Funding for this research was provided by:
Environmental Protection Administration, Executive Yuan, R.O.C. Taiwan (EPA-102-U1F1-02-105)
Received: 19 July 2017
Accepted: 5 January 2018
First Online: 15 January 2018
: The study protocol was reviewed and approved by a Grant Review Committee of the Environmental Protection Administration of the Taiwan government, and participation of human subjects did not occur until after informed consent was obtained.
: Not applicable.
: The authors declare that they have no competing interests.
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