[Research on the determination of the limit value of perchlorate in the "Standards for Drinking Water Quality（GB5749-2022）" in China].

Perchlorate is an environmental pollutant that has been a focus of attention in recent years. It has been detected in many environmental water bodies and drinking water in China, with a high level of presence in some areas of the Yangtze River Basin. The human body may ingest perchlorate through exposure pathways such as drinking water and food, and its main health effect is to affect the thyroid's absorption of iodine. The "Standards for Drinking Water Quality" (GB5749-2022) includes perchlorate as an expanded indicator of water quality, with a limit value of 0.07 mg/L. This article analyzes the technical content related to the determination of hygiene standard limits for perchlorate in drinking water, including the environmental presence level and exposure status of perchlorate, main health effects, derivation of safety reference values, and determination of hygiene standard limits.

[Research on the standard limits for vinyl chloride and trichloroethylene in the "Standards for Drinking Water Quality（GB5749-2022）" in China].

The usage of vinyl chloride and trichloroethylene in China has been increasing year by year, and they have been detected in both drinking water and environmental water, making them important environmental pollutants. Based on the latest research results on the health effects of vinyl chloride and trichloroethylene, the newly issued, "Standards for Drinking Water Quality (GB5749-2022)" in China has adjusted the standard limit of vinyl chloride from 0.005 mg/L to 0.001 mg/L and the standard limit of trichloroethylene from 0.07 mg/L to 0.02 mg/L. This article analyzed and discussed the relevant technical contents for determining the above standard limits, including the levels and exposure conditions of vinyl chloride and trichloroethylene in the water environment, health effects, derivation of safety reference values, and determination of hygiene standard limits. Suggestions were also made for the implementation of this standard.

[Methodological study on the establishment of limit values in the Standards of Drinking Water Quality].

The establishment of limit values for standards of drinking water quality is an important and complex process. This study systematically introduced the methodology of the establishment of standard limit values for drinking water quality and elaborated on the workflow of setting limit values of water quality indicators, principles and methods of selecting water quality indicators, derivation of safety reference values, and establishment of limit values. It also aimed to provide reference and support for the future revision of relevant standards.

[Interpretation of the limit values of iodide in the "Standards for Drinking Water Quality（GB5749-2022）" in China].

The Drinking Water Sanitation Standard (GB 5749-2022) has been officially promulgated and implemented, with the iodide listed as a new reference indicator for water quality. This study interprets the distribution of iodine in environmental media, the impact of water iodine on health, the significance of establishing iodide standard limits, and the use of iodide standard limits, in order to provide a scientific basis for the application of iodide standard limits in this revised standard.

[Study of association between drinking water and gastric cancer of the residents in Sheyang county Jiangsu Province: a case-control study].

A total of 189 new cases of gastric cancer in Sheyang County from 2014 to 2018 were selected as the case group, and 189 other people without gastric cancer were matched according to age and gender as the control group. A case-control study was conducted on the relationship between drinking water and gastric cancer. After adjusting BMI, family annual income, dietary taste, monthly pickle consumption, monthly chili consumption, monthly soy product consumption, whether experiencing misfortune, whether suffering from superficial gastritis, whether having family history of gastric cancer, the results of multivariate logistic regression showed that compared with those who had no sources of pollution at the end of drinking water 10 years ago and who mainly consumed boiled water, those who had sources of pollution at the end of drinking water 10 years ago and who only drank raw water had a higher risk of stomach cancer ï¼»OR (95%CI) were 2.20 (1.13-4.29), 6.12 (1.25-29.93)ï¼½; Compared with drinking water source from tap water, the risk of stomach cancer of those who drink clean water is lower ï¼»OR (95%CI): 0.55 (0.35-0.85)ï¼½; And those who drink more water every day have a lower risk of stomach cancer ï¼»OR (95%CI): 0.67 (0.48-0.92)ï¼½.