The study is a follow-up of investigations done in the years 1999-2002 in bakery employees. The main purposes are to look at the associations between flour dust exposure and respiratory disease, and to find out the best ways to reduce the flour dust levels in the working environment.

Background and Methods:

Supported by the The Confederation of Norwegian Enterprise (CNBI) Working Environment Fund a follow-up study of 184 bakery workers in 5 bakeries was done in 2012, appr. 10 years after a similar study in 1999-2002. In addition a cross-sectional study in 2 other bakeries (one 'bread-factory', and a traditional bakery with three small bake shops) was added.

Altogether 253 participants, among them 61 former bakery workers, were investigated with use of questionnaires, allergy-testing (skin prick testing, and blood samples for specific IgE and total IgE), spirometry with reversibility testing, exhaled NO-measurement, and nasal measurements.

As in 1999-2002 an extensive exposure assessment was performed including personal samples of total dust (Gelman), inhalable dust (PAS6), as well as direct reading measurements of dust (Dust Track). A Job Exposure Matrix (JEM) was created enabling each participant to be assigned an exposure value of probable mean daily flour-dust exposure based on work-tasks and bakery.

Aim of study:

• Follow-up of the participants in the 1999-2002 study, both still active bakery workers and former workers, on health-status focusing on respiratory disease, sensitization to common and occupational allergens, level of sick-leave and reasons for quitting as a baker.
• Inclusion of 'new' bakery workers into the cohort as a cross-sectional study, and to compare health-status in two cross-sectional cohorts.
• To assess personal exposure to flour-dust among workers in 7 bakeries, as part of the cross-sectional study described above.
• To identify implemented flour-dust exposure reduction measures in bakeries participating in 1999-2002, and to assess the potential impact of these measures on the exposure to flour dust.

Inclusion Criteria:

• Employed in a bakery for more than 6 months
• and/or participant of the investigations done in 1999-2002 in 6 bakeries

1. All the employees in 5 bakeries investigated in 1999-2002 (one of the original 6 bakeries has fused with one of the others)
2. All the employees in additional 2 bakeries located in the same Hordaland county, Norway, as the other 5 bakeries