Transcript CHEMICAL WARFARE - Welcome to the National Civil Defence

CHEMICAL SAFETY IN
SCHOOLS/COLLEGES – REDUCING
RISKS TO YOUNG PEOPLES
Dr. M.K.N. Yenkie
Professor of Chemistry
Registrar – RTM Nagpur University
Director - Laxminarayan Institute of Technology
R.T.M. Nagpur University
Nagpur - 440 033
Periodic Table of the Elements
• Elements are
arranged by
atomic
number
• Elements in
the same
vertical
columns
have similar
properties
“Halogens”
“Alkali Metals”
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CHEMICALS
• Chemicals have invaded all sectors of human
life
• Possess inherent dangers
Chemistry has the potential to solve the
mysteries of life. However, NO CHEMICAL
IS TOTALLY SAFE OR NON HAZARDOUS
ONLY SAFE WAY OF HANDLING THEM
Dangers associated with chemicals
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Storing raw material
Production site
Storing products
Transport
Lab Chemicals
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Acids and Bases
Permanganate
Salts
Burners
H2S
Chemicals used at Home
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Acids and Bases
Permanganate
Salts
Burners
Bleaching powder
Insecticides
Protection of grains
Ammonia
• Anhydrous Ammonia
– pH>12; (household ammonia pH < 12)
– Wide industrial use
• Plastics, fertilizer, explosives
– Irritating, corrosive; causes necrosis, severe pain
– Serious injury to eyes, lungs, skin, GI tract
• Management
– Remove from exposure, decontaminate
– Symptomatic; maintain airway
Ammonia
Chemical Formula: NH3
CAS# 7664-41-7
UN#1005
ISCS: 0414
Physical State: Colorless , compressed liquefied gas, with pungent odor
Physical Properties
• Boiling Point: -33°C
• Relative Density: 0.7 at -33°C
• Vapor Density: 0.59
• Solubility in water 54 g/100mL, 20°C
• Vapor Pressure, 1013 kPa at 26°C
• Explosive Limits, vol% in air: 15-28
• Auto-ignition temperature: 651°C
Fire and Explosion: Flammable; gas/air mixtures are
explosive.
Health Hazards Corrosive to eyes, skin, respiratory
tract. Inhalation results in burning sensation, labored
breathing; skin burns; contact with liquid causes
frostbite; severe deep burns to eyes; harmful
concentration of this gas in air will be reached very
quickly on loss of containment
Route of Exposure: Inhalation
Use: Manufacture
of nitric acid,
explosives,
synthetic fibers,
and fertilizers.
Chemical Dangers: Shock sensitive compounds are
formed with mercury, silver and gold oxides. The
substance is a strong base; it reacts violently with acid
and is corrosive. Reacts violently with strong oxidants
and halogens. Attacks copper, aluminum, zinc and
their alloys. Dissolves in water evolving heat.
Physical Dangers: The gas is lighter than air.
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UN Classification
Hazard Classes and Divisions
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Class 1
Class 2
Class 3
Class 4
Class 5
Class 6
Class 7
Class 8
• Class 9
Explosives
Compressed Gases
Flammable Liquids
Flammable Solids
Oxidizers
Poisons
Radiological
Corrosives
Other Regulated Materials
NINE HAZARD CLASSES AND SUBDIVISIONS
Class 1 – Explosives
Mass explosion that affects almost the entire load
Class 2 – Gases
NONFLAMMABLE
GAS
FLAMMABLE GAS
2
POISON
GAS
2
2
Class 3 – Flammable Liquids
FLAMMABLE
3
Class 4.1 – Flammable Solids
Flammable
Solid
4
Class 4.2 – Spontaneously
Combustible Materials
SPONTANEOUSLY
COMBUSTIBLE
4
Class 4.3 – Dangerous When Wet
Dangerous
when Wet
4
Class 5.1 – Oxidizers
Oxidizer
5.1
Class 5.2 – Organic Peroxides
Organic
Peroxide
5.2
Class 6.1 – Poison, Inhalation Hazard
Poison
6.1
Class 6.2 – Biohazard
Class 7 – Radioactive
Radioactive
Class 8 – Corrosive
Corrosive
Class 9 - Miscellaneous
Hazardous
Materials
Or
Other Regulated
Materials(ORM)
Aerosol / Infectivity Relationship
The ideal aerosol contains
a homogeneous
population
of 2 or 3 micron
particulates that contain
one or more
viable organisms
Particle Size Infection
(Micron, Mass Severity
Median
Diameter)
18-20
Less
Severe
15-18
7-12
Maximum human
respiratory infection is
a particle that falls
within the 1 to 5
micron size
4-6
(bronchioles)
1-5
(alveoli)
More
Severe
Occupational and environmental
airways diseases
Silicosis
Lake Nyos Volcano
• Lake Nyos was formed due to volcanic eruption
about 400 years ago. It is 5,900 feet across and 682
feet deep.
• Lake Nyos is compositionally stratified with layers
that do not mix, with fresh water in the upper 50
meters and heavier sodium and carbon dioxide
(CO2) rich water below that. It is one of only three
known lakes to be saturated with CO2 in this way.
• Approximately 50 miles below the lake resides a pool
of magma, which charges the water of Lake Nyos
with an estimated 90 million tons of CO2.
• The lake waters are held in place by a natural dam
composed of volcanic rock.
Disaster Strikes
• At 9:30 pm on August 21, 1986 - eruption Lake Nyos
triggered sudden release of 1.6 million tons of CO2..
• The cloud of CO2 rose at nearly 62 miles per hour.
• Carbon dioxide, 1.5 times as dense as air, cloud hug the
ground and descend down the valley. The 164 ft thick
cloud traveled downward at a rate of 12-31 mph.
• killed over 1700 people, thousands of cattle, birds and
animals.
• The bodies of those that died were generally devoid of
trauma, suddenly fallen asleep and died from
asphyxiation.
• Following the disaster, the lake was dubbed the “Deadliest
Lake” by the Guinness World Records in 2008.
The Science Behind the Disaster
• It is important to remember that Lake Nyos is thermally
stratified- with layers of warm, less dense water near the surface
floating on the colder, denser waters near the lake’s bottom.
• Over time, the lowest levels of the lake become more and more
saturated with gas. And eventually, when they reach 100%
saturation, the CO2 rich gas can bubble spontaneously out of the
lake , creating a foaming column of carbonated water.
•
This eruption can be triggered by an event such as a landslide,
earthquake, violent storm, or other disturbance of the water.
• The normal blue waters of the lake turned a deep red after the
outgassing, due to iron-rich water from the deep rising to the
surface and becoming oxidized by the air.
• The level of the lake dropped about a meter, representing the
volume of gas released
Tin:
allotropic forms:
-Sn
“grey tin”
-Sn
13.2°C “white tin” 161°C -Sn 232°C Sn(l)
-Sn:
typical metallic properties: conductor, ductile
crystal structure: body centered tetragonal
d = 7.29 g/cm3
-Sn : semiconductor, non-ductile
crystal structure: diamond cubic
d = 5.77 g/cm3
Tin Pest (tin disease, tin plague, devil´s disease):
first reported: 1851; responsible for the disintegration of tin dishes,
organ pipes, …
is the product of the conversion: -Sn  -Sn at T < 13.2 °C
volume change leads to the total disintegration of the sample
Tin Pest
without tin pest
complete disintegrated
All for want of a button
Tin has two allotropic forms : α (gray tin )  β (white tin)
White tin is shiny metal and stable at room temperature
but slowly transforms into gray tin below 13 oC. This
weakens the metal and makes it crumble (tin disease).
In June 1812, Napoleon’s mighty army, some 600,000
strong marched into Russia, but by early December his
forces were reduced to fewer than 10,000 men. An
intriguing theory for Napoleon’s defeat has to do with
tin buttons on his soldiers’ coats! The soldiers were
probably more busy holding their coats together with
their hands than carrying weapons.
Mars Surveyor Program 1999
Mars Climate Orbiter
Mars Polar Lander
Mars Surveyor Program 1999 (Orbiter and Lander)
• Mission: To study Martian weather, climate,
atmosphere, evidence of life, …
– $327.6 million total
– MCO lost due to navigation error
• Launch Dec 11, 1998 – Lost Sep 23, 1999
• Failure is attributed to the failure of NASA’s system
engineering process. The process did not specify the
system of measurements to be used in the project (English
vs. Metric)
– MPL never called home!
• Launch Jan 3, 1999 – Lost: Dec 3, 1999
Mars Surveyor Program 1999 (Orbiter and Lander)
In December 1998 NASA launched the 125 Million$ Mars climate
Orbiter. After 416 Million mile jorney, the space craft was
supposed to go into Mars’ orbit on Sept. 23, 1999. Instead it
entered Mars’ atmosphere about 100 km (62 Mile) lower than
planned and was destroyed by heat.
The error occurred due to the failure to convert English
Measurement units into metric unit.
Engineers at Lockheed Martin Corporation who built the spacecraft
specified its thrust in pounds. Scientists at NASA,s Jet Propulsion
Laboratory, on the other hand assumed that thrust data they
received were in metric units, as Newton.
Conversion between Pound and Newton
1 Pound is the force due to gravitational attraction on an object of
that mass. 1 lb = 0.4536 kg,
from Newton’s second law : force = mass x accelaration
= 0.4536 kg x 9.81 m/s2
= 4.45 kg. m/s2
= 4.45 N
Because 1 N = 1 kg m/s2, instead of converting one pound of force
to 4.45 N, the scientists treated it as 1 N.
this considerable small thrust resulted in a lower orbit and the
ultimate destruction of the spacecraft.
The Patriot Missile Failure
• February 25, 1991 – Gulf War – Dharan, Saudi
Arabia
• American Patriot Missile battery failed to track
and intercept an incoming Iraqi Scud missile
– 28 US soldiers killed, 100+ injured
• Software bug: inaccurate calculation of the time
since boot due to computer arithmetic errors
Minamata, Japan Mercury Poisoning
Disaster
• The Minamata Disaster was
more of an on going mass
poisoning than a single
catastrophe.
– It was caused by the Chisso
Corparation in the city of
Minamata on Kyushu Island,
Japan.
– They dumped organic
mercury off the coast of
Minamata for over 3 decades.
– There have been over 3,000
victims. Many of them lost
their lives and others suffered
from physical deformities.
http://wi.water.usgs.gov/pubs/FS-216-95/mercury.pg3.pdf
• Bioaccumulation occurs when
an organism takes up
contaminants more quickly that it
eliminates them
• Biomagnification is an
incremental increase in the
concentration of a contaminant at
each level of the food chain
http://wi.water.usgs.gov/pubs/FS-216-95/mercury.pg2.pdf
Disaster Continued
• Chisso knew the mercury they
were dumping was contaminating
the water, but did nothing.
– The poisoned waters created a
ripple effect; killing marine life,
birds, domestic animals and
humans.
– Villagers that complained were
measly compensated or
threatened.
• The Chisso Corporation stopped
poisoning the waters in 1968 only
when the method of mercury
production became outdated.
Signs and Symptoms
• Victims were diagnosed
with a degenerative
nerve condition.
• Signs included:
– Numbness of the limbs and lips
– Slurred speech and blurred
vision
– Brain damage
– Loss of consciousness
– Involuntary movements
– Symptoms of Turrets Syndrome
(uncontrolled shouting)
– Physical Deformities
Images Continued
BHOPAL DISASTER
Total breakdown of essential safety provisions and negligence of the authorities
 According to safety norms MIC tanks should be protected by dry Nitrogen
blanket and kept at 0 oC by refrigeration.
 Refrigeration unit was shut down since June 1984, gas was at 15-20 oC.
 MIC reacts violently with water and also undergoes polumerisation in
presence of catalysts like Fe, Cu, Zn (both processes highly exothermic)
 MIC is always associated with 2% Phosgene (TLV 0.1 ppm)
 Leakage detected at 11.30 p.m., Temperature gauge showed 25 oC, pressure
build up above 55 psi and the safety valve opened.
 MIC gushed out from 120 ft. high stack, water jet failed to reach that height,
vent gas scrubber which neutralizes MIC with caustic soda was out of order.
 Factory turned on the public siren at 1 am for a few minutes only, people got
up not due to siren but due to irritation caused by gas.
 For about two hours the safety valve remained open and then reseated as the
tank pressure dropped below 40 psi.
Advent of a new age
 20th March 1995
 Tokyo Metrorail
 Morning rush hour between 8.09 - 8.13 a.m.
 Radical group ‘AUM SHINRIKYO’ placed five plastic
pouches of lethal nerve agent SARIN and punctured
them
 11 immediate deaths and 5500 injured
 More than 26 stations closed for three weeks [Aum
Shinrikyo was also in possession of germs Yersinia Pestis
which causes Plaque and large stockpile of SARIN]
Tokyo Chemical Incident
20 March 1995: Sarin
attack in Tokyo by the
Aum Shinrikyo
Some useful chemicals may be abused!
• Ammonium nitrate most important fertilizer
in the world is ranked 15th among industrial
chemicals produced.
• UNFORTUNATELY IT IS A POWERFUL
EXPLOSIVE!
Phosgene
• At high concentrations:
– Irritates eyes, nose, upper airways; possible laryngospasm
• Toxic to lungs by inhalation
• Carbonyl group damages alveolar-capillary
membrane
• Non-cardiac pulmonary edema: onset 2 to 12 hours
– Dyspnea, cough with sputum
Cl
C=O
• Management of non-cardiac pulmonary edema
– Hypoxia, fluid loss; requires pulmonary care, careful fluid
replacement
• ABSOLUTE REST POST-EXPOSURE
Cl
Nerve Agent
Medical Treatment
• Atropine
– Dries secretions; relaxes smooth muscles
– Given IV, IM, ET
• No effect on pupils
• No effect on skeletal muscles
Nerve Agent
Treatment
• Starting dose - 2 mg
• Maximum cumulative dose - 20 – 30 mg
– Insecticide poisoning requires much more
• Side effects in normal people
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–
–
–
Mydriasis
Blurred vision
Tachycardia
Decreased secretions and sweating
Nerve Agent
Medical Treatment
• Atropine - How much to give?
– Until secretions are drying or dry
– Until ventilation is “easy”
– Do not rely on heart rate or pupil size
Nerve Agent
Medical Treatment
• Pralidoxime Chloride (2PAM-Cl)
– Remove nerve agent from AChE
– 1 gram slowly (20-30 minutes) in IV infusion
• Hypertension with
rapid infusion
Nerve Agent
– No effects on
glands, smooth muscle
AChE
2-PAMCl
Any Questions
CAUSES OF DISASTERS
HUMAN FACTORS : The causes of failure can be classified as:
Insufficient knowledge
Underestimation of influence
Ignorance, Carelessness, negligence
Forgetfulness, error
Relying upon others without sufficient control
Nonprecise definition of responsibilities
Bad quality
Other
36 %
16 %
14 %
13 %
9%
1%
1%
3%
FACTORS AFFECTING CW
• AIR MOVEMENT
• TEMPERATURE
• COLD WEATHER
• RAIN AND HUMIDITY
• TERRAIN
NERVE AGENTS - ANTODOTES &
TREATMENT AFTER EXPOSURE
• 4 Steps to management
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•
•
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Decontamination
Ventilation
Antidotes
Supportive therapy
• Atropine and
pralidoxime chloride
(autoinjectors provided)
• Diazepam
(anticonvulsant drug)
HARASSING AGENTS ANTIDOTES & TREATMENT
• Relocate to fresh air
• Through washing of exposed eyes and skin
with water
• Effects gradually dissipate within 15-30
minutes of departure from contaminated area
PROTECTION AGAINST CW
• Use respirator
• Whole body should be protected with
suitable anti-gas clothing
• In the absence of proper respirator breathing
through a towel of large handkerchief
saturated with alkaline solution gives a certain
degree of protection