Acute effects of ambient PM2.5 on lung function among schoolchildren.

Previous studies have found that fine particulate matter (PM2.5) air pollution is associated with decreased lung function. However, most current research focuses on children with asthma, leading to small sample sizes and limited generalization of results. The current study aimed to measure the short-term and lag effects of PM2.5 among school-aged children using repeated measurements of lung function.This prospective panel study included 848 schoolchildren in Zhejiang Province, China. Each year from 2014-2017, two lung function tests were conducted from November 15th to December 31st. Daily air pollution data were derived from the monitoring stations nearest to the schools. A mixed-effects regression model was used to investigate the relationship between PM2.5 and lung function. The effect of PM2.5 on lung function reached its greatest at 1-day moving average PM2.5 exposure. For every 10 µg/m3 increase in the 1-day moving average PM2.5 concentration, Forced Vital Capacity (FVC) of children decreased by 33.74 mL (95% CI: 22.52, 44.96), 1-s Forced Expiratory Volume (FEV1) decreased by 32.56 mL (95% CI: 21.41, 43.70), and Peak Expiratory Flow (PEF) decreased by 67.45 mL/s (95% CI: 45.64, 89.25). Stronger associations were found in children living in homes with smokers. Short-term exposure to PM2.5 was associated with reductions in schoolchildren's lung function. This finding indicates that short-term exposure to PM2.5 is harmful to children's respiratory health, and appropriate protective measures should be taken to reduce the adverse effects of air pollution on children's health.

Characterization and health risk assessment of PM2.5-bound polycyclic aromatic hydrocarbons in 5 urban cities of Zhejiang Province, China.

In 2015, we measured polycyclic aromatic hydrocarbons (PAHs) in atmospheric fine particulate matter (PM2.5) collected from 5 cities in Zhejiang Province. The mean toxic equivalent quotient (TEQ) values of benzo(a)pyrene (BaP) ranged between 1.2-3.1 ng/m3. The BaP-TEQ displayed seasonal trends, such that winter > spring and autumn > summer. During the winter, the most abundant individual PAHs were 4-6ring PAHs (84.04-91.65%). The median daily intake of atmospheric PAHs ranged between 2.0-7.4 ng/day for all populations, with seasonal trends identical to that of BaP-TEQ. The 95th incremental lifetime cancer risk (ILCR) values induced by PM2.5-bound PAHs were far lower than 10-6 for all populations. The data suggested that the pollution levels in the 5 Zhejiang Province cities were higher than the Chinese National Ambient Air Quality Standard (NAAQS). In the future, relevant measures should be taken to control atmospheric PAHs, especially 4-6 ring PAHs. The data also revealed no obvious cancer risk for populations residing in these 5 cities of Zhejiang Province.

Spatiotemporal Characteristics and Health Risk Assessment of Heavy Metals in PM2.5 in Zhejiang Province.

The spatiotemporal characteristics and human health risks of 12 heavy metals (Al, As, Be, Cd, Cr, Hg, Mn, Ni, Pb, Sb, Se, and Tl) in fine particulate matter (PM2.5) in Zhejiang Province were investigated. The annual average PM2.5 concentration was 58.83 µg/m³ in 2015 in Zhejiang. Element contents in PM2.5 varied greatly with the season and locations. Al, Pb, and Mn were the most abundant elements among the studied metal(loid)s in PM2.5. The non-carcinogenic risks of the 12 elements through inhalation and dermal contact exposure were lower than the safe level for children and adults. However, there were potential non-carcinogenic risks of Tl, As, and Sb for children and Tl for adults through ingestion exposure. The carcinogenic risks from As, Be, Cd, Cr, Pb, and Ni through inhalation exposure were less than the acceptable level (1 × 10-4) for children and adults. Pb may carry a potential carcinogenic risk for both children and adults through ingestion. More attention should be paid to alleviate non-carcinogenic and carcinogenic health risks posed by particle-bound toxic elements through ingestion exposure.

[New animal hosts of rabies virus in mountain areas in Zhejiang province].

OBJECTIVE: To understand the prevalence of rabies among wild animals and the animal species in rabies epidemic areas of Zhejiang province. METHODS: One hundred and sixty samples were collected from the brain tissues of cats, stoats, Apodemus agrarius, Moschus chinensis, and Sus scrofa in Lishui and Chunan cities of Zhejiang province. Each sample was divided into four parts: cerebrum, mesencephali, cerebellum and gyms hippocampi which were used to determine the positive samples by detection of rabies virus specific antigens and nucleotides, using DFA and RT-PCR methods. RESULTS: Positive slides in the tests contained a glaring, apple green brilliance fluorescence using rabies virus specific monoclonal antibody against nucleoprotein. Using Nested-PCR method targeted at part of N gene, five positive samples were identified which consisting of four positive samples from stoats with positive ratio as 8.33% (4/48) and one positive sample from Apodemus agrarius with positive ratio as 1.75% (1/57). However, no positive result was found from cats, Moschus chinensis, and Sus scrofa samples. CONCLUSION: Rabies virus positive samples were identified from stoats and Apodemus agrarius in the mountain areas, with biological diversity in Lishui and Chunan cities of Zhejiang province, indicating that stoats and Apodemus agrarius might have played a role in human rabies and acted as host of rabies virus. In order to effectively prevent and control rabies virus under these complicated geographical and ecological environment, we must understand and evaluate the infection situation among animals in these regions.

[Epidemiological analysis on rubella cases in Songyang County in 2004].

OBJECTIVE: To know the epidemiological characteristics of rubella case reported in Songyang County in 2004, and to know new ways of rubella control. METHOD: To analyze the epidemiology on the rubella cases reported in Songyang County in 2004. RESULTS: In 2004, 195 rubella cases were reported, and the reported rubella incidence was 84.42/100,000. The rubella cases were mainly primary and middle school students,which were 180 cases. The rubella cases occurred from January to June, and 64.10% cases occurred in April. There were 12 rubella outbreaks with 181 cases in the rural areas. For the immunity history of rebulla vaccine of 181 cases, 48.07% cases were unvaccinated, 51.93% cases were unknown. The immunization coverage rate of rubella vaccine of students in rural areas (20%) was obviously lower than that of students in the urban areas (92%). CONCLUSION: The main reasons of the high rubella incidence in Songyang County in 2004 were the low coverage rate of rubella vaccine and poor living accommodation for the primary and middle school students in the rural areas, and it was effective to adopt comprehensive measures such as emergent vaccination to control rubella outbreak.