Non-linear association between long-term air pollution exposure and risk of metabolic dysfunction-associated steatotic liver disease

BACKGROUND@#Metabolic Dysfunction-associated Steatotic Liver Disease (MASLD) has become a global epidemic, and air pollution has been identified as a potential risk factor. This study aims to investigate the non-linear relationship between ambient air pollution and MASLD prevalence.@*METHOD@#In this cross-sectional study, participants undergoing health checkups were assessed for three-year average air pollution exposure. MASLD diagnosis required hepatic steatosis with at least 1 out of 5 cardiometabolic criteria. A stepwise approach combining data visualization and regression modeling was used to determine the most appropriate link function between each of the six air pollutants and MASLD. A covariate-adjusted six-pollutant model was constructed accordingly.@*RESULTS@#A total of 131,592 participants were included, with 40.6% met the criteria of MASLD. "Threshold link function," "interaction link function," and "restricted cubic spline (RCS) link functions" best-fitted associations between MASLD and PM2.5, PM10/CO, and O3 /SO2/NO2, respectively. In the six-pollutant model, significant positive associations were observed when pollutant concentrations were over: 34.64 µg/m3 for PM2.5, 57.93 µg/m3 for PM10, 56 µg/m3 for O3, below 643.6 µg/m3 for CO, and within 33 and 48 µg/m3 for NO2. The six-pollutant model using these best-fitted link functions demonstrated superior model fitting compared to exposure-categorized model or linear link function model assuming proportionality of odds.@*CONCLUSION@#Non-linear associations were found between air pollutants and MASLD prevalence. PM2.5, PM10, O3, CO, and NO2 exhibited positive associations with MASLD in specific concentration ranges, highlighting the need to consider non-linear relationships in assessing the impact of air pollution on MASLD.

A comparative assessment of air pollutants of smog in wagah border and other sites in Lahore, Pakistan / Uma avaliação comparativa de poluentes do ar do smog na fronteira de wagah e outros sites em Lahore, Paquistão

Abstract Smog has become the fifth season of Pakistan especially in Lahore city. Increased level of air pollutants (primary and secondary) are thought to be responsible for the formation of smog in Lahore. Therefore, the current study was carried out for the evaluation of air pollutants (primary and secondary) of smog in Wagah border particularly and other sites (Jail road, Gulburg) Lahore. For this purpose, baseline data on winter smog from March to December on primary and secondary air pollutants and meteorological parameters was collected from Environmental Protection Department and Pakistan Meteorological Department respectively. Devices being used in both departments for analysis of parameters were also studied. Collected data was further statistically analyzed to determine the correlation of parameters with meteorological conditions and was subjected to air quality index. According to results, PM 10 and PM 2.5 were found very high above the NEQS. NOx concentrations were also high above the permissible limits whereas SO2 and O3 were found below the NEQS thus have no roles in smog formation. Air Quality Index (AQI) of pollutants was PM 2.5(86-227), PM 10 (46-332), NOx (26-110), O3 (19-84) and SO2 (10-95). AQI of PM 2.5 remained between moderate to very unhealthy levels. AQI of PM 10 remained between good to hazardous levels. AQI of NOx remained between good to unhealthy for sensitive groups' levels. AQI of O3 and SO2 remained between good to moderate levels. Pearson correlation showed that every pollutant has a different relation with different or same parameters in different areas. It is concluded from the present study that particulate matter was much more responsible for smog formation. Although NOx also played role in smog formation. So there is need to reduce sources of particulate matter and NOx specifically in order to reduce smog formation in Lahore.

Resumo Smog tornou-se a quinta estação do Paquistão, especialmente na cidade de Lahore. Acredita-se que o aumento do nível de poluentes atmosféricos (primários e secundários) seja responsável pela formação de poluição atmosférica em Lahore. Portanto, o presente estudo foi realizado para a avaliação dos poluentes atmosféricos (primários e secundários) do smog na fronteira de Wagah em particular e em outros locais (Jail road, Gulburg) Lahore. Para este propósito, os dados de referência sobre a poluição atmosférica de inverno de março a dezembro sobre poluentes atmosféricos primários e secundários e parâmetros meteorológicos foram coletados do Departamento de Proteção Ambiental e do Departamento Meteorológico do Paquistão, respectivamente. Dispositivos sendo usados ​​em ambos os departamentos para análise de parâmetros também foram estudados. Os dados coletados foram posteriormente analisados ​​estatisticamente para determinar a correlação dos parâmetros com as condições meteorológicas e foram submetidos ao índice de qualidade do ar. De acordo com os resultados, PM 10 e PM 2,5 foram encontrados muito acima do NEQS. As concentrações de NOx também estavam muito acima dos limites permitidos, enquanto SO2 e O3 foram encontrados abaixo do NEQS, portanto, não têm papéis na formação de smog. O índice de qualidade do ar (AQI) de poluentes foi PM 2,5 (86-227), PM 10 (46-332), NOx (26-110), O3 (19-84) e SO2 (10-95). O AQI de PM 2,5 permaneceu entre níveis moderados a muito prejudiciais à saúde. O AQI de PM 10 permaneceu entre níveis bons e perigosos. AQI de NOx permaneceu entre bom e não saudável para os níveis de grupos sensíveis. O AQI de O3 e SO2 permaneceu entre níveis bons a moderados. A correlação de Pearson mostrou que cada poluente tem uma relação diferente com parâmetros diferentes ou iguais em áreas diferentes. Conclui-se do presente estudo que o material particulado foi muito mais responsável pela formação de smog. Embora o NOx também tenha desempenhado um papel na formação do smog. Portanto, é necessário reduzir as fontes de partículas e NOx, especificamente para reduzir a formação de smog em Lahore.

Ambient Fine Particulate Matter Exposure and Blood Pressure: Evidence from a Large Chinese Multiple Follow-Up Study / 生物医学与环境科学（英文）

OBJECTIVE@#This study aimed to investigate the association of ambient PM2.5 exposure with blood pressure (BP) at the population level in China.@*METHODS@#A total of 14,080 participants who had at least two valid blood pressure records were selected from the China Health and Retirement Longitudinal Survey during 2011-2015. Their long-term PM2.5 exposure was assessed at the geographical level, on the basis of a regular 0.1° × 0.1° grid over China. A mixed-effects regression model was used to assess associations.@*RESULTS@#Each decrease of 10 μg/m3 in the 1 year-mean PM2.5 concentration (FPM1Y) was associated with a decrease of 1.24 [95% confidence interval (CI): 0.84-1.64] mmHg systolic BP (SBP) and 0.50 (95% CI: 0.25-0.75) mmHg diastolic BP (DBP), respectively. A robust association was observed between the long-term decrease in PM2.5 and decreased BP in the middle-aged and older population. Using a generalized additive mixed model, we further found that SBP increased nonlinearly overall with FPM1Y but in an approximately linear range when the FPM1Y concentration was < 70 µg/m3; In contrast, DBP increased approximately linearly without a clear threshold.@*CONCLUSION@#Efficient control of PM2.5 air pollution may promote vascular health in China. Our study provides robust scientific support for making the related air pollution control policies.

Quantitative risk assessment of occupational exposure to PCDD/Fs in the waste incineration industry / 中华劳动卫生职业病杂志

Objective: To analyze the level of PCDD/Fs exposure of occupational workers in the waste incineration industry and explore the risk of occupational exposure. Methods: In September 2021, literature on environmental PCDD/Fs exposure in waste incineration plants published from the establishment of the database to February 10, 2021 was retrieved from CNKI database. A total of 1365 literatures were retrieved, and 7 met the criteria for inclusion. The US Environmental Protection Agency (EPA) inhalation risk model was used to assess and analyze carcinogenic and non-carcinogenic risks of PCDD/Fs exposure among occupational workers in the waste incineration industry. Results: A total of 86 sampling sites were included in incineration plants in 7 regions. The study of Wuhan area showed that the concentration of working environment near the waste incinerator in the same factory was the highest, followed by the rest and office area in the factory. The concentration of PCDD/Fs in waste incinerators was the highest in Southwest China (4880.00-24880.00 pg TEQ/m(3)), and the lowest in Shenzhen (0.02-0.44 pg TEQ/m(3)). According to the cancer risk assessment, with the increase of exposure years, the risk of cancer increased. The highest risk of cancer was found in the waste incineration plants in Southwest China. When the exposure period was 1 year, the risk was moderate (22.40×10(-6)-114.20×10(-6)). When the exposure time was more than 5 years, the risk of cancer was high. In Jinan, workers working near the incinerator had a moderate risk of cancer after five years of exposure. In Zhejiang, workers were at medium risk of cancer after exposure for more than 20 years. Workers in Wuhan, Shanghai, Zhejiang Province, Shenzhen and the Pearl River Delta were still at low risk of cancer after 40 years of occupational exposure. HQ>1 of workers working near the waste incinerators in Jinan, Zhejiang Province and Southwest China, and the qualitative evaluation results showed that the non-carcinogenic risk was unacceptable. Conclusion: There are great differences in PCDD/Fs of occupational exposure in waste incineration industry, and the occupational exposure exceeding the occupational exposure limit has higher carcinogenic and non carcinogenic risks.

Joint effects of meteorological factors and PM2.5 on age-related macular degeneration: a national cross-sectional study in China

BACKGROUND@#Weather conditions are a possible contributing factor to age-related macular degeneration (AMD), a leading cause of irreversible loss of vision. The present study evaluated the joint effects of meteorological factors and fine particulate matter (PM2.5) on AMD.@*METHODS@#Data was extracted from a national cross-sectional survey conducted across 10 provinces in rural China. A total of 36,081 participants aged 40 and older were recruited. AMD was diagnosed clinically by slit-lamp ophthalmoscopy, fundus photography, and spectral domain optical coherence tomography (OCT). Meteorological data were calculated by European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis and were matched to participants' home addresses by latitude and longitude. Participants' individual PM2.5 exposure concentrations were calculated by a satellite-based model at a 1-km resolution level. Multivariable-adjusted logistic regression models paired with interaction analysis were performed to investigate the joint effects of meteorological factors and PM2.5 on AMD.@*RESULTS@#The prevalence of AMD in the study population was 2.6% (95% CI 2.42-2.76%). The average annual PM2.5 level during the study period was 63.1 ± 15.3 µg/m3. A significant positive association was detected between AMD and PM2.5 level, temperature (T), and relative humidity (RH), in both the independent and the combined effect models. For PM2.5, compared with the lowest quartile, the odds ratios (ORs) with 95% confidence intervals (CIs) across increasing quartiles were 0.828 (0.674,1.018), 1.105 (0.799,1.528), and 2.602 (1.516,4.468). Positive associations were observed between AMD and temperature, with ORs (95% CI) of 1.625 (1.059,2.494), 1.619 (1.026,2.553), and 3.276 (1.841,5.830), across increasing quartiles. In the interaction analysis, the estimated relative excess risk due to interaction (RERI) and the attributable proportion (AP) for combined atmospheric pressure and PM2.5 was 0.864 (0.586,1.141) and 1.180 (0.768,1.592), respectively, indicating a synergistic effect between PM2.5 and atmospheric pressure.@*CONCLUSIONS@#This study is among the first to characterize the coordinated effects of meteorological factors and PM2.5 on AMD. The findings warrant further investigation to elucidate the relationship between ambient environment and AMD.

Early prenatal exposure to air pollutants and congenital heart disease: a nested case-control study

BACKGROUND@#Congenital heart disease (CHD) is one of the most common congenital malformations in humans. Inconsistent results emerged in the existed studies on associations between air pollution and congenital heart disease. The purpose of this study was to evaluate the association of gestational exposure to air pollutants with congenital heart disease, and to explore the critical exposure windows for congenital heart disease.@*METHODS@#The nested case-control study collected birth records and the following health data in Tianjin Women and Children's Health Center, China. All of the cases of congenital heart disease from 2013 to 2015 were selected matching five healthy controls for each case. Inverse distance weighting was used to estimate individual exposure based on daily air pollution data. Furthermore, the conditional logistic regression with distributed lag non-linear model was performed to identify the association between gestational exposure to air pollution and congenital heart disease.@*RESULTS@#A total of 8,748 mother-infant pairs were entered into the analysis, of which 1,458 infants suffered from congenital heart disease. For each 10 µg/m3 increase of gestational exposure to PM2.5, the ORs (95% confidence interval, 95%CI) ranged from 1.008 (1.001-1.016) to 1.013 (1.001-1.024) during the 1st-2nd gestation weeks. Similar weak but increased risks of congenital heart disease were associated with O3 exposure during the 1st week and SO2 exposure during 6th-7th weeks in the first trimester, while no significant findings for other air pollutants.@*CONCLUSIONS@#This study highlighted that gestational exposure to PM2.5, O3, and SO2 had lag effects on congenital heart disease. Our results support potential benefits for pregnancy women to the mitigation of air pollution exposure in the early stage, especially when a critical exposure time window of air pollutants may precede heart development.

Associations between indoor volatile organic compounds and nocturnal heart rate variability of young female adults: A panel study / 北京大学学报(医学版)

OBJECTIVE@#To investigate the association between short-term exposure to indoor total volatile organic compounds (TVOC) and nocturnal heart rate variability (HRV) among young female adults.@*METHODS@#This panel study recruited 50 young females from one university in Beijing, China from December 2021 to April 2022. All the participants underwent two sequential visits. During each visit, real time indoor TVOC concentration was monitored using an indoor air quality detector. The real time levels of indoor temperature, relative humidity, noise, carbon dioxide and fine particulate matter were monitored using a temperature and humidity meter, a noise meter, a carbon dioxide meter and a particulate counter, respectively. HRV parameters were measured using a 12-lead Holter. Mixed-effects models were used to evaluate the association between the TVOC and HRV parameters and establish the exposure-response relationships, and two-pollutant models were applied to examine the robustness of the results.@*RESULTS@#The mean age of the 50 female subjects was (22.5±2.3) years, and the mean body mass index was (20.4±1.9) kg/m2. During this study, the median (interquartile range) of indoor TVOC concentrations was 0.069 (0.046) mg/m3, the median (interquartile range) of indoor temperature, relative humidity, carbon dioxide concentration, noise level and fine particulate matter concentration were 24.3 (2.7) ℃, 38.5% (15.0%), 0.1% (0.1%), 52.7 (5.8) dB(A) and 10.3 (21.5) μg/m3, respectively. Short-term exposure to indoor TVOC was associated with significant changes in time-domain and frequency-domain HRV parameters, and the exposure metric for most HRV parameters with the most significant changes was 1 h-moving average. Along with a 0.01 mg/m3 increment in 1 h-moving average concentration of indoor TVOC, this study observed decreases of 1.89% (95%CI: -2.28%, -1.50%) in standard deviation of all normal to normal intervals (SDNN), 1.92% (95%CI: -2.32%, -1.51%) in standard deviation of average normal to normal intervals (SDANN), 0.64% (95%CI: -1.13%, -0.14%) in percentage of adjacent NN intervals differing by more than 50 ms (pNN50), 3.52% (95%CI: -4.30%, -2.74%) in total power (TP), 5.01% (95%CI: -6.21%, -3.79%) in very low frequency (VLF) power, and 4.36% (95%CI: -5.16%, -3.55%) in low frequency (LF) power. The exposure-response curves showed that indoor TVOC was negatively correlated with SDNN, SDANN, TP, and VLF when the concentration exceeded 0.1 mg/m3. The two-pollutant models indicated that the results were generally robust after controlling indoor noise and fine particulate matter.@*CONCLUSION@#Short-term exposure to indoor TVOC was associated with significant negative changes in nocturnal HRV of young women. This study provides an important scientific basis for relevant prevention and control measures.

Research progress on the relationship between air pollution and gestational diabetes / 中华预防医学杂志

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications and has serious implications for the health of mothers and their offspring. In recent years, studies have confirmed that air pollution is one of the main risk factors for diabetes, and there is increasing evidence that air pollution exposure is closely related to the occurrence of gestational diabetes. However, current studies on the association between air pollutant exposure and the incidence of gestational diabetes are inconsistent, and the window period of pollutant exposure is still unclear. Limited mechanistic studies suggest that airborne particulate matter and gaseous pollutants may affect GDM through multiple mechanisms, including inflammation, oxidative stress, disruption of adipokine secretion, and imbalance of intestinal flora. This review summarizes the relationship between air pollutant exposure and the incidence of GDM in recent years, as well as the possible molecular mechanism of the occurrence and development of GDM caused by air pollutants, in order to provide scientific basis for preventing pollutant exposure, reducing the risk of GDM, improving maternal and fetal outcomes and improving the quality of the birth population.

Revision and prospect of "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. The standards for indoor air quality (GB/T 18883-2022) were issued by the State Administration of Market Regulation and the Standardization Administration on July 11, 2022, and implemented on February 1, 2023 by replacing indoor air quality standards (GB/T 18883-2002). The revised standard specifies hygienic requirements for physical, chemical, biological and radioactive indicators in indoor air and the corresponding test methods. This article interpreted the revision background, drafting principles, main indicators and methods, as well as the revision basis of the standards. Recommendations for the implementation of the standards are also proposed.

Study on formulation and revision of standard limit for formaldehyde in the "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

Formaldehyde, as an important pollutant in indoor air, has always been of great concern. In the newly issued "Standards for indoor air quality (GB/T 18883-2022)", the standard limit of formaldehyde has been restricted to 0.08 mg/m3. In order to better promote the implementation and application of this new standard, this study reviewed and interpreted the relevant technical content for determining the standard limit, including the indoor concentration and human exposure levels of formaldehyde, the health effects of formaldehyde, and the derivation of safety reference values. It also proposed prospect for the future development and revision of quality standards for formaldehyde in indoor air.

Study on revision of standard limits for benzene in"Standards for indoor air quality（GB/T 18883-2022）"in China / 中华预防医学杂志

Benzene, as a major indoor pollutant, has received widespread attention. In order to better control indoor benzene pollution and protect people's health, the limit value of benzene in the"Standards for indoor air quality (GB/T 18883-2022)'' was reduced from 0.11 mg/m3 to 0.03 mg/m3. This study reviewed and discussed the relevant technical contents of the determination of benzene limit value, including the exposure status of benzene, health effects, and derivation of the limit value. It also proposed prospects for the future direction of formulating indoor air benzene standards.

Study on formulation and revision of standard limits for inhalable particulate matter (PM10) and fine particulate matter (PM2.5) in "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

The pollution and health effects of indoor inhalable particulate matter (PM10) and fine particulate matter (PM2.5) are increasingly receiving public attention. The"Standards for indoor air quality (GB/T 18883-2022)"has revised the standard limit for PM10 and added the standard limit for PM2.5. This study analyzed and interpreted the relevant technical contents of the revision of the standard limits for two indicators, including the exposure status, health effects, and the basis for the determination of the limit value. It also proposed prospects for the future development and revision of standard limits for indoor particulate matters.

Study on revision of standard limits for nitrogen dioxide in "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

Nitrogen dioxide (NO2) is an important indoor air pollutant, with both outdoor and indoor sources contributing to indoor NO2 exposure levels. Considering the association of high NO2 exposure with adverse health effects, the Standards for indoor air quality (GB/T 18883-2022) have been revised to further restrict indoor NO2 limit values. The 1-h average concentration limit value for NO2 has been reduced from 0.24 mg/m3 to 200 μg/m3.This study analyzed the technical contents related to the determination of the limits of indoor NO2 in Standards for Indoor Air Quality (GB/T 18883-2022), including source, exposure level, health effects, and the process and evidence basis for determining the limit value. It also proposed prospects for the direction for the implementation of the indoor NO2 standard.

Study on formulation and revision of detection methods of "Standards for indoor air quality (GB/T 18883-2022)" in China / 中华预防医学杂志

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

Revision and prospect of "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. The standards for indoor air quality (GB/T 18883-2022) were issued by the State Administration of Market Regulation and the Standardization Administration on July 11, 2022, and implemented on February 1, 2023 by replacing indoor air quality standards (GB/T 18883-2002). The revised standard specifies hygienic requirements for physical, chemical, biological and radioactive indicators in indoor air and the corresponding test methods. This article interpreted the revision background, drafting principles, main indicators and methods, as well as the revision basis of the standards. Recommendations for the implementation of the standards are also proposed.

Study on formulation and revision of standard limit for formaldehyde in the "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

Formaldehyde, as an important pollutant in indoor air, has always been of great concern. In the newly issued "Standards for indoor air quality (GB/T 18883-2022)", the standard limit of formaldehyde has been restricted to 0.08 mg/m3. In order to better promote the implementation and application of this new standard, this study reviewed and interpreted the relevant technical content for determining the standard limit, including the indoor concentration and human exposure levels of formaldehyde, the health effects of formaldehyde, and the derivation of safety reference values. It also proposed prospect for the future development and revision of quality standards for formaldehyde in indoor air.

Study on revision of standard limits for benzene in"Standards for indoor air quality（GB/T 18883-2022）"in China / 中华预防医学杂志

Benzene, as a major indoor pollutant, has received widespread attention. In order to better control indoor benzene pollution and protect people's health, the limit value of benzene in the"Standards for indoor air quality (GB/T 18883-2022)'' was reduced from 0.11 mg/m3 to 0.03 mg/m3. This study reviewed and discussed the relevant technical contents of the determination of benzene limit value, including the exposure status of benzene, health effects, and derivation of the limit value. It also proposed prospects for the future direction of formulating indoor air benzene standards.

Study on formulation and revision of standard limits for inhalable particulate matter (PM10) and fine particulate matter (PM2.5) in "Standards for indoor air quality（GB/T 18883-2022）" in China / 中华预防医学杂志

The pollution and health effects of indoor inhalable particulate matter (PM10) and fine particulate matter (PM2.5) are increasingly receiving public attention. The"Standards for indoor air quality (GB/T 18883-2022)"has revised the standard limit for PM10 and added the standard limit for PM2.5. This study analyzed and interpreted the relevant technical contents of the revision of the standard limits for two indicators, including the exposure status, health effects, and the basis for the determination of the limit value. It also proposed prospects for the future development and revision of standard limits for indoor particulate matters.