Cross-sectional study protocol to assess the environmental exposure of endocrine disruptive chemicals: bisphenol-A and heavy metals in children.

INTRODUCTION: Endocrine-disruptors are exogenous compounds that interfere with the human biological system. Bisphenol-A and toxic ele-mental mixtures (e.g. As, Pb, Hg, Cd, and U) are major endocrine-disruptive chemicals documented by the USEPA. Globally obesi-ty is a major health problem with increasing fast-food intake among children. The use of food packaging material is rising global-ly, becoming a primary source of chemical migration from food contact materials. MATERIAL AND METHODS: This protocol is a cross-sectional study, and the primary outcome is to assess the various dietary and non-dietary exposure sources of endocrine-disruptive chemicals (bisphenol A and heavy metals) through a questionnaire, and quantification of urinary bisphenol A and heavy metals using LC-MS/MS and ICP-MS, respectively, among children. In this study, anthropometric assess-ment, socio-demographic characteristics, and laboratory investigations will be performed. Exposure pathway assessment will be done using questions about household characteristics, surroundings, food and water sources, physical/dietary habits, and nutri-tional assessment. RESULTS: An exposure pathway model will be developed based on the questions on source, pathway/exposure, and receptor (child), of those exposed to or potentially exposed to the endocrine-disruptive chemicals. CONCLUSIONS: The children who are exposed or potentially exposed to the chemical migration sources need intervention through local bodies, school curriculum, and training programs. Also, methodological points of view implication of regression models and the LASSO approach will be assessed to identify the emerging risk factors of childhood obesity and even reverse causality through multi-pathway exposure sources. The feasibility of the current study outcome can be implicated in developing countries.

PM2.5 mediated alterations in the in vitro human granuloma and its effect on reactivation of mycobacteria.

Exposure to particulate matter pollutant PM2.5 diminishes the immune response to mycobacterial antigens relevant to contain the infection in the granuloma, thus leading to reactivation of latent bacilli. The present study was therefore designed based on the hypothesis that exposure to PM2.5 affects the granuloma formation and reactivation of latent mycobacterial bacilli contained in the granuloma. For the sampling of PM2.5, based on initial standardisations, Teflon filter was selected over the quartz filter. Two different approaches were used to study the effect of PM2.5 on the human PBMC granuloma formed by Mycobacterium bovis BCG at multiplicity of infection (MOI) 0.1. In the first approach, granuloma formed in the presence of PM2.5 was loosely packed and ill-defined with significant downregulation of dormancy-associated mycobacterial genes, upregulation of reactivation-associated rpfB gene along with a significant increase in TNFα level without any change in the bacterial load in terms of CFUs. In the second approach, preformed human PBMC granuloma using M. bovis BCG was treated with PM2.5 that resulted in the disruption of granuloma architecture along with downregulation of not only dormancy-associated genes but also reactivation-associated rpfB gene of mycobacterial bacilli recovered from granuloma. However, there was no significant change in the host cytokine levels. Therefore, it can be inferred that PM2.5 can modulate the granuloma formation in vitro as well as mycobacterial gene expression in the granuloma with a possible role in the reactivation of latent bacilli.

A global observational analysis to understand changes in air quality during exceptionally low anthropogenic emission conditions.

This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015-2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O3 and the total gaseous oxidant (OX = NO2 + O3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015-2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO2 and NOx concentrations and peoples' mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO2 and between 30% and 40% in mean PM2.5 concentrations over 2020 full lockdown compared to the same period in 2015-2019. However, PM2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO2/CO ratio). Some Chinese cities showed similar increases in PM2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of ~70%. The SO2 anomalies were negative for 2020 compared to 2015-2019 (between ~25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to ~40%. The NO2/CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO2 decrease due to the general reduction in mobility (ratio of ~60%). Analysis of the total oxidant (OX = NO2 + O3) showed that primary NO2 emissions at urban locations were greater than the O3 production, whereas at background sites, OX was mostly driven by the regional contributions rather than local NO2 and O3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required.

Consideration for the asymptomatic transmission of COVID-19: Systematic Review and Meta-Analysis

ObjectiveWorldwide countries are experiencing viral load in their population, leading to potential infectivity of asymptomatic COVID-19. Current systematic review and meta-analysis aimed to investigate the role of asymptomatic infection worldwide reported in family-cluster, adults, children, health care workers, and travelers. DesignOnline literature search (PubMed, Google Scholar, medRixv, and BioRixv) was accomplished using standard Boolean operators, studies published till 07th June 2020. SettingStudies were included from case reports, short communication, and retrospective to cover sufficient asymptomatic COVID-19 transmission reported. ParticipantsFamilial-clusters, adults, children, health care workers, and travelers. ResultsWe observed asymptomatic transmission among familial-cluster, adults, children, health care workers, and travelers with a proportion of 32% 37%, 26%, 6%, and 32%, respectively. This study observed an overall proportion of 31% (95%CI: 0.19-0.44) with heterogeneity of I2 (97.28%, p=<0.001) among all asymptomatic populations mentioned in this study. Among children and healthcare workers, this study showed no heterogeneity; to overcome the interpretation from a fixed model, the random effect model was also applied to estimate the average distribution across studies included in the meta-analysis. ConclusionWe found and suggest the rigorous epidemiological history, early isolation, social distancing, and increased quarantine period (at least 28 days) after screening asymptomatic cases as well as their close contacts for chest CT scan even after their negative nucleic acid testing to minimize the spread among the community. This systematic review and meta-analysis support asymptomatic COVID-19 transmission between person to person depending on the variation of virus incubation period among individuals. Children especially, school-going aged <18 years, need to be monitored and prevention strategy, e.g., chest CT and social distancing required to prevent the community transmission of COVID-19 in asymptomatic mode. Strengths and limitations of this studyO_LIExamine the possibility of asymptomatic COVID-19 transmission in the community at different levels. C_LIO_LISupports contact tracing, social distancing, early isolation, and increased quarantine period to minimize the risk of virus spread. C_LIO_LISupports chest CT scan and viral nucleic acid testing to identify the asymptomatic cases in the community. C_LIO_LISupports rigorous epidemiological history with multiple detection methods. C_LIO_LIA higher proportion of asymptomatic incidence was seen, suggests monitoring, and maintaining social distancing. C_LI

Low serum copper and zinc concentrations in North Indian children with overweight and obesity

INTRODUCTION: There are limited data on the alterations of serum copper and zinc, which have been proposed to have associations among children with obesity. MATERIAL AND METHODS: A total of 173 children were enrolled and grouped into overweight/obese (n = 69) and non-obese (n = 104) according to CDC 2000 growth charts. Serum and whole blood zinc and copper concentrations were measured by validated ICP-MS method, and copper/zinc ratios were calculated and correlated to various anthropometric parameters. RESULTS: Mean BMI in obese (24.78 ±3.93) was significantly higher as compared to non-obese (16.44 ±2.34; p < 0.0001, 95% CI: 15.9873-16.8998) children. Mean serum copper levels in obese children (1099.80 ±478.67 µg/l) were significantly lower than for non-obese children (2063.77 ±1006.81 µg/l; p = 0.0001, 95% CI: 1867.9755-2259.5755). Similarly, the mean serum zinc levels in obese children (851.53 ±406.33 µg/l) were also significantly lower as compared to non-obese children (1528.72 ±796.82 µg/l; p = 0.0001, 95% CI: 1373.76-1683.6879). Mean whole blood copper levels were significantly lower in obese (929.56 ±200.15 µg/l) as compared to non-obese (1393.22 ±861.92 µg/l; p = 0.0001, 95% CI: 1225.6023-1560.8481) children. Similarly, the mean whole blood zinc levels in obese (4384.11 ±881.87 µg/l) were also significantly lower as compared to non-obese (5380.14 ±2236.77 µg/l; p = 0.001, 95% CI: 4945.1491-5815.1416) children. CONCLUSIONS: The serum and whole blood concentrations of zinc and copper were found to be significantly lower in children with exogenous obesity as compared to controls. Additional investigations are recommended to see the underlying aspect of these elements in the development of obesity along with their co-morbidities.

Assessment of noise pollution in and around a sensitive zone in North India and its non-auditory impacts.

Noise pollution in hospitals is recognized as a serious health hazard. Considering this, the current study aimed to map the noise pollution levels and to explore the self reported non-auditory effects of noise in a tertiary medical institute. The study was conducted in an 1800-bedded tertiary hospital where 27 sites (outdoor, indoor, road side and residential areas) were monitored for exposure to noise using Sound Level Meter for 24h. A detailed noise survey was also conducted around the sampling sites using a structured questionnaire to understand the opinion of the public regarding the impact of noise on their daily lives. The equivalent sound pressure level (Leq) was found higher than the permissible limits at all the sites both during daytime and night. The maximum equivalent sound pressure level (Lmax) during the day was observed higher (>80dB) at the emergency and around the main entrance of the hospital campus. Almost all the respondents (97%) regarded traffic as the major source of noise. About three-fourths (74%) reported irritation with loud noise whereas 40% of respondents reported headache due to noise. Less than one-third of respondents (29%) reported loss of sleep due to noise and 8% reported hypertension, which could be related to the disturbance caused due to noise. Noise levels in and around the hospital was well above the permissible standards. The recent Global Burden of Disease highlights the increasing risk of non communicable diseases. The non-auditory effects studied in the current work add to the risk factors associated with non communicable diseases. Hence, there is need to address the issue of noise pollution and associated health risks specially for vulnerable population.

Growth behavior studies of bread wheat plant exposed to municipal landfill leachate.

Pot experiments were carried out to study the effect of different dilutions of leachate generated from municipal solid waste (MSW) landfill on bread wheat (Triticum aestivum). Eight treatment groups with different concentrations (0-100%) of leachate were prepared and treatments were given to the plants till they reached complete vegetative phase (45 days). The growth performances of wheat plants were assessed in terms of various parameters such as shoot and root length, dry biomass and chlorophyll content. Plants treated with higher concentrations of leachate (75% and 100%) showed higher growth (2.5 and 6%) and 100% survival rate as compared to control. However, high shoot weight (0.028 and 0.030 gm) and high chlorophyll content (213 and 230%) was reported in 30 and 40% leachate treatment as compared to control. Some symptoms of stress (discoloration of leaf blade, wilting and yellowing of plants) were also observed in plants, which could be related to the presence of high concentration of salts in the leachate. The current study suggests that MSW landfill leachate is rich in nutrients and can be used as fertilizer but before its application, the salinity level and concentration of toxic metals present in leachate should be considered in accordance with the tolerance ability of any plant.