About the Authors

Andreas Tornevi

andreas.tornevi@umu.se

Affiliation Occupational and Environmental Medicine, Department of Public Health and Clinical Medicine, Umeå University, Sweden

Olof Bergstedt

Affiliation Department of Civil and Environmental Engineering, Water Environment Technology, Chalmers University of Technology, Gothenburg, Sweden

Bertil Forsberg

Affiliation Occupational and Environmental Medicine, Department of Public Health and Clinical Medicine, Umeå University, Sweden

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: AT OB BF. Analyzed the data: AT. Wrote the paper: AT. Choose statistical methods: AT. Evaluated results: AT OB BF. Contributed with data material: OB. Approved the final manuscript: AT OB BF.