1. Session 3
Laboratory Safety Training
Chemical Risk Management

2. Toxic effects of Laboratory
Chemicals
 In order to minimize the hazards
associated with chemicals used in the
laboratory the researcher must investigate
many sources of information to safely
design the experiment. There are many
ways to do this. The starting point should
be with a review of the MSDS.
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3. Hazard Communication
 Hazard Communication Standard
 29CFR 1910.1200
– OSHA published in 1988, requires, chemical
manufacturers or importers to evaluate the
hazards of the products they supply and
summarize this information on Material Safety
Data Sheets (MSDS), shipping labels, and
product warnings
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4. Hazard Communication
 Employers must supply this information to their
employees and provide training on:
– The chemical hazards found in their work place. This
includes training on reading hazard labels and MSDS,
physical and health hazards of the chemicals, how to
detect releases, the use of any required personal
protective equipment (PPE), and the details of the
hazard communication program.
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5. Hazard Communication
 Specific laboratory requirements include:
– Ensuring all incoming chemical containers are
labeled,
– MSDS are received with incoming chemicals and are
readily accessible to laboratory employees at all
times, while working in their labs,
– Ensure all laboratory, employees are trained on the
physical and health hazards associated with the
chemicals used including:
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6. Hazard Communication
 Methods and observations that may be
used to detect the presence or release
hazardous chemicals in the work area,
 The measures employees can take to
protect themselves from chemical hazards,
such as work practices, emergency
procedures, and PPE.
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7. Hazard Communication
 Laboratories that ship hazardous chemicals
are considered either a chemical
manufacturer or distributor under this
standard and must also comply with the
shipping requirements, including labeling
containers, using proper shipping names
and preparing an MSDS to be provided to
the recipients
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8. Each MSDS must contain the
following information:
1. Suppliers name, 1. Physical hazards,
address, ph #, date, including reactivity,
2. Chemical name, CAS 2. Health hazards,
# of all hazardous including signs and
ingredients if it is > 1% symptoms of
of the product, exposure, medical
3. Physical and chemical conditions that
characteristics, vp., fp., might be aggravated
by exposure,
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9. Each MSDS must contain the
following information:
1. Primary routes of 1. Emergency and first
entry, aid procedures,
2. PELs, RELs, TLVs 2. Disposal
3. Toxicity data, considerations
4. Storage and 3. Transportation
handling data, information
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10. Additional sources of hazard
information
 National Fire Protection Association NFPA 704
 National Institute of Occupational Safety and
Health (NIOSH) RELs.
 American Council of Governmental Hygienists
(ACGIH) TLVs
 International Agency for Cancer Research,
(IARC)
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11. Additional sources of hazard
information
 National library of Medicine (NLM)
 Toxline, Medline
 Hazardous substance Data Base (HSDB)
 Registry of Toxic Effects of Chemical
Substances (RTECS)
 MSDS database e.g. SIRI
http://www.SIRI.org
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12. Other hazard classification
systems
 The NFPA 704 System is a means of providing hazard
information for a material. Each of the four sections is
associated with a particular hazard and the higher the
number the more hazardous the material is for that
particular characteristic. The fourth section is to give
information on special hazards. Next are the four
sections and an explanation of each.
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13. Red=Flammability
•
4-Materials with a flashpoint below
73 F (22 C) and a boiling point below 100 F.
3-Materials with a flashpoint below 73 F and a boiling
point greater than or equal to 100 F (38 C) or a
flashpoint above 73 F and less than 100 F.
2-Materials with a flashpoint above 100 F, but not
exceeding 200 F (93.3 C).
1-Materials with a flashpoint above 200 F.
0-Materials which normally won't burn.
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14. Blue-Health Hazard
4-Materials with an oral LD50 of less than or equal to 5 mg/
kg.
3-Materials with an oral LD50 above 5, but less than 50 mg/
kg.
2-Materials with an oral LD50 above 50, but less than 500
mg/kg.
1-Materials with an oral LD50 above 500, but less than
2000mg/kg.
0-Materials with an oral LD50 above 2000mg/kg.
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15. Yellow=Reactivity Hazard
4-Material is capable of explosion or detonation at
normal temperature and pressure.
3-Material is capable of explosion, but requires a
strong initiating source, or the material reacts
with water.
2-Material undergoes violent chemical changes at
elevated temperature and pressure.
1-Normally stable, but can become unstable at
elevated temperatures.
0-Normally stable.
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16. White = Special Hazard
W Water Reactive
Ox Oxidizer
COR Corrosive
Radiation
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17. Routes of Exposure
 Inhalation - Most common route of
exposure, lungs are designed for maximum
transport and adsorption of vapors, large
surface area (1000 sf)
 Dermal – Second most common route of
exposure, lipid (pass with greater ease) and
water soluble chemicals can pass through
the skin. Has 20 sf surface area.
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18. Routes of Exposure
 Ingestion – can occur through food
contamination, eating drinking in lab, poor
hygiene, mucociliary transport of vapors
trapped in upper air ways,
 Injection – Can occur through injury and
needle sticks
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19. Lethal Concentration
 Lethal Concentration- LC-50, pertains to
inhalation hazards. It is the concentration
of a material in air that will kill 50% of the
test subjects when administered as a single
exposure (typically 1 to 4 hours). This
value gives you an idea of the relative
toxicity of the material. This value applies
to vapors, dusts, mists and gases.
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20. Lethal Dose
 An LD50 value is the amount of a solid or
liquid material that it takes to kill 50% of
test animals in one dose. The dose may be
administered orally (by mouth), or
injection into various parts of the body.
The value is usually reported along with
the administration method.
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21.
Acute Toxicity Levels
Toxicity LD-50 LD-50(rab LC- 50 Probable
lethal human
(rats) bits) (rats) dose
Extremely <1mg <10ppm 10ppm
< A taste, 1
Toxic
grain
Highly 1-50 mg 10-100 10-100 1 tea, 4
Toxic ppm ppm cc
Moderately 50-500 100-1000 100-1000 1 oz, 30g.
Toxic mg ppm ppm
Slightly 500-5000 1000-10,0 1000-10,0 1 pint,
Toxic mg 00 00 250g
Mg//kg body weight
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22. Acute Toxins
 Acute toxicity is the ability of a chemical
to cause harm after a single exposure.
They can cause local, or systemic effects
or both. Chemicals that have a high level
of acute toxicity (very low LD, LC-50s)
are defined as particularly hazardous
substances by the Lab Standard and
require special handling procedures to be
added to the lab CHP.
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23. Acute Toxins
 These include: acrolein, arsine, chlorine,
diborane, diazomethane, hydrogen
cyanide,hydrogen floride, sodium cyanide,
dimethyl mercury, etc.
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24. Chronic Toxicity
 Harm occurs through repeated usually
lower levels of exposure. Includes most
carcinogens, reproductive hazards, some
heavy metals. Many have a long latency
period. Generally the longer the exposure
the greater the hazard.
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25. Factors affecting toxicity
 The potential for toxic effects is
determined by the dose, the duration, the
frequency and the route of exposure.
 Synergistic effects - the combination of the
toxic effects of two substances may be
significantly greater than the toxic effect
of either substance alone.
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26. Reproductive toxins
 Reproductive toxins are those that have an
adverse effect on reproduction including:
fertility, gestation, lactation and general
reproduction performance. Mutagens
affect the genetic material. Teratogens
effect the development of the fetus.
Ethylene dibromide and
dibromochloropropane are well known
male reproductive toxins. Others include:
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27. Reproductive toxins cont.
 vacetaldehyde, acrylicacid, aflatoxins, aniline
arsenic, benzene, benzo(a)pyrene, cadmium,
carbondisulfide, chromic acid, chloroform,
chloroprene, N,N-dimethylacetamide,
dimethylformamide (DMF), dimethyl sulfoxide
(DMSO), dinitrooctylphenol ,di-sec-octyl-
phthalate, diphenylamine, dithane, estradiol, 2-
ethoxyl ethanol, 2-ethoxyetyl acetate, ethyl
thiourea, 2-ethylhexanol, formaldehyde,
formamide, glycol ethers, halothane,
hexachlorobenzene, hexafluoroacetone,
hydrazine(s),
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28. Reproductive toxins cont.
 iodoacetic acid, karathane, lead compounds,
mercury compounds, 2-methoxy ethanol, 2-
methoxy- ethylacetate, methylchloride, N-
methyl-2-pyrolidone, nitrobenzene, nitrousoxide,
phenol, polychlorinated and polybrominated
biphenyls, propylene glycol, monomethyl ether,
propylene glycol, monomethyl ether acetate,
propylene oxide, systhane,
TOK(herbicide),toluene, trichloroethylene, vinyl-
chloride, xylene
 Additional information @ Reproductive Hazards
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29. Medical Surveillance programs
 Use of certain chemicals at particular
exposure levels require the participation a
medical surveillance programs.
 Medical Screening/Surveillance
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30. Carcinogens
 Chemical capable of causing changes in
the DNA resulting in uncontrolled growth
of cells or cancer. They are insidious
because no immediate harmful effects are
felt. Latency period can be from 20-30
years
 Usually results from chronic exposures
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31. Carcinogens
 Defined in the Lab Standard as a chemical that
is:
– Regulated by OSHA as a carcinogen,
– It is listed by the National Toxicology Program,
– It is listed as a group 1 under IARC (international
agency on cancer research),
– It is listed as a group 2A, or 2B under IARC probable
and possibly carcinogenic to humans.
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32. Carcinogens
 Examples of "Select Carcinogens“
 Examples of “Classes of Carcinogens”
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33. Conclusion
 Risk assessment for use of hazardous
chemicals includes:
1. Identify chemicals to be used and
circumstances of use,
2. Consult sources of information,
3. Evaluate type of toxicity,
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34. Conclusion
1. Consider possible routes of exposure,
2. Evaluate quantitative information on toxicity,
3. Select appropriate procedures to minimize
exposure following hierarchy of protection,
a. Eliminate the hazard
b. Substitute or reduce the hazard
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35. Conclusion
b. Engineering Controls – Fume Hood, Glove boxes
c. Administrative Controls – CHP, SOPs
d. Personal Protective Equipment – gloves, goggles
2. Prepare for contingencies.
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