Levels, distribution, childhood exposure assessment, and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust from nine cities in China.

Household dust is an important source of premature exposure to polybrominated diphenyl ethers (PBDEs), especially for children. In this onsite study, 246 dust samples were collected from 224 households in nine Chinese cities during 2018-2019. Questionnaires were administered to explore the association between household-related information and PBDEs in household dust. The median concentration of Σ12PBDEs in household dust from 9 cities was 138 ng/g (94-227 ng/g), with the arithmetic mean of 240 ± 401 ng/g. Among the nine cities, the highest median concentration of Σ12PBDEs in household dust was found in Mianyang (295.57 ng/g), while the lowest was found in Wuxi (23.15 ng/g). BDE-71 was the most dominant congener, ranging from 42.08 % to 98.15 % of the 12 PBDE congeners among 9 cities. Three potential sources for the indoor environment were Penta-BDE, Octa-BDE commercial products, and photolytic bromine from Deca-BDEs based on the largest contribution (81.24 %). Under the moderate exposure scenario, the exposure levels through ingestion and dermal absorption for children were 7.30 × 10-1 ng/kg BW/day and 3.26 × 10-2 ng/kg BW/day, respectively. Temperature, CO2, years of residence, income, family size, household size, use of computers, heating, use of insecticide, and use of humidifiers were influential factors for PBDE concentrations in household dust. Based on the evidence of the correlation between PBDEs and these household parameters, it can be applied to reduce PBDE concentrations in household dust, which is a basis for controlling PBDEs pollution in Chinese households and protecting population health.

Levels, distribution, sources and children health risk of PAHs in residential dust: A multi-city study in China.

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) are typical residential pollutants mainly from biofuel combustion that impose inevitable risk to children. The PAHs in residential dust is universal in most Chinese households with an obvious public health concern. METHODS: In this observational study, a total of 235 residential dust samples from 8 Chinese cities (Panjin, Shijiazhuang, Lanzhou, Luoyang, Xi'an, Wuxi, Mianyang, and Shenzhen) were collected from April 2018 to March 2019, which were extracted and analyzed for 16 priority PAHs by HPLC/FD-UV. Diagnostic ratios, hierarchical clustering analysis and principal component analysis were applied simultaneously for source apportionments. Incremental lifetime cancer risk was employed to estimate children's health risks based on the assumed exposure scenarios. Spearman correlation, Mann-Whitney U test, Kruskal-Wallis H test and Partial Least Squares were used to screen the factors affecting the concentration of PAHs in residential dust. RESULTS: The median concentration of ∑16PAHs in residential dust from 8 cities was 44.11 µg/g (0.04 - 355.79 µg/g). ∑16PAHs were found both higher in dust samples in heating season and from downwind households only in Mianyang (p < 0.05). The leading two sources of PAHs were combustion processes and automobile exhaust emissions based on four principal components that accounted for 74.29 % of the total variance. Indoor air environmental factors, household characteristics, and residents' behavioral lifestyles may be the influencing factors of residential dust PAHs. The carcinogenic risk of children aged 0 - 5 years, under the moderate exposure level of PAHs in residential dust, exceeded the acceptable level (10-5 - 10-4 for dermal contact and 10-6 - 10-5 for ingestion). CONCLUSIONS: There was serious PAHs pollution in residential dust under actual living conditions in eight cities across China. More evidence-based measures were needed to control PAHs pollution to safeguard children's health according to appointed sources and influencing factors in residential dust.

Heatwave and urinary hospital admissions in China: Disease burden and associated economic loss, 2014 to 2019.

BACKGROUND: Many studies have shown that heatwaves are associated with an increased prevalence of urinary diseases. However, few national studies have been undertaken in China, and none have considered the associated economic losses. Such information would be useful for health authorities and medical service providers to improve their policy-making and medical resource allocation decisions. OBJECTIVES: To explore the association between heatwaves and hospital admissions for urinary diseases and assess the related medical costs and indirect economic losses in China from 2014 to 2019. METHODS: Daily meteorological and hospital admission data from 2014 to 2019 were collected from 23 study sites with different climatic characteristics in China. We assessed the heatwave-hospitalization associations and evaluated the location-specific attributable fractions (AFs) of urinary-related hospital admissions due to heatwaves by using a time-stratified case-crossover method with a distributed lag nonlinear model. We then pooled the AFs in a meta-analysis and estimated the national excess disease burden and associated economic losses. We also performed stratified analyses by sex, age, climate zone, and urinary disease subtype. RESULTS: A significant association between heatwaves and urinary-related hospital admissions was found with a relative risk of 1.090 (95 % confidence interval (CI): 1.050, 1.132). The pooled AF was 8.27 % (95%CI: 4.77 %, 11.63 %), indicating that heatwaves during the warm season (May to September) caused 248,364 urinary-related hospital admissions per year, with 2.42 (95%CI: 1.35, 3.45) billion CNY in economic losses, including 2.23 (95%CI: 1.29, 3.14) billion in direct losses and 0.19 (95%CI, 0.06, 0.31) billion in indirect losses, males, people aged 15-64 years, residents of temperate continental climate zones, and patients with urolithiasis were at higher risk. CONCLUSION: Tailored community health campaigns should be developed and implemented to reduce the adverse health effects and economic losses of heatwave-related urinary diseases, especially in the context of climate change.

Knowledge, Attitude, Risk Perception, and Health-Related Adaptive Behavior of Primary School Children towards Climate Change: A Cross-Sectional Study in China.

BACKGROUND: Children are disproportionately affected by climate change while evidence regarding their adaptive behavior and relevant influencing factors is limited. OBJECTIVES: We attempted to investigate health-related adaptive behavior towards climate change for primary school children in China and explore potential influencing factors. METHODS: We conducted a survey of 8322 primary school children in 12 cities across China. Knowledge, attitude, risk perception, and adaptive behavior scores for children were collected using a designed questionnaire. Weather exposures of cities were collected from 2014 to 2018. We applied a multiple linear regression and mixed-effect regression to assess the influencing factors of adaptive behavior. We also used the structural equation model (SEM) to validate the theoretical framework of adaptive behavior. RESULTS: Most children (76.1%) were aware of climate change. They mainly get information from television, smartphones, and the Internet. A 1 score increase in knowledge, attitude, and risk perception was associated with 0.210, 0.386, and 0.160 increase in adaptive behavior scores, respectively. Females and children having air conditioners or heating systems at home were positively associated with adaptive behavior. Exposure to cold and rainstorms increased the adaptive behavior scores, while heat exposure had the opposite effects. The SEM showed that knowledge was positively associated with attitude and risk perception. Knowledge, attitude, and risk perception corresponded to 31.6%, 22.8%, and 26.1% changes of adaptive behavior, respectively. CONCLUSION: Most primary school children in China were aware of climate change. Knowledge, attitude, risk perception, cold, and rainstorm exposure were positively associated with health-related adaptive behavior towards climate change.

Association of indoor noise level with depression in hotel workers: A multicenter study from 111 China's cities.

Several studies have elucidated the link between outdoor noise and depression, but the relationship between indoor noise levels and depression symptoms in residential and public places remains unclear. This study was a multicenter observational study with a cross-sectional design. In 2019, a total of 10 545 indoor noise levels on-site and 26 018 health data from practitioners were collected from 2402 hotels in 111 cities. Indoor daily noise data levels were detected, and PHQ-9 questionnaires were used to collect health data. Logistic analysis was used to determine the association between depression score and noise level, negative binomial regression was used to determine potential risks. The geometric mean indoor noise level was 38.9 dB (A), with approximately 40.9% of hotels exceeding the 45 dB value (A). Approximately 19.1% of hotel workers exhibited mild and above depressive symptoms. In addition to functional zoning, geographic location, central air conditioner, decoration status, and other factors had an impact on noise levels (p < 0.05). Results of logistic and negative binomial regression showed the following: (1) there was significantly positive association between indoor noise and high depression scores above 2 (OR = 1.007, 95% CI: 1.002, 1.012) and (2) some sub-groups were more susceptible to this effect, especially for the younger female workers working in the first-tier cities, having higher education level, lower level of income, smoking, and longer working hours. This study confirms an early potential effect of indoor noise on depression. It is recommended to implement evidence-based measures to control noise sources in hotels.

Heat and outpatient visits of skin diseases - A multisite analysis in China, 2014-2018.

Background: Many studies have shown that various kinds of diseases were associated with the variation of ambient temperature. However, there's only a scrap of evidence paying attention to the link between temperature and skin diseases, and no relevant national research was performed in China. Objective: This study aimed to quantify the effect of heat on skin diseases and identify the vulnerable populations and areas in China. Methods: Daily meteorological data, air pollutant data and outpatient data were collected from in 18 sites of China during 2014-2018. A time-series study with distributed lag nonlinear model and multivariate meta-analysis was applied to analyze the site-specific and pooled associations between daily mean temperature and daily outpatient visits of skin diseases by using the data of warm season (from June to September). Stratified analysis by age, sex and climate zones and subtypes of skin diseases were also conducted. Results: We found a positive linear relationship between the ambient temperature and risk of skin diseases, with a 1.25% (95%CI: 0.34%, 2.16%) increase of risk of outpatient visits for each 1 °C increase in daily mean temperature during the warm season. In general, groups aged 18-44 years, males and people living in temperate climate regions were more susceptible to high temperature. Immune dysfunction including dermatitis and eczema were heat-sensitive skin diseases. Conclusions: Our findings suggested that people should take notice of heat-related skin diseases and also provided some references about related health burden for strategy-makers. Targeted measures for vulnerable populations need to be taken to reduce disease burden, including monitoring and early warning systems, and sun-protection measures.

Temperature and influenza transmission: Risk assessment and attributable burden estimation among 30 cities in China.

BACKGROUND: Many studies have explored the epidemiological characteristics of influenza. However, most previous studies were conducted in a specific region without a national picture which is important to develop targeted strategies and measures on influenza control and prevention. OBJECTIVES: To explore the association between ambient temperature and incidence of influenza, to estimate the attributable risk from temperature in 30 Chinese cities with different climatic characteristics for a national picture, and to identify the vulnerable populations for national preventative policy development. METHODS: Daily meteorological and influenza incidence data from the 30 Chinese cities over the period 2016-19 were collected. We estimated the city-specific association between daily mean temperature and influenza incidence using a distributed lag non-linear model and evaluated the pooled effects using multivariate meta-analysis. The attributable fractions compared with reference temperature were calculated. Stratified analyses were performed by region, sex and age. RESULTS: Overall, an N-shape relationship between temperature and influenza incidence was found in China. The cumulative relative risk of the peak risk temperature (5.1 °C) was 2.13 (95%CI: 1.41, 3.22). And 60% (95%eCI: 54.3%, 64.3%) of influenza incidence was attributed to ambient temperature during the days with sensitive temperatures (1.6°C-14.4 °C). The ranges of sensitive temperatures and the attributable disease burden due to temperatures varied for different populations and regions. The residents in South China and the children aged ≤5 and 6-17 years had higher fractions attributable to sensitive temperatures. CONCLUSIONS: Tailored preventions targeting on most vulnerable populations and regions should be developed to reduce influenza burden from sensitive temperatures.

The relationship of residential formaldehyde pollution in 11 Chinese cities to schoolchildren pneumonia prevalence in actual living condition.

Residential formaldehyde pollution is one of the leading residential harmful pollutants with a large production and consumption globally and remains much uncertainty in Chinese families with huge health burden for children worldwide. A multi-center observation study from 11 cities was conducted to investigate residential formaldehyde pollution levels measured by phenol reagent spectrophotometry. Data on household characteristics and schoolchildren's health were collected by questionnaire. The median concentration of residential formaldehyde was 0.025 (0.002-0.281) mg/m3 among 11 cities with the total exceeding standard rate of 7.40% according to the reference value of 0.10 mg/m3 (1-h average). Residential formaldehyde pollution in warm season, bedrooms and northern cities was more serious than that in cold season, living rooms and southern cities, respectively. The potential influencing factors of residential formaldehyde included household characteristics (distance from a traffic road, building history, residence duration, window glass layers, decoration and furniture) and use of air conditioner. The positive regulation effect of temperature on residential formaldehyde was explored with the approximately turning-point temperature of 28.9 °C for peak concentration. Long-term exposure to residential formaldehyde of low concentrations (0.010-0.090 mg/m3) would increase the prevalence of childhood pneumonia and a more stringent criteria value for residential formaldehyde should be discussed cautiously.

Independent and Interactive Effects of Environmental Conditions on Aerosolized Surrogate SARS-CoV-2 - Beijing, China, June to September 2020.

What is already known about this topic?: Environmental factors such as temperature and humidity play important roles in the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via droplets/aerosols. What is added by this report?: Higher relative humidity (61%-80%), longer spreading time (120 min), and greater dispersal distance (1 m) significantly reduced SARS-CoV-2 pseudovirus loads. There was an interaction effect between relative humidity and spreading time. What are the implications for public health practice?: The findings contribute to our understanding of the impact of environmental factors on the transmission of SARS-CoV-2 via airborne droplets/aerosols.

Seasonal variation in association between temperature change and emergency department visits: A multi-site study in China.

BACKGROUND: There is limited evidence of effects and seasonal variation of temperature change on emergency department visits (EDVs). OBJECTIVE: To investigate the association between diurnal temperature range (DTR), temperature change between neighboring days (TCN) and a comprehensive collection of cause-specific EDVs in China. METHODS: We collected EDVs, weather, and air pollution data in 20 sites in China from 2014 to 2018. We applied a quasi-Poisson regression with distributed lag nonlinear model to evaluate DTR- and TCN-EDVs association. We used meta-analysis to pool site-specific estimates. We also conducted seasonal analysis and assess effects of modifiers. RESULTS: A 1 °C increase of DTR and TCN was associated with 0.29% [95% confidence interval (CI): 0.07%, 0.51%)] and 1.44% (95% CI: 0.93%, 1.96%) increase of total EDVs, respectively. People aged 18-44 were sensitive to DTR and TCN, while the elderly population was sensitive to TCN only in spring and autumn. In seasonal analysis, effects of temperature change on total EDVs were lower in summer. TCN increased risks of genitourinary diseases in summer, respiratory diseases in winter, injury in autumn, and mental diseases in spring. DTR increased the risk of respiratory diseases in autumn. CONCLUSION: Exposure to DTR and TCN was associated with elevated risk of EDVs but with great seasonal variations. Our results provided potential time and target populations for adaptive strategies and preventive measures.

Effects of Cold Spells on Mortality - Ningbo City, Zhejiang Province, China, 2014-2018.

What is already known about this topic?: In recent years, climate change may lead to an increase in cold spells in the middle latitudes, and there is a positive correlation between cold spells and population mortality. What is added by this report?: The acute response period and the vulnerable population were identified under the optimal definition of cold spells, and the mortality burden caused by cold spells was estimated. What are the implications for public health practice?: This research would provide evidence on the acute mortality effects of cold spells in southern China. Therefore, vulnerable populations, especially the elderly, should take timely measures to reduce the health damage caused by cold spells, especially in the first week after cold waves.

Levels, distributions and influential factors of residential airborne culturable bacteria in 12 Chinese cities: Multicenter on-site survey among dwellings.

Residential airborne culturable bacteria (RAB) are commonly used to assess indoor microbial loads, which is a very effective and recognized indicator of public concern about residential air quality. Many countries and organizations have set exposure limits for residential bacteria. Nevertheless, few studies have been conducted in multicenter cities about the distribution and influencing factors of RAB. It is a challenge to investigate the distribution of RAB and identify the association between indoor influencing variables and RAB in China. The current finding implied the comparative results from a one-year on-site survey of 12 cities in China. The concentration of RAB ranged from 0 CFU/m3 to 18,078 CFU/m3, with an arithmetic median of 350 CFU/m3. RAB concentrations were more in the warm season than those in the cold season, and were more in the bedrooms than those in the living rooms. Indoor environmental indicators (including PM2.5 and PM10) showed the mediating role in the process of temperature and relative humidity effects on RAB. . Influential factors including family-related information (income), architectural characteristics (house type, building history, living floor, the layers of window glass, and decoration) and lifestyle behaviors (heating, new furniture, incense-burned, insecticides-used, air condition-used, and plants-growed) were related with the concentration of RAB. This study presents essential data on the distribution of RAB in some Chinese cities, and reveals the residential influential factors that might minimize health risk from RAB.

Effectiveness Evaluation of a Primary School-Based Intervention against Heatwaves in China.

BACKGROUND: Evidence of the effectiveness of intervention against extreme heat remains unclear, especially among children, one of the vulnerable populations. This study aimed to evaluate the effectiveness of a primary school-based intervention program against heatwave and climate change in China to provide evidence for development of policies for adaptation to climate change. METHODS: Two primary schools in Dongtai City, Jiangsu Province, China, were randomly selected as intervention and control schools (CTR registration number: ChiCTR2200056005). Health education was conducted at the intervention school to raise students' awareness and capability to respond to extreme heat during May to September in 2017. Knowledge, attitude, and practice (KAP) of students and their parents at both schools were investigated by questionnaire surveys before and after intervention. The changes in KAP scores after intervention were evaluated using multivariable difference-in-difference (DID) analysis, controlling for age, sex, etc. Results: The scores of knowledge, attitude, and practice of students and their parents increased by 19.9% (95%CI: 16.3%, 23.6%) and 22.5% (95%CI: 17.8%, 27.1%); 9.60% (95%CI: 5.35%, 13.9%) and 7.22% (95%CI: 0.96%, 13.5%); and 9.94% (95%CI: 8.26%, 18.3%) and 5.22% (95%CI: 0.73%, 9.71%), respectively, after intervention. The KAP score changes of boys were slightly higher than those of girls. Older students had higher score changes than younger students. For parents, the higher the education level, the greater the score change, and change in scores was greater in females than in males. All the health education activities in the program were significantly correlated with the changes in KAP scores of primary school students after intervention, especially those curricula with interesting activities and experiential learning approaches. CONCLUSIONS: Heat and health education program in primary school was an effective approach to improve cognition and behavior for both students and their parents to better adapt to heatwaves and climate change. The successful experience can be generalized to respond to the increasing extreme weather/climate events in the context of climate change, such as heatwaves, and other emergent occasions or public health education, such as the control and prevention of COVID-19.

PKG II secreted via the classical endoplasmic reticulum-Golgi apparatus secretory pathway blocks the activation of EGFR through phosporalting its threonine 406 and has an anti-tumor effect.

BACKGROUND: Protein kinase G type II (PKG II) is a serine/threonine-protein kinase that was originally isolated from the small intestinal mucosa with primary functions in the secretion of small intestinal mucosal cells, secretion of renin and aldosterone, and chondrocyte activities. Recent studies have shown that PKG II exerts anti-tumor effects, while a previous study by our group confirmed that PKG II inhibited the proliferation and migration of cancer cells. Interestingly, PKG II, which was typically bound to the intracellular side of the membrane, was detected in the serum and cell culture medium as a diagnostic biomarker of tumor growth. Thus, the aim of the present study was to elucidate the function and the targets of PKG II, and the mechanism underlying the secretion of this kinase. METHODS: Construction of peptides and plasmids, RNA interference, Immunoelectron microscopy, Co-immunoprecipitation, N-glycosylation assay and Isolation of the Golgi apparatus were applied to investigate the secretory mechanism, and the targets and function of PKG II. RESULTS: PKG II was secreted by enterochromaffin (EC) cells, which were components of the endocrine system in the gastrointestinal tract. Myristoylation of glycine 2 and the N-terminal sequence, especially the amino acids 3-30, acted as a signal peptide to induce the secretion of PKG II via the conventional protein secretory pathway. Moreover, recombinant PKG II inhibited the epidermal growth factor (EGF)-induced activation of the EGF receptor via phosphorylating the T406 of the extracellular domain and blocked EGF-triggered proliferation of various cancer cells. CONCLUSIONS: These results revealed a correlation between the endocrine system and the secretion of protein kinase, suggesting a novel protein secretory pathway. The resuls also indicated that secreted PKG II was a potential diagnostic biomarker and an inhibitor of tumor.

Characteristics, distribution, and children exposure assessment of 13 metals in household dust in China: A big data pilot study.

To explore the pollution characteristics of metals in household dust in China and their exposure to children, this study searched peer-reviewed papers published during 1980-2020 and analyzed 30 eligible papers screened under the per-decided strategy. We evaluated the sample-weighted concentration (SWC) of each metal, explored the sources of metals, and presented the quantitative description of spatial-temporary characteristics and children exposure to 13 metals with multi-route under a general living scenario. The results showed the concentrations of 13 metals with a range of 0.89-29 090.19 mg/kg. The SWC of Cd in household dust from rural areas was 3.29 times of that from urban areas, while the SWC of Ni from urban areas was 3.71 times of that from rural areas. The results showed that four principal components were extracted, and the cumulative contribution rate reached 79.127%. The exposure dose of 13 metals to children aged 2-3 years was presented with the highest by ingestion. Metals such as Fe, Zn, and Mn posed inevitable health risk to children with high exposure. Countermeasures should be carried out to minimize the children exposure to metals in household dust urgently, such as the establishment of environmental health standard for household dust.

Declines in Blood Lead Levels Among General Population - China, 2000-2018.

What is already known about this topic?: Environmental and occupational lead exposure has generally declined in the past two decades. However, there is no large-scale monitoring of blood lead levels (BLLs) in the Chinese general population. What is added by this report?: This nationally representative study showed declines of BLLs in all ages of participants; for children aged 3-5 years, down from 78.1 µg/L to 16.9 µg/L, corresponding to 78.4% decrease in the past two decades (2000-2018). What are the implications for public health practice?: Recommendations for elevated BLLs on screening children at high risk now need to be revisited and updated from 100 µg/L to 50 µg/L in guidelines to conform with the substantial declines in China.

Assessment of Regional Health Vulnerability to Extreme Heat - China, 2019.

What is already known on this topic? The health risk caused by high-temperatures depends on the interaction between high temperature exposure and the sensitivity and adaptability of the affected populations. What is added by this report? A comprehensive assessment model was established by principal component analysis using the data of 19 cities, 15 provincial-level administrative divisions and used to identify regional characteristics and major influencing factors of health vulnerability to extreme heat in China. What are the implications for public health practice? The results of the health vulnerability assessment could effectively identify the regions highly vulnerable to extreme heat in China and provide scientific evidence for the development of adaptive measures and resource allocation plans.

Indoor air quality in the primary school of China-results from CIEHS 2018 study.

Indoor air quality ((IAQ) in classrooms was associated with the daily exposure of school-age children who are particularly vulnerable to air pollutants exposure, while few data exist to evaluate classroom indoor air quality nationwide in China. The subsample of the CIEHS 2018 study was performed in 66 classrooms of 22 primary schools nationwide in China. Temperature, relative humidity, PM2.5, PM10, CO2, CO, formaldehyde concentrations, bacteria and fungi were detected in all classrooms by using the instruments that meet the specified accuracy. The ratios of indoor to outdoor (I/O) of PM2.5 were calculated in each classroom to identify whether the indoor environment the pollutants comes from outdoors. The indoor PM2.5, PM10, CO, HCHO, bacteria and fungi GM concentration are 47.40 µg/m3, 72.91 µg/m3, 0.37 mg/m3, 0.02 mg/m3, 347.51 CFU/m3 and 362.76 CFU/m3, respectively. We observed that there were 66.5%, 52.6%, 22.4%, 1.8%, and 9.6% of the classrooms that exceeded the guideline values of PM2.5, PM10, CO2, HCHO, and bacteria, respectively. It should be attention that all of the classroom's PM2.5 concentrations in Shijiazhuang and Nanning, PM10 concentrations in Nanning, CO2 concentration in Lanzhou were exceeded the suggested values. Bacteria contamination in Shijiazhuang's classrooms is also serious. All classroom CO concentrations meet the requirement. The results indicated that classroom indoor PM2.5 was significantly positively correlated with indoor PM10 and CO2, while was negative correlated with temperature, CO, and fungi. Our results suggest that indoor air pollution in classrooms was a severe problem in Chinese primary schools. It is necessary to strengthen ventilation in the classroom to improve indoor air quality. What's more, a healthy learning environment should be created for primary school students.

The mortality burden of nervous system diseases attributed to ambient temperature: A multi-city study in China.

BACKGROUNDS: Studies on the association between ambient temperature and human mortality have been widely reported, focusing on common diseases such as cardiopulmonary diseases. However, multi-city studies on the association between both high and low temperatures and mortality of nervous system diseases were scarce, especially on the evidence of vulnerable populations. METHODS: Weekly meteorological data, air pollution data and mortality data of nervous system were collected in 5 cities in China. A quasi-Poisson regression with distributed lag non-linear model (DLNM) was applied to quantify the association between extreme temperatures and mortality of nervous system diseases. Multivariate meta-analysis was applied to estimate the pooled effects at the overall levels. The attributable fractions (AFs) were calculated to assess the mortality burden attributable to both high and low temperatures. Stratified analyses were also performed by gender and age-groups through the above steps. RESULTS: A total of 12,132 deaths of nervous system diseases were collected in our study. The overall minimum mortality temperature was 23.9 °C (61.9th), the cumulative relative risks of extreme heat and cold for nervous system diseases were 1.33(95%CI: 1.10, 1.61) and 1.47(95%CI: 1.27, 1.71). The mortality burden attributed to non-optimal temperatures accounted for 29.54% (95%eCI: 13.45%, 40.52%), of which the mortality burden caused by low temperature and high temperature accounted for 25.89% (95%eCI: 13.03%, 34.36%) and 3.65% (95%eCI: 0.42%, 6.17%), respectively. The mortality burden attributable to ambient temperature was higher in both males and the elderly (>74 years old), with the AF of 31.85% (95%eCI: 20.68%, 39.88%) and 31.14% (95%eCI: -6.83%, 49.51%), respectively. CONCLUSIONS: The non-optimal temperature can increase the mortality of nervous system diseases and the males and the elderly over 74 years have the highest attributable burden. The findings add the evidence of vulnerable populations of nervous system diseases against ambient temperatures.