Objective:To discuss the association between occupational acid fog exposure and accelerated biological aging of the workers,and to clarify its related risk factors.Methods:A total of 341 male workers exposed to occupational acid fog and 201 male workers without occupational exposure were selected as the study subjects,and they were divided into exposure group and control group,respectively.The general informations of the subjects in two groups were collected through questionnaires and physical examinations.The levels of red blood cell count(RBC),platelet count(PLT),albumin(ALB),urea(Urea),creatinine(CR),triglycerides(TG),total cholesterol(TC),glycated hemoglobin(HBA1c),and high-sensitivity C-reactive protein(Hs-CRP)in serum of the subjects in two groups were detected.The Klemera-Doubal method(KDM)was used to construct the composite aging measure,KDM-biological age(BA)(KDM-BA).The model parameters were trained using samples from the 2009 China Health and Nutrition Survey(CHNS)Database to calculate the BA acceleration of the subjects in two groups;stratified analysis based on the population characteristics was conducted to analyze the BA of the subjects in two groups with different population characteristics;generalized linear model was used to analyze the factors influencing BA acceleration due to acid fog exposure.Results:The model parameters were trained using samples from the 2009 CHNS Database,including 8 133 cases aged 20-79 years,of which 3 788 were male.The levels of Urea,CR,HBA1c,ALB,and TC,as well as systolic blood pressure(SBP),total working years,sleep duration,and body mass index(BMI)of the subjects between two groups had significant differences(P<0.05).Compared with control group,the BA acceleration of the subjects in exposure group was significantly increased(P<0.05).In entire population and exposure group,the BA acceleration in the smokers was significantly higher than that in the non-smokers(P<0.05).In entire population,control group,and exposure group,the BA accelerations of the subjects in different BMI groups were significantly decreased with the increase of BMI(P<0.05).Compared with control group,the BA acceleration of the subjects in exposure group was significantly increased(P<0.05),including those under 40 years old,with total working years of 4-7 years,Han nationality,unmarried,smokers,and sleep duration 6-7 h,and with overweight.Acid fog exposure,smoking,and BMI were associated with the BA acceleration(β=0.72,95%CI:0.24-1.21;β=0.59,95%CI:0.11-1.06;β=-0.29,95%CI:-0.35—-0.22).Conclusion:Occupational acid fog exposure may accelerate the biological aging in the workers,and acid fog is a risk factor to accelerate the biological aging of the body.

OBJECTIVE: To study the combined effect of noise and hydrogen cyanide on noise-induced hearing loss( NIHL)in a metal electroplating enterprise. METHODS: The judgment sampling method was used to select 663 workers in a largescale metal electroplating enterprise as the study subjects. Among them,186 workers exposed to noise alone were designated as noise group; 138 workers exposed to hydrogen cyanide alone were designated as hydrogen cyanide group; and161 workers exposed to noise and hydrogen cyanide were designated as combined effect group,and 178 workers without exposure from occupational disease risk factors were designated as control group. Questionnaires survey and pure tone audiometry were used for analyzing the effects of combined noise and hydrogen cyanide exposure on NIHL. RESULTS: The hearing loss detection rate of the study subjects was 40. 4%. The hearing loss detection rates in the control group,noise group,hydrogen cyanide group,and combined effect group were 17. 4%,47. 8%,32. 6% and 64. 0%,respectively. The detection rate of hearing loss in the control group was lower than that in the other three groups( P < 0. 008). The NIHL detection rates in the combined effect group and the noise group were higher than that in the hydrogen cyanide group( P <0. 008). The hearing loss detection rate of the combined effect group was higher than that of the noise group and the hydrogen cyanide group( P < 0. 008). Ordinal multi-categorical logistic regression model results showed that after adjusting confounding factors such as age,length of service,gender,marital status,smoking,alcohol drinking,we found hydrogen cyanide exposure,noise exposure,and combined exposure to hydrogen cyanide and noise had effects on workers' hearing(P < 0. 05). The risk of hearing loss in workers exposed to noise and hydrogen cyanide was higher than that of workers exposed to noise alone or hydrogen cyanide alone. CONCLUSION: There is a combined effect of noise and hydrogen cyanide in this metal electroplating enterprise,which can increase the risk of NIHL in workers.

OBJECTIVE：To explore the metabolic charact eristics of Miao medicine Laportea bulbifera extract in isolated human intestinal flora. METHODS ：L. bulbifera was extracted with 70％ ethanol reflux extraction. After concentration，extraction with n-butanol and drying ，L. bulbifera extract was obtained. Taking 0.05 g/mL L. bulbifera extract 1 mL mixed with isolated human intestinal flora fluid 10 mL and cultured for 36 h in anaerobic environment （setting up blank control without drugs or human intestinal bacterial solution ），so as to simulate the metabolic process of the extract in human intestine. The metabolites were detected by UPLC-Q-TOF/MS. The determination was performed on Agilent Eclipse Plus C 18 RRHD column with mobile phase consisted of 0.01％ formic acid water solution- 0.01％ formic acid acetonitrile solution （gradient eluetion ）at the flow rate of 0.25 mL/min. The column temperature was set at 40 ℃，and the sample size was 1 µL. ESI detection was adopted and scanned by negative ion mode （ESI－）；the capillary voltage was 4.5 kV，the ion source temperature was 120 ℃，the collision energy was 15-32 V，and the scanning range was m/z 50-1 000. The “Strip”module of MassLynx V 4.1 software was used to analyze the differential chromatograms between the reaction solution and the blank control of L. bulbifera extract. Mass spectrum data and UNIFI so ftware were used to predict relative molecular weight and formula ；based on the information of substance control and related literature reports ， the structure and biotransformation pathway of L. bulbifera metabolites in isolated human intestinal flora were predicted and analyzed. RESULTS & CONCLUSIONS ： A total of 3 prototype ： products（rutin，quercetin，kaempferol-3-O-rutinoside）and 22metabolites （mainly the metabolites of quercetin ，mono- caffeoylquinic acid ，isoquercitrin，etc.） were detected after metabolized in isolated human intestinal flora. Itsbiotransformation pathway is phase Ⅰ reaction，which mainly consisted of reduction ，oxidation and hydrolysis.