Background and aim:Few studies have reported hepatitis B surface antigen(HBsAg)kinetics after nucleos(t)ide analog(NA)discontinuation in patients with noncirrhotic chronic hepatitis B(CHB).The study specifically investigated long-term HBsAg kinetics after NA discontinuation. Methods:Between January 2014 to January 2024,this study prospectively enrolled 106 outpatients with noncirrhotic CHB who met the discontinuation criteria after NA consolidation treatment.Demographic,clinical,and laboratory data were collected and analyzed after NA discontinuation. Results:Ninety-six patients who finished 5 years of follow-up were included.HBsAg remained unde-tectable in 29 patients with end of treatment(EOT)HBsAg negativity.Among 67 patients with EOT HBsAg positivity,HBsAg seroclearance occurred in 12(17.9％)patients with an estimated annual inci-dence of HBsAg seroclearance of 3.6％.Patients with EOT HBsAg levels of ≤1000 IU/mL had a higher HBsAg seroclearance rate than those with EOT HBsAg levels of＞1000 IU/mL(33.3％vs.5.4％).The pro-portion of patients with HBsAg ≤1000 IU/mL increased during follow-up.Logistic regression analysis indicated that the EOT HBsAg level was an independent factor for HBsAg seroclearance and an HBsAg level decline exceeding 1 log10 IU/mL.The optimal EOT HBsAg cutoff for both HBsAg seroclearance and an HBsAg level decline exceeding 1 log10 IU/mL was 359 IU/mL. Conclusions:Patients with EOT HBsAg negativity experienced no relapse and maintained HBsAg sero-clearance during 5 years of follow-up after NA discontinuation.A higher HBsAg seroclearance rate can be obtained in patients with EOT HBsAg levels of ≤1000 IU/mL during 5 years of follow-up after NA discontinuation.Close monitoring and proper NA retreatment are recommended to guarantee the safety of NA discontinuation.

Objective To investigate the operation status and service level of radiation occupational health inspection institutions in Zhejiang Province, China, and to provide a basis for administrative departments and quality management departments to develop policies. Methods The investigation data of radiation occupational health inspection institutions in Zhejiang Province were collected for descriptive analysis of the regional distribution, nature, and service qualification of the institutions. Results There were 27 radiation occupational health inspection institutions in Zhejiang Province. These institutions were located in 11 cities, of which 85.18% were public institutions and 14.72% were private institutions. For the physical examination workload of radiation workers in Zhejiang Province in 2021, general hospitals accounted for 75.90%, private institutions accounted for 4.51%, and occupational prevention and treatment hospitals accounted for 19.59%. In the radiation occupational health inspection institutions, the stand-alone and online software installation rates were 33.33% and 37.04%, respectively. A total of 26 986 individuals (82.97%) underwent chromosome aberration examination. The examination rates of thyroid color Doppler ultrasound examination and eye lens examination were 41.24% and 82.97%, respectively. Pre-job, on-job, and off-job physical examination accounted for 25.81%, 70.52%, and 3.67%, respectively. For radiation workers who underwent on-job physical examination, diagnostic radiology workers accounted for the highest proportion of 34.90%. The excellent, qualified, and unqualified rates of 27 radiation occupational health inspection institutions were 7.41%, 88.89%, and 3.70%, respectively. Conclusion The network of radiation occupational health inspection institutions in Zhejiang Province is well-established and located mainly in general hospitals, occupational prevention and control institutions, and private institutions. To enhance the quality and proficiency of occupational health examinations, it is imperative to prioritize self-improvement and management, reinforce law enforcement supervision, actively engage in blind sample assessments, and advance the application of information technology and standardized services.

Objective To investigate the current situation of occupational health of radiation workers in Zhejiang Province, China, and to provide a theoretical basis for the improvement of standards and management systems for occupational health examinations of radiation workers. Methods Data of occupational health examination cases were collected from occupational health examination institutions, including basic information, type of physical examination (pre-job, on-job, off-job), and health examination results. The differences in occupational health examination results among different groups were analyzed, and the factors influencing occupational health of radiation workers were analyzed using a logistic regression model. Results A total of 5668 cases were collected, with 86% of the participants being male and 14% being female. Compared with the pre-job group, the on-job group showed an increased abnormal rate of triiodothyronine and the off-job group demonstrated an increased abnormal rate of leukocyte count (P < 0.05). Compared with the industrial group, the nuclear fuel group showed decreased abnormal rates of thyroid structure and thyroxine and an increased abnormal rate of triiodothyronine, and the medical group demonstrated an increased abnormal rate of thyroid structure (P < 0.05). The abnormal rates of thyroid structure and white blood cell count increased with the increase of working age (P < 0.05). The abnormal rates of white blood cell count, thyroid structure, triiodothyronine, and thyroid stimulating hormone were higher in female radiation workers than in male radiation workers (P < 0.05). Sex (female), radiation work history, and age were the risk factors affecting the occupational health of radiation workers (P < 0.05). Conclusion The occupational health status of radiological workers in Zhejiang Province needs to be further improved, and the occupational health management of radiological workers should be strengthened.

Objective To investigate the current situation of occupational health of radiation workers in Zhejiang Province, China, and to provide a theoretical basis for the improvement of standards and management systems for occupational health examinations of radiation workers. Methods Data of occupational health examination cases were collected from occupational health examination institutions, including basic information, type of physical examination (pre-job, on-job, off-job), and health examination results. The differences in occupational health examination results among different groups were analyzed, and the factors influencing occupational health of radiation workers were analyzed using a logistic regression model. Results A total of 5668 cases were collected, with 86% of the participants being male and 14% being female. Compared with the pre-job group, the on-job group showed an increased abnormal rate of triiodothyronine and the off-job group demonstrated an increased abnormal rate of leukocyte count (P < 0.05). Compared with the industrial group, the nuclear fuel group showed decreased abnormal rates of thyroid structure and thyroxine and an increased abnormal rate of triiodothyronine, and the medical group demonstrated an increased abnormal rate of thyroid structure (P < 0.05). The abnormal rates of thyroid structure and white blood cell count increased with the increase of working age (P < 0.05). The abnormal rates of white blood cell count, thyroid structure, triiodothyronine, and thyroid stimulating hormone were higher in female radiation workers than in male radiation workers (P < 0.05). Sex (female), radiation work history, and age were the risk factors affecting the occupational health of radiation workers (P < 0.05). Conclusion The occupational health status of radiological workers in Zhejiang Province needs to be further improved, and the occupational health management of radiological workers should be strengthened.

Background Excessive radon exposure is considered the second risk factor for lung cancer. Since the opening of the subway in a city of Zhejiang Province, the exposure level of radioactive gas radon in subway stations and its impact on occupational health have become one of the important issues of public concern. Objective To monitor the radon concentration of subways in a city in Zhejiang Province and explore the effect of radon exposure on chromosome aberration and micronuclei in the working population. Methods A total of 55 vehicle control rooms of 55 stations affiliated to two different subway lines in a city were measured for one year; the 110 ticket offices and 55 security checkpoints from the same 55 stations were measured from 16 March to 14 June. The radon concentrations were compared by job types, subway lines, and seasons referring to Measurement methods for determination of radon in environmental air (HJ 1212-2021). Peripheral blood lymphocyte chromosome aberration and micronucleus analyses were conducted in 165 subway workers from monitoring sites for three different job types, then the influencing factors were analyzed. The detection methods were adopted from the standards of Test and assessment of chromosomal aberrations on occupational health examinations for radiation workers (GBZ/T 248-2014) and Standard for the method of micronucleus detection in lymphocytes on occupational health examination for radiation workers and exposure dose estimation (GBZ/T 328-2023). Results The radon concentration range of the target subways in Zhejiang Province was 10-320 Bq·m⁻³, all lower than the national limit (≤400 Bq·m⁻³). The differences in radon radioactivity levels among different lines, job types, and time segments were statistically significant (P<0.05). The rates of chromosomal aberration and micronucleus formation among the 165 subjects were 0.224% and 0.024%, respectively. There were significant differences in the rates of chromosome aberration and micronuclei among different jobs (vehicle control room, ticket office, security checkpoint) (P<0.05), but the abnormal rates were lower than the limits of the corresponding national standard. No significant correlation was found between jobs and chromosomal aberrations or micronuclei (P>0.05). Chromosome aberration and micronuclei varied by age, subway station seniority, and smoking (P<0.05). No effect of the above factors on chromosome aberration and micronuclei was observed by logistic regression (P>0.05). Conclusion The radon concentration in the target subway system is at a normal level. The rates of chromosomal aberration and micronucleus formation vary by jobs, but both are lower than the corresponding national limits. Therefore, radon exposure has not yet caused outstanding health impact on the subway workers.