This study was conducted between November to December 2020, consisting of six representative cities, Beijing, Shanghai, Shenzhen (with comprehensive smoke-free legislation), and Changsha, Chongqing, Shenyang (without comprehensive smoke-free legislation), 678 subjects were enrolled eventually, the mean age of the 678 subjects was (35.61±12.91)years old. Subjects from cities with comprehensive smoke-free legislation accounted for 49.71% of the total; male subjects accounted for 19.47%; meanwhile subjects from large, medium, and small restaurants accounted for 13.57% (92), 37.32% (253) and 49.11% (333) respectively. The analysis results indicate that the positive rate of restaurants staff of cotinine and 3'-hydroxynicotinine was lower in cities with comprehensive smoke-free legislation(34.12% vs 68.04%, χ²=78.01, P<0.001; 16.32% vs 41.94%, χ²=53.79, P<0.001), with staff from cities with comprehensive smoke-free legislation have lower concentrations of cotinine and 3'-hydroxynicotinine than their counterparts from cities without comprehensive smoke-free legislation(0.250 ng/ml vs 0.742 ng/ml, P<0.001; 0.250 ng/ml vs 0.250 ng/ml, P<0.001). No statistically significant difference in the concentration of cotinine and 3'-hydroxynicotinine in saliva between staff from restaurants of different sizes was detected (P>0.05).
2020年11—12月，纳入北京、上海、深圳（已出台全面无烟立法）和长沙、重庆、沈阳（未出台全面无烟立法）6城市的678名餐饮场所工作人员为研究对象，年龄为（35.61±12.91）岁；已出台全面无烟立法城市者占49.71%（337名）；男性占19.47%（132名）；大、中和小型餐饮场所的研究对象分别占13.57%（92名）、37.32%（253名）和49.11%（333名）。经检测研究对象的唾液样本中的可替宁和三羟基可替宁，已出台全面无烟立法城市对象唾液中可替宁［34.12%（115/337）］、三羟基可替宁检出率［16.32%（55/337）］均低于未出台全面无烟立法城市对象的可替宁［68.04%（232/341）］、三羟基可替宁检出率［41.94%（143/341）］（P值均<0.001）；已出台全面无烟立法城市对象唾液可替宁和三羟基可替宁浓度（0.250 ng/ml、0.250 ng/ml）均低于未出台全面无烟立法城市对象唾液可替宁和三羟基可替宁浓度（0.742 ng/ml、0.250 ng/ml）（P值均<0.001）；不同规模餐饮场所对象可替宁和三羟基可替宁浓度差异没有统计学意义（P值均>0.05）。.