Union Carbide India Ltd.
UCIL was the Indian
subsidiary of Union
Carbide Corporation (UCC).
controlled banks and the
Indian public held 49.1%
In 1994, the Supreme Court
of India allowed UCC to sell
its 50.9 percent share. The
Bhopal plant was sold to
McLeod Russel (India) Ltd.
UCC was purchased by Dow
Chemical Company in 2001.
Location of the plant…
In close vicinity of the
What caused the gas leak?
An initial investigation by Union Carbide experts showed
that a large volume of water had apparently been
introduced into the methyl isocyanate (MIC) tank.
This caused a chemical reaction that forced the pressure
release valve to open and allowed the gas to leak.
A committee of experts working on behalf of the Indian
government conducted its own investigation and reached
the same conclusion.
An independent investigation by engineering consulting firm
Arthur D. Little determined that the water could only have
been introduced into the tank deliberately, since process
safety systems -- in place and operational -- would have
prevented water from entering the tank by accident.
Leakage & it’s immediate
In November 1984, most
of the safety systems
were not functioning and
many valves and lines
were in poor condition.
In addition to this,
several vent gas
scrubbers had been out
of service as well as the
steam boiler, intended
to clean the pipes was
When water entered the tank no.610 containing about 42 tons
of MIC . A runaway reaction started, which was accelerated by
contaminants, high temperatures and other factors.
The reaction was sped up by the presence of iron from
corroding non-stainless steel pipelines.
The resulting exothermic reaction increased the temperature
inside the tank to over 200 °C (392 °F) and raised the
This forced the emergency venting of pressure from the MIC
holding tank, releasing a large volume of toxic gases.
About 30 metric tons of methyl isocyanate (MIC) escaped
from the tank into the atmosphere in 45 to 60 minutes.
Why didn’t the plant’s
safety systems contain the
Based on several investigations, the safety systems in place
could not have prevented a chemical reaction of this
magnitude from causing a leak. In designing the plant's
safety systems, a chemical reaction of this magnitude was
not factored in for two reasons:
1. The tank's gas storage system was designed to
automatically prevent such a large amount of water from
being inadvertently introduced into the system; and
2. Process safety systems -- in place and operational --
would have prevented water from entering the tank by
accident. ”The system design did not, however, account for
the deliberate introduction of a large volume of water by
The gas cloud
The gases were blown in south eastern direction over
As of 2008, UCC had not released information about the
possible composition of the cloud. Apart from MIC, the
gas cloud may have contained phosgene, hydrogen cynide,
carbon monoxide, hydrogen chloride, oxides of nitrogen,
mono methyl amine (MMA) and carbon dioxide, either
produced in the storage tank or in the atmosphere.
The gas cloud was composed mainly of materials denser
than the surrounding air, stayed close to the ground and
spread outwards through the surrounding community.
The nature of the cloud is still discussed. The chemical
reactions would have produced a liquid or solid aerosol
with high density.
The concentrations at ground level would have been much
higher than earlier published.
Reversible reaction of glutathione (top) with methyl
isocyanate (MIC, middle) allows the MIC to be
transported into the body
Hydrogen cyanide debate
Whether hydrogen cyanide(HCN) was present in the gas
mixture is still a controversy.
Cyanide concentrations of 300 ppm can lead to immediate
The non-toxic antidote sodium thiosulfate (Na2S2O3) in
intravenous injections increases the rate of conversion
from cyanide to non-toxic thio cynate.
Initial reports based on the autopsies of victims' bodies
suggested cyanide poisoning based on which UCC's Dr. Bipan
Avashia advised amyl nitrate and sodium thiosulphate.
Treatment was tentatively used on some people, with mixed
Critics argue that both the Government and Union Carbide
tried to avoid mentioning the emotionally provocative word
Exposed to high temperatures, MIC breaks down to
hydrogen cyanide (HCN).
According to Kulling and Lorin, at +200 °C, 3% of the gas is
HCN. However, according to another scientific
publication ,MIC when heated in the gas-phase starts to
break down to hydrogen cyanide (HCN) and other products
above 400 °C.
Chemically, HCN is known to be very reactive with MIC.
HCN is also known to react with hydrochloric acid, ammonia,
and methylamine (also produced in tank 610 during the
vigorous reaction with water and chloroform) and also with
itself under acidic conditions to form trimers of HCN called
Laboratory replication studies by CSIR and UCC scientists
failed to detect any HCN or HCN-derived side products.
None of the HCN-derived side products were
detected in the tank residue.
UNION CARBIDE’S VERSION
“ A disgruntled plant employee, apparently bent on
spoiling a batch of methyl isocyanate, added
water to a storage tank”.
-------B. Browning Jackson
In order to provide safe drinking water to the population
around the UCIL factory, Government of Madhya Pradesh
presented a scheme for improvement of water supply.
In December 2008, the Madhya Pradesh High Court decided
that the toxic waste should be incinerated at Ankleshwar in
Gujarat, which was met by protests from activists all over
India.[ On 8 June 2012, the Centre for incineration of toxic
Bhopal waste agreed to pay 250 million (US$4.0 million) to
dispose of UCIL chemical plants waste in Germany . On 9 August
2012, Supreme court directed the Union and Madhya Pradesh
Governments to, take immediate steps for disposal of toxic
waste lying around and inside the factory within six-month.
A US court rejected the law suit blaming UCC for
causing soil and water pollution around the site of the
plant and ruled that responsibility for remedial
measures or related claims rested with the State
Government and not with UCC.
In 2005, the state government invited various Indian
architects to enter their "concept for development of
a memorial complex for Bhopal gas tragedy victims at
the site of Union Carbide". In 2011, a conference was
held on the site, with participants from European
universities which was aimed for the same.
There are no words for this…
The testimony of a Bhopal
”I used to pick up unclaimed dead bodies from the
mortuary, I was used to doing it. That night (3rd
December 1984) I put in thousands of bodies that we
dumped - in one grave we would put 5-6 bodies, and
we burnt piles and piles with logs. Many bodies were
burnt un indentified - Muslims were burnt and Hindus
We would fit 120 bodies in one truck and this we would
fill and empty five times a day. There were eight
trucks on duty (so that is 4,800 bodies a day). It
carried on for exactly the same intensity for three
to four days, the bodies had all turned blue…..
"At least 15 - 20,000 people died in those first few days.
What they said in the papers was absolutely wrong. What
could I have done? I was a government servant. What the
government said was absolutely wrong…. but ,what could I
The continuing medical
nightmare of Carbide's
From what do the gas survivors in Bhopal suffer? In
the districts near the factory, people are wracked by
breathlessness, blurred vision, aching limbs and
backs; numb limbs; there are monstrous births;
children suffer from recurrent fevers and coughs;
even young adults are developing cataracts and feel
constantly exhausted, with no appetite either for
food or for life; Carbide's gases have added
anxiety to their already hard lives.
The continuing medical
nightmare of Carbide's
It’s estimate that there
are between 120,000 to
150,000 people still ill in
Bhopal ie. suffering from
conditions which in many
cases do not permit them
to work, so they are
wretchedly underfed and
this further exacerbates
their health problems.
The continuing medical nightmare
of Carbide's victims….
The people living near the abandoned factory - where
piles of dangerous chemicals lie in the open air to this
day are obliged to drink water heavily polluted with
Sevin residues, 12 volatile organic chemicals, heavy
metals and mercury millions of times higher than
recognized safety limits.
The water makes people ill, with the same kind of
symptoms as those who had been exposed to the gas
in 1984. Here too, the death toll is high. And the real
pollution feeding the local aquifers lies under the
ground, where around a thousand tonnes of numerous
chemicals were routinely dumped during normal
operations at the factory prior to the gas leak.
What caused this disaster….
1] Factory Siting
A plant producing a variety of very dangerous
compounds was sited:
a) too close to a residential area
b) on the wrong side with respect to the prevailing
2] Large Product Inventory
Total storage capacity of MIC was in excess of 150 m3
When dealing with such toxic products, the amount at
hand should always be minimized.
3] Abandonment of Safeguards
Economic problems and the resultant pressure to save
money lead to the shutting down of vital safety systems.
If the factory was uneconomic it would have proved a
more sensible option to shut it down.
4] Medical Unpreparedness
Not enough information on the toxicity of the factory’s
products and lack of knowledge of treatment in the local
hospitals. The factory should have been much more pro-
active in liasing with the municipal authorities in
preparing an emergency evacuation plan.
DISASTER BECAUSE OF
Bhopal is not only a disaster,
but a corporate crime.
It began as a classic instance of
Union Carbide was obliged to
technology in Bhopal, but
instead used inferior and
unproven technology and
employed lax operating
procedures and maintenance
and safety standards compared
to those used in its US 'sister-
DISASTER BECAUSE OF
On December 25, 1981, a leak of phosgene killed one
worker, Ashraf Khan, at the plant and severely injured
On January 9, 1982, twenty five workers were
hospitalized as a result of another leak at the plant.
Yet another leak on October 5, 1982 affected
hundreds of nearby residents requiring hospitalization
of large numbers of people residing in the
communities surrounding the plant, which included
quantities of MIC, hydrochloric acid and chloroform.
“Operation Faith”: On December 16, the tanks 611
and 619 were emptied of the remaining MIC. This
led to a second mass evacuation from Bhopal.
2,000 bloated animal carcasses had to be
Doctors and hospitals were not informed of proper treatment
methods for MIC gas inhalation.
They were told to simply give cough medicine and eye drops to
As against a billion-dollar compensation in demand, in
1989, the Supreme Court brokered an out-of-court
settlement between the Indian government and the
Union Carbide - a full and final settlement of 470
million dollars, absolving the Union Carbide of all
criminal and civil liabilities.
Even the statistics of the injured and the dead were
The 470-million dollar compensation was meant for only
one lakh and eight thousand victims, quoted at that
time by the government despite wide spread protest
against this underestimation.
Eventually, the number
of those affected was
increased to nearly six
lakh. But the
was not, so each victim
got far less than they
should have and there
are many who did not
even get a single
THE STRUGGLE FOR JUSTICE….
Civil and criminal cases are pending in the United
States District Court, Manhattan and the District
Court of Bhopal, India, involving UCC, UCIL employees,
and Warren Anderson, UCC CEO at the time of the
In June 2010, seven ex-employees, including the former
UCIL chairman, were convicted in Bhopal of causing
death by negligence and sentenced to two years
imprisonment and a fine of about $2,000 each, the
maximum punishment allowed by law. An eighth former
employee was also convicted but died before judgment
The disaster did pave the way for much stricter international
standards for environmental safety, preventative strategies to
avoid similar accidents and a better state of preparedness to
meet future industrial disaster. In India, a number of changes
were made in the Indian Factories Act and environmental
There is a much better understanding of the fact that industries
need to apply good process safety management systems and have
efficient and safe handling and storage capacities of individual
Following the disaster, environmental awareness and activism in
India has increased tremendously. It serves as a warning to
developing nations to create the right balance between human,
environmental and economic status on the path to
On the twenty-fifth
anniversary of the Bhopal
disaster, a coalition of labor
and environmental groups put
out a call for safety at U.S.
The House of Representatives
approved a compromise
chemical security bill (H.R.
2868) that could help
catastrophes at some the
highest risk U.S. chemical