**5. Conclusions**

Substantial proportions of study subjects who had lived near asbestos factories, shipbuilding facilities, and slate roof-dense areas were exposed to asbestos through occupational, household, and slate roof routes. After controlling for sex, age, smoking status, and other asbestos exposure routes, we found that the occupational, household, neighborhood, and slate roof exposure routes were associated with LLF and PD; PD; LLF, PD, and LM; and LLF, PD, and LM, respectively. To our knowledge, this may be the first report of the health effects of slate roof exposure. However, this study is vulnerable to misclassifications of exposure and outcome measurements, information bias, and other potential confounders, including SES. A well-designed study is needed to overcome those limitations.

**Author Contributions:** Conceptualization, D.K.; Methodology, Y.-K.K.; Software, S.-Y.K.; Validation, Y.-K.K. and S.-Y.K.; Formal Analysis, Y.-Y.K., M.S., M.-S.L., and H.-J.B.; Writing-Original Draft Preparation, D.K.; Writing-Review and Editing, Y.-K.K. and S.-Y.K.; Visualization, D.K.; Supervision, D.K.; Project Administration, D.K.; Funding Acquisition, D.K.

**Funding:** This research was funded by a two-year research Grant of Pusan National University, Ministry of Environment, Busan Municipal Government.

**Conflicts of Interest:** The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

### **References**


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International Journal of *Environmental Research and Public Health*
