MOLECULAR BIOLOGY & DIAGNOSTICS
P-LEC1: BIOSAFETY, BIOSECURITY, WASTE
MANAGEMENT IN MOL BIO LABORATORY
Transcriber: Langit, John Bern R. | Professor: Prof. Mark Ryan V. Domingo
1.0 BIOSAFETY AND BIOSECURITY
Biosafety:
 Containment principles, technologies and practices that are
implemented to prevent unintentional exposure to biological
agents or their inadvertent release (WHO).
 It is the application of safety precautions that reduce the
laboratory workers’ risk of exposure to a potentially infectious
microorganism and limit the contamination of the work
environment and, ultimately, the community.

Biohazards:
 a risk to human health or the environment arising
from biological work, especially with
microorganisms.
Biosecurity:
 Principles, technologies and practices that are implemented for
the protection, control and accountability of biological
materials and/or the equipment, skills and data related to their
handling. It aims to prevent their unauthorized access, loss,
theft, misuse, diversion or release (WHO).
Biosafety & Biosecurity:
•
Addressing laboratory biosecurity risks, in many ways, parallel
a complement set of biosafety risk management. Effective
biosafety practices are the foundation of laboratory biosecurity.
These two must work hand in hand in handling biological
materials properly to control the risks of exposing the
community.
Principles of Biosafety:
•
Containment:
 It describes safe methods for managing infectious
materials in the laboratory environment where they
are being handled or maintained.
 It is “to reduce exposure.”
•
Biosafety Levels
2.0 BIOSAFETY LEVELS
Biosafety Levels:
•
There are four biosafety levels.
1. BSL-1 (Low Risk Microbes)
2. BSL-2
3. BSL-3
4. BSL-4 (High Risk Microbes)
•
Each level has specific controls for containment of microbes
and biological agents.
•
The primary risks that determine levels of containment are:
a) infectivity (of microorganism),
b) severity of disease,
c) transmissibility (mabilis bang kumalat?), and the
d) nature of the work conducted
e) origin of the microbe, or the agent in question,
and the route of exposure are also important.

Difference: Biosafety and Biosecurity
Biosafety
Biosecurity
•
―
―
―
―
―
―
protects people from
biohazards
prevent unintentional
exposure to biohazards
protects people and the
environment from exposure
to harmful biological
materials
maintaining containment
preventing exposure
emergency response
protocols
―
―
―
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―
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―
protects biohazards from
people
protection, control and
accountability for valuable
biohazards within laboratories
prevent unauthorized access,
loss, theft, misuse, diversion
or intentional release
prevents misappropriation and
misuse of potentially harmful
biological agents
secure storage
limited access
inventory of stock
Route of Exposure:
 It refers to the way a microbe gains access to a
living organism.
•
There are four main routes of exposure
1. Percutaneous, though broken or
damaged skin
2. Inhalation (respiratory transmission)
3. Mucous membranes of the eyes,
nose, and mouth
4. Ingestion
Each biosafety level has its own specific containment controls
that are required for the following:
 Laboratory Practices
 Safety Equipment
 Facility Construction
Biosafety Levels
Bioterrorism:
 is terrorism involving the intentional release or
dissemination of biological agents. These agents include
bacteria, viruses, insects, fungi, and/or toxins, and may be in a
naturally occurring or a human-modified form, in much the
same way as in biological warfare.
Page 1 of 6
•
The biosafety levels range from BSL-1 to BSL-4. Each
biosafety level builds on the controls of the level before it.
Every microbiology laboratory, regardless of biosafety level,
follows standard microbiological practices.
BSMT 2, SEMESTER 2

Level
BSL-1
BSL-2
BSL-3
BSL-4
•
1ST PRELIMINARY TERM
COURSE: MOLECULAR BIOLOGY & DIAGNOSTICS
Standard Microbiological Practices:
 These are those practices that are common
to all laboratories.
•
These practices may include:
 Not eating, drinking, or applying
cosmetics in the lab
 Washing hands after working
with infectious materials and
before leaving the lab
 Routinely decontaminating work
surfaces
Table: Biosafety Levels
Containment Control
Examples
Microbes not known to  skin bacteria
consistently cause
 yeast
disease in
 E. coli (nonimmunocompetent adult
pathogenic strains)
humans, of minimal
potential hazard to
laboratory personnel
and the environment.
Microbes pose
 herpes simplex
moderate potential
 common cold viruses
hazard to personnel
(RSV, rhinoviruses)
and the environment.
 salmonella
 Staphylococcus
aureus
Indigenous or exotic
 Mycobacterium
microbes that may
tuberculosis
cause serious or
 SARS-CoV-2
potentially lethal
 highly pathogenic
disease via inhalation
avian influenza
(respiratory
 plague (Yersinia
transmission).
pestis)
Exotic agents that pose
 Ebola virus
a high risk of aerosol smallpox virus
transmitted laboratory
* konti lang yung BSL-4
infections and lifelaboratories in the world
threatening disease
that is frequently fatal,
for which there are no
vaccines or treatments.

Biohazard Wastes:
 aka infectious wastes or biomedical wastes
 is any waste containing infectious materials or
potentially infectious substances such as blood.
 blood samples
 bodily fluids
 microorganisms
 culture plates with cultures
•
must be decontaminated first before disposal!!!
a) autoclaving
b) adding chlorox (usually 10%)
c) incinerated (this is done before)

Solid Waste:
•
has to be autoclaved in special biohazard bags at
121°C for 20 min.
 paper towels
 culture medium
 agar
 solid materials in contact with cells
 petri dish
 pipette tips
 cuvettes
Liquid Waste:
•
either disinfected with 10% bleach solution 30 min,
or autoclaved at 121°C for 20 min, and then poured
down the sink.
•
Aspirate liquid from disposable plates, dishes, tubes,
bottle, and flasks before throwing the containers into
solid biohazard waste.
•
Reusable flasks and bottles are either rinsed with
10% bleach or autoclaved

Chemical Waste Disposal:


The required BSL for handling SARS-CoV2 is either BSL-2
or BSL-3.
 BSL-3: Culture, isolation, characterization of SARSCoV2.
 BSL-2: Enough for routine diagnostic testing (e.g.
RT-PCR, antigen testing).
Biological Waste and its Disposal:
•
•
Put sharp items, such as needles, in a special sharps disposal
box and are usually treated as biohazard material.
Put any broken glass in a box or container dedicated to that
purpose. If the glass contained biohazard material, it must be
autoclaved first.
Of special concern are sharp wastes such as needles, blades,
glass pipettes, and other wastes that can cause injury during
handling.
Page 2 of 6
Acids:
•
Bases:
•

Small amount (<100 mL) may be neutralized (check
with pH paper) and slowly poured down the drain
with large amounts of water. Large amounts are
handled as hazardous chemical waste.
Small amount (<100 mL) may be neutralized (check
with pH paper) and slowly poured down the drain
with large amounts of water. Large amounts are
handled as hazardous chemical waste.
Acids and bases that are in large amount (>100 mL)
should be considered as hazardous chemical waste
already.

Buffers:
•
Most buffers can be poured down the sink.

Hazardous Chemical Waste:
•
Generally, chemicals should not be mixed.
•
When mixing is done, it is for small volumes of
solvents from the same category; for example, all
halogenated solvents.

Solvents:
•
Usually flammable.
•
Hazardous chemical waste: do not pour down the
sink.
•
Use a waste container with a volume as close as to
that of the waste as possible.
•
Do not combine different solvents.
•
Examples: Methanol, hexane. methane
3.0 BIOLOGICAL WASTE & ITS DISPOSAL
•
LANGIT 2023
BSMT 2, SEMESTER 2
1ST PRELIMINARY TERM
COURSE: MOLECULAR BIOLOGY & DIAGNOSTICS

Non-hazardous Chemical Waste:
•
Dispose of as trash if solid.
•
Liquids should be flushed down the drain in the
laboratory sink, followed by large amounts of water.

Dry Ice:
•
Allow the dry ice to evaporate in the ice bucket or
container.
•
Do not dispose of it down the sink, even while
running the water, because the pipes can freeze and
crack.
REFERENCES



PPT Handout 2023 (Prof. Mark Ryan Domingo)
Class Video Recording 2023 (Prof. Mark Ryan Domingo)
Supplementary Reading Material: WHO Laboratory Biosafety
Manual, 4E
Biohazard Symbol
Page 3 of 6
LANGIT 2023
BSMT 2, SEMESTER 2
1ST PRELIMINARY TERM
COURSE: MOLECULAR BIOLOGY & DIAGNOSTICS
RECALL QUESTIONS
1.
Match:
a.
b.
c.
d.
e.
f.
g.
h.
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Biosafety
Biohazards
Biosecurity
Bioterrorism
Containment
Route of Exposure
Standard Microbiological Practices
Biohazard Wastes
a risk to human health or the environment arising
from biological work, especially with
microorganisms.
It is “to reduce exposure.”
Containment principles, technologies and practices
that are implemented to prevent unintentional
exposure to biological agents or their inadvertent
release (WHO).
aka infectious wastes or biomedical wastes
These are those practices that are common to all
laboratories.
is any waste containing infectious materials or
potentially infectious substances such as blood.
is terrorism involving the intentional release or
dissemination of biological agents.
Principles, technologies and practices that are
implemented for the protection, control and
accountability of biological materials and/or the
equipment, skills and data related to their handling.
It is the application of safety precautions that reduce
the laboratory workers’ risk of exposure to a
potentially infectious microorganism and limit the
contamination of the work environment and,
ultimately, the community.
It aims to prevent their unauthorized access, loss,
theft, misuse, diversion or release (WHO).
It describes safe methods for managing infectious
materials in the laboratory environment where they
are being handled or maintained.
It refers to the way a microbe gains access to a
living organism.
4.
Biosafety & Biosecurity:
a. Addressing laboratory biosecurity risks, in many
ways, ___ a complement set of biosafety risk
management.
b. Effective ___ practices are the foundation of
laboratory ___. These two must work hand in hand
in handling biological materials properly to control
the risks of exposing the community.
6.
Match: (a) Biosafety & (b) Biosecurity
― protects biohazards from people
― emergency response protocols
― limited access
― prevent unauthorized access, loss, theft, misuse,
diversion or intentional release
― protects people from biohazards
― inventory of stock
― maintaining containment
― prevents misappropriation and misuse of potentially
harmful biological agents
― preventing exposure
― prevent unintentional exposure to biohazards
― protection, control and accountability for valuable
biohazards within laboratories
― protects people and the environment from exposure
to harmful biological materials
― secure storage
Answer: BABBABABAABAB
1.0 BIOSAFETY & BIOSECURITY
3.
5.
7.
Bioterrorism:
a. is ___ involving the ___ release or dissemination of
biological agents. These agents include bacteria,
viruses, insects, fungi, and/or toxins, and may be in
a naturally occurring or a human-modified form, in
much the same way as in biological ___.
8.
9.
Enumerate: Principles of Biosafety (2)
Containment:
a. It describes safe ___ for ___ infectious materials in
the ___ environment where they are being handled
or maintained.
b. It is “to ___ ___.”
2.0 BIOSAFETY LEVELS
Answer: BEAHGHDCACEF
2.
LANGIT 2023
Biosafety:
a. ___, ___ and ___ that are implemented to prevent
___ ___ to biological agents or their ___ ___
(WHO).
b. It is the application of ___ that reduce the laboratory
workers’ risk of ___ to a potentially infectious
microorganism and limit the ___ of the ___
environment and, ultimately, the ___.
Biohazards:
a. a ___ to ___ health or the ___ arising from
biological ___, especially with ___
Biosecurity:
a. ___, ___ and ___ that are implemented for the ___,
___ and ___ of biological materials and/or the
equipment, skills and data related to their ___. It
aims to prevent their ___ ___, ___, ___, ___, ___ or
___ (WHO).
Page 4 of 6
10. Biosafety Levels:
a. How many levels?
b. Which among the biosafety level has the low risk
microbes?
c. Which among the biosafety level has the high risk
microbes?
d. Label:
e.
f.
Each level has specific ___ for ___ of microbes and
biological agents.
Enumerate: The primary risks that determine
levels of containment are: (5)
i. ___ (of microorganism),
BSMT 2, SEMESTER 2
1ST PRELIMINARY TERM
COURSE: MOLECULAR BIOLOGY & DIAGNOSTICS
___ of ___,
___ (mabilis bang kumalat?), and the
___ of the ___ conducted
___ of the ___, or the agent in question,
and the ___ are also important.
g. Enumerate: Each biosafety level has its own
specific containment controls that are required
for the following: (3)
i. ___
ii. ___
iii. ___
11. Route of Exposure:
a. It refers to the ___ a microbe gains ___ to a living
organism.
b. Enumerate: There are four main routes of
exposure (4)
i. ___, though broken or damaged skin
ii. ___ (respiratory transmission)
iii. ___ of the eyes, nose, and mouth
iv. ___
―
―
―
ii.
iii.
iv.
v.
12. The biosafety levels range from BSL-1 to BSL-4. Each
biosafety level builds on the ___ of the level before it. Every
microbiology laboratory, regardless of biosafety level,
follows standard ___.
13. Standard Microbiological Practices:
a. These are those practices that are ___ to all
laboratories.
b. These practices may include:
i. Not eating, drinking, or applying
cosmetics in the lab
ii. Washing ___ after working with infectious
materials and before leaving the lab
iii. Routinely ___ work surfaces
14. Match:
a.
b.
c.
d.
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SARS-CoV-2
highly pathogenic avian influenza
herpes simplex
Answer: CDBA | BDCDAAABCBCCB
15. Supply:
Level
BSL-1
BSL-2
BSL-3
BSL-4
BSL-1
BSL-2
BSL-3
BSL-4
•
Indigenous or exotic microbes that may cause
serious or potentially lethal disease via inhalation
(respiratory transmission).
Exotic agents that pose a high risk of aerosoltransmitted laboratory infections and life-threatening
disease that is frequently fatal, for which there are
no vaccines or treatments.
Microbes pose moderate potential hazard to
personnel and the environment.
Microbes not known to consistently cause disease in
immunocompetent adult humans, of minimal
potential hazard to laboratory personnel and the
environment.
LANGIT 2023
Table: Biosafety Levels
Containment Control
Examples
Microbes ___ ___ to
 skin bacteria
___ ___ in
 yeast
immunocompetent adult  E. coli (nonhumans, of minimal
pathogenic strains)
potential hazard to
laboratory personnel
and the environment.
Microbes pose ___ ___
 herpes simplex
___ to personnel and
 common cold viruses
the environment.
(RSV, rhinoviruses)
 salmonella
 Staphylococcus
aureus
Indigenous or exotic
 Mycobacterium
microbes that may
tuberculosis
cause ___ or potentially  SARS-CoV-2
___ ___ via ___ (___).
 highly pathogenic
avian influenza
 plague (Yersinia
pestis)
Exotic agents that pose
 Ebola virus
a ___ ___ of ___ smallpox virus
transmitted laboratory
___ and ___-threatening * konti lang yung BSL-4
laboratories in the world
___ that is frequently
fatal, for which there
are no vaccines or
treatments.
The required BSL for handling SARS-CoV2 is either BSL-___
or BSL-___.
 BSL-3: ___, ___, ___ of SARS-CoV2.
 BSL-2: Enough for ___ ___ testing (e.g. ___, ___).
3.0 BIOLOGICAL WASTE & ITS DISPOSAL
salmonella
smallpox virus
Mycobacterium tuberculosis
Ebola virus
E. coli (non-pathogenic strains)
skin bacteria
yeast
common cold viruses (RSV, rhinoviruses)
plague (Yersinia pestis)
Staphylococcus aureus
Page 5 of 6
16. Biological Waste and its Disposal:
a. Put ___ items, such as ___, in a special ___ ___ ___
and are usually treated as ___ material.
b. Put any ___ ___ in a box or container dedicated to
that purpose. If the glass contained biohazard
material, it must be ___ first.
c. Of special concern are sharp wastes such as needles,
blades, glass pipettes, and other wastes that can
cause ___ during handling.
17. Biohazard Wastes:
a. aka ___ wastes or ___ wastes
b. is any waste containing infectious ___ or potentially
infectious ___ such as ___.
 blood samples
 bodily fluids
 microorganisms
 culture plates with cultures
c. must be ___ first before disposal!!!
d. What are the decontamination methods? (3)
BSMT 2, SEMESTER 2
1ST PRELIMINARY TERM
COURSE: MOLECULAR BIOLOGY & DIAGNOSTICS
18. Match:
a.
b.
c.
d.
e.
f.
g.
h.
i.
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―
LANGIT 2023
Chemical Waste Disposal:
Solid Waste
Liquid Waste
Acids
Bases
Buffers
Hazardous Chemical Waste
Solvents
Non-hazardous Chemical Waste
Dry Ice
21. Acids:
a.
22. Bases:
a.
Most can be poured down the sink.
Do not dispose of it down the sink, even while
running the water, because the pipes can freeze and
crack.
Reusable flasks and bottles are either rinsed with
10% bleach or autoclaved
has to be autoclaved in special biohazard bags at
121°C for 20 min.
Aspirate liquid from disposable plates, dishes, tubes,
bottle, and flasks before throwing the containers into
solid biohazard waste.
When mixing is done, it is for small volumes of
solvents from the same category; for example, all
halogenated solvents.
either disinfected with 10% bleach solution 30 min,
or autoclaved at 121°C for 20 min, and then poured
down the sink.
Hazardous chemical waste: do not pour down the
sink.
Generally, chemicals should not be mixed.
Dispose of as trash if solid.
Do not combine different solvents.
Small amount (<100 mL) may be neutralized (check
with pH paper) and slowly poured down the drain
with large amounts of water. Large amounts are
handled as hazardous chemical waste.
Liquids should be flushed down the drain in the
laboratory sink, followed by large amounts of water.
Use a waste container with a volume as close as to
that of the waste as possible.
Allow to evaporate in the ice bucket or container.
Usually flammable.

___ amount (<___ mL) may be ___ (check with ___
paper) and slowly poured down the drain with ___
amounts of ___. Large amounts are handled as ___
chemical waste.
___ amount (<___ mL) may be ___ (check with ___
paper) and slowly poured down the drain with ___
amounts of ___. Large amounts are handled as ___
chemical waste.
Acids and bases that are in ___ amount (>___ mL) should
be considered as ___ chemical waste already.
23. Buffers:
a. Most buffers can be ___ ___ the ___.
24. Hazardous Chemical Waste:
a. Generally, chemicals should not be ___.
b. When mixing is done, it is for ___ volumes of
solvents from the same ___; for example, all
halogenated ___.
25. Solvents:
a. Usually ___.
b. ___ chemical waste: do not ___ ___ the ___.
c. Use a waste ___ with a ___ as ___ as to that of the
___ as possible.
d. Do not ___ different solvents.
e. Examples: Methanol, hexane. methane
26. Non-hazardous Chemical Waste:
a. Dispose of as trash if ___.
b. Liquids should be ___ ___ the ___ in the laboratory
sink, followed by ___ amounts of ___.
27. Dry Ice:
a. Allow the dry ice to ___ in the ___ ___ or ___.
b. Do not dispose of it down the ___, even while ___
the ___, because the ___ can ___ and ___.
Biohazard Symbol
Answer: EIBABFBGFHG C&D HGIG
19. Solid Waste:
a. has to be autoclaved in special ___ ___ at ___°C for
___ min.
 paper towels
 culture medium
 agar
 solid materials in contact with cells
 petri dish
 pipette tips
 cuvettes
20. Liquid Waste:
a. either ___ with ___% ___ solution ___ min, or ___
at ___°C for ___ min, and then ___ ___ the ___.
b. ___ liquid from disposable plates, dishes, tubes,
bottle, and flasks before throwing the containers into
___ biohazard waste.
c. Reusable flasks and bottles are either ___ with
___% ___ or ___
Page 6 of 6