IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
Health and Safety Guide No. 90
ACETALDEHYDE
HEALTH AND SAFETY GUIDE
UNITED NATIONS ENVIRONMENT PROGRAMME
INTERNATIONAL LABOUR ORGANISATION
WORLD HEALTH ORGANIZATION
WORLD HEALTH ORGANIZATION, GENEVA 1994
This is a companion volume to Environmental Health Criteria
167: Acetaldehyde
Published by the World Health Organization for the International
Programme on Chemical Safety (a collaborative programme of the
United Nations Environment Programme, the International Labour
Organisation, and the World Health Organization)
This report contains the collective views of an international group
of experts and does not necessarily represent the decisions or the
stated policy of the United Nations Environment Programme, the
International Labour Organisation, or the World Health Organization
WHO Library Cataloguing in Publication Data
Acetaldehyde : health and safety guide.
(Health and safety guide ; no. 90)
1.Acetaldehyde - adverse effects 2.Acetaldehyde - toxicity
3.Environmental exposure I.Series
ISBN 92 4 151090 0 (NLM Classification: QU 99)
ISSN 0259-7268
The World Health Organization welcomes requests for permission to
reproduce or translate its publications, in part or in full.
Applications and enquiries should be addressed to the Office of
Publications, World Health Organization, Geneva, Switzerland, which
will be glad to provide the latest information on any changes made
to the text, plans for new editions, and reprints and translations
already available.
(c) World Health Organization 1994
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CONTENTS
INTRODUCTION
1. PRODUCT IDENTITY AND USES
1.1. Identity
1.2. Physical and chemical properties
1.3. Composition
1.4. Analysis
1.5. Production and uses
2. SUMMARY
2.1. Identity, physical and chemical properties, and
analytical methods
2.2. Sources of human and environmental exposure
2.3. Environmental transport, distribution, and
transformation
2.4. Environmental levels and human exposure
2.5. Kinetics and metabolism
2.5.1. Absorption, distribution, and elimination
2.5.2. Metabolism
2.5.3. Reaction with other components
2.6. Effects on organisms in the environment
2.6.1. Aquatic organisms
2.6.2. Terrestrial organisms
2.7. Effects on experimental animals and in vitro
test systems
2.7.1. Single exposure
2.7.2. Short- and long-term exposures
2.7.3. Reproduction, embryotoxocity, and
teratogenicity
2.7.4. Mutagenicity and related end-points
2.7.5. Carcinogenicity
2.7.6. Special studies
2.8. Effects on humans
3. EVALUATION AND CONCLUSIONS
4. HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION, EMERGENCY
ACTION
4.1. Human health hazards, prevention and
protection, first aid
4.2. Advice to physicians
4.3. Health surveillance advice
4.4. Explosion and fire hazards, prevention
4.4.1. Explosion and fire hazards
4.4.2. Prevention
4.4.3. Fire extinguishing agents
4.5. Storage
4.6. Transport
4.7. Spillage
5. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION
6. SUMMARY OF CHEMICAL SAFETY INFORMATION
7. CURRENT REGULATIONS, GUIDELINES, AND
STANDARDS
7.1. Exposure limits
7.2. Specific restrictions
7.3. Labelling, packaging, and transport
7.4. Discharges, waste disposal
BIBLIOGRAPHY
INTRODUCTION
The Environmental Health Criteria (EHC) monographs produced by the
International Programme on Chemical Safety include an assessment of
the effects on the environment and on human health of exposure to a
chemical or combination of chemicals, or physical or biological
agents. They also provide guidelines for setting exposure limits.
The purpose of a Health and Safety Guide is to facilitate the
application of these guidelines in national chemical safety
programmes. The first three sections of a Health and Safety Guide
highlight the relevant technical information in the corresponding
EHC. Section 4 includes advice on preventive and protective measures
and emergency action; health workers should be thoroughly familiar
with the medical information to ensure that they can act efficiently
in an emergency. Within the Guide is a Summary of Chemical Safety
Information which should be readily available, and should be clearly
explained, to all who could come into contact with the chemical. The
section on regulatory information has been extracted from the legal
file of the International Register of Potentially Toxic Chemicals
(IRPTC) and from other United Nations sources.
The target readership includes occupational health services, those
in ministries, governmental agencies, industry, and trade unions who
are involved in the safe use of chemicals and the avoidance of
environmental health hazards, and those wanting more information on
this topic. An attempt has been made to use only terms that will be
familiar to the intended user. However, sections 1 and 2 inevitably
contain some technical terms. A bibliography has been included for
readers who require further background information.
Revision of the information in this Guide will take place in due
course, and the eventual aim is to use standardized terminology.
Comments on any difficulties encountered in using the Guide would be
very helpful and should be addressed to:
The Director
International Programme on Chemical Safety
World Health Organization
1211 Geneva 27
Switzerland
1. PRODUCT IDENTITY AND USES
1.1 Identity
Chemical formula: C2H4O
Chemical structure:
H
'
H - C - C = O
' '
H H
Common name: acetaldehyde
Common synomyms: acetic aldehyde, acetylaldehyde, ethanal,
ethylaldehyde, diethyl acetal, 1,1-diethoxy
ethane
CAS registry number: 75-07-0
RTECS registry number: AB 1925000
Conversion factors: 1 ppm acetaldehyde =
1.8 mg acetaldehyde/m3 air
1 mg acetaldehyde/m3 air =
0.56 ppm acetaldehyde
at 25 °C and 101.3 kPa (760 mmHg).
1.2 Physical and Chemical Properties
Acetaldehyde is a mobile liquid with a pungent suffocating odour
that is somewhat fruity and pleasant in dilute concentrations. The
odour threshold for acetaldehyde in air is reported to be 0.09
mg/m3 (0.05 ppm).
The compound is miscible in all proportions with water and most
common organic solvents.
The most important physical and chemical properties of acetaldehyde
are presented in the Summary of Chemical Safety Information (page
21).
1.3 Composition
Commercial acetaldehyde should contain at least 99% of the compound
and the acidity (as acetic acid) should be maximal 0.1%.
1.4 Analysis
The most specific and sensitive method, widely used, is based on the
derivatization of acetaldehyde (in most cases by
2,4-dinitro-phenylhydrazine) and subsequent analysis of the
hydrazone derivatives by high pressure liquid chromatography (HPLC)
or gas chromatography (GC). Analytical methods are available for the
detection of acetaldehyde in air, water, beverages, and blood.
1.5 Production and Uses
In Japan, production was estimated to be 328 000 tonnes in 1981. In
1982, the total acetaldehyde production in the USA amounted to 281
000 tonnes while in Western Europe, production was 706 000 tonnes in
1983.
Around 80% of the total production of acetaldehyde is made by
liquid-phase oxidation of ethylene using a catalytic solution of
palladium and copper chlorides. The remainder is produced by the
oxidation of ethanol and the hydration of acetylene.
The greater part of the acetaldehyde produced is used in the
production of acetic acid. It is also used in flavourings, foods,
beverages, perfumes, plastics, aniline dyes, synthetic rubber
manufacturing, the silvering of mirrors, gelatin fibre hardening,
and in the laboratory.
2. SUMMARY
2.1 Identity, Physical and Chemical Properties, and Analytical
Methods
Acetaldehyde is a colourless volatile liquid with a pungent
suffocating odour. The reported odour threshold is 0.09 mg/m3.
Acetaldehyde is a highly flammable and reactive compound that is
miscible in water and most common solvents.
Analytical methods are available for the detection of acetaldehyde
in air (including breath) and water. The principal method is based
on the reaction of acetaldehyde with 2,4-dinitrophenylhydrazine and
the subsequent analysis of the hydrazone derivatives using
high-pressure liquid chromatography or gas chromatography.
2.2 Sources of Human and Environmental Exposure
Acetaldehyde is a metabolic intermediate in humans and higher plants
and a product of alcohol fermentation. It has been identified in
food, beverages, and cigarette smoke. It is also present in vehicle
exhaust and in wastes from various industries. Degradation of
hydrocarbons, sewage, and solid biological wastes produces
acetaldehyde, as well as open burning and incineration of gas, fuel
oil, and coal.
More than 80% of acetaldehyde used commercially is produced by the
liquid-phase oxidation of ethylene with a catalytic solution of
palladium and copper chlorides.
The annual emission of acetaldehyde from all sources in the USA is
estimated to be 12.2 million kg.
2.3 Environmental Transport, Distribution, and Transformation
Intercompartmental transport of acetaldehyde is expected to be
limited because of its high reactivity. However, some transfer of
acetaldehyde to air from water and soil is expected, because of its
high vapour pressure and low sorption coefficient.
It is suggested that the photo-induced atmospheric removal of
acetaldehyde occurs predominantly via radical formation. Photolysis
is expected to contribute another substantial fraction to the
removal process. Both processes cause a reported daily loss of about
80% of atmospheric acetaldehyde emissions. Reported half-lives of
acetaldehyde in water and air are 1.9 h and 10-60 h, respectively.
Acetaldehyde is readily biodegradable.
2.4 Environmental Levels and Human Exposure
Levels of acetaldehyde in ambient air generally average 5 µg/m3.
Concentrations in water are generally less than 0.1 µg/litre.
Analysis of a wide range of foodstuffs in the Netherlands showed
that concentrations were generally less than 1 mg/kg (1 ppm), but,
occasionally, they ranged up to several 100 mg/kg, particularly in
some fruit juices and vinegar.
The principal source of exposure to acetaldehyde for the majority of
the general population is through the metabolism of alcohol.
Cigarette smoke is also a significant source of exposure. With
respect to other media, the general population is exposed to
acetaldehyde mainly from food and beverages and, to a lesser extent,
from air. The amounts contributed to total intake from
drinking-water are negligible.
Available data are inadequate to determine the extent of exposure to
acetaldehyde in the workplace. Workers may be exposed in some
manufacturing industries and in alcohol fermentation where the
principal route of exposure is most likely inhalation and possibly,
dermal contact.
2.5 Kinetics and Metabolism
2.5.1 Absorption, distribution, and elimination
Available studies on toxicity indicate that acetaldehyde is absorbed
through the lungs and gastrointestinal tract, but no adequate
quantitative studies have been identified. Absorption through the
skin is probable.
Following inhalation by rats, acetaldehyde is distributed to the
blood, liver, kidney, spleen, heart, and other muscles. Low levels
were detected in embryos after maternal i.p. injection of
acetaldehyde (mouse) and following maternal exposure to ethanol
(mouse and rat). Potential production of acetaldehyde has also been
observed in rat fetuses and the human placenta in vitro.
Distribution of acetaldehyde to brain interstitial fluid, but not to
brain cells, has been demonstrated following intraperitoneal
injection of ethanol. A high affinity, low-Km ALDHa may be
important in maintaining low levels of acetaldehyde in the brain
during the metabolism of ethanol.
In humans and the baboon, acetaldehyde is taken up by red blood
cells following ethanol consumption and can, in vivo, reach
intracellular levels that are 10 times greater than plasma levels.
Following oral administration, virtually no unchanged acetaldehyde
is excreted in the urine.
2.5.2 Metabolism
The major pathway for the metabolism of acetaldehyde is by oxidation
to acetate under the influence of NAD-dependent ALDH.a Acetate
enters the citric acid cycle as acetyl-CoA. There are several
isoenzymes of ALDH with different kinetic and binding parameters
that influence acetaldehyde oxidation rates.
ALDH activity has been localized in the respiratory tract epithelium
(excluding olfactory epithelium) in the rat, in the renal cortex and
tubules in the dog, rat, guinea-pig, and baboon, and in the testes
in the mouse.
Acetaldehyde is metabolized by mouse and rat embryonic tissue in
vitro. Acetaldehyde crosses the rat placenta despite placental
metabolism.
Though there is some metabolism in human renal tubules, the liver is
the most important site of metabolism of acetaldehyde.
Several isoenzymic forms of ALDH have been identified in human liver
and other tissues. There is polymorphism for the mitochondrial ALDH.
Subjects who are homozygous or heterozygous for a point mutation in
the mitochondrial ALDH corresponding gene have a low activity of
this enzyme, metabolize acetaldehyde slowly, and are intolerant of
ethanol.
The metabolism of acetaldehyde can be inhibited by crotonaldehyde,
dimethylmaleate, phorone, disulfiram, and calcium carbamide.
2.5.3 Reaction with other components
Acetaldehyde forms stable and unstable adducts with proteins. This
can impair protein function as evidenced by inhibition of enzyme
activity, impaired histone-DNA binding, and inhibition of
polymerization of tubulin.
Unstable adducts of acetaldehyde of undetermined significance occur
in vitro with nucleic acids.
Acetaldehyde can react with various macromolecules in the body,
preferentially those containing lysine residues, which can lead to
marked alterations in the biological function of these molecules.
a NAD = nicotinamide adenine dinucleotide.
ALDH = aldehyde dehydrogenase.
2.6 Effects on Organisms in the Environment
2.6.1 Aquatic organisms
LC50s in fish ranged from 35 (guppy) to 140 mg/litre (species not
specified). An EC5 of 82 mg/litre and an EC50 of 42 mg/litre
were reported for an alga and Daphnia magna, respectively.
2.6.2 Terrestrial organisms
Relatively low concentrations of acetaldehyde in air appear to be
toxic for some microoganisms.
Aphids were killed when exposed to acetaldehyde at a concentration
of 0.36 µg/m3 for 3 or 4 h.
Median lethal values were 8.91 mg/litre per h and 7.69 mg/litre per
h for the slug species, Arion hortensis and Agriolimax
reticulatus, respectively.
Inhibition of the seed germination of onion, carrot, and tomato by
acetaldehyde (up to 1.52 mg/litre) was reversible, whereas
inhibition of seed germination in Palmer amaranth, similarly
exposed, was irreversible; acetaldehyde at 0.54 g/m3 damaged
lettuce.
2.7 Effects on Experimental Animals and in vitro Test Systems
2.7.1 Single exposure
On the basis of the LD50s in rats and mice and the LC50s in rats
and Syrian hamsters, the acute toxicity of acetaldehyde is low.
Acute dermal studies were not available.
2.7.2 Short- and long-term exposures
In repeated dose studies by both the oral and inhalation routes,
toxic effects at relatively low concentrations were limited
principally to the sites of initial contact. In a 28-day study in
which acetaldehyde was administered in the drinking-water to rats,
effects were limited to slight focal hyperkeratosis of the
forestomach at 675 mg/kg body weight (no-observed-effect level
(NOEL): 125 mg/kg body weight). Following administration of a single
dose level of 0.05% in the drinking-water for 6 months (estimated by
the Task Group to be approximately 40 mg/kg body weight),
acetaldehyde induced synthesis of rat liver collagen, an observation
that was supported by in vitro data.
Following inhalation, NOELs for respiratory effects were 275
mg/m3 in rats exposed for 4 weeks and 700 mg/m3 in hamsters
exposed for 13 weeks. At lowest-observed-effect levels, degenerative
changes of the olfactory epithelium in rats (437 mg/m3) and
trachea in hamsters (2400 mg/m3) were observed. Degenerative
changes of the respiratory epithelium and larynx were observed at
higher concentrations. No repeated dose dermal studies were
available.
2.7.3 Reproduction, embryotoxicity, and teratogenicity
In several studies, parenteral exposure of pregnant rats and mice to
acetaldehyde induced fetal malformations. In the majority of these
studies, maternal toxicity was not evaluated. No data on
reproductive toxicity were identified.
2.7.4 Mutagenicity and related end-points
Acetaldehyde is genotoxic in vitro, inducing gene mutations,
clastogenic effects, and SCEs in mammalian cells in the absence of
exogenous metabolic activation, though negative results were
reported in adequate tests on Salmonella. Following
intraperitoneal injection, acetaldehyde induced SCEs in the bone
marrow of Chinese hamsters and mice. However, acetaldehyde
administered intraperitoneally did not increase the frequency of
micronuclei in early mouse spermatids. There is indirect evidence
from in vitro and in vivo studies to suggest that acetaldehyde
can induce protein-DNA and DNA-DNA cross-links.
2.7.5 Carcinogenicity
Increased incidences of tumours have been observed in inhalation
studies on rats and hamsters exposed to acetaldehyde. In rats, there
were dose-related increases in nasal adenocarcinomas and squamous
cell carcinomas (significant at all doses), and, in hamsters,
non-significant increases in nasal and laryngeal carcinomas. All
concentrations of acetaldehyde administered in the studies induced
chronic tissue damage in the respiratory tract.
2.7.6 Special studies
Adequate studies on the potential neuro- and immunotoxicity of
acetaldehyde were not found.
2.8 Effects on Humans
In limited studies on human volunteers, acetaldehyde was mildly
irritating to the eyes and upper respiratory tract following acute
exposure for very short periods to concentrations exceeding
approximately 90 mg/m3 and 240 mg/m3, respectively.
Cutaneous erythema was also observed in patch testing with
acetaldehyde, in twelve subjects of "oriental ancestry".
One limited investigation has been reported in which the incidence
of cancer was examined in workers exposed to acetaldehyde and other
compounds.
On the basis of indirect evidence, acetaldehyde has been implicated
as the putatively toxic metabolite in the induction of
alcohol-associated liver damage, facial flushing, and developmental
effects.
3. EVALUATION AND CONCLUSIONS
The acute toxicity in animals of acetaldehyde administered by the
inhalation or oral route is low. Acetaldehyde is mildly irritating
to the eyes and the upper respiratory tract in humans following
short exposures in air to concentrations exceeding approximately 90
mg/m3 and 240 mg/m3, respectively. Cutaneous erythema has
been observed in patch testing of humans.
Following oral administration of 675 mg/kg body weight per day to
rats, a borderline increase in hyperkeratosis of the forestomach was
observed (NOEL: 125 mg/kg body weight). In rats exposed to
approximately 40 mg/kg body weight in the drinking-water for 6
months, there was an increase in collagen synthesis in the liver.
In inhalation studies, the NOELs for respiratory effects were 275
mg/m3 in rats exposed for 4 weeks and 700 mg/m3 in hamsters
exposed for 13 weeks.
At concentrations that induce tissue damage in the respiratory
tract, increased incidences of nasal adenocarcinomas and squamous
cell carcinomas in the rat, and laryngeal and nasal carcinomas in
the hamster have been observed. There is suggestive evidence that
acetaldehyde causes genetic damage to somatic cells in vivo.
Available data are inadequate for the assessment of potential
reproductive, developmental, neurological, or immunological effects.
On the basis of data on irritancy in humans, a tolerable
concentration of 2 mg/m3 has been derived. Division of an effect
level for irritancy in the respiratory tract of rodents by an
uncertainty factor (1000), gave a tolerable concentration of 0.3
mg/m3. On the basis of the estimation of lifetime cancer risk
using the method of linear extrapolation, the concentrations
associated with a 10-5 excess lifetime risk are 11-65 µg/m3.
The limited data preclude definitive conclusions concerning the
risks of acetaldehyde for environmental biota. However, considering
the short half-lives of acetaldehyde in air and water and the fact
that it is readily biodegradable, the toxicity of acetaldehyde for
organisms in the aquatic and terrestrial environments is expected to
be low, except, possibly, during industrial discharges and spills.
4. HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION,
EMERGENCY ACTION
4.1 Human Health Hazards, Prevention and Protection, First Aid
The human health hazards associated with exposure to acetaldehyde,
preventive and protective measures, and first aid measures are
listed in the Summary of Chemical Safety Information in section 6.
The substance can be absorbed into the body by inhalation of its
vapour and by ingestion.
Liquid acetaldehyde and fairly low levels of the vapour are
irritating to the eyes, skin, and upper respiratory tract. Repeated
exposure may result in dermatitis (rarely).
Acute exposure to high levels of acetaldehyde vapour may result in
pulmonary oedema, preceeded by excitement, followed by narcosis.
Chronic effects due to acetaldehyde exposure seem unlikely, since
inhalation of toxicologically significant levels of acetaldehyde are
precluded by its irritant properties at fairly low levels.
4.2 Advice to Physicians
Inhaled steroids will help to prevent lung damage and oedema.
In the presence of wheezy breathing, the physician may consider the
subcutaneous application of ß2-sympathomimetics, such as
terbutaline sulfate (0.5 mg), followed, if necessary, by application
of a suppository containing aminophylline (360 mg).
In cases of suspected poisoning by acetaldehyde inhalation,
attention should be paid to the lungs and upper respiratory tract
for irritant effects.
When a victim has breathing difficulties, 100% oxygen can be
administered; if necessary, artificial respiration may be applied.
4.3 Health Surveillance Advice
Workers frequently exposed to acetaldehyde should be examined
periodically. Consideration should be given to the skin, eyes, and
respiratory tract.
4.4 Explosion and Fire Hazards, Prevention
4.4.1 Explosion and fire hazards
Acetaldehyde is highly flammable when exposed to heat or flame
(flashpoint, closed cup -38 °C). Acetaldehyde in air can be
explosive, explosion limits in air are 4.5-60.5 vol%. The
autoignition temperature is 185-193 °C.
The vapour of acetaldehyde is heavier than air, and may spread along
the ground and be ignited from a distance. Acetaldehyde can react
violently with acid anhydrides, alcohols, ketones, phenols, NH3,
HCN, H2S, halogens, P, isocyanates, strong alkalis, and amines.
Reactions with cobalt chloride, mercury(II) chlorate, or mercury
(II) perchlorate form sensitive, explosive products. Acetaldehyde
polymerizes violently in the presence of traces of metals and acids.
Reaction with oxygen may lead to detonation. When heated to
decomposition, it emits acid smoke and fumes.
4.4.2 Prevention
Use ventilation, non-sparking tools, and closed and explosion-proof
equipment and illumination sources. Do not smoke and do not use
acetaldehyde near other sources of ignition. Avoid contact of
acetaldehyde with oxidants. In case of fire, keep containers with
acetaldehyde cool by spraying with water.
4.4.3 Fire extinguishing agents
Fires can be extinguished with chemical powder, alcohol-resistant
foams, carbon dioxide, or a lot of water.
4.5 Storage
Acetaldehyde should be stored in the dark in tightly closed
containers, under cool and fireproof conditions with the addition of
an inhibitor. It must be stored away from substances with which it
can react, such as halogens, oxidative substances, amines, organic
substances, caustic solutions, concentrated sulfuric acid.
4.6 Transport
In case of an accident, stop the engine. Remove all sources of
ignition. Keep public away from danger area, mark the roads and keep
upwind. Use non-sparking handtools and explosion-proof electrical
equipment. Notify police and fire brigade immediately. In case of
spillage or fire, follow advice given in sections 4.4 and 4.7,
respectively. In case of poisoning, follow advice in the Summary of
Chemical Safety Information (section 6).
4.7 Spillage
In case of spillage of acetaldehyde, remove all ignition sources and
evacuate and ventilate the danger area. Ensure personal protection
(protective clothing, safety goggles and/or breathing protection),
and shut off leaks, if without risk. Collect the leaking liquid in
sealable containers. Absorb the spilt acetaldehyde in sand or an
inert absorbent and remove to a safe place; DO NOT absorb in sawdust
or other combustible absorbents. Remove vapour with fine water spray
and flush contaminated area with plenty of water. Prevent the liquid
from entering sewers and ditches.
If acetaldehyde has entered a water course or sewer, or, if it has
contaminated soil or vegetation, warn police.
5. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION
Acetaldehyde appears to be toxic, even at low concentrations and
with short periods of exposure, to fungi. It can also inhibit the
seed germination of several plants.
Contamination of the environment can be minimized by proper methods
of storage, handling, transport, and production, and by reducing the
emission sources (such as open burning, incineration of gas, fuel
oil, and coal). In case of spillage, apply methods recommended in
section 4.7.
6. SUMMARY OF CHEMICAL SAFETY INFORMATION
This summary should be easily available to all health workers
concerned with, and users of, acetaldehyde. It should be displayed
at, or near, entrances to areas where there is potential exposure to
acetaldehyde, and on processing equipment and containers. The
summary should be translated into the appropriate language(s). All
persons potentially exposed to the chemical should also have the
instructions in the summary clearly explained.
Space is available for insertion of the National Occupational
Exposure Limit, the address and telephone number of the National
Poison Control Centre, and local trade names.
SUMMARY OF CHEMICAL SAFETY INFORMATION
ACETALDEHYDE
CH3CHO; CAS Registry No.75-07-0
PHYSICAL PROPERTIES OTHER CHARACTERISTICS
Melting point -123.5 °C Acetaldehyde is a colourless liquid
Boiling point at 101.3 kPa 20.2 °C with a pungent suffocating odour;
Water solubility completely miscible in water the odour threshold in air is reported to
Specific density (20/4) 0.778 be 0.09 mg/m3; vapour is heavier than
Relative vapour density 1.52 air and may spread along the ground and
Vapour pressure (20 °C) 101.3 kPa be ignited from a distance; the compound
Autoignition temperature 185-193 °C may polymerize violently under the
Flash point, closed cup -38 °C influence of bases, with fire or explosion
Relative molecular mass 44.1 hazards; acetaldehyde is a strong reducing
Octanol/water partition agent and reacts violently with oxidants,
coefficient (log Pow) 0.63 causing fire and explosion hazards
HAZARD/SYMPTOM PREVENTION AND PROTECTION FIRST AID
SKIN: corrosive; redness, pain Wear plastic or synthetic rubber gloves, Remove soaked clothing, wash the skin with
apron, and boots plenty of water; obtain medical attention
immediately
EYES: corrosive; redness, pain, Wear safety goggles or face shield in Wash the eyes with plenty of water; remove
blurred vision combination with breathing protection contact lenses if easily possible; obtain
medical attention immediately
PHYSICAL PROPERTIES OTHER CHARACTERISTICS
INHALATION: corrosive; sore throat, Apply ventilation, exhaust hood and/or Remove victim to fresh air and keep victim
coughing, pulmonary oedema, breathing protection quiet in half-upright position; obtain
unconsciousness and effects medical attention immediately; subcutaneous
resembling alcoholic intoxication application of ß-sympathomimetic
substances
INGESTION: corrosive; abdominal Do not eat, drink, chew or smoke Rinse mouth; do not induce vomiting;
pains, diarrhoea, vomiting, burning during work; do not keep food in areas obtain medical attention immediately
sensation, dizziness, headache, with potential exposure; keep out of
nausea, unconsciousness reach of children
ENVIRONMENT: toxic to Minimize contamination of water, soil
micro-organisms, inhibits seed and atmosphere by proper methods of
germination in plants storage, handling, transport, and
production, and by reduction of
emission sources
SPILLAGE STORAGE FIRE AND EXPLOSION
Ensure personal protection; shut Store in fireproof, dark and cool Acetaldehyde is highly flammable;
off leaks, if without risk; remove conditions with addition of an avoid open fire or sparks; no smoking
ignition sources; evacuate and inhibitor; store separately from and no naked lights; no contact with
ventilate area; collect leaking halogens, oxidative substances, heated surfaces; in case of fire keep
liquid in closed containers; amines, oragnic substances, caustic containers cool by spraying water;
absorb spilt acetaldehyde in solutions, concentrated sulfuric extinguish fire with chemical powder,
sand or inert absorbent; remove acid alcohol-resistant foams, carbon dioxide, a
vapour with fine water spray and large amount of water; acetaldehyde vapour
flush area with plenty of water; in air may be explosive; ventilate; use
do not let run off into a sewer non-sparking tools, closed and
explosion-proof equipment
WASTE DISPOSAL
Dissolve in a combustible solvent,
such as alcohol or benzene, then
spray the solution in the furnace
with afterburner
7. CURRENT REGULATIONS, GUIDELINES, AND STANDARDS
7.1 Exposure Limits
Some exposure limits are given in the table on pages 26-29.
7.2 Specific Restrictions
In the USA, no power-operated truck may be used in atmospheres
where a hazardous concentration of the substance is present.
Current regulation of the EC:
Warning signs: F Easily flammable
Risk numbers: 12 Extremely flammable
36/37 Irritating to eyes and respiratory
system
Safety numbers: 9 Keep container in a well-ventilated
place
16 Keep away from sources of ignition-no
smoking
29 Do not empty into drains
33 Take precautionary measures against
static discharges
7.3 Labelling, Packaging, and Transport
United Kingdom
In the United Kingdom, the labelling of road tankers containing
acetaldehyde must be: "flammable liquid". Emergency action code:
2YE.
For labelling and packaging methods, the United Kingdom refers to
the EC (OJEC L.106,18,1982).
Germany
For labelling and packaging methods, Germany refers also to the
EC (OJEC L.106,18,1982).
CURRENT REGULATIONS, GUIDELINES, AND STANDARDS
Exposure limit values
Medium Specification Country/ Exposure limit description a Value Effective
organization date
AIR Occupational Argentina Maximum permissible concentration 1979
Time-weighted average (TWA) 180 mg/m3
Short-term exposure limit (STEL) 270 mg/m3
Australia Threshold limit value (TLV) 1985 (r)
Time-weighted average (TWA) 180 mg/m3
Short-term exposure limit (STEL) 270 mg/m3
Belgium Threshold limit value (TLV) 1987 (r)
Time-weighted average (TWA) 180 mg/m3
Short-term exposure limit 270 mg/m3
Canada Threshold limit value (TLV) 1980
Time-weighted average (TWA) 180 mg/m3
Short-term exposure limit (STEL) 270 mg/m3
Czechoslovakia Maximum acceptable concentration 1985
Time-weighted average (TWA) 200 mg/m3
Celing limit value (CLV) 400 mg/m3
Finland Maximum permissible concentration 1985 (r)
Time-weighted average (TWA) 90 mg/m3
Short-term exposure limit (STEL) 135 mg/m3
Germany (former Threshold limit value (TLV) 1987 (r)
FRG) Time-weighted average (TWA) 90 mg/m3
Short-term exposure limit (STEL) 180 mg/m3
(5-min TWA)
Medium Specification Country/ Exposure limit description a Value Effective
organization date
Air Occupational Germany (former Maximum acceptable concentration 1988 (r)
GDR) Short-term exposure limit (STEL) 100 mg/m3
Hungary Maximum acceptable concentration 1985 (r)
Time-weighted average (TWA) 50 mg/m3
Short-term exposure limit (STEL) 250 mg/m3
(30 min)
Italy Treshold limit value (TLV) 100 mg/m3 1985 (r)
Netherlands Maximum limit (MXL) 1987 (r)
Time-weighted average (TWA) 180 mg/m3
Poland Maximum permissible concentration 1985 (r)
Time-weighted average (TWA) 5 mg/m3
Romania Maximum permissible concentration 1985 (r)
Time-weighted average (TWA) 100 mg/m3
Ceiling limit value (CLV) 200 mg/m3
Sweden Hygienic limit value 1988
Time-weighted average (TWA) 45 mg/m3
Short-term exposure limit (STEL) 90 mg/m3
Switzerland Maximum work-site concentration 1987 (r)
Time-weighted average (TWA) 90 mg/m3
United Kingdom Recommended limit (RECL) 1987 (r)
Time-weighted average (TWA) 180 mg/m3
Short-term exposure limit (STEL) 270 mg/m3
USA Permissible exposure limit (PEL) 1987 (r)
Time-weighted average (TWA) 360 mg/m3
Medium Specification Country/ Exposure limit description a Value Effective
organization date
Air Occupational USA (ACGIH) Threshold limit value (TLV) 1987 (r)
Time-weighted average (TWA) 180 mg/m3
Short-term exposure limit (STEL) 270 mg/m3
former USSR Maximum acceptable concentration 1982 (r)
Ceiling limit value (CLV) 5 mg/m3 1977
AIR Ambient, former USSR Maximum acceptable concentration 1984
background 1 ×/day 0.01 mg/m3
average/day 0.01 mg/m3
Emission Germany (former Maximum limit (MXL) 0.15 mg/m3 1986
FRG)
Japan Maximum limit (MXL) 0.09-0.9 mg/m3 1982 (r)
emmision standard because of
offensive odour
WATER Surface former USSR Maximum acceptable concentration 0.2 mg/litre 1983
SOIL former USSR Maximum acceptable concentration 10 mg/kg 1985
a TWA = time-weighted average over one working day (usually 8 hours).
The substance is classified as harmful to water (class 2). In order
to protect water, appropriate security measures should be taken
during storage, loading, and transport.
United States of America
In the USA, acetaldehyde, when carried in bulk, is classified as a
"cargo of particular hazard" for purposes of regulations governing
handling of dangerous cargoes in, or contiguous to, waterfront
facilities. A permit is required for handling such cargo.
Unless in compliance with a specified procedure, owners/operators of
vessels, or on- or offshore facilities must notify the US Government
of any discharge of this substance in, or on, navigable waters,
adjoining shorelines or the contiguous zone in an amount equal to,
or greater than, 45 kg in any 24-h period. Such a discharge is a
violation of the Federal Water Pollution Control Act. When certain
specified vessels carrying acetaldehyde in bulk are bound for
departure from the US ports, the captain of the port must be
notified at least 24 h in advance.
Canada
Acetaldehyde is hazardous to the environment. The maximum amount per
package that may be transported on a cargo aircraft: 30 litres.
7.4 Discharges, Waste Disposal
In the USA, a permit is required for the discharge of any pollutant
from any point source into US waters. The following must report
quantitative data for the substance in their applications: every
applicant who has reason to believe that the substance is contained
in any of his outfalls inspection, monitoring and reporting
requirements after the issue of the permit are specified. Even if
not required in the permit, discharge of the substance must be
reported if it exceeds the highest of the following levels: (a) 100
mg/litre, (b) 5 times the maximum concentration reported in the
application, (c) the level established by the director of the
Environmental Protection Agency.
In the USA, acetaldehyde, including any isomers, hydrates, and
solutions and mixtures containing the substance, is designated as a
hazardous substance for the purposes of discharge (including
spilling, leaking, etc.) under the water pollution control act.
Acetaldehyde, if it is a commercial chemical product, is identified
in the USA as a "toxic waste" subject to regulation and notification
requirements.
BIBLIOGRAPHY
CEFIC (1979) Transport Emergency Cards for Individual Products.
CEFIC TEC(R)-620. London & Tonbridge, Whitefriars Press Ltd.
The Association of the Dutch Chemical Industry (1989) [Chemical
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den Rijn, Samson HD Tjeenk Willink (in Dutch).
Henschler D (1992) [Hazardous occupational materials. Toxicological
basis of exposure limits.] Weinheim: VCH Verlagsgesellschaft mbH, pp
1-3 (in German).
IARC (1985) Allyl compounds, aldehydes, epoxides and peroxides.
Lyon, International Agency for Research on Cancer, pp 101-132 (IARC
Monographs on the evaluation of carcinogenic risk of chemicals to
humans, Vol. 36).
IPCS/CEC (1990) International chemical safety card No. 0009:
Acetaldehyde. Luxembourg, Commission of the European Communities.
IRPTC (1992) Legal file 1992. Geneva, International Register of
Potentially Toxic Chemicals/UNEP.
Sittig M (1979) Hazardous and Toxic Effects of Industrial Chemicals.
Park Ridge, Noyes Data Corporation, pp 1-3.
WHO (in preparation) Environmental Health Criteria 167:
Acetaldehyde. Geneva, World Health Organization.