Rice is a known bioaccumulator of methylmercury (MeHg). Rice consumption may be the primary pathway of MeHg exposure in certain mercury (Hg)-contaminated areas of the world. Pakistan is the 4th-largest rice exporter in the world after India, Thailand, and Vietnam. This study aimed to evaluate the Hg contamination status of rice from Pakistan and the health risks associated with Hg exposure through its consumption. 500 rice grain samples were collected from two major rice-growing provinces, Punjab and Sindh, which contain 92% of Pakistan’s rice cultivation area. Analysis of polished rice showed mean total Hg (THg) concentration of 4.51 ng.g⁻¹, while MeHg concentrations of selected samples averaged 3.71 ng.g⁻¹. Only 2% of the samples exceeded the permissible limit of 20 ng.g⁻¹. Samples collected from Punjab showed higher Hg contents than those from Sindh, possibly due to higher rates of urbanization and industrialization. Rice samples collected from areas near brick-making kilns had the highest Hg concentrations due to emissions from the low-quality coal burned. THg and MeHg contents varied by up to five and fourfold, respectively, between point and non-point Hg pollution sites. Moreover, the %Hg as MeHg in rice did not differ significantly between point and non-point Hg sources. Health risk was assessed by calculating a mean probable daily intake, revealing that Hg intake through rice consumption is within the safe limits recommended by the World Health Organization. However, rice intake may be a substantive pathway of MeHg exposure because fish, which are another major source of Hg, are consumed in Pakistan at some of the world’s lowest rates. This study provides fundamental data for further understanding of the global issue of Hg contamination of rice and its related health risks. Furthermore, the current study suggests there is a need to conduct further research in rice-growing areas at the regional level.

On December 31, 2019, the Chinese authorities reported to the World Health Organization (WHO) the outbreak of a new strain of coronavirus that causes a serious disease in the city of Wuhan, China. This outbreak was classified as SARS-CoV2 and is the cause of the COVID-19 disease. On March 11, 2020, the WHO declares it a Pandemic and today it is considered the greatest challenge in global health that humanity has faced since World War II and it is estimated that between 40 and 60% of the population worldwide will catch the virus. This has caused enormous challenges in countries around the world in social, economic, environmental and obviously health issues. These challenges are mainly due to the effects of the established quarantines in almost all capitals and major cities around the world, from Asia, Europe to America. However, these lockdown which began worldwide from January 23, have had a significant impact on the environment and on the air quality of cities as recently reported by NASA (National Aeronautics and Space Administration) and ESA (European Space Agency), with reductions according to them of up to 30% in some of the epicenters such as the case of Wuhan. Knowing that air pollution causes approximately 29% of lung cancer deaths, 43% of COPD deaths, and 25% of ischemic heart disease deaths, it is important to know the effects of quarantines in cities regarding air quality to take measures that favor populations and urban ecosystems when the emergency ends. Therefore, this paper describes the behavior of PM₂.₅ emissions particulate matter from the 50 most polluted capital cities in the world according to the WHO, measured before-after the start of the quarantine. Likewise, the impact at the local and global level of this emissions behavior, which averaged 12% of PM₂.₅ decrease in these cities.

This study presents the distribution characteristics and possible sources of fine particulate matter (PM₂.₅) and its components, as well as policy-related pollution reduction in the Chinese cities of Jinan, Shijiazhuang (SJZ), Chengdu, Wuxi, Wuhan, and Harbin (HRB). PM₂.₅ samples were collected using mid-volume samplers during the autumn of 2017 in all six cities. The samples were analyzed to determine the ambient PM₂.₅ compositions, including the concentrations of water-soluble inorganic ions (WSIIs), carbonaceous aerosols, and elements concentrations. The chemical ratios of organic carbon to elemental carbon and nitrate to sulfate as well as the enrichment factors of elements were calculated to establish the possible sources of PM₂.₅ in all six cities. The highest PM₂.₅ concentration was 152 μg/m³ in SJZ, while the lowest concentration was 47 μg/m³ in HRB. During the sampling period in these six cities, the PM₂.₅ concentrations exceeded the World Health Organization recommended daily average air quality guidelines by 2.4–6.1 times, and WSIIs, carbonaceous aerosols, and elements accounted for 31.8%–61.6%, 9.8%–35.1%, and 0.9%–2.5% of the PM₂.₅, respectively. In 2013, the Chinese government formulated the Air Pollution Prevention and Control Action Plan (APPCAP) for controlling air pollution, and effective measures have been implemented since then. Compared with previous studies conducted during 2009–2013 before the implementation of the APPCAP, the concentrations of PM₂.₅ and most of its components decreased to varying degrees, and large changes in the chemical ratios of PM₂.₅ components were observed. These results indicate that PM₂.₅ sources vary among these six cities and that China has improved the ambient air quality in these cities through the implementation of air pollution control policies. The APPCAP have achieved considerable results in continuously reducing pollution concentrations, although the air pollution concentrations observed in this study remain high compared with those of other countries.

Heavy metals have been found in increasing concentrations in the aquatic environment. Fishes exposed to such metals have altered gene expression, serum profiles, tissue histology and bioindices that serve as overall health biomarkers. The heavy metals (Ni, Cd, and Cr) accumulated in water and fish tissues, were beyond the permissible limits defined by the Central Pollution Control Board/World Health Organization. Metallothionein (MT) and glutathione peroxidase (GPX) genes expression patterns highlighted the metal-specific exposure of fish. An increased fold change of genes against beta-actin serves as a potential feature for toxicity. Metal toxicity is also reflected by an increased level of digestive enzymes (amylase and lipase) in the serum and alterations in values of reproductive hormones (11-Ketotestosterone and progesterone). Total serum bilirubin attribute to the liver and biliary tract disease in fishes. Histopathological studies show cellular degeneration, breakage, vacuolization signifying the chronic stress.

The emergence of a novel coronavirus named SARS-CoV-2 during December 2019, has caused the global outbreak of coronavirus disease 2019 (COVID-19), which is officially announced to be a pandemic by the World Health Organization (WHO). The increasing burden from this pandemic is seriously affecting everyone’s life, and threating the global public health. Understanding the transmission, survival, and evolution of the virus in the environment will assist in the prevention, control, treatment, and eradication of its infection. Herein, we aimed to elucidate the environmental impacts on the transmission and evolution of SARS-CoV-2, based on briefly introducing this respiratory virus. Future research objectives for the prevention and control of these contagious viruses and their related diseases are highlighted from the perspective of environmental science. This review should be of great help to prevent and control the epidemics caused by emerging respiratory coronaviruses (CoVs).

Little is known about fine particulate matter (PM2.5) exposure among pregnant women in rural China. This study aims to characterize exposure to PM2.5 among pregnant women in rural China, and investigate potential risk factors of personal exposure to PM2.5. The data were obtained from a birth cohort study that enrolled 606 pregnant women in Xuanwei, a county known for its high rates of lung cancer. The personal exposure to PM2.5 was measured using small portable particulate monitors during each trimester of pregnancy. Participants were interviewed using structured questionnaires that sought information on risk factors of PM2.5 exposure. The daily exposure to PM2.5 among the pregnant women ranged from 19.68 to 97.08 μg/m3 (median = 26.08). Exposure to PM2.5 was higher in winter and autumn than other seasons (p < 0.05); higher during the day than during the night (p < 0.001); and greater during cooking hours than during the rest of the day (p < 0.001). Using a mixed effects model, domestic solid fuel for cooking (β = 1.75, p < 0.001), winter and autumn (β = 2.96, p < 0.001), cooking ≥ once per day (β = 1.58, p < 0.05), heating with coal (β = 1.69, p < 0.001), secondhand smoke exposure (β = 1.59, p < 0.001) and township 1(β = 2.39, p < 0.001) were identified as risk factors for personal exposure to PM2.5 of pregnant women throughout pregnancy. Indirect effects of season and township factors on personal PM2.5 exposure were mediated by heating, cooking and domestic fuel using. In conclusion, PM2.5 levels in Xuanwei exceeded WHO guidelines. Seasonal and township factors and individual behaviors like domestic solid fuel using for cooking, heating with coal and secondhand smoke exposure are associated with higher personal PM2.5 exposure among pregnant women in rural China.

Gestational diabetes mellitus (GDM) is associated with adverse short- and long-term health outcomes among mothers and their offspring. GDM affects 0.6%–15% of pregnancies worldwide and its incidence is increasing. However, intervention strategies are lacking for GDM. Previous studies indicated a protective association between greenspace and type 2 diabetes mellitus (T2DM), while few studies have explored the association between greenness and GDM. This study aimed to investigate the association between residential greenness and GDM among women from 40 clinical centers in Guangdong province, south China. The study population comprised 5237 pregnant mothers of fetuses and infants without birth defects, from 2004 to 2016. There were n = 157 diagnosed with GDM according to World Health Organization criteria. We estimated residential greenness using the Normalized Difference Vegetation Index (NDVI), derived from satellite imagery using a spatial-statistical model. Associations between greenness during pregnancy and GDM were assessed by confounder-adjusted random effects log-binomial regression models, with participating centers as the random effect. One interquartile increments of NDVI₂₅₀ₘ, NDVI₅₀₀ₘ and NDVI₁₀₀₀ₘ were associated with 13% (RR = 0.87, 95%CI: 0.87–0.87), 8% (RR = 0.92, 95%CI: 0.91–0.92) and 3% (RR = 0.97, 95%CI: 0.97–0.97) lower risks for GDM, respectively. However, NDVI₃₀₀₀ₘ was not significantly associated with GDM (RR = 0.96, 95%CI: 0.78–1.19). The risk for GDM decreased monotonically with greater NDVI. The protective effect of greenness on GDM was stronger among women with lower socioeconomic status and in environments with a lower level air pollutants. Our results suggest that greenness might provide an effective intervention to decrease GDM. Greenness and residential proximity to greenspace should be considered in community planning to improve maternal health outcomes.

Due to the increase of the human population and the rapid industrial growth in the past few decades, air quality monitoring is essential to assess the pollutant levels of an area. However, monitoring air quality in a high-density area like Sunway City, Selangor, Malaysia is challenging due to the limitation of the local monitoring network. To establish a comprehensive data for air pollution in Sunway City, a mobile monitoring campaign was employed around the city area with a duration of approximately 6 months, from September 2018 to March 2019. Measurements of air pollutants such as carbon dioxide (CO₂) and nitrogen dioxide (NO₂) were performed by using mobile air pollution sensors facilitated with a GPS device. In order to acquire a more in-depth understanding on traffic-related air pollution, the measurement period was divided into two different time blocks, which were morning hours (8 a.m.–12 p.m.) and afternoon hours (3 p.m.–7 p.m.). The data set was analysed by splitting Sunway City into different zones and routes to differentiate the conditions of each region. Meteorological variables such as ambient temperature, relative humidity, and wind speed were studied in line with the pollutant concentrations. The air quality in Sunway City was then compared with various air quality standards such as Malaysian Air Quality Standards and World Health Organisation (WHO) guidelines to understand the risk of exposure to air pollution by the residence in Sunway City.

BACKGROUND: Air pollution is a global problem with PM₂.₅ being one of the major pollutants causing many diseases. The concentrations of PM₂.₅ are found to exceed the World Health Organization (WHO) standards especially in lower middle-income countries (LMICs) that house around 40% of the global population. MATERIALS AND METHODS: Studies conducted globally in the past 5 years (2015–2019) on health effects of PM2.5 were systematically reviewed to understand the current research gaps. For this systematic search, Web of Science and PubMed were used to obtain 247 articles. RESULTS: Systematic review of these studies revealed that PM₂.₅ and other air pollutants have been found to be associated with increased mortality and morbidity due to respiratory, cardiovascular, cerebrovascular disorders and diabetes. However, most of the total studies (~ 69%) were carried out in the high-income countries (HICs) despite the fact that PM₂.₅ concentrations are higher in the LMICs (annual mean exposure (2011–2017) of 48.42 µg/m³) and lower in the HICs (annual mean exposure (2011–2017) of 20.02 µg/m³). Therefore, the exposure response functions for mortality estimates associated with PM₂.₅ and developed using the exposure data from the HICs will not have predictive value in the LMICs. Furthermore, very few studies relate chemical components and source apportionment of PM₂.₅ to the associated toxicity. CONCLUSIONS: More studies on morbidity and mortality associated with PM2.5 and its components are needed in LMICs for better estimation of the overall risks.

Arsenic (As) is a toxic metalloid associated with various negative human health impacts including cancer, skin lesions, cardiovascular diseases, and diabetes. Arsenic contamination of groundwater and soil is a major human health issue, particularly in South and Southeast Asia. Use of As-contaminated groundwater from shallow tube wells for irrigation of paddy rice, the staple food for people in this region, is one of the causes of As-related health impacts. The anaerobic growing conditions of flooded rice paddies and the unique physiology of the rice plants lead to increased As levels in rice. The World Health Organization (WHO) has set advisory levels of As in polished (i.e., white) rice grain at 0.2 mg/kg, but the EU and USA are yet to set legal standards for As in rice and rice-based products. Strategies for lowering As accumulation in rice revolve around two approaches—agronomic and biotechnological. Agronomic approaches, such as mineral supplementation of soil using iron, phosphorus, sulfur, silicon, water management, soil aeration practices, and the use of biological agents, are designed to lower As solubility, and uptake by rice. Rotation of the rice crop with As accumulating plants could also result in lowering soil As. Biotechnological approaches involve producing transgenic rice varieties by altering the expression of genes involved in As uptake, translocation, and sequestration in the plant. These approaches, combined with proper diet management and creating public awareness on potential health risks resulting from chronic exposure to As in rice, could play a key role in risk reduction.