<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>Silicon
(CAS No: 7440-21-3)
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/054, The Hague, 31 October 2002
</pre>

====================================================================== Einde pagina 1 =================================================================

<br><br>====================================================================== Pagina 2 ======================================================================

<pre>Preferred citation:
Health Council of the Netherlands: Committee on Updating of Occupational
Exposure Limits. Silicon; Health-based reassessment of current administrative
occupational exposure limits in the Netherlands. The Hague: Health Council of
the Netherlands,2002; 2000/15OSH/054.
all rights reserved
</pre>

====================================================================== Einde pagina 2 =================================================================

<br><br>====================================================================== Pagina 3 ======================================================================

<pre>1     Introduction
      The present document contains the assessment of the health hazard of silicon 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).
           Literature was retrieved from the databases Medline, Toxline, and Chemical
      Abstracts covering the periods 1966 until May 1999, 1981 until April 1999, and
      1937 until April 1999, respectively, and using the following key words: silicon
      or 7440-21-3 (and (toxic*) not (silicone or silicon dioxide). The search for
      toxicological data on elemental silicon was hampered by a wealth of studies on
      silicon compounds, silica, silicones, silanes, using the entry silicon in their list
      of control terms, even using the CAS registry number for the elemental silicon.
           In February 1999, the President of the Health Council released a draft of the
      document for public review. The committee received no comments.
           An additional literature search in May 2002 did not result in information
      changing the committee’s conclusions.
2     Identity
       name                 :     silicon
       synonyms             :     -
       atomic formula       :     Si
       CAS number           :     7440-21-3
      Natural silicon contains 3 isotopes. Fourteen other radioactive isotopes are
      recognised. Silicon makes up 25.7% of the earth’s crust, by weight, and is the
      second most abundant element, being exceeded only by oxygen. Silicon is not
      found free in nature, but occurs chiefly as the oxide and as silicates. Silicon is
      prepared commercially by heating silica and carbon in an electric furnace, using
      carbon electrodes. Several other methods can be used for preparing the element
      (Lid96).
054-3 Silicon
</pre>

====================================================================== Einde pagina 3 =================================================================

<br><br>====================================================================== Pagina 4 ======================================================================

<pre>3     Physical and chemical properties
       atomic weight:                  :      28.08
       melting point                   :      1414oC
       boiling point                   :      3265oC
       vapour pressure                 :      at 1724oC: 0.133 kPa
       solubility in water             :      insoluble
       log Poctanol/water              :      0.53 (estimated)
       conversion factors              :      not applicable
       (20oC, 101.3 kPa)
      Data from Lew92, Lid96, http://esc.syrres.com.
      Silicon occurs as gray crystals, or as a brown amorphous solid (Lid96). Silicon
      is attacked by halogens and dilute alkali. Most acids, except hydrofluoric acid,
      do not attack it (Lid96). Dust explosions are possible; their strength is much
      higher than can be expected from the rate of pressure rise (Luc94, Win95).
      Silicon undergoes spontaneous oxidation in air to form a thin layer of silica on
      the surface (Sch93).
4     Uses
      Silicon is used in the synthesis of silanes and silicones; in the manufacture of
      transistors, silicon diodes, and similar semiconductors; it has been used in
      alloys, such as ferrosilicon and silicon copper, and as a reducing agent in
      high-temperature reactions. Organosilicon compounds have application as
      insecticides, rodenticides, herbicides, and pharmaceuticals, and the methyl and
      ethyl derivatives have industrial applications (ACG91).
           Hyperpure silicon can be doped with boron, gallium, phosphorus, or arsenic
      to produce silicon for use in transistors, solar cells, rectifiers, and other
      solid-state devices which are used extensively in the electronics and space-age
      industries. Hydrogenated amorphous silicon has shown promise in producing
      economical cells for converting solar energy into electricity (Lid96).
5     Biotransformation and kinetics
      The committee did not find data on the biotransformation and kimetics of
      silicon.
054-4 Health-based Recommended Occupational Exposure Limits
</pre>

====================================================================== Einde pagina 4 =================================================================

<br><br>====================================================================== Pagina 5 ======================================================================

<pre>6     Effects and mechanism of action
      Human data
      A large, multidisciplinary investigation of reproductive and other health
      outcomes has been performed in the semiconductor industry. In this industry,
      many chemicals are used, like arsenic and arsenic compounds, glycol ethers,
      xylene, mixed hydrocarbons, hydrofluoric acid, halogenated hydrocarbons, Cl2,
      BCl3, CCl4, SiCl4, CF4, SF6, and others (Ede90, Sch95b). In 1995, the results of
      the study have been published. In none of the studies, possible exposure to
      silicon was indicated (Sch95a). Therefore, the committee cannot use these data
      to evaluate the risk of occupational exposure to silicon.
           Human fetal lung cells showed dose-dependent cell necrosis and
      degeneration when incubated with a solution of 50-150 µg elemental silicon/mL
      (Yin82).
      Animal data
      A few investigations have been performed with elemental silicon, and several
      with welding dust, containing silicon.
           Intratracheal instillation of 50 mg ultrapurified silicon in rats caused
      primarily pneumoconiosis in the alveoli. The toxicity of silicon dust is
      considered to be lower than that of quartz dust. After 3 months, the lung tissue
      showed silicostic nodules, made up of macrophages containing black Si dust
      particles (Gol78).
           Intratracheal instillation of 25 mg elemental silicon induced slight
      pulmonary epithelial lesions after 12 months in rabbits (Sch71). In rats, 50 mg
      increased the relative lung weight after 12 months and introduced dust foci in
      the lungs, thickening of interalveolar septums, late and small development of
      fibrous connecting tissue in them, and bronchitis (Ark67).
           Inhalation of 50 mg elemental silicon increased the redox potential in the
      lungs of rats, which was at its maximum on day 6. There were no further data
      (Pra80). Inhalation of 1.55 mg/m3 in combination with radiant heat at 7.0
      cal/cm2 for 2 to 8 months increased the level of glycogen and decreased the
      level of lactate in the cornea of rats (Gmy75).
054-5 Silicon
</pre>

====================================================================== Einde pagina 5 =================================================================

<br><br>====================================================================== Pagina 6 ======================================================================

<pre>           Injections of 100-200 mg elemental silicon (particle size <10 µ) per animal
      over a long period did not induce toxicity in rats and guinea pigs. The authors
      noted that the cellular changes were typical of inert responses (McC37).
           The welding dusts, used in the animal experiments, contained various
      amounts of silicon (from 1.9 to 19.8%), and other elements, e.g., Fe, Mn, K, N,
      Ca, or F. In all studies, single doses of 50 mg of the dust were intratracheally
      administered to rats. Effects noted were: increased lipid peroxidation in lung
      and liver (Gel87, Gel89, Gel90), and modified albumins in blood serum
      (Bor88). After daily intratracheal instillation of 12.5 mg dust/kg bw for 1
      month, haemodynamic and metabolic changes, morphological changes in
      macrophages, atelectasis, and emphysema were noted in the cardiac-respiratory
      system of rats (Pok90).
      The committee did not find data from studies on carcinogenicity, genotoxicity,
      mutagenicity or reproduction toxicity of silicon.
7     Existing guidelines
      The current administrative occupational exposure limit (MAC) for silicon in the
      Netherlands is 10 mg/m3, 8-hour TWA.
           Existing occupational exposure limits for silicon in some European
      countries and in the USA are summarised in the annex.
8     Assessment of health hazard
      There is very little opportunity for occupational exposure to silicon in its
      elemental form. In metallurgy, silicon is heated in an oxygen atmosphere,
      resulting in oxidation to silicon dioxide (silica), before there is any potential for
      its volatilisation. Occupational exposure by inhalation and ingestion of mixed
      dusts containing silicon and silica may potentially occur during the manufacture
      of semiconductor-grade silicon and the manufacture of electronic equipment.
      However, these processes have to be carried out in very clean environments,
      and, as a result, exposures are minimised (Sch93).
           After intratracheal administration of elemental silicon to rats, lung effects
      were found like pneumoconiosis, epithelial lesions, bronchitis, and fibrosis
      (Ark67, Gol78, Sch71), but from these data no target organ can be derived.
054-6 Health-based Recommended Occupational Exposure Limits
</pre>

====================================================================== Einde pagina 6 =================================================================

<br><br>====================================================================== Pagina 7 ======================================================================

<pre>       The committee considers the toxicological database on silicon too poor to
       justify recommendation of a health-based occupational exposure limit.
       The committee concludes that there is insufficient information to comment on
       the level of the present MAC-value.
       References
ACG91  American Conference of Governmental Industrial Hygienists (ACGIH). Silicon. In: Documentation
       of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, Ohio, USA:
       ACGIH, 1991: 1287-8.
ACG02a American Conference of Governmental Industrial Hygienists (ACGIH). Guide to occupational
       exposure values -2002. Cincinnati OH, USA: ACGIH®, Inc, 2002: 116.
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®, Inc, 2002: 52.
Arb00a Arbejdstilsynet. Grænseværdier for stoffer og materialer. Copenhagen, Denmark: Arbejdstilsynet,
       2000; At-vejledning C.0.1.
Arb00b Arbetarskyddsstyrelsen. Hygieniska gränsvärden och åtgärder mot luftföroreningar. Solna, Sweden:
       Arbetarskyddsstyrelsen, 2000; Ordinance AFS 2000:3.
Ark67  Arkhangel’skaya LN. [Toxic effects of silicon and silicon nitride in rats.] Russian. Nov Dannye
       Toksikol Redk Metal Ikh Soedin 1967; 181-8. Chem Abstr 71:68978w.
Bor88  Borisenko SN, Voitkevich VG, Golovskaya GG, et al. [Determination of the content of modified
       forms of albumin for evaluation of the toxicity of welding dusts.] Russian. Dokl Akad Nauk Ukr
       SSR, Ser B 1988; 9: 64-6; cited from Chem Abstr 111: 2332u.
CEC00  Commission of the European Communities (CEC). Commission Directive 2000/39/EC of 8 June
       2000 establishing a first list of indicative occupational exposure limit values in implementation of
       Council Directive 98/24/EC on the protection of the health and safety of workers from the risks
       related to chemical agents at work. Official Journal of the European Communities 2000; L142
       (16/06/2000): 47-50.
DFG02  Deutsche Forschungsgemeinschaft (DFG): Senatskommission zur Prüfung gesundheitsschädlicher
       Arbeitsstoffe. MAK- und BAT-Werte-Liste 2002. Maximale Arbeitsplatzkonzentrationen und
       Biologische Arbeitsstofftoleranzwerte. Weinheim, FRG: Wiley-VCH, 2002; rep no 38.
Ede90  Edelman P. Environmental and workplace contamination in the semiconductor industry: implications
       for future health of the workforce and community. Environ Health Perspect 1990; 86: 291-5.
Gel87  Geleskul YF, Gorban LN, Baida NA, et al. [Peroxidation of lipids in animal tissues as an index of
       biological agressiveness of welding aerosols.] Russian. Vrach Delo 1987; 6: 108-10; cited from
       Chem Abstr 107: 192519y.
054-7  Silicon
</pre>

====================================================================== Einde pagina 7 =================================================================

<br><br>====================================================================== Pagina 8 ======================================================================

<pre>Gel89  Geleskul YF, Volkova NN, Voitkevich VG, et al. [Effect of metals of silicon-containing welding
       dust on the activity of a glutathione antioxidant system in the rat liver.] Russian. Dokl Akad Nauk
       Ukr SSR, Ser B 1989; 9: 58-60; cited from Chem Abstr 112: 2292b.
Gel90  Geleskul YF, Kornuta NA, Voitkevich VG, et al. [Effect of metals of silicon-containing welding
       dust on the state of peroxidation of lipids in white rat tissues.] Russian. Dokl Akad Nauk Ukr SSR,
       Ser B 1990; 7: 74-7; cited from Chem Abstr 113: 186279c.
Gmy75  Gmyrya AI, Antonova AI. [Carbohydrate metabolic indexes in eye tissues after exposure to
       silicon-containing dust and radiant heat.] Russian. Oftal’mol Zh 1975; 30: 26-8; cited from Chem
       Abstr 83: 91791m.
Gol78  Golodnikov YN. [Experimental silicosis induced by the ultrapure crystalline silicon dust and the
       effects of poly(vinylpyridine-N-oxide) on its evolution.] Russian. Gig Tr Prof Zabol 1978; 12: 31-6;
       cited from Chem Abstr 90: 81691j.
HSE02  Health and Safety Executive (HSE). EH40/2002. Occupational exposure limits 2002. Sudbury
       (Suffolk), England: HSE Books, 2002: 25.
Lew92  Lewis RJ Sr, ed. In: Sax’s dangerous properties of industrial materials. 8th ed. New York, USA: Van
       Nostrand Reinhold, 1992: 3042.
Lid96  Lide DR, Frederikse HPR, ed. CRC Handbook of chemistry and physics. 77th ed. Boca Raton FL,
       USA: CRC Press, 1996; 4-27, 82.
Luc94  Lucas J. Explosionsfähige Staub/Luft-Gemische. Bewertung von Explosionskenngrößen, die in
       verschiedenen Apparaturen ermittelt wurden. TU 1994; 35: 61-8.
McC37  McCord CP, Frederick WG, Stolz S. The toxicity of silicon. J Lab Clin Med 1937; 23: 278-9; cited
       from Chem Abstr 32: 5074d.
Pok90  Pokrovskaya TN, Cherednichenko, VM. [Effect of welding dusts on morphology of
       bronchopulmonary system and heart in experiment.] Russian. Gig Tr Prof Zabol 1990; 9: 37-40;
       cited from Chem Abstr 114: 1907k.
Pra80  Prager P, Puppi A, Zsoldos T, et al. [Changes of redox potentials in the lungs in connection with the
       inhalation of silicon powder.] Hungarian. Kiserl Orvostud 1980; 32: 378-80; cited from Chem Abstr
       93: 231973f.
Sch71  Schepers GWH. Lung tumors of primates and rodents. Ind Med Surg 1971; 40: 48-53.
Sch93  Schultz CO. Silicon and silicates, including asbestos. In: Clayton GD and Clayton FE, ed.
       Toxicology. 4th ed. New York, USA: John Wiley and Sons, Inc, 1993: 831-90 (Patty’s industrial
       hygiene and toxicology; Vol II, Pt A).
Sch95a Schenker MB, Gold EB, Beaumont JJ, et al. Association of spontaneous abortion and other
       reproductive effects with work in the semiconductor industry. Am J Ind Med 1995; 28: 639-59.
Sch95b Schmidt R, Scheufler H, Bauer S, et al. Toxicological investigations in the semiconductor industry:
       III: Studies on prenatal toxicity caused by waste products from aluminum plasma etching processes.
       Toxicol Ind Health 1995; 11: 49-61.
054-8  Health-based Recommended Occupational Exposure Limits
</pre>

====================================================================== Einde pagina 8 =================================================================

<br><br>====================================================================== Pagina 9 ======================================================================

<pre>SZW02 Ministerie van Sociale Zaken en Werkgelegenheid (SZW). Nationale MAC-lijst 2002. The Hague,
      the Netherlands: Sdu, Servicecentrum Uitgevers, 2002: 39.
TRG00 TRGS 900. Grenzwerte in der Luft am Arbeitsplatz; Technische Regeln für Gefahrstoffe. BArbBl
      2000; 2.
Win95 Van Wingerden K, Pedersen GH, Eckhoff RK. Violence of dust explosions in integrated systems.
      Process Safety Progr 1995; 14: 131-8.
Yin82 Yin L. [Effect of silicon dust on the ultrastructure and function of pulmonary cells.] Chinese.
      Shengwu Huaxue Yu Shengwu Wuli Jinzhan 1982; 43: 44-7; cited from Chem Abstr 97: 34357q.
054-9 Silicon
</pre>

====================================================================== Einde pagina 9 =================================================================

<br><br>====================================================================== Pagina 10 ======================================================================

<pre>             Annex
Occupational exposure limits for silicon in various countries.
country                            occupational exposure            time-weighted       type of exposure notea  referenceb
-organisation                      limit                            average             limit
                                   ppm            mg/m3
the Netherlands
- Ministry of Social Affairs       -              10                8h                  administrative          SZW02
and Employment
Germany
- AGS                              -              -                                                             TRG00
- DFG MAK-Kommission               -              -                                                             DFG02
Great Britain
- HSE                              -              10c, 4d           8h                  OES                     HSE02
Sweden                             -              -                                                             Arb00b
Denmark                            -               10               8h                                          Arb00a
USA
- ACGIH                            -              10                8h                  TLV                     ACG02b
- OSHA                             -              15c, 5d           8h                  PEL                     ACG02a
- NIOSH                            -              10c, 5d           10 h                REL                     ACG02a
European Union
- SCOEL                            -              -                                                             CEC00
a
     S = skin notation; which means that skin absorption may contribute considerably to the body burden; sens = substance
     can cause sensitisation.
b
     Reference to the most recent official publication of occupational exposure limits.
c
     Total inhalable dust.
d
     Respirable fraction.
054-10       Health-based Recommended Occupational Exposure Limits
</pre>

====================================================================== Einde pagina 10 =================================================================

<br><br>