1.Distribution and health risk assessment of nitrosamines in drinking water in Shanghai
Hongquan CAI ; Hailei QIAN ; Zhiyi XUE ; Saifeng PEI ; Yun ZHANG ; Chaoye SHEN
Journal of Environmental and Occupational Medicine 2022;39(7):752-757
Background Nitrosamines (NAms) are highly carcinogenic and frequently detected in drinking water systems in China, indicating potential human health risk through drinking water. Objective To analyze the distribution of NAms in drinking water in Shanghai and to evaluate relevant human health risk. Methods A total of 94 samples of source water and 120 samples of finished water were collected in February (dry period) and August (wet period) of 2021 from 30 drinking water plants in Shanghai, and eight NAms were quantitatively analyzed by gas chromatography tandem mass spectrometry after solid phase extraction. Cancer risks for different age groups caused by NAms exposure through water were evaluated using Monte Carlo probabilistic method and carcinogens risk assessment model recommended by the United States Environmental Protection Agency. Results The concentrations of total NAms in source and finished water were 12.56-65.86 ng·L−1 and 8.52-57.38 ng·L−1, respectively. The average concentration of total NAms was higher in source water (33.50 ng·L−1) than in finished water (22.07 ng·L−1, P<0.05) during dry season, and lower in source water (16.90 ng·L−1) than in finished water (21.02 ng·L−1, P<0.05) during wet season. The average concentration of total NAms in source water during dry season was twice of that during wet season. The positive rate of N-nitrosodimethylamine (NDMA) was the highest (100%) among the eight NAms. The cancer risk of exposure to NAms in finished water in Shanghai was mainly from the ingestion route, which was mostly caused by NDMA. The cancer risk from exposure to NAms in water for children (median=4.32×10−5) was slightly higher than that for adults (median=3.34×10−5) and adolescents (median=2.27×10−5). The cancer risks of exposure to NAms in water for people of different ages were mainly (80% - 95%) at an acceptable level (1×10−6 - 1×10−4). Conclusion NAms contamination is positive in Shanghai’s drinking water and NDMA is the main contaminant. The removal of NAms in water by current water treatment process is season-dependent. The cancer risk of children exposed to NAms in water was slightly higher than that of adults and adolescents, but all at acceptable levels.
2.Assessment of intervention measures on trihalomethane in finished water by interrupted time series analysis
Yangyang REN ; Hailei QIAN ; Saifeng PEI ; Xiaodong SUN ; Zheng WU ; Chen WU ; Jingxian ZHOU ; Aimin DU ; Shaofeng SUI
Journal of Environmental and Occupational Medicine 2024;41(4):420-424
Background The Qingcaosha Reservoir is facing issues of algal blooms and eutrophication, and the resulting increase in the level of chlorination disinfection by-products in the water has been a major concern. Objective To evaluate the impact of "Algae Monitoring and Control Program in Qingcaosha Reservoir" (hereinafter referred to as the program) on the control of trihalomethanes (THMs) in conventional finished water. Methods From 2011 to 2019, water samples were collected from the Lujiazui Water Plant once per season, one sample each time, and the concentrations of four THMs (trichloromethane, dichlorobromomethane, monochlorodibromomethane, and tribromomethane) were measured in the samples. Using 2014 when the program was implemented as a cut-off point, the entire study period was divided into two phases: pre-implementation (2011–2013) and post-implementation(2014–2019). Segmented linear regression with interrupted time series analysis was applied to assess the concentrations and trends of THMs in the finished water before and after the program launch. Results The concentration of total THMs in finished water increased by 1.561 µg·L−1 (P=0.010) for each season of time extension before launching the program. The change in the concentration of total THMs in finished water was not statistically significant after the program launch, but the THMs concentration showed a decreasing trend as the slope was −0.626 (P=0.001). From 2017 until the end of 2019, the average concentration of THMs in finished water of Lujiazui Water Plant dropped to 10 μg·L−1 or less. Conclusions The algae and eutrophication control measures in Qingcaosha Reservoir have achieved good results, controlling THMs in finished water at a low level, and the trend of THMs has changed from a yearly increase pattern before the program to a yearly decrease pattern after the program.
3. Analysis on influencing factors of deaths from severe heat stroke in Shanghai, 2013-2017
Meizhu PAN ; Huihui XU ; Chunyang DONG ; Xiaodan ZHOU ; Jianghua ZHANG ; Hailei QIAN
Chinese Journal of Preventive Medicine 2019;53(1):93-96
Objective:
To explore the related factors of death from severe heat stroke in Shanghai from 2013 to 2017.
Methods:
The data of 1 152 patients with severe heat stroke who were divided into survival (
4.Clinical efficacy of ex vivo liver resection and autotransplantation for liver complex space-occupying lesions
Junjie SHU ; Yi GONG ; Xia OU ; Haisu DAI ; Chengcheng ZHANG ; Wei LIU ; Hailei CHEN ; Xiangde LIU ; Zhanyu YANG ; Qian LU ; Leida ZHANG ; Ping BIE
Chinese Journal of Digestive Surgery 2020;19(8):869-875
Objective:To investigate the clinical efficacy of ex vivo liver resection and autotransplantation (ELRA) for liver complex space-occupying lesions.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 50 patients with liver complex space-occupying lesions who underwent ELRA in the First Hospital Affiliated to Army Medical University between June 2009 and May 2017 were collected. There were 36 males and 14 females, aged from 13 to 69 years, with a median age of 51 years. All patients underwent ELRA. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) follow-up. Follow-up was conducted by outpatient examination or telephone interview. Patients were followed up according to the individual follow-up plan in the first 6 months after discharge, and then once every 3 to 6 months to detect tumor recurrence and survival up to May 2019. Measurement data with normal distribution were represented as Mean± SD. Measurement data with skewed distribution were represented as M (range). Count data were expressed as absolute numbers or percentages. The Kaplan-Meier method was used to calculate survival rates and draw survival curves, and Log-rank test was used for survival analysis. Results:(1) Surgical situations: all the 50 patients underwent ELRA successfully, and postoperative pathological examination showed the R 0 resection rate was 100%(50/50). The operation time of the 50 patients were (630±186)minutes, of which 9 patients with liver benign occupation had the operation time of (684±168)minutes and 41 patients with liver malignant tumor had the operation time of (618±190)minutes. The operation time of temporary reconstruction of inferior vena cava and portacaval shunt, time of anhepatic phase, volume of intraoperative blood loss of the 50 patients were (35±9)minutes, (256±71)minutes, 2 000 mL(range, 400-10 000 mL), respectively. The remnant liver mass to standard liver mass ratio of the 50 patients was 65%±16%, of which 9 patients with liver benign occupation had the remnant liver mass to standard liver mass ratio of 63%±14% and 41 patients with liver malignant tumor had the remnant liver mass to standard liver mass ratio of 65%±17%. Of the 50 patients, 35 had vascular invasion (7 cases with liver benign occupation, 28 cases with liver malignant tumor), of which 24 (6 cases with liver benign occupation, 18 cases with liver malignant tumor) underwent in vitro vascular reconstruction, 12 (5 cases with liver benign occupation, 7 cases with liver malignant tumor) had bile duct invasion and underwent choledochojejunostomy due to the inability of the common bile duct to anastomose the ends. Two cases with liver metastasis of gastric cancer, one case with liver metastasis of colon cancer and one case with liver metastasis of pancreatic cancer underwent radical gastrectomy, radical resection of colon cancer, and pancreaticoduodenectomy, respectively. (2) Postoperative situations: the duration of postoperative hospital stay of the 50 patients were 25 days (range, 11-169 days). Of the 50 patients, 12 had pleural effusion who were treated with pleural puncture drainage, 10 had bile leakage who were treated with abdominal puncture drainage, 3 had bile duct anastomotic leakage who were treated with endoscopic nasobiliary drainage or biliary stent implantation, 6 underwent reoperation among which 4 underwent exploratory laparotomy due to abdominal hemorrhage, 1 underwent portal vein reconstruction due to abdominal hemorrhage combined with portal vein thrombosis, and 1 underwent salvage liver transplantation due to liver failure. Nine of the 50 patients died within 90 days after surgery, all of whom had liver malignant tumor. Among them, 3 died of multi-organ dysfunction syndrome caused by severe infection, 3 died of acute liver failure, 2 died of abdominal hemorrhage and 1 died pulmonary embolism. (3) Follow-up: all the 50 patients were followed up for 1 to 119 months. The overall survival time, 1-, 3-, 5-year overall and tumor-free survival rates of the 50 patients after operation were 17 months (range, 1-119 months), 68.0%, 45.9%, 41.1% and 41.9%, 33.4%, 30.8%, respectively. The overall survival time, 1-, 3-, 5-year overall and tumor-free survival rates of the 9 patients who with liver benign occupation after operation were 68 months (range, 10-114 months), 88.9%, 88.9%, 88.9% and 88.9%, 88.9%, 88.9%, respectively. The overall survival time, 1-, 3-, 5-year overall and tumor-free survival rates of the 41 patients who with liver malignant tumor after operation were 15 months (range, 1-119 months), 63.4%, 36.6%, 31.0% and 31.5%, 21.0%, 18.0%, respectively. There were significant differences in the overall and tumor-free survival rates between patients who with liver benign occupation and patients who with liver malignant tumor ( χ2=7.626, 11.766, P<0.05). Conclusions:ELRA can be applied in the treatment of liver complex space-occupying lesions. The selection criteria of patients with liver malignant tumor should be more rigorous to reduce perioperative mortality.
5.Epidemiological characteristics and influencing factor of non-occupational carbon monoxide poisoning during 2007—2018 in Shanghai
Fei’er CHEN ; Meizhu PAN ; Huihui XU ; Chunyang DONG ; Qing GU ; Qi’ang JIN ; Jianghua ZHANG ; Yewen SHI ; Hailei QIAN ; Chen WU
Journal of Environmental and Occupational Medicine 2022;39(8):878-882
Background Non-occupational carbon monoxide (CO) poisoning is a public health problem that seriously affect people’s health and lives. Objective To describe the prevalence of non-occupational CO poisoning during 2007—2018 in Shanghai, analyze its epidemiological characteristics and potential influencing factors, and explore effective prevention and control measures. Methods Daily reported non-occupational CO poisoning cases and meteorological factors from 2007 to 2018 were collected in Shanghai, epidemiological characteristics were analyzed by descriptive epidemiology methods, and a distributed lag nonlinear model was used to assess the association between temperature and non-occupational CO poisoning. Results A total of 2264 non-occupational CO poisoning events and 3866 cases from 2007 to 2018 were reported in Shanghai, including 59 death cases. More than half of the poisoning cases were female (56.3%), and young adults accounted for more cases than any other age group (54.8%). The poisoning events mainly occurred in winter (from December to next February); however, cases reported in summer increased in recent years. The peak period of the events was from 20:00 to 24:00. Households (85.2%) and restaurants (8.0%) were the common places of non-occupational CO poisoning events, and the main cause was improper use of gas water heater (36.9%). A nonlinear curve was found between daily average temperature of current day and the occurrence of non-occupational CO poisoning. Temperature was negatively associated with the risk of non-occupational CO poisoning when the temperature was lower than 9.6 ℃, while a positive association was found during 9.7-26.0 ℃. Conclusion Winter is a high season for non-occupational CO poisoning in Shanghai, rising cases reported in summer is also worthy of attention. Supervision should be strengthened to ban sales of unqualified gas water heaters, and health education on CO poisoning prevention and control should be conducted through multiple channels, in order to reduce the incidence of CO poisoning.
6.Effects of heat waves on heat stroke in Shanghai, 2013—2023
Fei’er CHEN ; Chunyang DONG ; Jianghua ZHANG ; Hailei QIAN ; Zheng WU ; Yewen SHI ; Xiaodong SUN
Journal of Environmental and Occupational Medicine 2024;41(6):610-616
Background The substantial health damage attributed to heat waves, along with their increasing intensity and frequency in the context of global warming, highlights the importance of exploring the health effects of heat waves. Objective To calculate the excess heat stroke cases during heat waves in the summer of 2013—2023 in Shanghai, analyze the association between heat waves and heat stroke, and to further explore the modifying effects of heat wave characteristics on heat stroke. Methods Using a retrospective ecological study design, data on heat stroke cases were collected from the heat stroke case reporting system of the Chinese Center for Disease Control and Prevention, and concurrent meteorological data from Xujiahui Meteorological Station. A heat wave was defined as at least 3 consecutive days with daily maximum temperature meeting or exceeding 35 ℃ in this study, excess heat stroke cases related to heat waves were assessed as the difference between the numbers of heat stroke cases observed on a given day and the corresponding 31 d (15 d before and after that day) moving average, and statistical analyses using generalized linear model based on time series study were performed to assess the impact of heat waves on heat stroke. Results Overall 25 heat waves during the study period were observed, leading to a total of estimated 792.6 extra heat stroke cases. The risk of heat stroke significantly increased during heat waves (RR=2.60, 95%CI: 2.08, 3.26), but no statistically significant differences in heat wave effects were observed among different genders, ages, or regions. In terms of the timing of heat waves, the risk of heat stroke was highest during the first heat wave (RR=3.58, 95%CI: 2.82, 4.55), which was significantly higher than that during the second heat wave (RR=2.19, 95%CI: 1.66, 2.90), and no significant effect was observed during the third or subsequent heat waves. The impact of heat waves on heat stroke persisted for more than 4 d, with the risk higher on the fourth day and beyond (RR=2.95, 95%CI: 2.28, 3.83), significantly higher than on the first day of heat wave (RR=1.74, 95%CI: 1.18, 2.56). Conclusion Heat waves had a substantial effect on heat stroke in Shanghai from 2013 to 2023, and special attention need to be paid to heat waves with early onset and long duration.