps Containers
Use sharps containers for sharps ONLY!
•
No solid biohazardous waste (i.e. gauze, un-broken pipettes, gloves)
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•
No mercury
thermometers
Sharps Container Disposal
Containers must be permanently closed and disposed of through the animal facility manager:
Within 90 days
of first use
When ¾ full
Disposal methods:
Landfill
Incineration
We use waste hauler
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