RESUMO
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.
RESUMO
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.