Objective: To obtain the dietary exposure of lead in primary, middle and high school students, and to provide basic foundation for food safety risk assessment and management for children and adolecsents. Methods: Weighing method, 3-days hour dietary survey, combining with the food frequency questionnaire, was applied to obtain basic dietary data in 616 primary, middle and high school students selected through multi-stage randdom sampling method from Pudong new area of shanghai. Data on lead concentrations were derived from the food safety risk monitoring system, which included 1 145 samples. Results: Lead was detected in 568 of 1 145 samples (49.61%) from 10 categories of foods. The exceeding standard rate was 3.58% (41 samples exceeded). The average content of lead was (0.12±0.25) mg/kg, fungi and algae, beans and the aquatic products were found to be the primary food sources of lead exposure. The average dietary lead exposure in primary, middle and high school students was 9.94 μg/kg per week, accounted for 39.76% of PTWI. The lead exposure level at the 97.5th percentile which accounted for 118.24% of PTWI was 29.56 μg/kg. Vegetables, beans and cereal foods were the mainly source of dietary lead exposure, with average dietary lead exposure 2.57, 2.44 and 1.43 μg/kg peer week, accounted for 10.26%, 9.76% and 5.74% of PTWI, respectively. Conclusion Lead is present in some foods available in local markets in Pudong New Area, Shanghai. Low level of dietary exposure to lead is found in primary, middle and high school students, however, it depends on dietary pattern. Continued efforts are needed to reduce the dietary exposure of lead in school students.

Objective: To understand 24 h physical activity levels of children aged 8-9 years in Pudong New Area and to explore its association with metabolic syndrome, so as to provide scientific basis for children s participation in physical activities and reducing the risk of metabolic syndrome. Methods: A stratified cluster random sampling method was adopted to select 13 schools in Pudong New Area, Shanghai. A total of 2 013 primary school students aged 8-9 years old were included as the research subjects. During September 2021 to December 2022, Actigraph GT3X accelerometer, height measuring gauge, electronic sphygmomanometer and waist circumference tape was used to measure physical activity, height, blood pressure and waist circumference, respectively. A total of 5 mL of venous blood was collected from students, and the levels of triglycerides (TG), highdensity lipoprotein cholesterol (HDL-C) and fasting plasma glucose (FPG) were detected, and online questionnaires were conducted. The ttest and oneway ANOVA were employed to compare the differences in 24 h physical activity levels among children with different characteristics. Multivariate Logistic regression was used to analyze the association between the 24 h physical activity levels and metabolic syndrome as well as its components. Results: Among primary school students, the average daily time of moderate to vigorous physical activity (MVPA) was (34.25±13.49)min, the attainment rate was 1.59%. The average daily sleep (SLP) time was (538.27±28.53) min, attainment rate was 1.89%. The detection rates of metabolic syndrome, abdominal obesity (AO), elevated blood pressure (BP), elevated TG, low HDL-C, and elevated FPG were 2.48%, 34.53%, 10.38%, 10.73%, 1.24% and 0.70%, respectively. Multivariate Logistic regression analysis showed that, for every 10minute increase in sedentary behavior (SB) time, the risks of AO, elevated BP, and elevated TG increased by 2% ( OR=1.02, 95%CI =1.01-1.04), 5% ( OR=1.05, 95%CI =1.01-1.08), and 6% ( OR= 1.06, 95%CI =1.02-1.11), respectively ( P <0.05). For every 10minute increase in MVPA time, the risk of metabolic syndrome decreased by 27% ( OR=0.73, 95%CI=0.57-0.93, P <0.05). For every 10 minute increase in SLP time, the risks of AO, elevated BP, and metabolic syndrome decreased by 16% ( OR=0.84, 95%CI =0.80-0.88), 9% ( OR=0.91, 95%CI =0.82- 0.99 ), and 15% ( OR=0.85, 95%CI =0.77-0.94), respectively （P <0.05). Conclusions The time of MVPA and SLP are seriously insufficient among children aged 8-9 years in Pudong New Area. There is an association between physical activity levels and metabolic syndrome as well as its components. Increasing the time of MVPA and SLP is of great significance for maintaining a relatively low risk of metabolic syndrome in children.

Objective To evaluate the characteristics of exposure to micro- and nano-plastics （MPs） via food ingestion and inhalation among Chinese children including 6-7 years old school children in Pudong New Area of Shanghai. Methods Articles published until March 2021 were searched on PubMed， Web of Science， Scopus， China National Knowledge Infrastructure （CNKI）， Wanfang and Weipu databases. The exposure levels of MPs by food ingestion and inhalation pathways were estimated by referring to the Chinese children food consumption and breathing rates data. The characteristics of children’s exposure to MPs in China were compared with that in the United States. In addition， the consumption of bottled water， tap water and salt intake among children aged 6-7 years was determined in a cohort of children and adolescents in Pudong New Area of Shanghai. The characteristics of exposure to MPs through food intake and inhalation among them were investigated. Results A total of 5 786 samples from 38 studies were retrieved. Annual intake of MPs among Chinese children was estimated to range from 159 400 to 204 637 MPs from food ingestion， depending on age and sex. When inhalation exposure is also considered， the annual MPs intake increased to 164 635 to 213 032 MPs， which were larger than the values in American persons. Ingestion of MPs posed the largest health risk to male Chinese adults. With the questionnaire survey data， the estimated annual total exposure amount through food intake alone is 116 272‒120 334 MPs for 6 to 7 years old school children in Pudong New Area. With addition of inhalation exposure， the annual total exposure amount is 121 300‒125 983 MPs， which is lower than the average exposure level in the whole country. The discrepancy could be mainly due to the different drinking habits between the local children and others. Overall， tap drinking water， seafood，bottled water， and air represented four substantial vectors of daily MPs exposure in Chinese children. Conclusion Ingestion and inhalation of MPs pose higher health risk to Chinese children in comparison to American children. The level of exposure to MPs among 6 to 7 years old school children in Pudong New Area of Shanghai is lower than that in the same age group of children across the whole country. The attempt to lower the MPs levels in drinking water and seafood would represent the most effective means to help reduce the MPs exposure risk to Chinese children.

Background Papillary thyroid cancer is the result of a variety of pathogenic factors. The prevalence of papillary thyroid cancer varies greatly in different regions, and the disease is more harmful to women. Objective This study aims to explore the relationship between reproductive factors and papillary thyroid cancer, and to provide basic data for prevention and control of the disease. Methods A 1∶1 age (±3 years) matched case-control study was conducted in 331 pairs of newly confirmed papillary thyroid cancer cases and controls from two hospitals in Shanghai from November 2012 to December 2013. Comparisons were made in the history of menstruation, pregnancy, gynecological and breast diseases, and other variables between the two groups. Results The results of univariate analysis indicated that the proportions of education below bachelor degree, married, and mainly manual workers in the case group were significantly higher than those in the control group (P<0.05); the proportion of those with a family history of thyroid diseases in the case group was significantly higher than that in the control group (P<0.05); the proportions of the cases with irregular menstruation (77.34%), a history of using oral contraceptive or hormone drugs (24.77%), a history of benign gynecological diseases (31.72%), and a history of gynecological surgery (9.67%) were significantly higher than the proportions in the control group (P<0.05). After adjusting potential confounding factors such as history of CT examination, age, kinds of family salt, total iodine intake every day, education level, occupation, marital status, body mass index, and family history of thyroid diseases, the results of multiple logistic regression analysis showed that irregular menstruation (OR=1.767, 95%CI: 1.122-2.782; P=0.014), surgical menopause (OR=12.787, 95%CI: 3.202-51.057; P<0.001), pregnancy >1 time (OR =2.490, 95%CI: 1.196-5.184; P=0.015), and the history of using oral contraceptive or hormone drugs (OR=2.389, 95%CI: 1.338-4.268; P=0.003) were the risk factors of papillary thyroid cancer. Conclusion Irregular menstruation, surgical menopause, history of pregnancy, and history of using oral contraceptive or hormone drugs might be the risk factors of papillary thyroid cancer. To reduce the incidence of papillary thyroid cancer, strengthened health education and rational use of contraceptives are recommended.

【Objective】 To understand the prevalence of overweight/obesity among school-age children in Pudong New Area of Shanghai, and to explore the influence of gestational weight gain and pre-pregnancy body mass index (BMI) on weight status of school-age children. 【Methods】 From November to December 2020,a stratified cluster sampling method was adopted to select first-grade students from 13 primary schools in Pudong New Area of Shanghai.After matching with the birth monitoring database, 755 students with complete birth information were selected as the study subjects.The relevant information of mothers before and during pregnancy was retrospectively collected, and the effects of pregnancy weight gain combined with pre-pregnancy BMI on overweight/obesity in school-age children were analyzed. 【Results】 1) The prevalence rates of overweight and obesity of first-grade children were 15.89% and 18.41%, respectively.2) Maternal excessive weight gain during pregnancy (OR=1.678) and overweight/obesity before pregnancy (OR=2.315,2.412) were risk factors for overweight/obesity of the offspring at school age(P<0.05).3) For mothers who were underweight before pregnancy, excessive weight gain during pregnancy was associated with overweight/obesity in school-age children in their offspring (OR=7.436, 95%CI: 1.489 - 37.143,P<0.05).4) Excessive weight gain during pregnancy combined with overweight/obesity before pregnancy significantly increased the risk of overweight/obesity in offspring (OR=3.606, 95%CI: 2.030 - 6.405, P<0.05). Mothers who gained a moderate amount of weight during pregnancy and were emaciated before pregnancy had a significantly lower risk of overweight/obesity in their school-age children (OR=0.217, 95%CI: 0.049 - 0.967, P<0.05). 【Conclusion】 Excessive weight gain during pregnancy increases the risk of overweight/obesity in school-age children in their offspring, strengthening pregnancy health education and perinatal care to help pregnant women maintain appropriate weight gain during pregnancy may be an important and novel strategy to prevent childhood obesity.