<b>Bijsluiter</b>. De hyperlink naar het originele document werkt niet meer. Daarom laat Woogle de tekst zien die in dat document stond. Deze tekst kan vreemde foutieve woorden of zinnen bevatten en de opmaak kan verdwenen of veranderd zijn. Dit komt door het zwartlakken van vertrouwelijke informatie of doordat de tekst niet digitaal beschikbaar was en dus ingescand en vervolgens via OCR weer ingelezen is. Voor het originele document, neem contact op met de Woo-contactpersoon van het bestuursorgaan.<br><br>====================================================================== Pagina 1 ======================================================================

<pre>Thallium and water-soluble thallium
compounds
Health-based Reassessment of Administrative
Occupational Exposure Limits
Committee on Updating of Occupational Exposure Limits,
a committee of the Health Council of the Netherlands
No. 2000/15OSH/057, The Hague, 31 October 2002
</pre>

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<pre>Preferred citation:
Health Council of the Netherlands: Committee on Updating of Occupational
Exposure Limits. Thallium and water-soluble thallium compounds;
Health-based Reassessment of Administrative Occupational Exposure Limits.
The Hague: Health Council of the Netherlands, 2002; 2000/15OSH/057.
all rights reserved
</pre>

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<pre>1     Introduction
      The present document contains the assessment of the health hazard of thallium
      and water-soluble thallium compounds by the Committee on Updating of
      Occupational Exposure Limits, a committee of the Health Council of the
      Netherlands. The first draft of this document was prepared by MA Maclaine
      Pont, M.Sc. (Wageningen University, Wageningen, the Netherlands).
          The evaluation of the toxicity has among others been based on a review by
      the World Health Organization/International Programme on Chemical Safety
      (WHO/IPCS) (WHO96). Data considered to be critical were evaluated by
      reviewing the original publications. In addition, literature was retrieved from the
      databases Medline, Toxline, and Chemical Abstracts covering the periods 1993
      until February 1998, 1987 until October 1997, and 1992 until December 1997,
      respectively. The literature search was concentrated on those thallium
      compounds which are very soluble and soluble in water, according to the
      Handbook of Chemistry and Physics (Lid96), and the following key words were
      used: thallium, 563-68-8, 992-98-3, 1314-12-1, 7440-28-0, 7789-27-7,
      10102-45-1, 12026-06-1, 13453-32-2, 13453-34-4, 13453-40-2, 13701-90-1,
      and 13826-63-6. The final search was carried out in February 1998.
          In December 1998, the President of the Health Council released a draft of
      the document for public review. The committee received no comments.
          Additional literature searches in May 1999 and May 2002 did not result in
      information changing the committee’s conclusions.
057-3 Thallium and water-soluble thallium compounds
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<pre>2             Identity
name                              molecular formula     synonyms                                                 CAS number
thallium                          Tl                    Ramor                                                    7440-28-0
thallium(I) acetate               TlC2H3O2              acetic acid, thallium(I) salt; thallous acetate          563-68-8
thallium(I) cyanide               TlCN                  thallous cyanide                                         13453-34-4
thallium(I) fluoride              TlF                   thallous fluoride                                        7789-27-7
thallium(I) formate               TlCHO2                formic acid, thallium(1+) salt                           992-98-3
thallium(I) hydroxide             TlOH                  thallous hydroxide                                       12026-06-1
thallium(I) nitrate               TlNO3                 nitric acid, thallium(1+) salt; thallous nitrate         10102-45-1
thallium(I) nitrite               TlNO2                 nitrous acid, thallium(1+) salt                          13826-63-6
thallium(I) oxide                 Tl2O                  thallous oxide                                           1314-12-1
thallium(I) perchlorate           TlClO4                perchloric acid, thallium(1+) salt                       13453-40-2
thallium(III) bromide             TlBr3.4H2O                                                                     13701-90-1
tetrahydrate
thallium(III) chloride            TlCl3                                                                          13453-32-2
thallium(III) chloride            TlCl3.4H2O                                                                     13453-32-2
tetrahydrate
a
      The presence of an asterisk following a CAS number indicates that the registration is for a substance that CAS does not
      treat in its regular CA index processing as a unique chemical entity.
              Thallium (Tl) is a heavy metal, with a natural abundance of approximately 0.7
              ppm (Bud96).
                    Forty-seven isotopic forms of thallium, with atomic masses ranging from
              179 to 210 are recognised. The half-life of the unstable isotopes ranges from
              0.06 sec to 3.78 years. Natural thallium is a mixture of two isotopes: 203Tl and
              205
                  Tl (Lid96).
              In contrast to the small world production of about 10-15 tonnes thallium per
              year, the amount of thallium in waste material is estimated to be about 600
              tonnes per year (Kem91).
057-4         Health-based Recommended Occupational Exposure Limits
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<pre>3          Physical and chemical properties
name              physical form                     mol weight solubility in water melting point boiling point
                                                                                        o
Tl                soft blue-whitish metal           204.38     insoluble           304 C         1473oC
                                                                                        o
TlCHO2            hygroscopic colourless needles    249.4      very soluble        101 C         -
TlOH              yellow needles                    221.39     very soluble        139oC,        -
                                                                                   decomposes
TlNO2             cubic crystals                    250.39     very soluble        -             -
                                                                                        o
TlCl3             monoclinic crystals               310.74     very soluble        155 C         -
TlC2H3O2          hygroscopic white crystals        263.43     soluble             131oC         -
TlCN              white hexagonal plates            230.4      soluble             -             -
TlF               white orthorhombic crystals       223.38     soluble             326oC         826oC
                                                                                        o
TlNO3             white crystals                    266.39     soluble             206 C         450oC,
                                                                                                 decomposes
Tl2O              black hygroscopic rhombohedral    424.77     soluble             579oC         ca. 1080oC
                  crystals
TlClO4            colourless orthorhombic crystals  303.83     soluble             -             -
TlBr3.4H2O        yellow orthorhombic crystals      516.16     soluble             -             -
TlCl3.4H2O        orthorhombic crystals             382.8      soluble             -             -
           Data from Lid96
           The only vapour pressure found was for thallium: 0.13 kPa at 825oC. All other
           compounds are expected to have a low vapour pressure. Therefore, conversion
           factors for the concentration in air are not applicable; the concentration can only
           be expressed in mg/m3.
               Further, no data on flash point, explosion limits, or log Poctanol/water values
           were found.
               Thallium oxidises in air to form a superficial layer of Tl2O. It forms alloys
           with other metals and readily amalgamates with mercury (ACG91). Thallium is
           flammable; it should therefore be kept under water. It reacts violently with
           peracetic acid and halogens, with a risk of fire and explosion (Che98).
               Solutions of thallous fluoride and thallous hydroxide are strongly alkaline.
           On exposure to air thallous oxide gradually oxidises to thallic oxide, becoming
           insoluble in water (Bud96).
057-5      Thallium and water-soluble thallium compounds
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<pre>4     Uses
      Thallium is used in the semiconductor industry and is alloyed with mercury in
      some switches. In addition, it is used in mineralogical solutions, optical systems,
      photoelectric cells, and low-range glass thermometers (ACG91).
           201
               Thallium is widely used in myocardial imaging (Bel94).
           Thallous cyanide is used in organic synthesis; thallous fluoride in the
      preparation of fluoro esters; thallous nitrate as a reagent in analytical chemistry,
      especially for the determination of iodine in the presence of Br and Cl. Thallous
      oxide is used in the manufacturing of glass with a high coefficient of refraction
      for optical purposes (thallium flint glass) and for artificial gems (Bud96).
5     Biotransformation and kinetics
      Human data
      Thallium is rapidly absorbed (up to 80-100%) by the mucous membranes, after
      ingestion, inhalation, or contact with intact skin. A rapid distribution from blood
      to tissue follows absorption. Because of the similar ionic radii of thallium (I)
      and potassium, thallium can substitute for potassium in a variety of
      potassium-dependent transport processes such as the ‘active transport’ and,
      consequently, accumulate intracellularly. In humans, thallium is found to
      accumulate in kidneys, muscles, certain brain areas, and testicles (Kem91).
           Examination of a population living in Germany near a cement plant with
      thallium emission and of workers of that plant has been done over the period
      1979-1981. The frequency distributions of thallium content in blood, urine, and
      hair samples of 1980/81 showed a shift to higher values compared with those of
      unaffected areas. Nevertheless, the range of all results is distinctly different
      from the thallium concentrations in body fluids and hair found in acute thallium
      intoxications. Moreover, no individual result reached the urinary thallium level
      of 300 µg/L, suggested as the threshold value for factory workers (Kem91).
      Analysis of liver and kidney tissue obtained from autopsied dead individuals
      (54 males, 16 females; 18-76-year old) from the North Bohemia territory of the
      Czech Republic showed median levels of thallium of 0.5 µg/kg wet tissue
      weight (geometric mean: 1 µg/kg; range: 0.5-110 and 0.5-5.5 µg/kg for liver
      and kidney, respectively) (Ben00).
057-6 Health-based Recommended Occupational Exposure Limits
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<pre>          In working environments, exposure via inhalation and skin contact has also
      been reported. For inhabitants of an emission region of a coal-fired power plant,
      a daily thallium intake by ingestion and inhalation of 0.15-0.18 µg/kg body
      weight has been calculated (Kem91). From the UK 1994 Total Diet Study, a
      total dietary intake of thallium of 2 µg/day has been estimated (Ysa99).
          Increased levels of thallium have been observed in the lungs of coal miners,
      but no data are available concerning the absorption of thallium salts after
      inhalation exposure. Generally, it is assumed that about 35% of respirable dusts
      is deposited in the lung and that up to 100% of the deposited thallium is
      absorbed (WHO96).
          Quantitative data on penetration through the skin, expressed as mg Tl/cm2 of
      skin per hour, were not found (Bel94, Hos93, Kem91, WHO96).
          The toxicokinetics of thallium in humans are described by a 3-compartment
      model. The first phase, which lasts about 4 hours, represents intravascular
      distribution. The second phase lasts 4-48 hours during which thallium is
      distributed into the central nervous system. In general, the distribution phase is
      completed within about 24 hours. The elimination phase starts about 24 hours
      after ingestion and its duration depends on the therapeutic intervention used
      (Ano93).
          Thallium can pass the placenta and be excreted in breast milk (Hof00,
      WHO96).
          The myocardial clearance of 201Tl, after intravenous injection into 15
      volunteers, while exercising, was 13% per hour. There are no further data
      (Lee94).
          The excretion of thallium in humans differs from that in laboratory animals,
      since the rate of excretion is generally much lower in humans (rate constant:
      0.023-0.069 per day) than in laboratory animals (average rate constant: 0.18 per
      day) (WHO96).
          Half-life times for elimination in man have been reported to range between
      1.7 and 30 days, depending on the time since, and chronicity of, ingestion
      (Ano93) and 9 and 11 days, based on urinary thallium contents after accidental
      or suicidal ingestion (Kem91).
          Another major difference between humans and animals is the relative
      contribution of the different routes of excretion. In humans, renal excretion
      seems to be much more important than in animals. In one study, urinary
      excretion of thallium was ±73%, whereas the gastrointestinal excretion was
      3.7%. Excretion through hair and skin, and sweat has been estimated to be
      19.5% and 3.7%, respectively (WHO96). However, others report that faecal
057-7 Thallium and water-soluble thallium compounds
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<pre>      excretion is more important than urinary excretion (Ano93, Bel94, Kem91). It
      probably depends on the status of the patient, the dose taken up, the quantity of
      potassium present, and the time of measurement.
          Faeces, urine, and hair samples may serve as indicator specimens in chronic
      exposure to small amounts of thallium. Concentrations of up to 2 µg Tl/L in
      whole blood and up to 5 µg/L urine may be considered as normal (Kem91).
          Others, however, propose different reference values: 0.5 µg Tl/L blood, 0.5
      µg Tl/L plasma for non-occupationally exposed individuals, based on the
      concentration of thallium found in blood of healthy donors in the UK (n=ca.
      2620) (Ham94). When the concentration data of thallium found in the blood of
      123 healthy inhabitants of Central Italy are taken, a reference interval is
      proposed of 0.014-0.19 µg Tl/L blood (Sab94). For urine, these numbers are:
      0.5 µg Tl/L (Ham94), and 0.019-0.17 µg Tl/L (Sab94).
      Animal data
      Using different routes of administration of a thallous nitrate solution (oral,
      subcutaneous, intramuscular), thallium was rapidly and almost completely
      absorbed in rats. No effect of the route of administration on distribution was
      observed (WHO96). After intravenous injection, an initial increase in the
      thallium concentration of the blood is followed by a steep decrease within 5 to
      15 minutes. A similar trend is observed after oral administration of thallium to
      rats (WHO96). Thallium is rapidly distributed to all organs and passes the
      placenta. Because of its rapid accumulation in cells, concentrations of thallium
      in whole blood do not reflect the levels in tissues. In acute poisoning of
      experimental animals or humans, initially high concentrations of thallium
      appear in the kidney, low concentrations in fat tissue and brain, and
      intermediate concentrations in the other organs; later, the thallium concentration
      of the brain also increases (WHO96). In rats, the main routes of elimination are
      gastrointestinal (about two thirds) and renal (about one third); in rabbits, the
      contribution of the 2 routes is about equal (WHO96).
6     Effects and mechanism of action
      Human data
      Thallium poisoning is accompanied with a range of symptoms in humans that
      are usually non-specific because of the multi-target organ toxicity involved. The
057-8 Health-based Recommended Occupational Exposure Limits
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<pre>      initial symptoms of thallium poisoning may include fever, gastrointestinal
      problems, delirium, convulsions, and coma. Symptoms may appear rapidly but
      more commonly, the acute toxicity subsides and is replaced by a gradual
      development of mild gastrointestinal disturbances, polyneuritis, encephalopathy,
      tachycardia, skin eruptions, stomatitis, atrophic changes of the skin, nail
      changes, and skin hyperaesthesia. Degenerative changes of the heart, liver, and
      kidney, subarachnoid haemorrhage, bone marrow depression, and increased
      radiopacity of the liver may also occur. Psychotic behaviour with hallucinations
      and dementia has been reported. Alopecia is the most characteristic sign of
      toxicity in humans (Bel94).
           Most cases of thallium toxicity occur after oral ingestion but severe toxicity
      has been reported after inhalation of contaminated dust from pyrite burners in
      zinc and lead smelting and in the manufacture of cadmium (Ano93).
           Thallium intoxication is considered one of the most frequent causes of
      intentional or accidental human poisoning.
           The lowest oral dose of thallium found to induce toxicity in humans was 5.7
      mg/kg bw. It induced effects on the peripheral nervous system, eyes, and skin
      (Lew92). The lowest lethal dose in a human being was 4.4 mg/kg bw (route of
      exposure not given) (Lew92). The lowest lethal oral dose of thallous acetate
      was 12 mg/kg bw (9.3 mg Tl/kg bw) (Lew92). Others concluded that a dose of
      1.0 g/bw of soluble thallium salts (14-15 mg Tl/kg bw) could considered to be
      the lowest dose causing mortality (Bel94).
           Studies of long-term exposure to thallium resulting in chronic poisoning
      have been summarised, without any information about doses. Depending on the
      level of exposure, a relatively long latent period (several weeks) may be
      followed by just a few symptoms. Peripheral sensorial disturbances, mental
      aberrations, loss of weight, and sleeplessness seem to be the most common
      symptoms (WHO96).
           Limited data are available on the effects of thallium on human reproduction.
      Menstrual cycle, libido, and male potency may be adversely affected. Effects on
      sperm are known to occur following chronic intoxication. However, apart from
      a relatively low weight and alopecia of newborn babies, fetal development was
      not affected in about 20 cases of thallium intoxication during pregnancy. There
      are no quantitative data (WHO96). In a recent review on the outcome of
      pregnancy in thallium-poisoned women, 25 cases were identified, 7 of which
      were not included because they did not describe maternal of fetal outcome. In 5
      out of the remaining 18 cases, thallium exposure was in the first trimester, in 5
      in the second, and in 8 in the third trimester. Maternal toxicity consisted of the
057-9 Thallium and water-soluble thallium compounds
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<pre>       classical signs and symptoms of thallium poisoning while fetal effects ranged
       from severe toxicity with residual sequelae to outwardly normal development.
       Some newborns appeared normal despite severe maternal toxicity. The only
       consistent effect identified was a trend toward prematurity and low birth weight
       in children exposed to early gestation. A case of maternal thallium poisoning
       during the first trimester of pregnancy resulting in fetal demise initiated this
       review (Hof00).
           Occupational exposure of 51 (former) Soviet Union workers to more than
       0.01 mg Tl/m3, for 16 to 17 years, caused disorders of the vascular system, as
       well as neurological symptoms. However, there were no detailed data available,
       the author only summarised the study without reference to the original data
       (Ohn85). On the other hand, in another study, there were no statistically
       significant differences in cardiovascular or gastrointestinal effects in a cohort of
       86 exposed workers compared with 79 unexposed controls in a factory of
       magnesium seawater batteries. Exposure to thallium was in the form of fume
       from alloying in the furnaces, skin contact in the strip-rolling of the
       thallium-magnesium alloy, and as a dust generated in the scrap-brushing of the
       alloy (Mar85).
           In a group of persons, living near a thallium atmospheric emission source, a
       clear dose-response relationship was found between urinary thallium
       concentration and the prevalence of several neurological symptoms. However,
       in a group of cement plant workers, no such relationship was found (WHO96).
       Animal data
       Data on acute, single dose toxicity of some water-soluble thallium compounds
       are presented in Table 1.
       When rats were given daily dietary doses of 0.45 mg thallous acetate/kg bw
       (equals 0.34 mg Tl/kg) for up to 4 months, only alopecia was noted after 6
       weeks. At 4 months, there was elevated mortality (ACG91, study from 1928).
           Four groups of 5 male and 5 female rats were placed on a basal diet
       containing 0, 0.0005, 0.0015, and 0.005% thallous acetate, for 15 weeks. Two
       additional groups of rats were added to this study several weeks later; they
       received 0 and 0.003% thallous acetate in their diet. At 0.005%, all animals died
       within 14 days. At 0.003%, increased mortality was observed and growth
       depression after 30 days. The only major finding on gross autopsy was
       moderate to marked alopecia in the rats fed 0.0015% and higher. After 15
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<pre>       weeks, no histological changes were observed in any of the organs examined
       (heart, lung, liver, kidney, spleen, stomach, brain, testes, adrenals, bone marrow,
       femur, and spinal cord). There was no apparent difference between thallium
       administrated as the readily soluble thallous acetate and thallium administered
       as the relatively insoluble thallic oxide (Dow60). It can be concluded that
       feeding rats with 0.0005% thallous acetate for 15 weeks does not lead to any
       effects.
       Carcinogenicity
       The Commission of the European Communities could not classify thallium
       metal, thallic oxide, and thallium sulphate with respect to its (potential)
       carcinogenicity because of the absence of experimental animal, epidemiological,
       and mutagenicity and genotoxicity data. However, these compounds are
       extremely toxic and probably therefore, no need for further work was indicated
       by the Commission (Are93).
        Table 1 Acute lethal toxicity data of some water-soluble thallium compounds (Lew92, WHO96).
        species            thallium compound route             resultsa
        rabbit             TlC2H3O2                oral        LDlo: 24.5 mg/kg bw (19 mg Tl/kg bw)
        dog                                        oral        LDlo: 13 mg /kg bw (10 mg Tl/kg bw)
        dog                                        oral        LDlo: 25.8 mg/kg bw (20 mg Tl/kg bw)
        guinea pig                                 oral        LDlo: 15.5 mg/kg bw (12 mg Tl/kg bw)
        rat                                        oral        LD50: 41.3 mg/kg bw (32 mg Tl/kg bw)
        mouse                                      oral        LD50: 35 mg/kg bw (27 mg Tl/kg bw)
        rabbit                                     intravenous LDlo: 26 mg/kg bw (20 mg Tl/kg bw)
        rat                TlF                     oral        LDlo: 50 mg/kg bw (46 mg Tl/kg bw)
        dog                TlNO3                   oral        LDlo: 45 mg/kg bw (35 mg Tl/kg bw)
        mouse                                      oral        LD50: 33 mg/kg bw (25 mg Tl/kg bw)
        dog                                        intravenous LDlo: 15 mg/kg bw (11.5 mg Tl/kg bw)
        rabbit                                     intravenous LDlo: 14 mg/kg bw (10.7 mg Tl/kg bw)
        rat, fed a low                             intravenous LD50: 16.3 mg/kg bw (12.5 mg Tl/kg bw)
        K+-diet
        rat, fed a high                            intravenous LD50: 18.9 mg/kg bw (14.5 mg Tl/kg bw)
        K+-diet
        a
               LDlo : lowest lethal dose reported.
057-11 Thallium and water-soluble thallium compounds
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<pre>       Mutagenicity and genotoxicity
       Thallium was reported to induce chromosomal aberrations in CHO cells and
       human lymphocytes and to inhibit DNA formation in bone marrow cells of mice
       (only abstract available) (Cui88).
           Thallous acetate was negative in 2 separate bacterial mutagenicity tests
       using S. typhimurium strains TA98, TA1535, TA1537, and TA1538 at
       concentrations of 0.0031-29.2 thallium/plate (no information on metabolic
       activation) and in strains TA98, TA100, TA1535, TA1537, and TA1538 with
       and without metabolic activation (concentrations no reported), respectively
       (WHO96). It enhanced virus-induced cell transformation in cultured hamster
       embryo cells (ACG91).
           Thallous nitrate was positive in the rec assay in B. subtilis indicating that it
       may induce DNA damage but negative in subsequent bacterial mutation assays
       in S. thyphimurium strains TA98, TA100, TA1535, TA1537, and TA1538 and
       E. coli strain WP2 and B/r WP2 (only tested without metabolic activation)
       (Kan80).
       Reproduction toxicity
       Oral administration of doses of thallous acetate or of the slightly soluble
       thallous chloride of 3 or 6 mg/kg bw/day to NMRI mice on gestation days 6-15
       had no observable effects on skeleton or organs at gestation day 18. The high
       dose caused a weight reduction in the embryos. Doses of thallous acetate of 4.5
       mg/kg bw given to rats according to a similar regimen were lethal to the dams
       while doses of 3 mg/kg bw induced malformations of ribs and vertebrae and a
       slight increase in mortality during the first 3 weeks after birth (WHO96).
7      Existing guidelines
       The current administrative occupational exposure limit (MAC) for thallium and
       water-soluble compounds in the Netherlands is 0.1 mg/m3, 8-hour TWA, with a
       skin notation.
           Existing occupational exposure limits for thallium and water-soluble
       thallium compounds in some European countries and in the USA are
       summarised in the annex.
057-12 Health-based Recommended Occupational Exposure Limits
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<pre>8      Assessment of health hazard
       A wealth of human data is available, especially on incidental poisoning. There
       are several ‘lowest doses’ reported, the lowest of them being 4.4 mg Tl/kg body
       weight, which was lethal to a human being.
           Long-term occupational exposure data are contradictory. On the one hand,
       0.01 mg/m3 is said to cause vascular and neurological disorders (Ohn85),
       whereas others report that occupational exposure to 0.1 mg/m3 is without effects
       (Mar85), and, therefore, these human data cannot be used for the risk
       assessment.
           The best available long-term animal study is the 15-week feeding study with
       thallous acetate (Dow60). The critical effect is alopecia, observed in rats fed
       0.0015% and higher. The lowest dose tested, 0.0005%, was a no observed
       adverse effect level (NOAEL). The authors estimated the total intake for a rat
       fed 0.0015% to be approximately 0.3 mg thallous acetate per day. According to
       the authors, this is equivalent to a dose ranging from 1 to 3 mg/kg bw/day,
       depending on the body weight of the rats. Therefore, rats fed 0.0005% thallous
       acetate received a dose of approximately 0.3-1 mg/kg bw/day that is equivalent
       to 0.23-0.78 mg Tl/kg bw/day. The committee takes the mid dose of 0.5 mg
       Tl/kg bw/day as a starting point for deriving a health-based recommended
       occupational exposure limit (HBROEL). For the extrapolation to a HBROEL, a
       factor of 4 for the allometric scaling from rat to man, based on caloric demand,
       and an overall factor of 27 covering inter- and intraspecies variation and
       differences between experimental conditions and the exposure pattern of the
       worker are applied resulting in an NAEL for humans of 0.0046 mg/kg bw/day.
       Assuming a 70-kg worker inhales 10 m3 of air during an 8-hour working day
       and a retention of 100%, and applying the preferred value approach, a
       health-based occupational limit of 0.02 mg/m3 is recommended for thallium and
       its water-soluble compounds.
       The committee recommends a health-based occupational exposure limit of 0.02
       mg/m3 for elemental thallium and its water-soluble compounds, as an 8-hour
       time-weighted average (TWA). Since there are many reports indicating that
       thallium can pass the skin, the committee recommends a skin notation.
057-13 Thallium and water-soluble thallium compounds
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<pre>       References
ACG91  American Conference of Governmental Industrial Hygienists (ACGIH). Thallium, elemental and
       soluble compounds. In: Documentation of the threshold limit values and biological exposure indices.
       6th ed. Cincinnati OH, USA: ACGIH, 1991: 1534-7.
ACG02a American Conference of Governmental Industrial Hygienists (ACGIH). Guide to occupational
       exposure values -2002. Cincinnati OH, USA: ACGIH, 2002: 125.
ACG02b American Conference of Governmental Industrial Hygienists (ACGIH). 2002 TLVs® and BEIs®.
       Threshold Limit Values for chemical substances and fysical agents. Biological Exposure Indices.
       Cincinnati OH, USA: ACGIH, 2002: 57.
Ano93  Anonymous. Thallium poisoning. Br Med J 1993; 306: 1527-9. Mistake: Br Med J 306: 1603.
       Comment: Br Med J 307: 324.
Arb00a Arbejdstilsynet. Grænseværdier for stoffer og materialer. Copenhagen, Denmark: Arbejdstilsynet,
       2000; (At-vejledning C.0.1).
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057-16 Health-based Recommended Occupational Exposure Limits
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<pre>             Annex
Occupational exposure limits for thallium and water-soluble thallium compoundsa in various countries.
country                              occupational exposure         time-weighted      type of exposure noteb   referencec
-organisation                        limita                        average            limit
                                     ppm         mg/m3
the Netherlands
-Ministry of Social Affairs          -           0.1               8h                 administrative   S       SZW02
and Employment
Germany
-AGS                                 -           0.1d              8h                                          TRG00
                                     -           0.4d              15 min
-DFG MAK-Kommission                  -           -e                                                            DFG02
Great-Britain
-HSE                                 -           0.1               8h                 OES              S       HSE02
Sweden                               -           -                                                             Arb00b
Denmark                              -           0.1               8h                                  S       Arb00a
USA
-ACGIH                               -           0.1               8h                 TLV              S       ACG02b
-OSHA                                -           0.1               8h                 PEL              S       ACG02a
-NIOSH                               -           0.1               10 h               REL              S       ACG02a
European Union
-SCOEL                               -           -                                                             CEC00
a
     As thallium.
b
     S = skin notation, which means that skin absorption may contribute considerably to body burden; sens = substance can
     cause sensitisation.
c
     Reference to the most recent official publication of occupational exposure limits.
d
     Inhalable fraction.
e
     Listed among compounds for which studies of the effects in man or experimental animals have yielded insufficient
     information for the establishment of MAK values.
057-17       Thallium and water-soluble thallium compounds
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<pre>057-18 Health-based Recommended Occupational Exposure Limits</pre>

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