AEH Zentrum für Arbeitsmedizin, Ergonomie und Hygiene AG Nanotechnology: Risks, protection measures and current recommendations

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1 AEH Zentrum für Arbeitsmedizin, Ergonomie und Hygiene AG Nanotechnology: Risks, protection measures and current recommendations Elisabeth M. Berger Occupational physician, AEH Zürich

2 Information about: Principles and applications Hazard potential: current situation image source: EMPA technical, organizational and personal safety precautions current recommendations, guidelines, legal requirements nanotechnology: risks and protection 2

3 In Switzerland (nanoinventar 2008) about 600 companies use nanoparticles about persons at workplaces with nanoparticles (0.6% of all productive companies in CH and 0.08% of all employees in productive companies in CH) - may be in contact with nanoparticles nanopartikel applications mainly in chemical industry automotive suppliers electrical industry trading companies surface treatment glass and ceramic and stone treatment nanotechnology: risks and protection 3

4 Definition Nanomaterial A natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50 % or more of the particles in the number size distribution, one or more external dimensions is in the size range 1 nm nm. In specific cases and where warranted by concerns for the environment, health, safety or competitiveness the number size distribution threshold of 50 % may be replaced by a threshold between 1 and 50 %. By derogation from the above, fullerenes, graphene flakes and single wall carbon nanotubes with one or more external dimensions below 1 nm should be considered as nanomaterials. EU Commission 2011/696/EU nanotechnology: risks and protection 4

5 Differences betweeen nanomaterials in Size Geometry Chemical composition Physikochemical qualities of the surface Ability to create reactive oxygen species (ROS) Solubility in biological media nanotechnology: risks and protection 5

6 Classifikation nanomaterial nanopartikel nanofiber nanoplate (3 dimensions nanoscale) (2 dimensions nanoscale ) (1 dimension nanoscale) nanowire nanotube nanobar Carbon-Nanoröhrchen (Carbon-Nanotubes) : (Nanomaterial with one or more external dimensions below 1 nm ) Single walled (SWCNT) - Multi walled (MWCNT) nanotechnology: risks and protection 6

7 WHO-Fiber respirable... + fibrous (length-to-diameter ratio > 3/1) + thin (< 3 μm) + long (> 5 μm μm) + bioresistant nanotechnology: risks and protection 7

8 Routes of exposure Incorporation by: inhalation: gas, vapours, dusts, aerosols swallow: dusts liquids absorption by the skin: dusts liquids nanotechnology: risks and protection 8

9 Separation efficiency Respirable dust non respirable fraction tracheo-bronchial fraction nose-throat-larynx respirable fraction alveolar fraction thoracic fraction Red = Nanofraction aerodynamic diameter nanotechnology: risks and protection 9

10 Inhalation - respirable dust trachea pulmonary alveole bronchial tubes Potential effects of dust pollution: inflammation fibrosis (amount of connective tissue ) tumor image source : H.F.Krug, P.Wick, Angew. Chem. 2011, 123, nanotechnology: risks and protection 10

11 Biological effects of nanoparticles Effects caused by the particle morphology : GBD = alveolar, granular, bioresistant dust WHO-Fibers (long, thin, bioresistant) route of exposure: inhalation > inflammation > carcinogenicity Effects caused by the chemical characteristics : Specific toxicity routes of exposure: inhalation, skin There was no new effect found caused only by nanomaterials! nanotechnology: risks and protection 11

12 3 Groups 1. Nanomaterials releasing alveolar granular bioresistant dusts (GBD) without specific toxicity 1. Fibrous nanomaterials releasing alveolar bioresistant (rigid) flue (WHO-fiber) 2. Nanomaterials with a specific chemical toxicity requiring a case-to-case assessment nanotechnology: risks and protection 12

13 1. Nanomaterials releasing alveolar granular bioresistant dusts (GBD) without specific toxicity Principle granular TiO 2 respirable (alveolar dust) bioresistant(not-/hardly soluble) without any known specific toxicity Effect endpoint inflammation (lungtissue) lung cancer Applies to alveolar dust consisting of /sourcing from materials in powder form work processes picture BAuA / Nanolabor nanotechnology: risks and protection 13

14 2. Fibrous nanomaterials releasing alveolar bioresistant (rigid) flue (WHO-fiber) Principle - fibrous (length/diameter > 3/1) - thin (< 3 μm) - long (> 5 μm μm) - bioresistant Effect endpoint - inflammation (lungtissue) - cancer (lung, mesothelioma,... ) Applies to: - asbest (and other fiber minerals) - synthetic mineral fibres - fibrous nanomaterials - innovative fiber materials picture BAuA / Nanolabor nanotechnology: risks and protection 14

15 3. Nanomaterials with a specific chemical toxicity requiring a caseto-case assessment hardly soluble materials >release of toxic ions (Cd) >catalytic activity (Ag, Ni) >chemically reactive functional groups readily soluble materials...loosing their nano-properties quickly when incorporated... and therefore the riks are correspondending to the bulkmaterials (nano-silicic-acid) nanotechnology: risks and protection 15

16 Applying in general Special precautions shall be taken in case of carcinogenic material such as: arsenic or arsenic compounds (like in quantum dots) cadmium or cadmium compounds (like in quantum dots) nickel or nickelcompunds (like nickelsulfid or nickeloxide) crystalline silica (quartz) nanotechnology: risks and protection 16

17 riskassessment and riskmanagement exposure (load) + effect of the material ( hazard ) riskassessment riskevaluation riskmanagement nanotechnology: risks and protection 17

18 Exposure What I m doing With what How How often and with How much nanotechnology: risks and protection 18

19 effect (hazard) : Material Safety Data Sheets (MSDS) e.g. msds nano-titandioxid (pdf) Link: Fproduct%2Fsial%2F14021%3Flang%3Dde General limit for dust TiO 2 PPE: safety glasses, nitrile-gloves, FFP1-mask nanotechnology: risks and protection 19

20 Study about TiO 2 Toxic effects of various modifications of a nanoparticle following inhalation ( BAuA 2013) Comparison (Wistar-rats): TiO 2 UV TITAN M262 TiO 2 UV TITAN M212 TiO 2 P25 difference in crystal structure and surface modification 3, 12 and 47 mg/m 3, 6h / 5 days / week 28 days > residuals in lung, tissue recovery different nanotechnology: risks and protection 20

21 Precautionary matrix for synthetic nanomaterials CH nanotechnology: risks and protection 21

22 Precautionary matrix nanotechnology: risks and protection 22

23 evaluation nanotechnology: risks and protection 23

24 limits Only recommendations No healthbased occupational limit values Dose response relationship not clear enough Editor Nanomaterial recommended exposure limit (REL) National Institute of Occupational Safety and Health NIOSH, USA) National Institute of Occupational Safety and Health NIOSH, USA) Suva Titandioxid (< 100nm) Carbon nano tubes (CNT) and -fibers (CNF) Carbon nano tubes (CNT) and fibers (CNF) 0.3 mg/m 3 10h/day and 40h/week mg/m 3 1 μg/m 3 elemental carbon 0.01 fibers/ml Suva Common dust 3 mg/m 3 (Suva Titandioxid like common dust (not nano-specific) IFA (Germany) IFA (Germany) Biopersistent granular Nanomaterials Density > kg/m 3 Density < kg/m 3 Carbon nano tubes (CNT) WHO-fibre properties cannot be ruled out particles/cm 3 (measuring range nm) particles/cm fibers/m nanotechnology: risks and protection 24

25 limits CH MAK-Value (maximum workplace exposure limit) of 3 mg/m 3 for alveolar dust and 10 mg/m 3 for respirable dust applies to common dust limit. Because of the current research less clear dose-effect-relations for nano-materials Carbon-nano-tubes and fibers length > 5 μm, diameter < 3 μm, length-to-diameter > 3:1 >> 0.01 fiber/ml. This value is corresponding to the limit value of respirable asbest fibers nanotechnology: risks and protection 25

26 Arbeitsgesetz (labour law) and UVG Arbeitsgesetz, Art. 6 Pflichten der Arbeitgeber und Arbeitnehmer 1 Der Arbeitgeber ist verpflichtet, zum Schutze der Gesundheit der Arbeitnehmer alle Massnahmen zu treffen, die nach der Erfahrung notwendig, nach dem Stand der Technik anwendbar und den Verhältnissen des Betriebes angemessen sind. Er hat im Weiteren die erforderlichen Massnahmen zum Schutze der persönlichen Integrität der Arbeitnehmer vorzusehen. 2 2 Der Arbeitgeber hat insbesondere die betrieblichen Einrichtungen und den Arbeitsablauf so zu gestalten, dass Gesundheitsgefährdungen und Überbeanspruchungen der Arbeitnehmer nach Möglichkeit vermieden werden. - Occupational diseases > UVG > comissioning of the Suva: Occupational Medical Precautions and working out limits ( Grenzwerte am Arbeitsplatz ) > Up to now no nano-specific rules > Common rules for hazardous material and safety in laborateries apply nanotechnology: risks and protection 26

27 Measures S T O P! (Substitution) Technical modification: closed systems, encapsulation Organisation: shorten time of contact Personal measures: PPE (Personal protection equipment) Occupational Medical Precautions nanotechnology: risks and protection 27

28 Personal protection equipment Disposable-respirators with suitable filters (FFP3) + Disposable-gloves (ggf. bei Einweghandschuhen 2 Lagen übereinander) + Closed safety glasses + protective clothing ( CNTs) Polyethylen high density HDPE (Nanosafe 2008) but: always note other hazards like chemicals > other protection measures needed! nanotechnology: risks and protection 28

29 Occupational Medical Precautions analysis of the current situation: - Medical history, especially lung-or bronchial diseases - Physical examination - Current pulmonary function testing (spirometry) Further examinations (Rx) Biomonitoring (blood, urine, et alt.) does not make sense at this time Monitoring of progress adverse health effects? >epidemiology - offer of occupational medical precautions by SGU nanotechnology: risks and protection 29

30 outlook Nanomaterial: Hazard properties of the bulk material release of bioresistant products can cause additional health risks hazards other innovative materials with structures > 100 nm may causes similar health risks unfavorable dusting tendency some nanomaterials (esp. fibrous) some rigid CNTs, which release fibre dust (WHO-fibre) in a significant amount, might have a comparable hazard to employees as asbest > CH: swiss plan of action synthetic nanomaterials, Nanoinventar > Seco: SDB: Guidelines for synthetic nanomaterials > USA: NIOSH Nanotechnology field team > Work in progress: Guideline for action (EU, NANOVALID) nanotechnology: risks and protection 30

31 uncertainty of valuation Rate of knowledge risk 2015 CNT II ( flexible fibres, dusty) Modified from: R. Packroff, Nanotechnologie, Wuppertal, 2014 growth rate of knowledge nanotechnology: risks and protection 31

32 Nanosicherheitsforschung sind wir auf dem richtigen Weg? Nano security research are we in the right track? Harald F. Krug Angewandte Chemie Volume 126, Issue 46, pages , 10 OCT 2014 DOI: /ange nanotechnology: risks and protection

33 contact Elisabeth M. Berger AEH Zentrum für Arbeitsmedizin, Ergonomie und Hygiene AG Militärstrasse Zürich Telefon: nanotechnology: risks and protection 33