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Platinum and Platinum Compounds Platinum and platinum compounds Health-based recommended occupational exposure limit Gezondheidsraad Voorzitter Health Council of the Netherlands Aan de minister van Sociale Zaken en Werkgelegenheid Onderwerp : Aanbieding advies Platinum and platinum compounds Uw kenmerk : DGV/MBO/U-932542 Ons kenmerk : U-5204/HS/pg/459-R56 Bijlagen : 1 Datum : 12 juni 2008 Geachte minister, Graag bied ik u hierbij het advies aan over de beroepsmatige blootstelling aan platina en platinaverbindingen. Het maakt deel uit van een uitgebreide reeks, waarin gezondheids- kundige advieswaarden worden afgeleid voor concentraties van stoffen op de werkplek. Dit advies over platina en platinaverbindingen is opgesteld door de Commissie Gezondheid en Beroepsmatige Blootstelling aan Stoffen (GBBS) van de Gezondheidsraad en beoordeeld door de Beraadsgroep Gezondheid en Omgeving. Ik heb dit advies vandaag ter kennisname toegezonden aan de minister van Volksgezondheid, Welzijn en Sport en aan de minister van Ruimte en Milieu. Hoogachtend, prof. dr. J.A. Knottnerus Bezoekadres Postadres Parnassusplein 5 Postbus 16052 2511 VX Den Haag 2500 BB Den Haag Telefoon (070) 340 70 04 Telefax (070) 340 75 23 E-mail: [email protected] www.gr.nl Platium and platinum compounds Health-based recommended occupational exposure limit to: the Minister of Health, Welfare and Sport No. 2008/12OSH, The Hague, June 12, 2008 The Health Council of the Netherlands, established in 1902, is an independent scientific advisory body. Its remit is “to advise the government and Parliament on the current level of knowledge with respect to public health issues...” (Section 22, Health Act). The Health Council receives most requests for advice from the Ministers of Health, Welfare & Sport, Housing, Spatial Planning & the Environment, Social Affairs & Employment, and Agriculture, Nature & Food Quality. The Council can publish advisory reports on its own initiative. It usually does this in order to ask attention for developments or trends that are thought to be relevant to gov- ernment policy. Most Health Council reports are prepared by multidisciplinary committees of Dutch or, sometimes, foreign experts, appointed in a personal capacity. The reports are available to the public. The Health Council of the Netherlands is a member of the European Science Advisory Network for Health (EuSANH), a network of science advisory bodies in Europe. The Health Council of the Netherlands is a member of the International Network of Agencies for Health Technology Assessment (INAHTA), an international collaboration of organisations engaged with health technology assessment. INAHTA This report can be downloaded from www.healthcouncil.nl. Preferred citation: Health Council of the Netherlands. Platinum and platinum compounds. Health- based recommended occupational exposure limit. The Hague: Health Council of the Netherlands, 2008; publication no. 2008/12OSH. all rights reserved ISBN: 978-90-5549-718-8 Contents Samenvatting en advieswaarde 11 Executive summary 19 Part I Health Council of the Netherlands: Platinum and platinum compounds 25 1 Scope 27 1.1 Background 27 1.2 Committee and procedure 27 1.3 Data 28 2 Identity, properties and monitoring 31 2.1 Chemical identity 31 2.2 Physical and chemical properties 31 2.3 EU classification and labelling 33 2.4 Analytical methods 33 3 Sources and use 37 Contents 7 4 Exposure 39 4.1 Ambient exposure 39 4.2 Occupational exposure 40 5 Kinetics 43 5.1 Absorption 43 5.2 Distribution 46 5.3 Elimination 47 5.4 Biomonitoring 49 5.5 Summary 51 6 Mechanism of action 53 6.1 Human studies 53 6.2 Animal studies 54 7 Effects 57 7.1 Observations in humans 57 7.2 Animal experiments 64 7.3 Summary and evaluation 79 8 Existing guidelines, standards and evaluations 83 8.1 General population 83 8.2 Working population 83 8.3 Evaluations 84 9 Hazard assessment 87 9.1 Assessment of health hazard 87 9.2 Recommendation of a health-based exposure limit 89 9.3 Groups at extra risk 90 9.4 Health-based recommended occupational exposure limit 91 9.5 Additional consideration 91 10 Recommendations for research 93 References 95 8 Platinum and platinum compounds Annexes 101 A Request for advice 103 B The committee 105 C Comments on the public review draft 109 D Characteristics of the cohort studied by Merget et al. 111 Part II Arbete och Hälsa: Platinum 113 Contents 9 10 Platinum and platinum compounds Samenvatting en advieswaarde Vraagstelling Op verzoek van de Minister van Sociale Zaken en Werkgelegenheid leidt de Commissie Gezondheid en Beroepsmatige Blootstelling aan Stoffen (GBBS, voorheen WGD) van de Gezondheidsraad gezondheidskundige advieswaarden af voor stoffen in lucht op de werkplek waaraan mensen beroepsmatig kunnen worden blootgesteld. In dit advies worden het metaal platina en een aantal plati- naverbindingen onder de loep genomen. Het advies is opgesteld in samenwerking met de Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals (NEG), een adviescom- missie van de Noord-Europese regeringen. Het gezamenlijke rapport over de gevolgen van beroepsmatige blootstelling aan platina en platinaverbindingen, gepubliceerd in Zweden in 1997 (Arbete och Hälsa 1997: 14), is in zijn geheel opgenomen in deel 2 van dit advies. Deel 1 bestaat uit een kort overzicht van de onderzoeken die in deel 2 aan de orde komen, een bespreking van de onderzoeks- gegevens die sinds 1997 beschikbaar zijn gekomen, en de gezondheidskundige evaluatie van platina en zijn verbindingen. De conclusies in het advies zijn gebaseerd op wetenschappelijke publicaties die vóór september 2007 zijn verschenen. Ze komen geheel voor rekening van de commissie GBBS van de Gezondheidsraad. Samenvatting en advieswaarde 11 Fysische en chemische eigenschappen en gebruik In het rapport worden platina (CAS nummer 7440-06-4) en een aantal platina- verbindingen behandeld. Op platina gebaseerde geneesmiddelen tegen kanker (zoals bij voorbeeld cisplatina) worden niet besproken. Platina is een zilvergrijs edelmetaal. Het wordt verkregen door winning uit ertsen of door recycling van platinahoudende metalen, en gezuiverd door omzet- ting in hexachloroplatinazuur. Platina is van grote commerciële waarde, omdat het in hoge mate bestand is tegen corrosie. Ook is het waardevol als katalysator voor oxidatie- en reductieprocessen. Platina en zijn verbindingen worden hoofdzakelijk gebruikt in de automo- bielindustrie (als katalysator in de uitlaat van auto's). Daarnaast wordt het toege- past in sieraden en elektronica en in de (petro)chemische industrie en, in nog geringere mate, in de tandheelkunde (voor bruggen, kronen, en dergelijke). Ook wordt platina gebruikt in de farmaceutische industrie (in geneesmiddelen tegen bepaalde vormen van kanker). Monitoring Blootstelling aan platina en platinaverbindingen vindt voornamelijk plaats door inademing van stofdeeltjes. Om concentraties van platina en platinaverbindingen op de arbeidsplek te kunnen meten, zijn methoden ontwikkeld om de concen- traties in de lucht te kunnen bepalen. Verschillende organisaties, zoals het Engelse Health and Safety Executive (HSE) en het Amerikaanse National Institute for Occupational Safety and Health (NIOSH) en de Occupational Safety and Health Administration (OSHA), hebben manieren beschreven om dat te doen. De lucht wordt dan aangezogen via filters, waarna de filters worden behan- deld met een zure oplossing. Met behulp van speciale spectrometrische tech- nieken wordt vervolgens de hoeveelheid platina bepaald. In het algemeen zijn langdurige monsternemingen nodig. De bepalingsmethoden kunnen geen onder- scheid maken tussen metallisch platina en platinaverbindingen. NIOSH heeft ook methoden beschreven voor de bepaling van platina in bio- logische monsters (bloed, weefsel, urine). 12 Platinum and platinum compounds Huidige grenswaarden In Nederland geldt een wettelijke grenswaarde voor beroepsmatige blootstelling aan deeltjes metallisch platina van 1 mg platina per m3 lucht. Deze waarde is in overeenstemming met Europese richtlijnen. Nederland heeft geen waarde(n) voor platinaverbindingen. Een aantal Europese landen (Denemarken, Engeland, Finland, Noorwegen, Zweden) en Amerikaanse organisaties (ACGIH, NIOSH, OSHA) hanteren grenswaarden voor platinazouten die oplosbaar zijn in water van 2 µg platina per m3 lucht. Kinetiek Platinadeeltjes en platinazouten die het lichaam binnenkomen via de ademhal- ingsorganen en de mond worden niet gemakkelijk opgenomen, tenminste als ze niet in water oplosbaar zijn. De absorptie is in dat geval waarschijnlijk minder dan 1%. Platinazouten die wel oplossen in water worden echter beter geabsor- beerd. Platina dat in het lichaam wordt opgenomen wordt verdeeld over de ‘zachte’ weefsels, met name de nieren, maar wordt soms ook teruggevonden in het bot- stelsel. De uitscheiding vindt voornamelijk met de urine plaats en lijkt zich in twee fasen te voltrekken. Bij mensen zijn twee biologische halfwaardetijden vastgesteld van respectievelijk ongeveer 50 uur en ongeveer 24 dagen. In de literatuur zijn geen gegevens te vinden over de omzetting in het lichaam van platina of platinaverbindingen. Effecten op mensen Platina en platinaverbindingen die niet oplosbaar zijn in water Er zijn geen gegevens beschikbaar uit onderzoek naar de mogelijke effecten bij mensen door blootstelling aan metallisch platina en niet-oplosbare platina- verbindingen. In water oplosbare platinaverbindingen Over de effecten van oplosbare platinaverbindingen zijn wel gegevens beschik- baar. Daaruit blijkt dat contact met deze verbindingen vooral leidt tot overgevoe-
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