Received: 26 April 2020
Accepted: 31 August 2020
First Online: 15 September 2020
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of People’s Government of Zhejiang Province, and Zhejiang Food and Drug Administration approved the study before data collection. The participants were informed of the aims of our study prior to participation. All participants provided signed written informed consent forms.
: All authors agree to publish.
: The authors have declared that no competing interests exist.