Public Defence: Hilde Pettersen Notø

MSc Hilde Pettersen Notø at Institute of Health and Society will be defending the thesis “Dust Exposure among European Cement Production Workers. Determinants of Thoracic Aerosol Exposure and Relationships between Different Aerosol Fractions.” for the degree of PhD (Philosophiae Doctor).

Trial Lecture – time and place

See Trial Lecture.

Adjudication committee

  • First opponent: Docent Håkan Tinnerberg, Sahlgrenska Universitetssjukhuset
  • Second opponent: Docent Göran Lidén, Institutionen för miljövetenskap och analytisk kemi
  • Third member and chair of the evaluation committee: Associate Professor May Brit Samersaw-Lund, University of Oslo

Chair of the Defence

Professor Gunnar Tellnes, University of Oslo

Principal Supervisor

Research porfessor Emeritus Wijnand Eduard, Statens arbeidsmiljøinstitutt

Summary

Contradictory results of respiratory health effects related to dust exposure have been reported among workers in cement plants. The former studies had mainly cross-sectional designs and had limited data on exposure levels. In addition, upcoming new European regulations through REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) and CLP (Classification, Labelling and Packing) that could have consequences for the cement industry and possibly occupational exposure limits (OELs).

Our aims were with a longitudinal design to describe and quantify the thoracic aerosol exposure for different job types and selected exposure determinants among European cement production workers, and find relationships between respirable, thoracic, ”total” dust, and inhalable aerosol fractions.

The sampling of the thoracic particle size fraction (particles able to penetrate beyond the larynx) was chosen in order to reflect the exposure of the bronchial tree of the lungs. The sampling strategy was based on personal full-shift measurements performed on randomly selected workers within seven job types in the production departments at 22 cement plants situated in 8 European countries (including Turkey). The sampling campaigns were conducted in 2007, 2009, and 2011. All dust samples were analyzed gravimetrically and with linear and mixed regression statistical models.

In total 6111 measurements were collected and the exposure varied between plants and job types, with production, cleaning, and maintenance as the most exposed. Six of the 22 plants had no arithmetic mean (AM) levels above the lowest observed adverse effect level (LOAEL) (estimated by Nordby et al .2016) while all the other exceeded by one or several AM. The exposure level in many plants may cause reduction in lung function, but some plants (28%) seem able to produce cement without the risk of adverse respiratory effects.
The relationships between thoracic dust and respirable, total dust, and inhalable dust aerosol fractions were dependent on exposure level with median ratios of 0.51, 2.4 and 5.9, respectively.
 

Additional information

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Published June 4, 2019 10:12 AM - Last modified June 4, 2019 11:49 AM