[Distribution Characteristics of Mercury in Reed Leaves from the Jiapigou Gold Mine in the Songhua River Upstream].

At the Jiapigou gold mine of the Songhua River upstream, reed leaves (Phragmites australis), soil, and water samples were collected from June (summer) and September (autumn) 2016 for the determination of mercury. Moreover, the mercury concentrations in the air were determined synchronously. Furthermore, the level of mercury pollution in the reed leaves was determined by a single factor pollution index method, and the relationships among mercury concentrations in the reed leaves and environmental factors were analyzed to research the distribution characteristics, influencing factors, and correlations around the gold mining area. The results show that, in terms of spatial distribution, the mercury concentrations in reed leaves, soil, and water gradually decay with the distance from the gold mining area, and the spatial distribution of the mercury concentrations in the air was not obvious. Regarding a temporal distribution, the mercury concentrations in the reed leaves in summer were lower than those in autumn in the heavy pollution areas, while the distribution in the light pollution areas was the opposite, as the mercury concentrations of air and soil in summer were higher than those in autumn. The influence of environmental factors on the mercury concentrations in the reed leaves was soil > air > water. In addition, after stopping gold mining and processing using mercury, the mercury source in the area was the soil.

Characteristics of patients on methadone maintenance treatment in Taizhou City / 预防医学

Objective To investigate the characteristics of methadone maintenance treatment(MMT)clients, and to explore their retention rate and associated factors in Taizhou, Zhejiang Province. Methods Heroin or opiate addicts who started MMT between 2006 and 2014 in study area were included. Data including demographics, history of drug use and treatment information was extracted from the National MMT Data Management System and descriptive analysis were conducted. Multiple logistic regression models were used to explore factors associated with retention rate. Results In total, 2 262 MMT clients were included for analysis. Most of them were male(87.53%), single, divorced or widowed(55.75%), and had an education of junior middle school or below(88.68%). Almost all of them (98.32%)were heroin addicts, and the age at first drug use ranged from 9 years to 54 years, with average age of(25.06±6.34)years. A total of 1 123(49.65%)clients had a history of inject drug use and 81(3.58%)clients had ever shared needles with others. The average duration on MMT was 5.02±2.01 years, and the average methadone dosage during treatment was (34.49 ±22.69)mL. The MMT retention rate was 29.2% (661/2 262). In multivariable analysis, districts such as Huangyan District, Yuhuan County and Linhai City, aged≥40 years and average methadone dosage>20 mL during treatment were independently and positively associated with retention rate. Conclusion Most of MMT clients in Taizhou are male, unmarried, and had low education level. The retention rate is low in Taizhou but older patents and those receive high methadone dosage have a relatively higher retention rate.