Download Biological Hazards

Biological Hazards
Examination Center for Laboratory Safety and Health
Study Aims

To understand the definition and characteristics
of biological hazards (biohazards)

To know the transmission modes of biological
agents

To learn the classification of biohazards

To know the prevention and control methods of
biohazards
2
Outline
Unit 1 Biology Overview
1.1 Biological Classification
1.2 Definition of Biohazards
Unit 2 Sources and Modes of
Transmission
2.1 Sources of Biohazards
2.2 Modes of Transmission
Unit 3 Adverse Effects
3.1 Infection
3.2 Allergy
3.3 Toxic effects
3.4 Others
Unit 4 Biohazard Prevention and
Control
4.1 Prevention
– Classification of Infectious
Microorganisms by Risk Groups
– General Prevention Methods
(Environmental Management &
Personnel Management）
4.2 Control
– Disinfection and Sterilization
– Biological Safety Cabinets
– Temporary Storage and Management
of Biomedical Waste
3
Unit 1 Biology Overview
1.1 Biological Classification

Non-cellular Organisms
– Virus

Prokaryotes
– Archaea
– Eubacteria
Microorganisms

Eukaryotes (Eukarya )
– Fungi
Source: Wikipedia
– Protista
• Photosynthetic (plant-like) protists : algae
• absorptive (fungus-like) protists: no specific name
• ingestive (animal like) protists : protozoa
– Plantae
– Animalia
5
Virus

20-300 nm (1 nm=10-9 m)

non-cellular

nucleic acid (RNA or DNA )
enclosed in a protein coat (capsid)

obligate parasites

specificity

e.g., Influenza viruses (Types A, B,
C), SARS coronavirus, Rabies virus ,
Hantavirus, HIV, Foot-and-mouth
disease virus
Non-cellular Organisms
6
Influenza Virus and
Novel Influenza A (H1N1) Virus

Influenza viruses: type A (causing human influenza
pandemics), type B, type C
– Viral envelope containing two main types of glycoproteins,
hemagglutinin (HA) and neuraminidase (NA)
– The central core containing single-stranded RNA genome
– Common influenza A subtypes: H3N2, H1N1, H5N1 (avian flu)

Novel influenza A (H1N1) virus
– A subtype of influenza A virus
– H1N1 viruses not normally infect humans → reassortment of
swine, avian and human flu genes → human contact with
infected swine → person–to–person transmission →pandemics
7
Prokaryotes
Archaea

existing in harsh environments, such as hot springs, salt
lakes and volcanic vents

different structure of cell membrane and cell wall
compared to bacteria

e.g., halophiles,
thermophiles, alkaliphiles
and acidophiles
http://lesliegottschalk.blogspot.com
8
Prokaryotes
Bacteria




cell structure
0.5-1μm × 2-5 μm (1 μm = 10-6 m)
mostly free-living
e.g., Staphylococcus aureus, Pneumococcus,
Clostridium botulinum , Bacillus anthracis,
Escherichia coli, Mycobacterium tuberculosis.
9
Prokaryotes
Endotoxins

a constituent of the outer
membrane of Gram-negative
bacteria

lipopolysaccharide (LPS)

released into the environment
after lysis of the bacterial cell
or during active cell growth
Source: http://horseshoecrab.org/med/med.html
10
Prokaryotes
Bacterial Exotoxins

mostly from Gram positive bacteria

proteins that a bacterium produces internally
and secretes into its environment

e.g., exotoxins produced by Clostridium tetani,
Clostridium botulinum and Corynebacterium
diphtheriae
11
Prokaryotes
Bacterial Endospores

Function: to resist harsh environment (e.g., heat,
desiccation, UV radiation, chemical disinfectants)

e.g., Bacillus anthracis
Clostridium tetani
https://wikispaces.psu.edu/display/
110Master/Prokaryotes+II++Structure+and+Function
12
Eukaryotes
Fungi

similar to plants

without chlorophyll

releasing enzymes to digest
organic compounds

including molds, yeasts (2-10
μm) and mushrooms (larger
size)

unicellular or multicellular
13
Eukaryotes
Mycotoxins

fungal metabolites

to aid competitiveness and success of colonization of a
fungus over other microorganisms (fungi or bacteria)

cytotoxic: destroying cell structures (e.g., cell
membranes), interfering important process of life (e.g.,
RNA and DNA synthesis)

examples: Aflatoxin , Ochratoxin A
14
Eukaryotes
Fungal Spores

sexual and asexual spores

function – dissemination and
reproduction

characteristic – resistant
Fig 1: Conidiogenous cells and chain of conidia of Aspergillus sp.
http://digiku.nmns.edu.tw/4images/details.php?image_id=44
Fig 2: Halophytophthora spinosa (zoosporangium)
http://digiku.nmns.edu.tw/4images/postcards.php?image_id=45
15
Eukaryotes
Protista (Protoctista）



Photosynthetic (plant–like) protists –Algae
– Photoautotrophs, with chloroplasts
Absorptive (fungus–like) protists
– Chemoheterotroph: phagocytize organism
or excrete enzyme in order to decompose
and absorb organic compounds
Ingestive (animal–like) protists – Protozoa
– meaning “first animals”
– Predatory or parasitic
– e.g., Amoebas, Giardia , Cryptosporidium,
Plasmodium, Paramecium, Foraminifera.
16
Eukaryotes
Higher Plants


Ingest, inhale or contact with plants or their
products
Inhalation: hay fever
– anemophilous flowers
– pollen → allergen
– IgE binds to allergens → release of histamine and
inflammatory mediators
– Allergic rhinitis and allergic conjunctivitis

Contact: latex allergy
– Latex protein
– itchy rash, redness, blisters and scaling
(dermatitis)
– National Taiwan University Hospital 6.8% in
1997
– Hospitals in central Taiwan 8.25% in 1998
Japanese Cedar
Ragweed
17
Eukaryotes
Higher Animals

Sources:
– pets or laboratory animals
– rats, rabbits, cats, dogs, monkeys,
etc.

Exposure routes/modes
– animal bites
– danders
– pets infested with arthropods

Zoonoses
18
Eukaryotes
Arthropods
Arthropods
Lice
Tick
Hosts
Humans, Humans,
dogs,
dogs, etc.
etc.
Fleas
Lice
Cockroaches
Humans,
rats,
cats, etc.
Transmission bites/stings
mode
Tick
Mites
feces, body fragment
Fleas
Mites
Cockroaches
19
Droplet Settling and Retention Time

The time between droplets generated by a patient and
settling onto the floor (20C,1atm)
Diameter of
droplets (μm)
Time
Settling Velocity (cm/s)
10
7~8 min
0.3
5
20~25 min
0.075
1
~14 Hr
0.003
0.1
~20 day
0.000087
20
Droplet Size and Retention Time

Evaporative time for different sizes of droplets (the
influence of temperature is insignificant)
- RH: 50%
Diameter of droplets (μm)
Evaporative Time (sec)
10
0.15
5
0.02
1
0.0017
Diameter of droplets (μm)
Evaporative Time (sec)
10
0.375
5
0.05
1
0.0043
- RH: 80%
21
1.2 Definition of Biohazards

Biological hazards or Biohazards

Biological hazards or biohazards are all of the forms of
life (as well as the nonliving products they produce) that
can cause adverse health effects.
– These hazards are plants, insects, rodents, and other
animals, fungi, bacteria, viruses, and a wide variety of
toxins and allergens.
(Yassi et al., 2001)
22
Unit 2 Sources and Modes of Transmission
2.1 Sources of Biohazards
1.Host: Infected humans or animals
 Human: tuberculosis, influenza,
enterovirus infection
 Animals: rabies, mad cow disease
2. Environmental pathogens
 pollens
 fungi
 Legionella in contaminated
water
24
Routes of Entry

Inhalation (respiratory tract)
tuberculosis, influenza, measles

Ingestion (GI tract)
contaminated food: Typhoid, cholera,
Hepatitis A

Through skin or mucous membranes
Schistosomiasis, trachoma, bloodborne infectious
diseases
25
2.2 Modes of Transmission
1a.HostInhalation
Direct
transmission
Indirect
transmission
droplets
e.g., influenza,
enterovirus infection,
meningococcal meningitis
Inhalation
Airborne (droplet nuclei)
e.g., tuberculosis, measles
26
2.2 Modes of Transmission
1b.HostIngestion
kiss
Direct
transmission
vehicle
Food: enterovirus, Hepatitis A
Contaminated objects: clothes, bedding
Water: Typhoid, cholera
Ingestion
Indirect
transmission
• Mechanical transmission
pathogens are carried to the site of infection, e.g., flies
vector • Biological vector-borne transmission
pathogens need to grow and multiply in vectors, e.g.,
mosquitoes
27
2.2 Modes of Transmission
1c.HostSkin, Mucous membrane
sex, vertical transmission,
bites/stings, physical contact
Direct
transmission
e.g., Syphilis, AIDS, Athlete's
foot, Hepatitis B
sharps (needles, scalpels):
Indirect
transmission
Skin/
Mucous
membranes
Body
fluid/
Blood
e.g., Hepatitis B
transfusion:
e.g., Hepatitis B, AIDS
vector (mosquitoes):
e.g., Dengue fever, malaria
28
2.2 Modes of Transmission
2. Environmental pathogens
fungi
pollen
protozoa
bacteria
others
Air
e.g., hay fever,
legionnaire’s disease
Vehicle (contaminated
water or food)
e.g., aflatoxin poisoning,
cholera
penetration, wounds,
physical contact
e.g., schistosomiasis,
tetanus
Inhalation
Ingestion
Skin/
Mucous
membranes
29
Unit 3 Adverse Effects
Adverse Effects of Biohazards

Infection: growth and multiplication of an infectious agent in the
body (e.g., influenza, measles, tuberculosis)

Allergy: repeated exposure to antigens, which stimulate a specific
immunological response (e.g., allergic pneumonia, asthma, allergic
rhinitis)

Toxicosis : resulting from exposure to toxins produced by
organisms such as bacterial endotoxin and exotoxin, mycotoxin,
etc. (e.g., fever, chill, impairment of lung function)

Others: (e.g., psychological effects)
31
Fir Tree Found Growing in Russian Man’s Lung
Surgeons find fir tree
'growing inside patient's
lung'
Russian surgeons have claimed to
have found a two-inch fir tree
growing inside a man's lung.
The amazing 'discovery' was
apparently made when they opened
up Artyom Sidorkin, 28, to remove
what they thought was a serious
tumor.
http://www.telegraph.co.uk/news/worldnews/europ
e/russia/5152953/Surgeons-find-fir-tree-growinginside-patients-lung.html
32
Psychological effects
33
Unit 4 Biohazard Prevention and Control
4.1 Prevention

Classification of Infectious Microorganisms by Risk
Group
– based on National Science Council Guidelines for
Experiments involving Genetic Recombination 2004（行政
院國家科學委員會93年6月增修版之「基因重組實驗守
則」）
– Other references: NIH Guidelines for Research involving
Recombinant DNA Molecules 2011; U.S. Department of
Health and Human Services Biosafety in Microbiological and
Biomedical Laboratories 2009 (5h Ed); WHO Laboratory
Biosafety Manual 2004 (3rd Ed).
35
Risk Group 1 (RG1) Agents

Agents not associated with disease in healthy adult
humans

Examples
1. Viruses
– adeno-associated virus (AAV) types 1 through 4; and recombinant
AAV constructs, in which the transgene does not encode either a
potentially tumorigenic gene product or a toxin molecule and are
produced in the absence of a helper virus.
2. Bacterial Agents
– asporogenic Bacillus subtilis or Bacillus licheniformis
– nonpathogenic Escherichia coli (Escherichia coli K-12)
36
Risk Group 2 (RG2) Agents

Agents associated with human disease that is rarely
serious and for which preventive or therapeutic
interventions are often available

Examples:
1.Viruses
– Dengue virus serotypes 1, 2, 3 and 4
– Hepatitis A, B, C, D, and E viruses
– Measles virus
– Mumps virus
– Coxsackie viruses types A and B
37
Risk Group 2 (RG2) Agents
2. Bacterial Agents including Chlamydia
– Escherichia coli - all enteropathogenic, enterotoxigenic,
enteroinvasive and strains bearing K1 antigen, including E. coli
O157:H7
– Helicobacter pylori
3. Fungal Agents
– Cryptococcus neoformans
– Penicillium marneffei
4. Parasitic Agents
– Ancylostoma human hookworms
– Heterophyes
– Enterobius
38
Risk group 3 (RG3) Agents

Agents associated with serious or lethal human disease
for which preventive or therapeutic interventions may
be available

Examples:
1. Viruses and Prions
– Transmissible spongioform encephalopathies (TME) agents
(Creutzfeldt-Jacob disease and kuru agents)
– Hantaviruses
– Human immunodeficiency virus (HIV) types 1 and 2
– SARS-associated coronavirus (SARS-CoV)
39
Risk Group 3 (RG3) Agents
2. Bacterial Agents including Rickettsia
– Mycobacterium tuberculosis
– Coxiella burnetii
3. Fungal Agents
– Coccidioides immitis
– Histoplasma capsulatum
– H. capsulatum var. duboisii
40
Risk Group 4 (RG4) Agents

Agents likely to cause serious or lethal human disease
for which preventive or therapeutic interventions are not
usually available

Examples: Viruses
–
–
–
–
Arenaviruses : e.g., Lassa virus
Bunyaviruses: Crimean-Congo hemorrhagic fever virus
Filoviruses : Ebola virus, Marburg virus
Flaviruses (Group B Arboviruses): Tick-borne encephalitis virus
complex
– Herpesviruses (alpha)
– Paramyxoviruses : Equine morbillivirus
41
Relation of Risk Groups to Biosafety Levels, Practices and Equipment
Source: WHO 2004; Laboratory Biosafety Manual, p2.
42
Pathogen Safety Data Sheets and Risk Assessment
http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/index-eng.php
Section I: Infectious Agent
– Name
– Synonym or Cross Reference
– Characteristics
Section II: Hazard Identification
– Pathogenicity/Toxicity
– Epidemiology
– Host Range
– Infectious Dose
– Mode of Transmission
– Incubation Period
– Communicability
Section III: Dissemination
– Reservoir
– Zoonosis
– Vectors
Section IV: Stability and Viability
— Drug susceptibility
— Drug resistance
— Susceptibility to disinfectants
— Physical inactivation
— Survival outside host
Section VII: Exposure Controls
/Personal Protection
– Risk group classification
– Containment requirements
– Protective clothing
– Other precautions
Section V: First Aid /Medical
— Surveillance
— First Aid/Treatment
— Immunization
— Prophylaxis
Section VIII: Handling and
Storage
– Spills
– Disposal
– Storage
Section VI: Laboratory Hazards
— Laboratory-acquired infections
— Sources/Specimens
— Primary Hazards
— Special Hazards
Section IX: Regulatory and Other
Information
– Regulatory information
– Updated
– Prepared by
43

General Prevention Methods
– Environmental Management
– Personnel Management
45
Environmental Management

Source removal (most important
prevention method）

Regular and proper environmental
cleaning and disinfection

Humidity control

Air quality management
46
Air Quality Management

Mechanical ventilation systems
– General ventilation: airflow type and direction
– Local exhaust ventilation: Biosafety cabinet

Air cleaning devices
– High-efficiency particulate air (HEPA) filter
– Germicidal devices

Negative-pressure environments
– Negative pressure isolation room
– Biosafety Level 3 (BSL-3) Laboratory
47
Personnel Management




Personal hygiene (e.g., wash hands)
Personal health management (e.g.,
immunization)
Standard microbiological practices
Personal protective equipment (the last resort
for prevention)
－wear lab coats
－wear gloves and masks
48
Hand Hygiene Technique with Soap and Water
Duration of the entire procedure: 40-60 seconds
49
Source: WHO 2009; WHO Guidelines on Hand Hygiene in Health Care, p156.
50
Standard Microbiological Practices









Restrict or limit access when working
Wash hands before and after work
Decontaminate work surfaces before and after work, and
immediately after spill
Minimize splashes and aerosols
Prohibit eating, drinking, smoking, handling contact lenses and
applying cosmetics in the laboratory
Prohibit mouth pipetting
Use durable, leak proof containers to transport infectious material
Decontaminate infectious waste, including specimens and cultures,
before disposal
Handle sharps with care; place sharps in puncture-resistant
containers used for disposal or transport
51
Minimize splashes and aerosols
Any laboratory
manipulation can
produce aerosols.
Open top test
tubes or containers
are of particular
concern. Measures
can be taken to
minimize these
hazards.
Source: WHO & DIH, http://www.apbtn.org/apbtn/trainingMaterials.html
52
How to Remove Gloves (1)
1.Pinch one glove at the wrist level to remove
it, without touching the skin of the forearms,
and peel away from the hand, thus allowing
the glove to turn inside out
2.Hold the removed glove in the gloved hand
and slide the fingers of the ungloved hand
inside between the glove and the wrist.
Remove the second glove by rolling it down
the hand and fold into the first glove.
3. Discard the removed gloves
http://whqlibdoc.who.int/publications/2009/9789241597906_eng.pdf
53
How to Remove Gloves (2)
Key points：
1. Do not touch the outside of the gloves with bare hands
during the process: gloves to glove and hand to hands
only
2. If the gloves are very dirty, rinse them with water before
removing.
3. Removed gloves must be discarded in a biohazard bag
or receptacle.
54
4.2 Control

Disinfection and Sterilization
– Definitions:
• Disinfection: A physical or chemical means of killing
microorganisms, but not necessarily spores.
• Sterilization: A process that kills and/or removes all classes
of microorganisms and spores.
– Cleaning prior to disinfection and sterilization:
• Dirt, soil and organic matter can shield microorganisms and
can interfere with the killing action of decontaminants
(antiseptics, chemical germicides and disinfectants).
• Precleaning (remove organic compounds) is essential to
achieve proper disinfection or sterilization.
55
Chemical germicides(1) Alcohols

Principle:
– 75% alcohol kills pathogens by denaturing their proteins
(coagulate proteins) and has better efficiency of disinfection.
– 95% alcohol makes pathogens form a protective film ,which
prevents any alcohol from entering the cell, decreasing
disinfection efficiency.

Notice:
– Alcohols are active against vegetative bacteria, fungi and lipidcontaining viruses but not against spores. Their action on nonlipid-containing viruses (e.g., Enterovirus) is variable.
– Alcohols tend to swell and harden rubber and certain plastic
tubing after prolonged and repeated use, as well as bleach
rubber and plastic tiles.
– Simple preparation for 75% alcohol:
95% alcohol: water = 3:1 → approximately 71.25%
56
Chemical germicides(2) Chlorine
(sodium hypochlorite)

Principle:
– Oxidation

Notice:
– A 1:100 dilution of 5% sodium hypochlorite is recommended;
i.e. for household bleach containing 5% sodium hypochlorite,
use 1 part bleach to 99 parts cold tap water (1:100 dilution) for
disinfecting surfaces.
– Bleach may cause irritation to mucous membranes, skin and
respiratory tract; decomposes under light and heat; and reacts
easily with other chemicals to produced toxic gas.
57
Physical agents(1) Ultraviolet Radiation

Principle:
– UV radiation at a wave-length of 254 nm causes
alterations/defects in DNA, which inhibits pathogen
replication.

Notice:
– UV light lacks penetrating power.
Microorganisms beneath dust particles
or beneath the work surface are not
affected by UV radiation.
– Require at least 20 minutes of exposure (contact time), but it
is ineffective in spores and endospores.
– UV rays are harmful to human cells.
58
Physical agents(2) Autoclaving

Principle:
– Applying high-pressure steam (wet heat) to permeate
materials within the autoclave: complete sterilization by
coagulation and denaturation of proteins

Notice:
– Used for items (including containers) resistant to heat and moisture
– For most purposes, the following cycles will ensure sterilization of
correctly loaded autoclaves:
(1) Sterilizing 3 min at 134 °C
(2) Sterilizing 10 min at 126 °C
(3) Sterilizing 15 min at 121 °C
(4) Sterilizing 25 min at 115 °C
– Biomedical waste can be treated as general industrial waste, given
that the waste has been autoclaved as regulated by the Dept. of
Health, Executive Yuan.
59
Physical agents(3) Photocatalyst

Principle:
– When the photocatalyst (TiO2) is illuminated by UV
radiation, electron/hole pairs are produced on the TiO2
surface, generating free radicals to decompose pollutants.

Notice:
– UV radiation with a wavelength of 365nm is needed to excite
the titania catalyst, producing free radicals to facilitate redox
reactions.
– In order to inactivate pathogens, direct contact with the TiO2
surface for at least 30 minutes is required.
– Human body and eyes should not be directly exposed to UV
light.
60
Biological Safety Cabinet
61
Biosafety Cabinet (BSC) vs. Laminar Flow Clean Bench

BSC
– Use clean negative-pressure laminar flow to prevent
emission of contaminated air
– Main purpose: protect the operator, the laboratory
environment and work materials from exposure to
infectious agents

Class II A2
BSC classifications based on the protection efficiency
– Class I: less common
– Class II: commonly used
A. Certification Requirement: NSF/ANSI 49-2007(US
Standard )/BS EN 12469:2000(European Standard )
B. Types: A1, A2(B3 originally), B1, B2
– Class III: provides the highest level of personnel
protection and is used for Risk Group 4 agents.

Positive-pressure laminar flow clean bench: provide
product protection only
62
Positive-pressure Laminar Flow Clean Bench




≠ Biosafety Cabinet
Exhausted outward to operator, providing product protection only
Need to shield glass window (usually use curtain fabrics) while
UV light is on.
Replace the top priminary filter regularly (e.g., every 500 hrs)
Air flow
63
Using Class II Biosafety Cabinet



Open flames should be avoided: create turbulence in the airflow,
compromising protection of both the worker and the work
Do not block the front or rear grille openings: create turbulence in
the airflow, disrupting laminar flow
Ensure that the sash is set in the correct operating position (about
20 cm above the base of the opening )





The top opening is the filtered air outlet which should be cleaned
regularly and cannot be blocked.
Close the sash while the UV light is on.
The primary filter of Type A1 BSC can be changed by lab
personnel regularly
HEPA filter should be replaced by a qualified professional
regularly.
Annual certification is required.
64
Temporary Storage and Management of
Biomedical Waste
(blood, cell and tissue samples, animals)
65
The Definition of Biomedical Waste

Healthcare waste: WHO
– The total waste stream from a healthcare facility, including the
waste generated in the diagnosis, treatment, prevention,
rehabilitation and related research activities.

Biomedical waste: Taiwan
– The waste generated during the process of medical treatment/test,
autopsy, quarantine, research and production of drugs or
biomaterials at healthcare facilities, clinical/medical laboratories,
Biosafety Level 2 and above laboratories of industrial or research
institutes, genetics/biotechnology laboratories and
biotechnology/pharmaceutical factories.
– including genotoxic waste, sharps, infectious waste
66
The Disposal Procedures of Biomedical Waste

Three major steps: storage, transport and disposal

Collect, segregate, pack and label the waste before
storage.
The new and old labels of biomedical waste
Biomedical Waste
Infectious Industrial Waste
(announced on 2007.5.11)
(abolished)
67
Segregation and Storage of Biomedical Waste

Combustible Medical Waste
– Seal and store in a red combustible container and label as
biomedical waste; can be stored up to 1 day at room
temperature, 7 days at 5 C, and 30 days at  0  C.

Non-Combustible Medical Waste
– Seal and store in a yellow unpenetrable container and label
as biomedical waste; need sterilization.
(Date and temperature of storage and the sign of biomedical
waste should be lablled on the container.)
68
Cardboard
containers have
to be sealed;
plastic bags have
to be tied.
Proper label and
symbol in
Chinese
Sturdy
Leak proof
For incineration: red container
For sterilization: yellow container
Only for infectious
waste, not for sharp
devices
Figure 2-15 The storage containers for infectious waste
Source: Taiwan EPA 2008; Handbook of Medical Waste Management.
69
with a fitted
cover
Proper label
and symbol in
Chinese
Sturdy and
punctureresistant (made
of metal or
rigid plastic)
Leak-proof
Sharps
containers
Figure 2-14 The containers for sharp waste
Source: Taiwan EPA 2008; Handbook of Medical Waste Management.
70
Combustible
Waste
Use leak-proof containers fitted
with covers
NonCombustible
Waste
Discard disposable sharps (e.g.,
needles and scalpel blades) into
puncture-proof (made of metal or
high-density plastic ) and rigid
containers fitted with covers
Disinfect or autoclave contaminated (with Waste containing infectious agents can be treated
potential infectivity) reusable materials
as industrial waste after sterilization (e.g., gloves,
(e.g., glass pipettes, serum bottles)
disposable centrifuge tubes, blood collection tube
and etc.)
71
Contaminated (with potential infectivity) materials that
can be reused after sterilization or autoclaving
inappropriate
0.5% bleach
 Any contaminated (with potential infectivity)
reusable materials should not be cleaned prior
to autoclaving/sterilization.
 Any necessary washing or repair should be
done after autoclaving/sterilization.
Vertical soak (not completely immersed)
Horizontal soak (aspirate disinfectant
before removing the pipette dispenser,
and then immerse the whole pipette in
the disinfection box)
Examples:
1. Pipettes used for RG1 and general cell culture
should be immersed in the disinfectant first and then
washed.
2. Reusable materials (e.g., glass pipettes, serum
bottles) used to handle RG2 and above infectious
materials can be soaked in the disinfectant first,
autoclaved, and then washed.
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Temporary Storage and Disposal of
Animal Carcass




Install sufficient refrigerators in animal rooms to store animal
carcasses temporarily.
After removing from the freezer, thaw the carcass before incineration
to prevent incomplete combustion and waste of fuel; defrost the
carcass in an appropriate place to prevent contamination by melting
water (use a leak-proof container).
Send innocuous animal carcasses directly to landfill or incineration;
infectious animal carcasses should be packaged in the biohazard
labeled plastic bags, autoclaved and then treated as innocuous animal
carcasses.
Radioactive animal carcasses should be packaged in the plastic
radioactive waste bags and dried under 60-70C using a specialized
oven; using a microwave to heat and dehydrate animal carcasses can
prevent odor generated during the process; dehydrated animal
carcasses can then be treated as radioactive waste.
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Contaminated biological materials that can be incinerated
directly or incinerated after sterilization
(e.g., organs or carcasses of innocuous or infectious animals)
74
Current Laboratory Waste Disposal in
Academic Institutes in Taiwan
Waste Control, Decontamination Without BSC (BSL1)
and Management
(N=121)
Proper segregation and
storage of infectious waste
Sterilization of infectious
waste before disposal
With BSC (BSL2)
(N=161)
74
61.2%
136
84.5%
103
85.1%
151
93.8%
Source: Taiwan IOSH 2006; Investigation of Facility and Installation at
Biosafety-Level-2 Laboratories (IOSH95-H101).
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Current Laboratory Waste Disposal in
Academic Institutes in Taiwan (cont.)
Not using leak proof container
and uncovered
Not using leak proof
container and uncovered
Source: Taiwan IOSH 2006; Investigation of Facility
and Installation at Biosafety-Level-2 Laboratories
(IOSH95-H101).
Not using the biomedical
waste bag resistant to
high temperature and
pressure
76