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    IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
    Health and Safety Guide No. 35

    PHOSPHORUS TRICHLORIDE AND PHOSPHORUS OXYCHLORIDE
    HEALTH AND SAFETY GUIDE






    UNITED NATIONS ENVIRONMENT PROGRAMME

    INTERNATIONAL LABOUR ORGANISATION

    WORLD HEALTH ORGANIZATION




    WORLD HEALTH ORGANIZATION, GENEVA 1989

    Please note that there is no Environmental Health Criteria document
    for this Health and Safety Guide.

    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)

    ISBN 92 4 154356 6
    ISSN 0259-7268

    (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.  For rights of reproduction  or
    translation of WHO publications, in part or  in toto, application
    should be made to the Office of Publications, World Health
    Organization, Geneva, Switzerland.  The World Health Organization
    welcomes such applications.

    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.

    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.

    CONTENTS

    INTRODUCTION

    1. PRODUCT IDENTITY AND USES
         1.1. Identity
         1.2. Physical and chemical properties
              1.2.1. Phosphorus trichloride
              1.2.2. Phosphorus oxychloride
         1.3. Analytical methods
         1.4. Production and uses

    2. SUMMARY AND EVALUATION
         2.1. Exposure to phosphorus trichloride and phosphorus
              oxychloride
         2.2. Fate of phosphorus trichloride and phosphorus oxychloride
         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
         3.1. Conclusions
         3.2. Recommendations

    4. HUMAN HEALTH HAZARDS, PREVENTION AND PROTECTION, EMERGENCY ACTION
         4.1. Human health hazards, prevention and protection, first aid
              4.1.1. Prevention and protection
              4.1.2. First aid
         4.2. Advice to physicians
         4.3. Health surveillance advice
         4.4. Explosions and fire hazards
         4.5. Storage
         4.6. Transport
         4.7. Spillage and disposal
              4.7.1. Spillage
              4.7.2. 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 human health from exposure to a
    chemical or combinations of chemicals, or to 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 those in the occupational health
    services, ministries, governmental agencies, industry, and trade
    unions, who are involved in the safe use of chemicals and the
    prevention of environmental health hazards, and those workers wanting
    more information on this topic.  An attempt has been made to use only
    terms that are familiar to the user.  However, sections 1 and 2
    inevitably contain some technical terms.  A bibliography has been
    included for readers who would like to have 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

                            Phosphorus             Phosphorus
                            Trichloride            Oxychloride

    Chemical formula:       PCl3                   POCl3

    Chemical structure:           Cl                      Cl
                                   '                       '
                              Cl - P                  Cl - P = O
                                   '                       '
                                  Cl                      Cl

    Common synonyms:        Phosphorus chloride;   Phosphorus
                            phosphorous chloride;  oxytrichloride
                            trichlorophosphine

    Abbreviation:           Tri; "Pickle"          Oxy; "Pockle"

    CAS registry number:    7719-12-2              10025-87-3

    RTECS number:           TH3675000              TH4897000

    UN number:              1809                   1810 (II)

    Conversion factor:      1 ppm = 5.62 mg/m3     1 ppm = 6.27 mg/m3
                            and                    and
                            1 mg/m3= 0.178 ppm     1 mg/m3= 0.159 ppm
                            [at 25 °C              [at 25 °C
                            and 101.3 kPa          and 101.3 kPa
                            (760 mmHg, 1 bar)]     (760 mmHg, 1 bar)]

    1.2  Physical and Chemical Properties

    1.2.1  Phosphorus trichloride

    Phosphorus trichloride is a colourless or light-yellow volatile liquid
    at room temperature and normal atmospheric pressure.  It has a pungent
    odour that can be detected at about 0.5 mg/m3. The liquid reacts
    violently with water producing heat and decomposition products that
    include hydrochloric and phosphorous acids. It reacts exothermically
    with alcohols and phenols to produce phosphite esters and hydrogen
    chloride.  The vapour reacts with water vapour in the air producing
    visible fumes of hydrogen chloride (HCl) and phosphorous acid or
    phosphorus oxides and oxyacids (all of which are simple irritants). 
    Impurities that may be present in small amounts (<0.1%) include the
    arsenic and bromine analogues of phosphorus trichloride.  The presence
    of these impurities and the hydrolysis products does not change the
    overall toxicity of technical phosphorus trichloride.

    1.2.2  Phosphorus oxychloride

    Phosphorus oxychloride is a colourless volatile liquid at room
    temperature and normal atmospheric pressure.  It has a pungent odour
    that can be detected at about 0.5 mg/m3.  The liquid reacts
    violently with water producing heat and decomposition products that
    include hydrochloric and phosphoric acids.  It reacts exothermically
    with alcohols and phenols to produce phosphate esters and hydrogen
    chloride. The vapour reacts with water in the air to produce visible
    fumes of hydrogen chloride (HCl) and phosphoric acid or its anhydride
    (H3PO4 or P4O10, which are simple irritants). Impurities that
    may be present in small amounts (<0.1%) include: phosphorus
    trichloride, phosphorus pentachloride, phosphoric anhydride, and the
    arsenic and bromine analogues of phosphorus oxychloride.  The presence
    of these impurities and the hydrolysis products does not change the
    overall toxicity of technical phosphorus oxychloride.

    Some physical and chemical properties of phosphorus trichloride and
    phosphorus oxychloride are given in the International Chemical Safety
    Card (section 6).

    1.3  Analytical methods

    It is difficult to measure phosphorus trichloride and phosphorus
    oxychloride levels in the air because of their reactivity with
    atmospheric moisture.  Existing analytical methods do not distinguish
    between phosphorus trichloride or phosphorus oxychloride and their
    hydrolysis products (see section 1.2).

    In ambient air, phosphorus trichloride and phosphorus oxychloride are
    absorbed onto silica gel that will also absorb any hydrolysis
    products.  The gel is then desorbed and the resulting chloride,
    phosphite, and phosphate ions are identified and quantified by ion
    chromatography.

    Alternatively, air can be bubbled through a liquid impinger containing
    distilled water. Aliquots of the water are analysed for phosphate
    (e.g., sodium molybdate/heteropoly blue complex) with and without
    prior oxidation by bromine water. The difference represents phosphite,
    which, when multiplied by 2.8, gives the equivalent amount of
    phosphorus trichloride.

    1.4  Production and Uses

    Both phosphorus trichloride and phosphorus oxychloride are
    large-volume chemicals produced and used worldwide.

     Phosphorus trichloride is produced by reacting yellow phosphorus
    with chlorine.  It is used as an intermediate in the manufacture of
    phosphite esters, organophosphorus pesticides, and organophosphines. 
    It is also used as a chlorinating agent and a chemical intermediate in
    the manufacture of phosphorus oxychloride, surfactants, and
    stabilizers, and in the production of special metallic deposits.

     Phosphorus oxychloride is produced by oxidizing phosphorus
    trichloride or by reacting phosphorus pentachloride with phosphorus
    pentoxide.  It is used in the manufacture of phosphate esters that are
    used in plasticizers, hydraulic fluids, pesticides, and flame
    retardants, and in the manufacture of several pharmaceuticals.  It is
    also used as a solvent in cryoscopy.

    2.  SUMMARY AND EVALUATION

    2.1  Exposure to Phosphorus Trichloride and Phosphorus Oxychloride

    Exposure to phosphorus trichloride and phosphorus oxychloride occurs
    only during their transport and in the workplace.  The general
    population is exposed only if there is a massive accidental release
    or, exceptionally, an intentional discharge into the air.  These
    substances are not found in the natural environment.

    The pattern of exposure in the workplace is usually irregular,
    resulting from small leaks that volatilize and hydrolyse rapidly in
    the air. Because phosphorus chlorides are transient in the air, they
    are difficult to analyse. Thus, accurate estimates of their exposure
    levels are difficult to obtain.

    The skin, eyes, and respiratory tract can be exposed. However, the
    chemicals are so volatile that they react immediately with the tissues
    and are not usually absorbed systemically.  It is impossible to
    distinguish between exposure to phosphorus chlorides and exposure to
    their hydrolysis products.

    2.2  Fate of Phosphorus Trichloride and Phosphorus Oxychloride

    The very small amounts of phosphorus trichlorides and oxychlorides
    that actually enter the environment react rapidly with water to form
    hydrochloric and phosphorus oxyacids. After deposition, these oxyacids
    are neutralized and/or buffered to form chloride (by oxidation of
    phosphite) and phosphate salts.  The quantities of these chlorides and
    phosphate salts are not significant.

    2.3  Uptake, Metabolism, and Excretion

    Phosphorus trichloride and phosphorus oxychloride react with the water
    component of the tissues they first contact.  The resulting hydrogen
    chloride and phosphorus oxyacid ions, if absorbed, join the body pools
    of these ions. Phosphate, chloride, and hydrogen ions are easily
    excreted by the kidneys by normal physiological mechanisms.

    2.4  Effects on Organisms in the Environment

    Phosphorus trichloride and phosphorus oxychloride hydrolyse by
    reacting 3 moles of water per mole and yielding 6 moles of hydrogen
    ion per mole.  As liquids or in high vapour concentrations, they kill
    most animal and plant tissues they contact. However, the dehydrating
    and acidifying effects of major releases are transient and local.

    2.5  Effects on Animals and Human Beings

    Because of the corrosiveness of both phosphorus trichloride and
    phosphorus oxychloride, many types of toxicological tests cannot
    be done. For phosphorus trichloride, a 4-h LC50 in rats was
    584 mg/m3, and an oral LD50 was 550 mg/kg body weight; a 4-h LC50 in
    guinea-pigs was 281 mg/m3.  For phosphorus oxychloride, 4-h LC50
    values were 301 mg/m3 in rats and 332 mg/m3 in guinea-pigs.  The
    LC50 values should be interpreted with caution because of the
    difficulty in measuring administered concentrations.

    Because of the predominance of local effects of little clinical
    interest, few cases have been reported although the effects on human
    beings are well known.  Contact with the skin can cause severe
    chemical burns with extensive blistering but no charring.  If liquids
    enter the eyes, severe corrosive injury can occur.

    Depending on their concentration, the vapours can be irritating or
    corrosive, but they may be less irritating than their hydrolysis
    products.  However, exposure to the vapours can cause necrosis of the
    tissues of the respiratory tract.  The vapours can be deeply inhaled
    and may reach the lower airways where they hydrolyse to produce
    hydrogen chloride and phosphorous or phosphoric acid.

    Irritation of the airways causes swelling and bronchospasm resulting
    in tightness of the chest, wheezing, and difficulty in breathing. 
    Reactive secretion of mucus causes a cough with sputum and possible
    bronchial obstruction and local lung collapse.

    Severe irritation to the alveolar membrane can cause exudative
    pulmonary oedema with restricted gaseous diffusion and hypoxia, frothy
    blood-tinged sputum, and possible healing by scarring that leaves a
    permanent restrictive defect.

    Permanent or delayed effects, other than scarring at the site of
    contact (including corneal opacity and pulmonary fibrosis) are
    unlikely.  Repeated exposure to levels that are not high enough to
    cause severe immediate symptoms may cause progressive impairment of
    lung function.

    Severe acute overexposure to either compound can rapidly lead to
    death.

    3.  CONCLUSIONS AND RECOMMENDATIONS

    3.1  Conclusions

    Phosphorus trichloride and phosphorus oxychloride are highly reactive
    and hazardous corrosive chemicals.  Intense exposure to their vapours
    may leave a residual restrictive defect in the lungs. Repeated minor
    overexposures may result in progressive impairment of lung function,
    and can be fatal.  Apart from spillages that destroy plant and animal
    life in the immediate area, the impact of these chemicals on the
    environment is negligible.

    3.2  Recommendations

    Phosphorus trichloride and phosphorus oxychloride should only be used
    and handled under the careful supervision of managers who fully
    understand the hazards and the good handling and manufacturing
    practices necessary to control them.  These managers should train
    operators, maintenance personnel, and contractors about the hazards
    and safety procedures.

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

    4.1  Human Health Hazards, Prevention and Protection, First Aid

    The main human health hazards are the severe irritant and corrosive
    effects caused by both the liquids and the vapours of these compounds. 
    The violence of the reaction of phosphorus trichloride or phosphorus
    oxychloride with water, which may be delayed after the first moment of
    contact, can cause splashing.  Accidents can occur if there is
    residual moisture in any of the equipment used for phosphorus
    trichloride or phosphorus oxychloride and when water is used to
    extinguish fires and control spillages.

    4.1.1  Prevention and protection

    Phosphorus trichloride and phosphorus oxychloride should be handled in
    completely enclosed systems.  Warning and information labels should be
    placed on pipes and equipment.  Impervious clothing and gloves, eye
    and face protection, or full-face respiratory protection equipment
    should be used during all operations, including sampling, where there
    is open exposure.  Particular care needs to be taken when pumps,
    pipes, and other equipment used to transfer the liquids are serviced
    or dismantled.  Drums and other containers that hold the liquids must
    be completely dry.  Before opening the drums, ensure that there is no
    water on top.

    4.1.2  First Aid

    The human health hazards, preventive and protective measures, and
    first-aid recommendations, are given in the International Chemical
    Safety Card (section 6).

    4.2  Advice to Physicians

    No specific antidote is known.  Eyes and skin burns should be washed
    with freshly drawn potable water, or with sterile 1% sodium
    bicarbonate solution, if available, and treated conventionally. 
    Patients with severe, extensive burns need fluid replacement. 
    Metabolic acidosis should be treated in a burns unit, and eye injuries
    should be examined by an ophthalmologist as soon as possible.

    Even after a minor exposure to vapours, the patient should be admitted
    to hospital for 24- to 48-h observation, and a chest X-ray taken,
    because there is a chance that pulmonary oedema may develop. 
    Bronchodilators may be given with a nebuliser or in metered-dose
    aerosol form to reduce bronchospasm and dyspnea. If there are
    immediate respiratory symptoms that indicate airway exposure, steroids
    may be given to minimize chemical pneumonitis and scarring. 
    Intravenous methylprednisolone in initial doses up to 30 mg/kg, with
    subsequent smaller doses, or steroids in metered-dose aerosol form at
    several times the normal maintenance dosage, may be given. 
    Prophylactic antibiotic therapy is indicated because secondary
    bacterial infection of the airways is common.

    If pulmonary oedema develops, the patient should remain in a seated
    upright position and be given oxygen.  High doses of intravenous
    methylprednisolone may be more effective than steroids inhaled from
    aerosol. Diuretics, morphine, and theophylline derivatives are of
    little benefit, because the oedema is an exudate rather than a
    transudate due to raised pulmonary capillary pressure. Intermittent
    positive pressure ventilation, combined with bronchial cleansing
    (bronchial toilet) and suction, are additional treatments that can be
    used.

    4.3  Health Surveillance Advice

    It is difficult to measure phosphorus chlorides in the air.  It may be
    easier to collect samples of air in water or in an alkaline buffer, so
    that phosphorus chlorides will be hydrolysed, and then measure the
    total chloride.  Phosphorus trichloride, 1 mg/m3, corresponds to
    about 0.75 mg/m3 chloride; 1 mg/m3 phosphorus oxychloride
    corresponds to about 0.67 mg/m3 chloride.  Exposure limits for the
    total chloride in air derived in this way for exposure limits for
    phosphorus trichloride or phosphorus oxychloride (see the table on
    pages 26 to 28) are within the exposure limit of 7 mg/m3 for
    hydrogen chloride.  These limits are conservative because it was
    assumed that all the Cl- was in the form of the phosphorus chloride.

    It is advisable that people with pre-existing respiratory disease not
    work with respiratory irritants such as phosphorus trichloride and
    phosphorus oxychloride.

    Wherever workers are exposed, or where exposure levels require that
    personal respiratory protection equipment be used, it is advisable to
    measure pulmonary function regularly to ensure that there is no
    abnormal reduction.

    4.4  Explosions and Fire Hazards

    Phosphorus trichloride and phosphorus oxychloride do not burn or
    explode, but when they come in contact with water, they may splash
    over a wide area.  The violent reaction of phosphorus trichloride or
    phosphorus oxychloride with water may ignite other combustible
    materials.  When heated to decomposition, they emit toxic fumes. 
    During fires, containers should be kept cool with water spray BUT ONLY
    IF THERE IS NO RISK OF CONTACT BETWEEN THE PRODUCT AND WATER.

    In emergency situations, a positive pressure-demand/self-contained
    breathing apparatus, with complete chemically resistant clothing,
    should be used, and fire-fighters should wear compressed-air breathing
    apparatus.  For mixed fires, if there is no risk of contact between
    the phosphorus trichloride or phosphorus oxychloride and the
    fire-fighting medium, the medium can be chosen according to the other
    chemicals involved.  Otherwise, dry foam or inert gases should be
    used.

    4.5  Storage

    Phosphorus trichloride and phosphorus oxychloride should be stored in
    properly sealed and labelled drums, or in suitable bulk containers, in
    a cool, dry, well-ventilated place. Drums should be handled carefully
    to prevent puncturing.  Water should not come in contact with the
    material or packaging.  Containers (cylinders, carboys) should be made
    of steel-jacketed lead and tank-cars should be nickel-lined.  Phenol
    resins can be used as an additional lining.  Carbon steel can be used
    for phosphorus trichloride, but not for phosphorus oxychloride.

    4.6  Transport

    If an accident occurs during road transport, stop the engine and
    remain upwind.  If a vapour cloud drifts towards an in-habited area,
    warn the inhabitants and evacuate the areas close to the spillage, if
    this can be done without risking exposure.  If not, instruct people to
    remain indoors with doors, windows, and ventilators closed.

    4.7  Spillage and Disposal

    4.7.1  Spillage

    Liquid spillage should be handled only by trained personnel wearing
    protective clothing and full-face mask/positive-pressure breathing
    apparatus.  The spillage should be absorbed in dry sand or in an inert
    absorbent material and shovelled into sealable polyethylene-lined
    containers for disposal.

    Vapour drifting towards people can be "knocked-down" with water spray.
    Do not wet the spillage itself and never use a water jet on a
    spillage.  When the absorbent medium has been cleared from the ground,
    flush the contaminated area with water until the fumes disappear;
    residues may be neutralized with soda ash (sodium carbonate) or lime.

    If phosphorus trichloride or phosphorus oxychloride enter a
    watercourse or sewer, or contaminate soil or vegetation, warn the
    police and public authorities immediately.

    4.7.2  Disposal

    Spillage should be handled only by an operator wearing full protective
    clothing and full-face mask/positive-pressure breathing apparatus.

    Absorbed spillage and residues should be buried in an approved
    landfill, away from water sources.  Small amounts of spillage can be
    added at intervals to an open tank of water in the open air at a safe
    distance from people.  The water should be neutralized with soda ash
    (sodium carbonate) or lime before disposal in a drain or sewer.

    5.  HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION

    Phosphorus trichloride and phosphorus oxychloride hydrolyse in water
    to form hydrochloric and phosphorous or phosphoric acids.  The toxic
    effects on organisms in the environment depend on the extent to which
    the hydrogen ion is diluted and buffered;  organisms die if they come
    in contact with undiluted material.

    In general, an environmental hazard will occur only in the immediate
    area of a spillage or if disposed of improperly.  Recovery of soil and
    surface waters is rapid and there are no residual effects on the
    environment (see section 4.7).

    6.  INTERNATIONAL CHEMICAL SAFETY CARD

     This card should be easily available to all health workers concerned
     with, and users of, phosphorus trichloride or phosphorus oxychloride. 
     It should be displayed at or near entrances to areas where there is
     potential exposure to phosphorus trichloride or phosphorus
     oxychloride, and on processing equipment and containers.  The card
     should be translated into the appropriate language(s).  All persons
     potentially exposed to the chemicals should 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.


        PHOSPHORUS TRICHLORIDE                         PHOSPHORUS OXYCHLORIDE

    (Phosphorus chloride, Tri; "Pickle")           (Phosphorus oxytrichloride, Oxy; "Pockle")
    (PCl3)                                         (POCl3)
    (CAS Registry No. 7719-12-2)                   (CAS Registry No. 10025-87-3)

                                                                                                                                         

    PHYSICAL PROPERTIES                                                      OTHER CHARACTERISTICS
                                                                                                                                         

                                      Phosphorus         Phosphorus
                                      trichloride        oxychloride

    Relative molecular mass           137.33             153.33              Clear, colourless, strongly fuming liquids,
    Melting point (°C)                -91                2                   with a pungent odour, and a heavy vapour which
    Boiling point (°C)                75.5               107.2               reacts with atmospheric water vapour to produce
    Water solubility                  reacts             reacts              hydrogen chloride that has a relative vapour
    Relative density (21 °C)          1.5                1.6                 density of about 1.25. The liquids react violently
    Relative vapour density           4.77               5.32                with water, sometimes after a quiescent period.
    Vapour pressure                   13.3               5.3                 Both liquids and vapours are corrosive to all
     (kPa) (27.3 °C)                                                         tissues.

                                                                                                                                         

    HAZARDS/SYMPTOMS                        PREVENTION AND PROTECTION                    FIRST AID
                                                                                                                                         

     Vapour/fumes

    EYES: Lacrimation, severe               Use proper containers or efficient           Remove from exposure; irrigate eyes
    irritation, or corrosion.               local exhaust ventilation; otherwise,        for at least 15 min with a gentle flow
                                            a full-face mask/compressed-air              of freshly drawn potable water or, if
                                            breathing apparatus should be worn.          available, sterile sodium bicarbonate
                                                                                         solution or other eye-irrigation fluid;
                                                                                         obtain medical attention.

    INHALATION: Severe irritation,          Use proper containers or efficient           Remove from exposure; if breathing has
    tightness of chest, wheezing,           local exhaust ventilation; otherwise,        stopped, give artificial respiration;
    breathing difficulty, cough,            a full-face mask/compressed-air              maintain airway; keep patient at rest
    air-hunger, blue lips.                  breathing apparatus should be worn.          and, if conscious, seated upright; 
                                                                                         administer oxygen; obtain medical 
                                                                                         attention.

     Liquid

    SKIN: Severe chemical burns.            Use proper containers; do not                FIRST AIDERS MUST PROTECT
                                            contaminate with water; wear impervious      THEMSELVES from skin contact and
                                            overalls, gauntlets, and head and            fumes; remove contaminated clothing
                                            face protection; respiratory                 and throw clear to a dry place
                                            protection may also be required.             downwind; drench the patient in a shower,
                                                                                         keeping away from evolved fumes; clean
                                                                                         affected areas thoroughly; do not burst
                                                                                         blisters; cover with clean wet (water)
                                                                                         dressings; obtain medical attention.

    EYES: Severe chemical burns,            Use proper containers; do not                Remove from exposure; irrigate eyes for
    pain, and lacrimation.                  contaminate with water; wear full head       at least 15 min with a gentle flow of
                                            and face protection; respiratory             freshly drawn potable water, sterile
                                            protection may also be required.             sodium bicarbonate solution, or other
                                                                                         sterile eye-irrigation fluid; obtain
                                                                                         medical attention.

                                                                                                                                         

    HAZARDS/SYMPTOMS                        PREVENTION AND PROTECTION                    FIRST AID
                                                                                                                                         

    INGESTION: Severe burns to              Do not eat, drink, or smoke while            Rinse mouth with sodium bicarbonate
    mouth, throat, and oesophagus;          handling chemicals.                          solution or water; do not induce
    abdominal pain.                                                                      vomiting; obtain medical attention.

                                                                                                                                         
    
    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.

    Regulatory decisions about chemicals taken in a certain country can be
    fully understood only in the framework of that country's legislation.
    Therefore, they should always be verified with the appropriate
    authorities.

    There are restrictions, limitations, and safety precautions in some of
    the countries where phosphorus trichloride and phosphorus oxychloride
    have been registered. They should always be consulted before these
    substances are used.

    A full reference to the original national document from which the
    information was extracted can be obtained from IRPTC.  When no
    effective date appears in the IRPTC legal file, the year of the
    reference from which the data are taken is shown, indicated by (r).

    7.1  Exposure Limit Values

    Some exposure limit values are given on the following pages.

    7.2  Specific Restrictions

    In the USA, phosphorus trichloride is classified as a hazardous waste
    and as a hazardous pollutant.

    The USA also classifies phosphorus oxychloride as a hazardous
    substance for water pollution.  When used in pesticides, it is exempt
    from tolerance requirements in plant and meat products.  Kenya permits
    its use as a starch-modifying food additive.

    7.3  Labelling, Packaging, and Transport

    The European Community Legislation requires labelling of phosphorus
    trichloride and phosphorus oxychloride as corrosive.


        EXPOSURE LIMIT VALUES

                                                                                                                                         

    Medium    Specification    Country/         Exposure limit description                           Value                    Effective
                               organization                                                                                   date
                                                                                                                                         

                                                                                           Phosphorus       Phosphorus
                                                                                           Trichloride      Oxychloride

    AIR       Occupational     Australia        Threshold limit value (TLV)                                                   1983(r)
                                                - Time-weighted average (TWA)              1.5 mg/m3             -
                                                - Short-term exposure limit (STEL)         3 mg/m3               -

                               Belgium          Threshold limit value (TLV)                                                   1987/
                                                - Time-weighted average (TWA)              1.5 mg/m3        0.6 mg/m3         1984(r)
                                                - Short-term exposure limit (STEL)         3 mg/m3          3 mg/m3

                               Bulgaria         Maximum allowable concentration (MAC)                                         1987
                                                - Ceiling value                            0.2 mg/m3             -

                               Finland          Maximum permissible concentration (MPC)                                       1982/
                                                - Short-term exposure limit (STEL)         3 mg/m3          3 mg/m3           1985(r)

                               Germany,         Maximum permissible concentration (MPC)                                       1987(r)
                               Democratic       - Short-term exposure limit (STEL)              -           1 mg/m3
                               Republic of

                               Germany,         Maximum work-site concentration                                               1987(r)
                               Federal          - Time-weighted average (TWA)              3 mg/m3          1 mg/m3
                               Republic of      - Short-term exposure limit (STEL)         6 mg/m3          2 mg/m3
                                                  (5 min, 8 x/shift)

                               Hungary          Maximum allowable concentration (MAC)                                         1978(r)
                                                - Time-weighted average (TWA)              1 mg/m3               -
                                                - Short-term exposure limit (STEL)         2 mg/m3               -
                                                  (30 min)

                                                                                                                                         

    Medium    Specification    Country/         Exposure limit description                           Value                    Effective
                               organization                                                                                   date
                                                                                                                                         

                                                                                           Phosphorus       Phosphorus
                                                                                           Trichloride      Oxychloride

                               Italy            Threshold limit value (TLV)                                                   1986/
                                                - Time-weighted average (TWA)              2 mg/m3          1 mg/m3           1985(r)
                                                  (provisional)

                               Netherlands      Maximum limit (MXL)                                                           1987/
                                                - Time-weighted average (TWA)              1.5 mg/m3        0.6 mg/m3         1986(r)

                               Romania          Maximum permissible concentration (MPC)                                       1985/
                                                - Time-weighted average (TWA)              2 mg/m3          2 mg/m3           1975(r)
                                                - Ceiling value (CLV)                      5 mg/m3          5 mg/m3

                               Switzerland      Maximum work-site concentration (MAK)                                         1987(r)
                                                - Time-weighted average (TWA)              1.5 mg/m3        0.6 mg/m3

                               United           Occupational Exposure Standard                                                1989(r)
                               Kingdom          - Time-weighted average (TWA)              1.5 mg/m3        1.2 mg/m3
                                                - Short-term exposure limit (STEL)         3 mg/m3          3.6 mg/m3
                                                  (10-min time-weighted average)

                               USA              Threshold limit value (TLV)                                                   1987(r)
                               (ACGIH)          - Time-weighted average (TWA)              1.5 mg/m3        0.6 mg/m3
                                                - Short-term exposure limit (STEL)         3 mg/m3          3 mg/m3

                               USA              Permissible exposure limit (PEL)                                              1986(r)
                               (OSHA)           - Time-weighted average (TWA)              3 mg/m3               -
                                                - Immediately Dangerous to Life and        300 mg/m3             -
                                                  Health (IDLH)

                               USSR             Maximum allowable concentration (MAC)                                         1977
                                                - Ceiling value                            0.2 mg/m3        0.05 mg/m3

                                                                                                                                         

    Medium    Specification    Country/         Exposure limit description                           Value                    Effective
                               organization                                                                                   date
                                                                                                                                         

                                                                                           Phosphorus       Phosphorus
                                                                                           Trichloride      Oxychloride

                               Yugoslavia       Maximum allowable concentration (MAC)                                         1971(r)
                                                - Time-weighted average (TWA)              3 mg/m3          1 mg/m3

    WATER     Surface          USSR             Maximum allowable concentration (MAC)      0.1 mg/               -            1978(r)
                                                (surface water for fishing)                litre

    FOOD                       FAO/WHO          No acceptable daily intake (ADI)                                              1982(r)
                                                allocated

                                                                                                                                         
    


    The label must read as follows:

          Corrosive, causes burns, irritating to respiratory system.  Keep
          container tightly closed and dry.  In case of contact with eyes,
          rinse immediately with plenty of water and seek medical advice.

    The following symbol should be used:

    FIGURE 1

    In the United Kingdom, road tankers transporting phosphorus
    trichloride or phosphorus oxychloride must be labelled "Corrosive
    Substance".

    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 CHEMICAL INDUSTRY ASSOCIATION  (1980)  Handling chemicals
     safely. 2nd ed. Dutch Association of Safety Experts, Dutch Safety
    Institute.

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

    IARC (1974)  IARC monographs on the evaluation of carcinogenic risk of
     chemicals to man: some aromatic amines, hydrazine and related
     substances, N-nitroso compounds and miscellaneous alkylatry agents,
    Vol. 4, Lyon, International Agency for Research on Cancer.

    IRPTC (1988)  Data profile (legal 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 Administration (Publication No.
    85.114).

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

    US DHHS (NIOSH) (1987)  Registry of Toxic Effects of Chemical
     Substances. Washington DC, US Department of Health and Human
    Services, Public Health Service, Centers for Disease Control, National
    Institute for Occupational Safety and Health, 5 Vols (DHSS/NIOSH:
    Publication No. 87-114)

    


    See Also:
       Toxicological Abbreviations