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653
June-3- pmd
J. Indian Chem. Soc.,
Vol. 94, June 2017, pp. 653-656
Accidental fire due to spray of pesticide in a household
Gargi Bhattacharjeea, Susmita Neogib and Sudip Kumar Dasa
aChemical Engineering Department, bDepartment of Home Science,
University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata-700 009, India
E-mail : drsudipkdas@vsnl.net
Manuscript received 22 February 2017, accepted 15 March 2017
Abstract : On 13th May 2011 in Pune, India an aerosol insect repellents can exploded in kitchen of a house.
The lady processing foods in a gas stove in her kitchen and found some cockroaches near the sink and grabbed
a can of insect repellent and sprayed it near the burning gas stove. The flammable aerosol compound propel-
lant came in contact with the flame of the burning stove and it made the explosion. This paper deals the prob-
able causes of the case study and finally some useful general recommendations are discussed.
Keywords : Aerosol, pesticides, flammable, LPG, propellant.
Introduction
Aerosols are increasingly used in household dwell-
ings. Aerosols spray cans are used in many commodi-
ties like pesticides, insect killers, hair sprays, deodor-
ants, air fresheners, oven cleaners, tile cleaners, fur-
niture polishes etc. Many people use these products
without realizing some of the potential hazards associ-
ated with them. In general, it incorporates propellant,
in the range of 20% to 95% of the contents and is
packed under pressure in the form of liquid. When the
nozzle of an aerosol is pressed, the product and pro-
pellant are released from the container in the form of
a fine mist. Some of aerosol products can be corro-
sive, flammable or poisonous. Aerosol contains large
quantities of propellants often they are flammable, hence
hazardous. The LEL and UEL (lower and upper ex-
plosive limits) for the common propellants are as shown
below (Table 1).
In general the auto ignition temperatures of the pro-
pellant vary from 350 ºC for dimethyl ether (DME) to
505 ºC for propane, whereas the temperature of an
idly burning cigarette is over 540 ºC. Boiling points
of liquefied gas aerosol propellants varies in the range
from –42 ºC to +0.6 ºC. The vapor pressures of liq-
uefied gas aerosol propellants range from 1.25 atmg to
7.5 atmg at room temperature, i.e. 25 ºC but as the
temperature increases the pressure also increases, i.e.
2.5 atmg to 12 atmg at 40 ºC. During nozzle pressing
the product pressure inside the container can be con-
siderably higher. The common pressure related haz-
ard associated with it is the possible aerosol container
rupture. Exposure to liquefied gas aerosol propellants
on human can cause severe irritation, redness, tear-
ing, blurred vision and possibility of freeze burn if it
comes in contact with eyes and in the case of skin
contact there is possibility of severe frostbite depend-
ing upon the propellant composition. In general the
poisonous symptoms of human health are nervousness,
anxiety, tremors and allergic manifestations. Acute
symptoms of aerosol exposure include headache, nau-
sea, dizziness, shortness of breath, throat irritation and
skin rash and explosion of aerosol products can cause
burn and death.
Ames and Crowhurst1 reported a total of 297 inci-
Table 1.
The LEL and UEL for the common propellants
Propellant LEL UEL
Propane 2.2 9.5
Isobutane 1.8 8.4
n-Butane 1.9 8.5
Dimethyl ether (DME) 3.4 18.0
Dymell 52a 3.9 16.9
134a Non-flammable
654
dents of domestic dwellings in 1982-1984 where LPG
is used as propellant. They examined six incidents in
detailed, all cases small quantities of LPG used as
propellant in the aerosol products. They observed that
the LPG released due to overheating and in one case
vapour released due to mechanical puncturing. In all
cases LPG involved was less than 200 g and the small-
est was 30 g. They reported the explosion condition as
shown below (Table 2). They also concluded that no
attempt was made to correlate the damage caused with
the amount of LPG present. They experimentally stimu-
lated these types of incidents where amount of LPG
involved less than 500 g and observed that the pres-
sure developed in the range of 14–42 kPa in a domes-
tic room which would cause the severe damage in the
room and also injured people. Scerri et al.2 reported
the burns injury for seven people associated with bu-
tane cigarette lighter fluid abuse when a group of people
sitting within an enclosed space. Yarbrough3 reported
that 5% to 45% body surface burn of 18 people in 5
years span affected in the explosion of pressurized
aerosol can.
In general aerosol cans contain two different sub-
stances, the liquid product which in releasing (the paint,
detergent, hairspray, insecticide etc.) and a pressu-
rized gas called a propellant that helps to push the
liquid product into the air and turn it into an aerosol
cloud. The propellant gas usually turns into a liquid
when it’s forced inside the can at high pressure during
manufacturing. That makes the propellant and the pro-
duct mix together. The propellant turns back to a gas
when pushing the nozzle and the pressure is released.
Pesticides aerosol can
Pesticide is a general term used to describe a sub-
stance or mixture that kills a pest or it prevents or
reduces the damage a pest may cause. Pests can be
insects, mice or other animals, unwanted plants (weeds),
fungi, bacteria or viruses. Pesticides are formulated in
liquid, solid and gaseous forms. Pesticides can be clas-
sified by target organism, chemical structure, and physi-
cal state. In every day normally we used the common
categories of pesticides which are insecticides which
kills or repel insects, herbicides which kills weeds or
unwanted plants, fungicides which kills mould, mil-
dew and other fungi, rodenticides which kills mice
and rats, disinfectants kills bacteria, mould and mil-
dew and wood preservatives which protects wood from
insects and fungi. Pesticides are often grouped into
“families” because they share similar chemical pro-
perties, or they act on the pest in the same way. Promi-
nent insecticide families include organochlorines, or-
ganophosphates and carbamares. Pesticides also can
be classified based upon their biological mechanism
function or application method. Most pesticides work
by poisoning pests.
Although pesticides are designed to kill pests but
some pesticides are harmful for humans. The health
Table 2.
Products involved in aerosol explosion conditions
(Ames and Crowhurst, 1988)
Incident Product Can volume Estimated LPG Cause of Ignition source Category of
No. (ml) content (g) leakage of LPG explosion
1. Aerosol air freshener 200 30 Overheating by Fire in radio/ Severe
small accidental fire cassette
2. Aerosol paint spray 400 50 Overheating by Gas cooker Severe
by gas cooker
3. Aerosol air freshener 300 150 Overheating by Fan heater Severe
electrical fan
4. Aerosol air freshener 200 180 Overheating by small Candle flame Severe
accidental fire and small fire
5. Aerosol hair spray 440 60 Can punctured Gas fire Moderate
with scissors
6. Aerosol air freshener 225 200 Fire Fire Severe
Bhattacharjee et al. : Accidental fire due to spray of pesticide in a household
655
effect depends on the type of pesticides and other chemi-
cals that are in the using product. Most often pesti-
cides affect the nervous system and also effects from
acute (short-term) exposure or poisonings are shown
in following (Table 3). Some spray pesticides are flam-
mable, so used should be carefully. One of the com-
monly used mosquitoes repellant in India is Hit, Mortein
etc. The probable composition of Hit mosquito repel-
lent (Batch No. B-E11109F088) is shown in Table 4.
lady processing foods in a gas stove in her kitchen
found some cockroaches near the sink and grabbed a
can of insect repellent and sprayed it near the burning
gas stove. There was an explosion and the poor woman
was covered in flames, sustaining 65% burns. Her
husband tried to rescue her but he was also injured
due to the burns and was hospitalized and the house
wife was declared dead.
Probable causes
All insect repellents such as Hit, Mortein etc. are
most popular in India, have highly volatile inflam-
mable propellant. The propellants are chosen by the
manufacturer for the characteristics that they provide
for discharge of the base product. Over the past de-
cade the chlorofluorocarbon propellant commonly used
in aerosol cans has been replaced with hydrocarbon
blends that include propane, butane, and isobutane. At
present the propellant is mainly LPG in the aerosol
mixture with the active ingredients. In the spray con-
dition the aerosol mist can ignite to form an explosion
mixture with oxygen present in air and this explosion
can be achieved by only one spark. The house wife
used the aerosol insect repellent near the burning gas
stove. The flammable aerosol compound propellant
came in contact with the flame of the burning stove
and it made the explosion. Initially the LPG caught
fire and the fire transmitted to the can. The ignite gas
inside expands the container ruptures. This gas ignites
causing an explosion. This situation is similar as
BLEVE (Boiling Liquid Expanding Vapour Explosion).
Recommendations
(1) An aerosol can should be in compliance with
international and national safety standards, like Aus-
tralian Standard AS 2278 (Metal Aerosol Containers),
Table 4.
Probable composition of insecticides Hit (mosquito
repellents)
Composition Amount (%, w/w)
d-trans Allethrin a.i. 0.25
Synergist (PBO) 0.50
Perfume 0.20
Deodorised kerosene 39.05
Propellant gas (LPG) 60.00
Total 100
Table 3.
Some general symptoms from pesticide poisoning
Mild poisoning Moderate poisoning Severe poisoning
Mild and moderate symptoms and inabi-
lity to breathe, extra phlegm or mucous
in the airways, small or pinpoint pupils,
chemical burns on the skin, increased rate
of breathing, loss of reflexes, uncontrol-
lable muscular twitching, unconsciousness
death.
Mild symptoms and vomiting, exces-
sive salivation, coughing, abdominal
cramps, blurring of vision, rapid pulse,
excessive perspiration, profound weak-
ness, trembling, muscular in coordina-
tion, mental confusion.
Irritation of the nose, throat, eyes
or skin, headache, dizziness, loss
of appetite, thirst, nausea, diarrhea,
sweating, weakness or fatigue, rest-
lessness, nervousness, changes in
mood, insomnia.
The aerosol container is a high-strength metal unit
consists of a valve, whose various openings control
how much products be comes out, how fast and whether
it is a spray, foam or gel, an actuator, on pressing it
opens the valve, a dip tube, on pressing the actuator
the valve is opened, the product comes up through the
dip tube. The can in general a airtight metal container
has a designed bottom and top to add strength. An
aerosal contain propellant, a compound that exerts pres-
sure and helps dissolve the product as it carries it out
of the can. The ingrediants like soap or disinfectants
or water that dissolve, dispense, and stabilize the pro-
duct.
The incident
4
On 13th May 2011 in Pune, India an aerosol insect
repellents can exploded in kitchen of a house. The
656
USA Code Federal Regulations, Title 49 Part 173.306
and Part 178.33 etc.
(2) If there are any changes in the physical prop-
erty of the can or its contents, i.e. active ingredients
or propellants, then retest must be conducted to ensure
compliance of the safety norms.
(3) One should comply with the warning labels of
aerosol can. Recognized safety standards should be
printed in English and local languages. It should in-
clude following instructions;
(i) A warning that the contents include LPG as
propellant;
(ii) Can should not be used near any naked flame;
(iii) Can should only be used in well ventilated
area and should not be directed at any electri-
cal appliances in operation;
(iv) The can should be kept in safe storage re-
quirements like out of reach of children and
well ventilated dry place;
(v) If it falls on skin then skin should be washed
with adequate water and then soap;
(vi) If eyes are affected, water should be splashed
on eyes;
(4) Safe disposal techniques – In general cans are
made of steel/aluminium can be recycled. For recy-
cling the can should be completely empty and also the
pressure relief valve should be removed.
(5) When using some general aerosol products one
(i) Should check the aerosol can for damage and
leaks;
(ii) Keep the container in a dry, cool and well
ventilated place;
(iii) Should not make an excessive use of aerosol
can;
(iv) Should not inhale the contents of the aerosol
can;
(v) Should not refill the aerosol can;
(vi) Should not puncture or burn the used aerosol
can;
(vii) Keep the aerosol can in an enclosed space.
Conclusion
This study reported an accidental case study due to
spray of pesticide in kitchen. Due to lack of knowl-
edge the house wife used the aerosol insect repellent
near the burning gas stove and the flammable aerosol
compound propellant came in contact with the flame
of the burning stove and it made the explosion. Finally
some useful general recommendations are discussed.
References
1. S. Ames and D. Crowhurst,
J. Hazard. Mater.
, 1988,
29
, 183.
2. G. V. Scerri, P. J. Regan, R. J. Ratcliffe and A. H. N.
Roberts,
Burns
, 1993,
18
, 329.
3. D. R. Yarbrough,
Burns
, 1998,
24
, 220.
4. The Times of India, 14th May, 2011.