Epidemiologiska data vid identifiering och värdering av cancerrisker i arbetsmiljön. Dieselavgaser

Transkript

1 Epidemiologiska data vid identifiering och värdering av cancerrisker i arbetsmiljön Dieselavgaser Per Gustavsson Institute of Environmental Medicine

2 Partiklar från förbränningsmotor 2

3 Hälsoeffekter hos människa från dieselavgasexponering i arbetsmiljön Luftvägssjukdom -irritation/inflammation Lungcancer Hjärt-kärlsjukdom hjärtinfarkt?

4 Exponeringsindikatorer Dieselavgaser komplex blandning inget totalmått existerar Vad ska vi mäta? Sammansättningen av olika gaser och partikelfraktioner är olika i olika situationer (bränsle, motorer, driftsförhållanden) Kvävedioxid - NO2 Elementärt kol - EC

5 Studerade yrkesgrupper Gruvarbetare, tunnelarbetare Järnvägsarbetare Maskinförare operatörer Garagearbetare Stuveriarbetare Fordonsförare (buss, taxi, lastbil)

6 Lewné, Ann Occup Hyg 2007

7 IARC hazard identification International Agency for Research on Cancer (WHO) elevated the classification of DME in 2012 to Group 1 Group 1 Carcinogenic to humans Sufficient evidence in humans Sufficient evidence in experimental animals (Stong mechanistic data)

8 IARC s most influential studies Tree large studies with well characterized exposure Railroad workers pos association, dose-response, smoking data in accompanying CC study showed similar risks Trucking industry workers pos association, dose-response trend, indirect smoking adj. Critical issue adjustment for employment duration Non-metal miners pos association, dose-response, smoking adj Three smaller cohort studies also specifically relating the findings to assessments of diesel exhaust Swedish bus garage workers supportive, no smoking data German potash miners smoking adj, indicative dose-response Critical issue adjustment for duration of employment Swedish dock workers pos association, indicative of trend, smoking adj. Asbestos? A number of additional cohort studies with less precise definition of exposure generally were supportive but were considered less informative for the evaluation.

9 5 µg EC/m 3 10 µg EC/m 3 Vermeulen et al EHP 2014

10 LUCAS study The average number of mg-years/m3 of nitrogen dioxide in the highest cumulative dose group (table 4), for which a lung cancer excess was found, was The average exposure duration in this group was 34.6 years, giving an average exposure level of 160 μg/m3 Gustavsson et al Am J Epid 2000

11 Vermeulen 2014, NEG years of occupational exposure to diesel exhaust at 1, 10 and 25 µg EC/m 3 was estimated to result in 17, 200 and 689 extra lung cancer deaths per , respectively, by the age of 80 years.

12 Svenskt gränsvärde Gränsvärdet baserat på kvävedioxid: 2000 µg NO 2 /m3 (AFS 2015:6, Lundberg et al AoH 1986) Detta motsvarar grovt 2 000/6 = 333 µg EC (Lewné 2007) 20µg EC/m 3 föreslogs i USA 2003 (NIOSH) Effekter på luftvägar och ökad lungcancerrisk finns vid nivåer under dagens gränsvärde

13 Både EUs SCOEL och AV diskuterar revidering av nuvarande gränsvärdet. SCOEL 0.5 ppm NO2 = µg/m3 5 eller 10 µg EC/m3

14 NEG s view Critical effects are pulmonary inflammation and lung cancer. For older technology diesel engines, these effects are mainly associated with the particulate fraction of the exhaust, making DEP a good candidate for an exposure indicator. As it is challenging to distinguish between DEP and other respirable dust at a workplace, respirable EC may be applied as a marker for DEP. For new technology diesel engine exhaust with significantly reduced DEP and EC mass concentrations, EC may not be an equally useful exposure indicator. NO2 is likely to be a more relevant exposure indicator for new technology diesel engine exhaust, it may be appropriate to set an occupational exposure limit value for diesel exhaust both as respirable EC and as NO2. Both of these values should be fulfilled at a workplace where diesel engines are applied. Based on a meta-analysis of three epidemiological studies by a log-linear metaregression model, 45 years of occupational exposure to diesel exhaust at 1, 10 and 25 µg EC/m3 was estimated to result in 17, 200 and 689 extra lung cancer deaths per , respectively, by the age of 80 years.