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    IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
    Health and Safety Guide No. 29

    DIMETHYL SULFATE
    HEALTH AND SAFETY GUIDE






    UNITED NATIONS ENVIRONMENT PROGRAMME

    INTERNATIONAL LABOUR ORGANISATION

    WORLD HEALTH ORGANIZATION




    WORLD HEALTH ORGANIZATION, GENEVA 1989

    This is a companion volume to Environmental Health Criteria 48:
    Dimethyl Sulfate

    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

    ISBN 92 4 154350 7
    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 1989

    Publications of the World Health Organization enjoy copyright
    protection in accordance with the provisions of Protocol 2 of the
    Universal Copyright Convention.  All rights reserved.

    The designations employed and the presentation of the material in this
    publication do not imply the expression of any opinion whatsoever on
    the part of the Secretariat of the World Health Organization
    concerning the legal status of any country, territory, city or area or
    of its authorities, or concerning the delimitation of its frontiers or
    boundaries.

    The mention of specific companies or of certain manufacturers'
    products does not imply that they are endorsed or recommended by the
    World Health Organization in preference to others of a similar nature
    that are not mentioned.  Errors and omissions excepted, the names of
    proprietary products are distinguished by initial capital letters.

    CONTENTS

    INTRODUCTION

    1. PRODUCT IDENTITY AND USES

         1.1. Identity
         1.2. Physical and chemical properties
         1.3. Analytical methods
         1.4. Production and uses

    2. SUMMARY AND EVALUATION

         2.1. Human exposure to dimethyl sulfate
         2.2. Fate of dimethyl sulfate
         2.3. Uptake, metabolism, and excretion
         2.4. Effects on organisms in the environment
         2.5. Effects on animals and human beings

    3. CONCLUSIONS AND RECOMMENDATIONS

    4. HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION, EMERGENCY ACTION

         4.1. Main human health hazards, prevention and protection, first
               aid
               4.1.1. Advice to physicians
               4.1.2. Health surveillance advice
         4.2. Explosion and fire hazards
         4.3. Storage
         4.4. Transport
         4.5. Spillage and disposal

    5. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    6. INTERNATIONAL CHEMICAL SAFETY CARD

    7. CURRENT REGULATIONS, GUIDELINES, AND STANDARDS

         7.1. Exposure limit values
         7.2. Specific restrictions
         7.3. Labelling, packaging, and transport

    BIBLIOGRAPHY
    

    INTRODUCTION

    The Environmental Health Criteria (EHC) documents 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 an International Chemical Safety Card
    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 Manager
    International Programme on Chemical Safety
    Division of Environmental Health
    World Health Organization
    1211 Geneva 27
    Switzerland

    THE INFORMATION IN THIS GUIDE SHOULD BE CONSIDERED AS A STARTING POINT
    TO A COMPREHENSIVE HEALTH AND SAFETY PROGRAMME

    1.  PRODUCT IDENTITY AND USES

    1.1  Identity

    Chemical formula:             (CH3)2SO4

    Common synonyms:              sulfuric acid dimethyl ester;
                                  methyl sulfate; dimethyl monosulfate;

    CAS registry number:          77-78-1

    RTECS number:                 WS8225000

    United Nations number:        1595

    Conversion factors:           1 ppm = 5 mg/m3 and 1 mg/m3 = 0.2 ppm,
                                  approximately, depending on temperature
                                  and pressure

    1.2  Physical and Chemical Properties

    Dimethyl sulfate is a colourless oily liquid with a very faint onion
    odour at room temperature and normal atmospheric pressure.  Its odour
    is mild and it produces no sensory irritation, so few people can
    detect the presence of the vapour in air.  It is readily soluble in
    alcohol, sparingly soluble in very cold water, but it dissolves
    readily in water at 18C with hydrolysis to form methanol, the
    monoester, and sulfuric acid.  Hydrolysis is particularly rapid in
    alkaline solutions which are therefore used for decontamination.  It
    is used as a methylating agent in organic syntheses.  Technical
    dimethyl sulfate contains small amounts of acid impurities, e.g., the
    monoester.

    1.3  Analytical Methods

    Sensitive analytical techniques are available to determine low levels
    of dimethyl sulfate.  Gas or liquid chromatography, in the latter case
    of a derivative, can be used, followed by an appropriate method of
    detection, such as mass spectrometry or a flame ionization detector
    for gas chromatography, and ultraviolet or visible spectrometry for
    liquid chromatography.  The lowest reported detection limit using gas
    chromatography is 0.026 mg/m3 (0.005ppm) for a 1-litre sample, and
    for liquid chromatography a detection limit of 0.05 mg/m3 (0.01 ppm)
    has been obtained.

    1.4  Production and Uses

    Dimethyl sulfate has been produced for some 60 years.  It can be made
    in a continuous process by the reaction of dimethyl ether with sulfur
    trioxide or by reacting methanol with oleum and distilling under
    vacuum.  Manufacture is concentrated in relatively few companies in

    Europe and North America, but no information on the magnitude of total
    production is available.  It is extensively used as a methylating
    agent, particularly in the dye industry and in the manufacture of
    organic chemicals, such as fabric softeners, and of pharmaceuticals. 
    For all the processes in which it is used there are alternative
    methylating agents, and no estimate of the amounts of dimethyl sulfate
    produced can be made from the quantities of these products.

    2.  SUMMARY AND EVALUATION

    2.1  Human Exposure to Dimethyl Sulfate

    Exposure of the skin and eyes, or the respiratory tract, to dimethyl
    sulfate may occur and the main effect is severe local inflammation
    that develops without sensory irritation at the moment of contact. 
    Because of this and its severe systemic toxicity, exposure of workers
    is controlled to a low level in industrial environments and there is
    virtually no exposure of the general population.  Designated
    occupational exposure limits range from 0.05 to 5 mg/m3 and these
    usually relate to skin exposure.  Those at the lower end of the range
    reflect concern about the possible carcinogenicity of the chemical. 
    In general, the substance is handled in closed systems, and it is
    usual for operators to wear impervious suits and self-contained
    breathing apparatus for operations involving the transfer of dimethyl
    sulfate, where there is the possibility of greater exposure.

    2.2  Fate of Dimethyl Sulfate

    Dimethyl sulfate released into the atmosphere eventually hydrolyses.
    The resulting sulfuric acid is deposited in rain and the methanol is
    oxidized to carbon dioxide and water or is deposited in rain.  The
    quantities released are likely to be so small that the contribution of
    these end-products to atmospheric levels of carbon dioxide and to acid
    rain is insignificant.  Spillages on the ground will evaporate and
    will hydrolyse in a similar way.

    When vessels containing dimethyl sulfate are vented to the atmosphere,
    an alkaline scrubber is usually incorporated to prevent any emission. 
    Spillages treated with ammonia or soda ash hydrolyse rapidly  in situ.

    2.3  Uptake, Metabolism, and Excretion

    Dimethyl sulfate is absorbed readily through mucous membranes, the
    intestinal tract, and the skin.  It is rapidly metabolized in
    mammalian tissues and when injected intravenously into rats is
    undetectable in the plasma after 3 minutes.  It is possible that the
    hydrolysis of dimethyl sulfate and the subsequent methylation of
    component molecules of the cells and tissues, including DNA, are
    responsible for its local effects, systemic toxic effects, and
    possible carcinogenicity.  On the eye, dimethyl sulfate produces toxic
    effects similar to those of methanol and it is probable that its
    toxicity is in part a direct result of the dissolved methanol moiety
    of the molecule as well as being a result of alkylation reactions. 
    The ultimate metabolites in the human body are sulfate and carbon
    dioxide, and these are excreted by the kidneys and released by the
    lungs, respectively.

    2.4  Effects on Organisms in the Environment

    Dimethyl sulfate hydrolyses fairly rapidly in damp environments at
    temperatures above about 20C.  High concentrations are therefore
    unlikely to persist following accidental contamination.  The 96-h
    LC50 values for aquatic species are generally in the range
    100-10 mg/litre.  The LC50 values for bluegill sunfish
    (Centrarchidae) and tidewater silversides (Atherinidae) are
    7.5 mg/litre and 15 mg/litre, respectively.


    2.5  Effects on Animals and Human Beings

    Dimethyl sulfate is toxic for all cells.  It causes severe
    inflammation of the eye, respiratory epithelium, and skin that
    commences minutes or hours after the exposure; there is little initial
    discomfort but severe functional disturbances follow.  In addition, it
    is readily absorbed and produces systemic toxic effects, principally
    on the nervous system, heart, liver, and kidneys.  Dimethyl sulfate is
    mutagenic and is a suspected human carcinogen.

    In short-term studies on experimental mammals, oral LD50 values of
    205 and 440 mg dimethyl sulfate/kg body weight (rat) and 140 mg/kg
    body weight (mouse) have been found; and a subcutaneous LD50 of
    100 mg/kg body weight has been demonstrated in the rat.  Rats inhaling
    a concentration of 75 mg dimethyl sulfate/m3 (15 ppm)  for 4 hours
    survived, but rats inhaling 150 mg/m3 (30 ppm)  for the same period
    died.  Other work with rats showed that with exposure for 4 hours the
    lowest observed lethal concentration was 150 mg/m3 (30 ppm), and
    that mean survival times for mice and guinea-pigs exposed to
    375 mg/m3 (75 ppm)  were 17 and 24 minutes, respectively.  Because
    of the delayed effects, concentrations producing eventual death after
    short exposures are likely to be a better guide to the toxicity of
    dimethyl sulfate than the time to death with continuous exposure at a
    particular concentration.

    Dimethyl sulfate is mutagenic in several  in vitro test systems.  It
    has produced tumours of the nasal epithelium and the nervous system
    when fed to pregnant rats, and single injections resulted in malignant
    tumours of the nervous system in their offspring.  Inhalational
    exposure of rats for 1 hour per day, 5 days per week, for 130 days, to
    calculated concentrations of 55 mg/m3 (10 ppm) and 17 mg/m3
    (3 ppm) resulted at 643 days in 5 of the 15 survivors at the higher
    dosage and 3 of the 20 at the lower dosage having tumours.  Most
    tumours were of the nasal epithelium or the central nervous system.

    The effects on man have been well described and the acute effects of
    vapour exposure are uniform.  The initial symptoms are headache,
    giddiness, and burning of the eyes, which reach a maximum intensity
    between 2 and 10 hours after exposure.  Epithelial irritation follows,
    not merely of the exposed respiratory epithelium but also of the

    intestinal and urinary tracts.  Thus, there is soreness of the nose
    and throat with hoarseness of the voice, cough, tightness of the
    chest, breathing difficulty, difficulty in swallowing, and also
    vomiting and diarrhoea and painful urination.  These symptoms may
    persist for up to 2 weeks.  The role of secondary infection of the
    damaged epithelia is not clear.  In severe cases, there may be
    exudative pulmonary oedema, which can be fatal.  The cardiotoxicity
    may lead to circulatory collapse.  Biochemical tests have remained
    abnormal for periods of years following acute exposure and permanent
    changes in colour vision and visual field changes have been described.

    The clinical effects of chronic exposure have been reported to involve
    liver function and vision in particular.  These, like the exposure,
    are likely to go unnoticed unless monitored.

    Human carcinogenicity was suggested by a study of a small group of
    workers in an environment where acute toxic effects were not uncommon. 
    This study showed that 4 out of 10 workers had died of bronchogenic
    carcinoma.  However, epidemiological studies among the work-forces of
    two major producers have failed to show an elevated cancer incidence
    and occupational exposure at 5 mg/m3 appears to be below the
    threshold for a demonstrable carcinogenic risk for man. 

    3.  CONCLUSIONS AND RECOMMENDATIONS

    Dimethyl sulfate is a particularly dangerous chemical because of its
    systemic and local toxicity and because there is no warning of
    exposure.  While the carcinogenic risk appears not to be significant
    under good industrial conditions, the reported high incidence of lung
    cancer in a small, highly exposed work-force, and the animal data,
    indicate that there may be a carcinogenic hazard for man.  Exposure to
    high concentrations even for short periods should therefore be
    avoided.  In addition to the acute effects of acute exposure, there is
    a risk of permanent or long-term damage to the liver and retina. 
    These organs also appear to be the most sensitive to the effects of
    chronic exposure.

    The toxicity of dimethyl sulfate is such that it should be handled
    only within organizations having the resources and ability to carry
    out the engineering controls, workplace monitoring, sophisticated
    personal protection, occupational health surveillance, and emission
    treatment and control necessary to protect the work-force, the
    community, and the environment.

    4.  HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION, EMERGENCY ACTION

    4.1  Main Human Health Hazards, Prevention and Protection, First Aid

    The main hazard for man is unperceived exposure, which could lead to
    severe or lethal acute effects, and also to long-term health effects
    including possible carcinogenesis.  High levels of engineering and
    process control are required to ensure that the possibility of
    emissions is remote.  Flange joints between plant components should be
    avoided and welded joints should be used instead.  Factory areas
    containing dimethyl sulfate should be enclosed by bunds and staff
    should have the necessary materials and equipment to treat spillages
    immediately with alkaline solutions or soda ash so that the dimethyl
    sulfate is rapidly hydrolysed.  Vents should discharge through an
    alkaline scrubber.  Continuous atmospheric monitoring for dimethyl
    sulfate levels is desirable so that immediate warning is given of
    significant workplace concentrations.  The filling of storage tanks or
    reactors from drums, tankers, or tank cars should be undertaken only
    by experienced operators who are fully protected by impervious suits
    and by positive-pressure, demand, breathing apparatus supplied with
    respirable air from a cylinder or a remote source.  Fully protected
    employees may deal with any small spillages that occur during
    transfers but they should be strictly instructed not to attempt to
    deal with larger spillages.  Nearly all accidents with dimethyl
    sulfate have been the result of hasty and uninformed cleaning-up
    operations.  Such spillages should be dealt with by specially trained
    and fully protected personnel.

    4.1.1  Advice to physicians

    In the event of suspected inhalation of vapour, even in the absence of
    any symptoms, patients should be kept resting quietly under clinical
    observation for at least 12 hours.  The eyes should be irrigated, even
    if apparently unaffected, with a 2% solution of sodium bicarbonate for
    a full 15 minutes.  Eye irrigation should be repeated if any redness
    develops.  Oxygen may be administered if there is breathing
    difficulty.  Arrangements should be made for the possibly affected
    patient to be transferred to the nearest centre equipped for the
    treatment of pulmonary oedema, the support of patients with major
    organ failure, and circulatory collapse.

    No specific antidote is known.  In the case of contamination of the
    body surface, irrigate affected eyes and skin burns with a 2% solution
    of sodium bicarbonate in water and treat conventionally. 
    Hydrocortisone or other steroid drops may be useful.

    With inhalation exposure, the administration of high doses of methyl
    prednisolone (30 mg/kg body weight, by slow intravenous injection) or
    the administration of other steroids (e.g., beclometasone
    dipropionate) by metered-dose aerosol has been reported to reduce the

    incidence of exudative pulmonary oedema and subsequent pulmonary
    fibrosis.  The prophylactic use of steroids after exposure, but before
    any signs and symptoms appear, may be of value in reducing pulmonary
    damage by dimethyl sulfate.  An early chest X-ray may be useful for
    comparison with a later film in the event of the development of
    pulmonary oedema.  Oral or aerosol bronchodilators (e.g., salbutamol)
    may be of value if there is bronchospasm.  Oxygen and humidification
    are the main lines of treatment for mild pulmonary oedema; diuretics,
    opiates, and theophyllines do not have a role, since the condition is
    exudative rather than transudative.  In extreme cases, intermittent
    positive-pressure ventilation may be necessary.  Prophylactic
    antibiotics are generally indicated, since secondary bacterial
    infection of the airways often occurs.

    If there is oesophageal, ophthalmic, or urinary tract pain, analgesics
    may be given, but those that are respiratory depressants or topical
    irritants should be avoided.  Oral medication should be avoided if
    there is nausea or upper abdominal pain.

    Heart rate, blood pressure, fluid balance, arterial blood gases, and
    liver and renal function should be monitored, and support should be
    given on general lines if there are signs of circulatory, liver, or
    renal failure.

    A detailed neurological and ophthalmological assessment should be made
    as early as possible and during the recovery phase.

    Where no symptoms or signs have appeared within 12 hours, the patient
    may be discharged from observation, but should be warned to return if
    any symptoms develop.

    As dimethyl sulfate can be metabolized to methanol, there is the
    theoretical possibility of superadded methanol poisoning, although
    this has never been reported in human poisoning cases.  If methanol
    poisoning is suspected, the serum methanol level can be determined and
    metabolic acidosis corrected with sodium bicarbonate.  Specific
    treatment for methanol poisoning should be given if indicated.

    A particularly difficult situation may arise when symptoms that could
    be a result of dimethyl sulfate exposure, but could equally well be an
    incipient upper respiratory tract infection or conjunctivitis, occur
    in workers in the plant without a history of exposure.  Such people
    may seek advice because they know that exposure may be imperceptible. 
    In such situations, the correct course of action will depend on a
    careful history of the presenting complaints, of the occurrence of
    similar symptoms in other members of the household or work-group, of
    the timing of the onset of symptoms in relation to the last
    work-period, and of any abnormal conditions or events in the plant
    that could have led to exposure.  Medical and nursing staff who know
    their employees may also be able to take personality factors into
    account.

    4.1.2  Health surveillance advice

    It may be advisable for persons with pre-existing respiratory or liver
    disease to be excluded from work with dimethyl sulfate.  Preplacement
    examinations should also document the visual fields and the colour
    vision status of the employee or recruit.

    Wherever measured exposures are close to the occupational exposure
    limit or there is dependence on personal protection to limit exposure,
    it is wise to undertake regular health surveillance, including tests
    of liver and pulmonary function, colour vision, and visual fields.

    4.2  Explosion and Fire Hazards

    Dimethyl sulfate represents a moderate fire hazard, but does not
    explode.  Firefighters should wear full protective clothing and use
    compressed-air breathing apparatus.  Water, foam, dry powder, or
    carbon dioxide are suitable firefighting media.

    4.3  Storage

    Dimethyl sulfate should be stored in the suppliers' drums, properly
    sealed and labelled, or in a suitable bulk container.  These should be
    housed in a cool, dry, well-ventilated place.  Handle drums carefully
    to avoid puncturing.

    4.4  Transport

    In case of a road transport accident, stop the motor and remain
    up-wind.  If a vapour cloud drifts towards an inhabited area, warn the
    inhabitants and evacuate areas close to the spillage, if this can be
    done without risking exposure.

    4.5  Spillage and Disposal

    Spillage should only be dealt with by trained personnel wearing full
    protective clothing, a full-face mask, and positive-pressure breathing
    apparatus.  Soda ash or 3% ammonia solution may be applied to liquid
    spills.  Sprays of 3% ammonia solution may be used to "knock down" the
    vapour over spillages.  After complete neutralization, spillages may
    be washed away to a drain or sewer.  If dimethyl sulfate has entered a
    watercourse or sewer, or contaminated soil or vegetation, advise the
    police and public authorities.

    For the treatment and disposal of waste, the recommended methods are
    alkaline hydrolysis, incineration, and landfill.  Do not use open
    burning (e.g., as a boiler fuel) or evaporation for waste disposal.

    For incineration, dimethyl sulfate should be dissolved in a
    combustible solvent and sprayed into a furnace with an afterburner and
    an alkali scrubber.

    Dimethyl sulfate may be decomposed by adding a dilute alkaline
    solution; the mixture should be stirred and then allowed to settle. 
    The resulting solution is then neutralized by acid or alkali as
    appropriate and drained into a sewer.  When rapid decomposition is
    needed the waste may be warmed.

    It may also be adsorbed on vermiculite, packed in drums, buried and
    covered immediately.

    5.  HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    There are no hazards for the environment from the controlled transport
    and use of dimethyl sulfate.  Spillages will cause local damage, but
    rapid hydrolysis of the material will prevent persistent or widespread
    effects, particularly in temperate conditions.

    6.  INTERNATIONAL CHEMICAL SAFETY CARD

     This card should be easily available to all health workers concerned
     with, and users of, dimethyl sulfate. It should be displayed at, or
     near, entrances to areas where there is potential exposure to
     dimethyl sulfate, and on processing equipment and containers. The
     card should be translated into the appropriate language(s). All
     persons potentially exposed to the chemical should also have the
     instructions on the chemical safety card clearly explained.

     Space is available on the card for insertion of the National
     Occupational Exposure Limit, the address and telephone number of the
     National Poison Control Centre, and for local trade names.


        DIMETHYL SULFATE
    Chemical formula: (CH3)2SO4)       CAS Registry No. 77-78-1
    RTECS No. WS8225000
                                                                                                                                              
    PHYSICAL PROPERTIES                                                                  OTHER CHARACTERISTICS
                                                                                                                                              

    Melting point                           -32C                                        Dimethyl sulfate is a colourless, oily liquid with
    Boiling point                           188C (decomposes)                           a faint onion-like odour; it is readily soluble in
    Water solubility (18C)                 28 g/litre (readily soluble)                 alcohol and aromatic solvents, but is only sparingly
    Relative density (20-24C)              1.332                                        soluble in cold water; it hydrolyses in water to the
    Relative vapour density                 4.4                                          monoester, sulfuric acid, and methanol; hydrolysis is
    Vapour pressure (20C)                  67 Pa (0.5 mmHg)                             more rapid in alkaline solutions; it is combustible
    Flash point                             83C                                         but not explosive
    Relative molecular mass                 126.13
                                                                                                                                              
    HAZARDS/SYMPTOMS                        PREVENTION AND PROTECTION                    FIRST AID
                                                                                                                                              

     Vapour

    EYES: severe delayed inflammation       Meticulously engineered, totally             Prompt irrigation with 2% sodium
    without initial irritation; high        enclosed plant is required, with             bicarbonate solution for at least
    acute exposures and chronic             alkaline scrubbers for vents to              15 minutes, even if there is no irritation;
    exposures may cause visual field        atmosphere; ideally there should             obtain medical advice
    defects and colour vision changes,      be continuous monitoring for
    but this may be a systemic effect       concentrations in the workplace
                                            atmosphere; complete impervious suits
                                            and full-face positive pressure demand
                                            compressed-air breathing apparatus
                                            should be available for operations in
                                            which dimethyl sulfate is not contained,
                                            and for clean-up of spillages
                                                                                                                                              

    DIMETHYL SULFATE (cont'd)
                                                                                                                                              
    HAZARDS/SYMPTOMS                        PREVENTION AND PROTECTION                    FIRST AID
                                                                                                                                              

    INHALATION: no warning smell            See above                                    Keep under observation for at least
    or irritation; severe delayed                                                        12 hours after possible exposure, even if 
    irritation of the whole of the                                                       there are no symptoms; keep at rest; 
    respiratory epithelium may result;                                                   administer oxygen if there is breathing 
    the consequence is exudative                                                         difficulty; refer to hospital or a doctor
    pulmonary oedema, which may
    be fatal


    Liquid

    SKIN: delayed skin burns and            Measures effective against                   Wash skin thoroughly with a 2% solution
    systemic absorption leading to          respiratory exposure will be                 of sodium bicarbonate in water; remove
    serious, possibly fatal, effects        effective against skin exposure              any contaminated clothing (using gloves);
    on the nervous system, liver,                                                        send to a hospital or doctor; treat burns
    kidneys, and heart; there may be                                                     conventionally; observe for systemic
    convulsions, visual disturbance,                                                     effects
    pain on voiding the bladder, pain
    on swallowing, and vomiting

    INGESTION: Severe, possibly             Do not eat, drink, or smoke                  Do not induce vomiting; give nothing
    delayed, effects on the mouth,          where chemicals are handled                  by mouth; send patient immediately to
    throat, and oesophagus would                                                         hospital or to a doctor for treatment
    be expected with severe systemic
    effects
                                                                                                                                              
        7.  CURRENT REGULATIONS, GUIDELINES, AND STANDARDS

    The information given in this section has been extracted from the
    International Register of Potentially Toxic Chemicals (IRPTC) legal
    file.

    The reader should be aware that regulatory decisions about chemicals
    taken in a certain country can only be fully understood in the
    framework of the legislation of that country.a When no effective
    date appears in the IRPTC legal file, the year of the reference from
    which the data are taken is indicated by (r).

    7.1  Exposure Limit Values

    Some exposure limit values are given in the following table.

    7.2  Specific Restrictions

    In the USA, dimethyl sulfate is designated as a hazardous waste. Any
    solid waste (except domestic waste) containing dimethyl sulfate is
    subject to regulations as regards handling, transport, treatment,
    storage, and disposal. Commercial dimethyl sulfate products are
    designated toxic waste and subject to similar regulations.

    7.3  Labelling, Packaging, and Transport

    In the countries of the European Economic Community, dimethyl sulfate
    is classified as very toxic and a possible carcinogen. The label on a
    container must read:

          Very toxic; may cause cancer; also toxic if swallowed; also very
          toxic by inhalation; causes burns; avoid exposure - obtain
          special instructions before use. In case of contact with eyes,
          rinse immediately with plenty of water and seek medical advice.
          Take off immediately all contaminated clothing. In case of
          accident or if you feel unwell seek medical advice immediately
          (show the label where possible).

    In Czechoslovakia, dimethyl sulfate is subject to labelling
    requirements. In Sweden, it is labelled as a carcinogen and a very
    hazardous product with the symbol "T". In Japan, it is a designated
    deleterious substance for labelling purposes. In the United Kingdom,
    road tankers transporting dimethyl sulfate must be labelled "Toxic
    Substance".

                 

    a  The regulations and guidelines of all countries are subject to
       change and should always be verified with the appropriate
       regulatory authorities before application.

    For transport, the United Nations classifies dimethyl sulfate as a
    "poisonous substance", and for packing as a "very dangerous
    substance". For marine transport, the International Maritime
    Organization uses the same classifications.


        EXPOSURE LIMIT VALUES
                                                                                                                                  
    Medium    Specification    Country/          Exposure limit description                        Value                Effective
                               organization                                                                               date
                                                                                                                                  

    AIR       Occupational     Australia         Threshold limit value (TLV)                                              1985 (r)
                                                 - Time-weighted average (TWA)                     5 mg/m3
                                                                                                   (carcinogen)
                                                                                                   (skin absorption)

                               Belgium           Threshold limit value                                                    1987 (r)
                                                 - Time-weighted average                           0.5 mg/m3
                                                                                                   (carcinogen)
                                                                                                   (skin absorption)

                               Brazil            Acceptable limit                                  0.4 mg/m3              1982 (r)
                                                 - 48 h/week                                       (hazardous degree:
                                                                                                   maximum)

                               Canada            Threshold limit value                                                    1980
                                                 - Time-weighted average                           0.5 mg/m3
                                                                                                   (carcinogen)

                               Czechoslovakia    Maximum allowable concentration (MAC)                                    1985
                                                 - Time-weighted average                           0.05 mg/m3
                                                 - Ceiling value (CLV)                             0.1 mg/m3

                               Finland           Maximum permissible concentration (MPC)                                  1985 (r)
                                                 - Time-weighted average                           5 mg/m3
                                                                                                   (carcinogen)
                                                                                                   (skin absorption)

                               German            Maximum allowable concentration                                          1985 (r)
                                 Democratic      - Time-weighted average                           5 mg/m3
                                 Republic        - Short-term exposure limit (STEL)                5 mg/m3
                                                                                                   (skin absorption)
                                                                                                                                  

    EXPOSURE LIMIT VALUES (cont'd)
                                                                                                                                  
    Medium    Specification    Country/          Exposure limit description                        Value                Effective
                               organization                                                                               date
                                                                                                                                  

    AIR       Occupational     Germany,          Technical reference concentration                                        1987 (r)
                                 Federal         - Time-weighted average; 1 year                   0.1 mg/m3
                                 Republic of     - Carcinogenic working material proven            (production)
                                                   in animal experiments. No maximum               0.2 mg/m3 (use)
                                                   work-site concentration established
                                                   (cutaneous absorption)

                               Hungary           Maximum allowable concentration                                          1985 (r)
                                                 - Time-weighted average                           5 mg/m3
                                                 - Short-term exposure limit                       5 mg/m3
                                                   (30 minutes)                                    (skin absorption)
                                                                                                   (sensitizer)

                               Italy             Threshold limit value (TLV)                                              1985(r)
                                                 - Time-weighted average                           0.05 mg/m3
                                                                                                   (carcinogen)
                                                                                                   (skin absorption)

                               Japan             Maximum allowable concentration                                          1986
                                                 - Time-weighted average                           0.5 mg/m3
                                                                                                   (carcinogen)
                                                                                                   (skin absorption)

                               Netherlands       Maximum limit                                                            1987 (r)
                                                 - Ceiling value                                   0.5 mg/m3
                                                                                                   (skin absorption)

                               Poland            Maximum permissible concentration                                        1985 (r)
                                                 - Ceiling value                                   1 mg/m3
                                                                                                                                  

    EXPOSURE LIMIT VALUES (cont'd)
                                                                                                                                  
    Medium    Specification    Country/          Exposure limit description                        Value                Effective
                               organization                                                                               date
                                                                                                                                  

    AIR       Occupational     Romania           Maximum permissible concentration                                        1985 (r)
                                                 - Time-weighted average                           3 mg/m3
                                                 - Ceiling value                                   8 mg/m3
                                                                                                   (skin absorption)

                               Sweden            No exposure limit established                     Carcinogenic           1985
                                                                                                   substance

                               Switzerland       Maximum work-site concentration                                          1987 (r)
                                                 - Time-weighted average                           0.1 mg/m3
                                                                                                   (carcinogen)
                                                                                                   (skin absorption)

                               United            Recommended limit                                                        1987 (r)
                                 Kingdom         - Time-weighted average                           0.5 mg/m3
                                                 - Short-term exposure limit                       0.5 mg/m3
                                                   (10-minutes time-weighted average)              (skin absorption)

                               USA               Threshold limit value                                                    1987
                                 (ACGIH)         - Time-weighted average                           0.5 mg/m3
                                                                                                   (suspected
                                                                                                   carcinogen)
                                                                                                   (skin absorption)

                               USA (OSHA)        Permissible exposure limit (PEL)                                         1974
                                                 - Time-weighted average                           5 mg/m3
                                                                                                   (skin absorption)

                               USSR              Maximum allowable concentration                                          1983
                                                 - Ceiling value                                   0.1 mg/m3
                                                                                                                                  

    EXPOSURE LIMIT VALUES (cont'd)
                                                                                                                                  
    Medium    Specification    Country/          Exposure limit description                        Value                Effective
                               organization                                                                               date
                                                                                                                                  

    AIR       Occupational     Yugoslavia        Maximum allowable concentration                                          1985 (r)
                                                 - Time-weighted average                           5 mg/m3
                                                                                                   (skin absorption)
                                                                                                                                  
        BIBLIOGRAPHY

    ACGIH (1986)  Documentation of the threshold limit values and
     biological exposure indices. Cincinnati, American Conference of
    Governmental Industrial Hygienists.

    CLAYTON, G.D. & CLAYTON, F.E. (1981)  Patty's industrial hygiene and
     toxicology. Vol. 2A. New York, Wiley - Interscience, John Wiley &
    Sons.

    DUTCH ASSOCIATION OF SAFETY EXPERTS (1980)  Handling chemicals safely.
    2nd ed. Dutch Chemical Industry Association, Dutch Safety Institute.

    GOSSELIN, R.E., et al. (1976)  Clinical toxicology of commercial
     products. 4th ed. Baltimore, Maryland, Williams and Wilkins Company.

    IRPTC (1988)  Data profile (legal file, waste disposal file, treatment
     of poisoning file), Geneva, International Register of Potentially
    Toxic Chemicals.

    SAX, N.I. (1984)  Dangerous properties of industrial materials. New
    York, Van Nostrand Reinhold Company.

    US NIOSH (1976)  A guide to industrial respiratory protection.
    Cincinnati, Ohio, US National Institute for Occupational Safety and
    Health.

    US NIOSH/OSHA (1985)  Pocket guide to chemical hazards. Washington
    DC, US National Institute for Occupational Safety and Health,
    Occupational Safety and Health Association (Publication No. 85.114).

    US NIOSH/OSHA (1981)  Occupational health guidelines for chemical
     hazards. 3 vol. Washington DC, US National Institute for
    Occupational Safety and Health, Occupational Safety and Health
    Association, (Publication No. 01.123).

    WHO (1988)  Dimethyl sulfate. Geneva, World Health Organization.
    (Environmental Health Criteria 48).
    


    See Also:
       Toxicological Abbreviations
       Dimethyl sulfate (EHC 48, 1985)
       Dimethyl sulfate (ICSC)
       Dimethyl Sulfate (IARC Summary & Evaluation, Volume 71, 1999)