Uncovering global-scale risks from commercial chemicals in air.

Commercial chemicals are used extensively across urban centres worldwide1, posing a potential exposure risk to 4.2 billion people2. Harmful chemicals are often assessed on the basis of their environmental persistence, accumulation in biological organisms and toxic properties, under international and national initiatives such as the Stockholm Convention3. However, existing regulatory frameworks rely largely upon knowledge of the properties of the parent chemicals, with minimal consideration given to the products of their transformation in the atmosphere. This is mainly due to a dearth of experimental data, as identifying transformation products in complex mixtures of airborne chemicals is an immense analytical challenge4. Here we develop a new framework-combining laboratory and field experiments, advanced techniques for screening suspect chemicals, and in silico modelling-to assess the risks of airborne chemicals, while accounting for atmospheric chemical reactions. By applying this framework to organophosphate flame retardants, as representative chemicals of emerging concern5, we find that their transformation products are globally distributed across 18 megacities, representing a previously unrecognized exposure risk for the world's urban populations. More importantly, individual transformation products can be more toxic and up to an order-of-magnitude more persistent than the parent chemicals, such that the overall risks associated with the mixture of transformation products are also higher than those of the parent flame retardants. Together our results highlight the need to consider atmospheric transformations when assessing the risks of commercial chemicals.

Mitigation potential of global ammonia emissions and related health impacts in the trade network.

Ammonia (NH3) emissions, mainly from agricultural sources, generate substantial health damage due to the adverse effects on air quality. NH3 emission reduction strategies are still far from being effective. In particular, a growing trade network in this era of globalization offers untapped emission mitigation potential that has been overlooked. Here we show that about one-fourth of global agricultural NH3 emissions in 2012 are trade-related. Globally they induce 61 thousand PM2.5-related premature mortalities, with 25 thousand deaths associated with crop cultivation and 36 thousand deaths with livestock production. The trade-related health damage network is regionally integrated and can be characterized by three trading communities. Thus, effective cooperation within trade-dependent communities will achieve considerable NH3 emission reductions allowed by technological advancements and trade structure adjustments. Identification of regional communities from network analysis offers a new perspective on addressing NH3 emissions and is also applicable to agricultural greenhouse gas emissions mitigation.

Consumption in the G20 nations causes particulate air pollution resulting in two million premature deaths annually.

Worldwide exposure to ambient PM2.5 causes over 4 million premature deaths annually. As most of these deaths are in developing countries, without internationally coordinated efforts this polarized situation will continue. As yet, however, no studies have quantified nation-to-nation consumer responsibility for global mortality due to both primary and secondary PM2.5 particles. Here we quantify the global footprint of PM2.5-driven premature deaths for the 19 G20 nations in a position to lead such efforts. G20 consumption in 2010 was responsible for 1.983 [95% Confidence Interval: 1.685-2.285] million premature deaths, at an average age of 67, including 78.6 [71.5-84.8] thousand infant deaths, implying that the G20 lifetime consumption of about 28 [24-33] people claims one life. Our results indicate that G20 nations should take responsibility for their footprint rather than focusing solely on transboundary air pollution, as this would expand opportunities for reducing PM2.5-driven premature mortality. Given the infant mortality footprint identified, it would moreover contribute to ensuring infant lives are not unfairly left behind in countries like South Africa, which have a weak relationship with G20 nations.

Mold, Mycotoxins and a Dysregulated Immune System: A Combination of Concern?

Fungi represent one of the most diverse and abundant eukaryotes on earth. The interplay between mold exposure and the host immune system is still not fully elucidated. Literature research focusing on up-to-date publications is providing a heterogenous picture of evidence and opinions regarding the role of mold and mycotoxins in the development of immune diseases. While the induction of allergic immune responses by molds is generally acknowledged, other direct health effects like the toxic mold syndrome are controversially discussed. However, recent observations indicate a particular importance of mold/mycotoxin exposure in individuals with pre-existing dysregulation of the immune system, due to exacerbation of underlying pathophysiology including allergic and non-allergic chronic inflammatory diseases, autoimmune disorders, and even human immunodeficiency virus (HIV) disease progression. In this review, we focus on the impact of mycotoxins regarding their impact on disease progression in pre-existing immune dysregulation. This is complemented by experimental in vivo and in vitro findings to present cellular and molecular modes of action. Furthermore, we discuss hypothetical mechanisms of action, where evidence is missing since much remains to be discovered.

Environment-lockdown, air pollution and related diseases: could we learn something and make it last?

Although the pandemic has caused substantial losses in economic prosperity and human lives, it has also some positive impacts on the environment. Restricted mobility, complete closure, less traffic and industry have led to improved air quality especially in urban settings. Not only is air pollution an important determinant of chronic diseases, such as heart and lung disorders, but it has also been shown that poor air quality increases the risk of COVID-19. In this article, we review some of the findings on changes in air quality during the pandemic, and its potential effects on health. We need to continue to monitor the effects of change in air quality, due to COVID-19 lockdown or other factors, but also keep all our efforts to improve air quality even faster and more persistent, bringing the pollution levels below what WHO recommends are safe to live with.

Critical supply chains for mitigating PM2.5 emission-related mortalities in India.

Air pollution and its health-related effects are a major concern globally, and many people die from air pollution-related diseases each year. This study employed a structural path analysis combined with a health impact inventory database analysis to estimate the number of consumption-based PM2.5 emission-related deaths attributed to India's power supply sector. We identified critical supply chain paths for direct (production) electricity use and indirect (consumption) use. We also considered both domestic and foreign final demand and its effect on PM2.5 emission-related deaths. Several conclusions could be drawn from our results. First, the effect of indirect electricity usage on PM2.5 emission-related deaths is approximately four times larger than that for direct usage. Second, a large percentage of pollution-related deaths can be attributed to India's domestic final demand usage; however, electricity usage in the intermediate and final demand sectors is inextricably linked. Third, foreign final demand sectors from the Middle East, the USA, and China contribute indirectly toward PM2.5 emission-related deaths, specifically in the rice export supply chain. The results show that the Indian government should implement urgent measures to curb electricity use in rice supply chains in order to reduce the number of PM2.5 emission-related deaths.

Multiple air pollutant exposure and lung cancer in Tehran, Iran.

Lung cancer is the most rapidly increasing malignancy worldwide with an estimated 2.1 million cancer cases in the latest, 2018 World Health Organization (WHO) report. The objective of this study was to investigate the association of air pollution and lung cancer, in Tehran, Iran. Residential area information of the latest registered lung cancer cases that were diagnosed between 2014 and 2016 (N = 1,850) were inquired from the population-based cancer registry of Tehran. Long-term average exposure to PM10, SO2, NO, NO2, NOX, benzene, toluene, ethylbenzene, m-xylene, p-xylene, o-xylene (BTEX), and BTEX in 22 districts of Tehran were estimated using land use regression models. Latent profile analysis (LPA) was used to generate multi-pollutant exposure profiles. Negative binomial regression analysis was used to examine the association between air pollutants and lung cancer incidence. The districts with higher concentrations for all pollutants were mostly in downtown and around the railway station. Districts with a higher concentration for NOx (IRR = 1.05, for each 10 unit increase in air pollutant), benzene (IRR = 3.86), toluene (IRR = 1.50), ethylbenzene (IRR = 5.16), p-xylene (IRR = 9.41), o-xylene (IRR = 7.93), m-xylene (IRR = 2.63) and TBTEX (IRR = 1.21) were significantly associated with higher lung cancer incidence. Districts with a higher multiple air-pollution profile were also associated with more lung cancer incidence (IRR = 1.01). Our study shows a positive association between air pollution and lung cancer incidence. This association was stronger for, respectively, p-xylene, o-xylene, ethylbenzene, benzene, m-xylene and toluene.

Unprecedented reduction in air pollution and corresponding short-term premature mortality associated with COVID-19 lockdown in Delhi, India.

Countries around the world introduced strict restrictions on movement and activities known as 'lockdowns' to restrict the spread of the novel coronavirus disease (COVID-19) from the end of 2019. A sudden improvement in air quality was observed globally as a result of these lockdowns. To provide insight into the changes in air pollution levels in response to the COVID-19 restrictions we have compared surface air quality data in Delhi during four phases of lockdown and the first phase of the restriction easing period (25 March to 30 June 2020) with data from a baseline period (2018-2019). Simultaneously, short-term exposure of PM2.5 and O3 attributed premature mortality were calculated to understand the health benefit of the change in air quality. Ground-level observations in Delhi showed that concentrations of PM10, PM2.5 and NO2 dropped substantially in 2020 during the overall study period compared with the same period in previous years, with average reductions of ~49%, ~39%, and ~39%, respectively. An overall lower reduction in O3 of ~19% was observed for Delhi. A slight increase in O3 was found in Delhi's industrial and traffic regions. The highest peak of the diurnal variation decreased substantially for all the pollutants at every phase. The decrease in PM2.5 and O3 concentrations in 2020, prevented 904 total premature deaths, a 60% improvement when compared to the figures for 2018-2019. The restrictions on human activities during the lockdown have reduced anthropogenic emissions and subsequently improved air quality and human health in one of the most polluted cities in the world.Implications: I am submitting herewith the manuscript entitled "Unprecedented Reduction in Air Pollution and Corresponding Short-term Premature Mortality Associated with COVID-19 Forced Confinement in Delhi, India" for potential publishing in your journal.The novelty of this research lies in: (1) we utilized ground-level air quality data in Delhi during four phases of lockdown and the first phase of unlocking period (25th March to 30th June) for 2020 as well as data from the baseline period (2018-2019) to provide an early insight into the changes in air pollution levels in response to the COVID-19 pandemic, (2) Chatarize the change of diurnal variation of the pollutants and (3) we assess the health risk due to PM2.5 and O3. Results from ground-level observations in Delhi showed that concentrations of PM10, PM2.5 and NO2 substantially dropped in 2020 during the overall study period compared to the similar period in previous years, with an average reduction of ~49%, ~39%, and ~39%, respectively. In the case of O3, the overall reduction was observed as ~19% in Delhi, while a slight increase was found in industrial and traffic regions. And consequently, the highest peak of the diurnal variation decreased substantially for all the pollutants. The health impact assessment of the changes in air quality indicated that 904 short-term premature deaths (~60%) were prevented due to the decline in PM2.5 and O3 concentrations in the study period. The restrictions on human activities during the lockdown have reduced the anthropogenic emissions and subsequently improved air quality and human health in one of the most polluted cities in the world.

Fatal poisoning of four workers in a farm: Distribution of hydrogen sulfide and thiosulfate in 10 different biological matrices.

We evaluate the distribution of sulfide and thiosulfate (TS) in biological samples of four dairy farmers died inside a pit connected to a manure lagoon. Autopsies were performed 4 days later. Toxicological analyses of sulfide and TS were made using an extractive alkylation technique combined with gas chromatography/mass spectrometry (GC/MS). Autopsies revealed: multiorgan congestion; pulmonary edema; manure inside distal airways of three of the four victims. Sulfide concentrations were cardiac blood: 0.5-3.0 µg/mL, femoral blood: 0.5-1.2 µg/mL, bile: <0.1-2.2 µg/mL; liver 2.8-8.3 µg/g, lung: 5.0-9.4 µg/g, brain: 2.7-13.9 µg/g, spleen: 3.3-6.3 µg/g, fat: <0.1-1.5 µg/g, muscle: 2.6-3.5 µg/g. TS concentrations were cardiac blood: 2.1-4.9 µg/mL, femoral blood: 2.1-2.3 µg/mL, bile: 2.5-4.4 µg/mL, urine: <0.5-1.8 µg/mL; liver <0.5-2.6, lung: 2.8-5.4 µg/g, brain: <0.5-1.9 µg/g, spleen: 1.2-2.9 µg/g, muscle: <0.5-5.6 µg/g. The cause of death was assessed to be acute poisoning by hydrogen sulfide (H2S) for all the victims. Manure inhalation contributed to the death of three subjects. The measurement of sulfide and TS concentrations in biological samples contributed to better understand the sequence of the events. Subjects 3 provided the highest concentration of sulfide in brain, thus, supporting the hypothesis of a rapid loss of consciousness and respiratory depression. One by one, the other farmers entered the pit in attempts to rescue the coworkers but collapsed. Despite the rapid death, subject 3 was the only one with TS detectable in urine. This could be due to differences in metabolism of H2S.

Toxicological investigations in a fatal and non-fatal accident due to hydrogen sulphide (H2S) poisoning.

Hydrogen sulphide (H2S) is one of the most toxic natural gas and represents a not rare cause of fatal events in workplaces. We report here a serious accidental poisoning by hydrogen sulphide inhalation involving six sailors. Three of them died while the other three survived and were transported to the emergency room. No greenish discolouration of the body, that could be a feature of these type of deaths, was observed at autopsy. Given that blood and/or urine H2S detection does not allow to discriminate if it is related to inhalation or to putrefactive processes, the determination of thiosulphate, H2S main metabolite, is decisive. The succession of fatal events reported here can be rebuilt by toxicological data interpretation: the subject 1 died after a longer interval of time as demonstrated by the highest blood and urine thiosulfate concentrations; the subject 2 died after a short interval of time as showed by a lower blood and urine thiosulfate concentrations than subject 1; the subject 3 died almost immediately after H2S inhalation since he showed the lowest blood thiosulfate concentration, and no trace of sulphide and thiosulfate was found in the urine.

[Lung cancer deaths attributable to ambient PM(2.5) exposure in 2016 in China].

Objective: To analyze the lung cancer deaths attributable to ambient PM(2.5) exposure in China in 2016. Methods: All data were from the Global Burden of Disease Study 2016 (GBD 2016). Multiple-source data, including satellite observation, ground measurement, chemical migration model simulation, etc., and the data integration model for air quality (DIMAQ) were used to estimate the grid-level exposure to ambient PM(2.5). Data from the vital registry and cancer registry were used to establish statistical model to estimate the lung cancer deaths by province, age and gender. The lung cancer deaths attributable to PM(2.5) were calculated based on the calculation of population attributable fraction (PAF). The GBD world population age structure was adopted to calculate age-standardized rates for comparison among provinces (including 31 provinces, autonomous regions and municipalities directly under the central government, as well as Hong Kong and Macao special administrative regions, excluding Taiwan of China). Results: In 2016, the lung cancer deaths attributable to ambient PM(2.5) exposure in China were 14.56×10(4) (95% uncertainty interval (UI): 9.63×10(4)-19.55×10(4)), accounting for 24.66% (95%UI: 16.38%-33.12%) of total lung cancer deaths. The lung cancer death rate attributable to PM(2.5) increased with age, with the lowest among 25-29 age group (0.25/10(5), 95%UI: 0.17/10(5)-0.34/10(5)), the highest among ≥80 age group (90.70/10(5), 95%UI: 59.85/10(5)-122.20/10(5)). The lung cancer death rate attributable to PM(2.5) among males (14.84/10(5), 95%UI: 9.78/10(5)-19.93/10(5)) was higher than that in females (6.21/10(5), 95%UI: 4.07/10(5)-8.40/10(5)). The age-standardized death rates (ASDR) of lung cancer attributable to PM(2.5) among males and females in China were higher than the global average level. The attributable ASDR of lung cancer varied among provinces, highest in Shandong (13.51/10(5), 95%UI: 9.14/10(5)-18.20/10(5)) and lowest in Tibet (0.85/10(5), 95%UI: 0.44/10(5)-1.51/10(5)). Conclusion: In 2016, the lung cancer deaths attributable to ambient PM(2.5) exposure in China was heavy, and varied in different age groups, genders and provinces.

Inhalation poisoning with palytoxin from aquarium coral: case description and safety advice.

Palythoa spp. corals and some other marine organisms contain one of the most poisonous substances ever known - palytoxin (PTX). Due to their modest life requirements and ease of breeding, these corals are popular in home aquariums. Here we refer to a case of PTX poisoning of a middle-aged woman who inhaled poisonous vapours while brushing the corals from live rock and compare it with the available literature. As the case revealed that the symptoms of PTX poisoning are not specific and neither is treatment, our aim was to give a brief tabulated review of the symptoms that may indicate such poisoning. Cases of palytoxin poisoning have been reported worldwide, and severe ones (mostly due to ingestion of contaminated sea food) can end in death. As it appears, most (if not all) poisonings result from unawareness of the risk and reckless handling by aquarists. This is one of the first articles which provides some practical advice about the use of personal protection equipment, including gloves, masks, eyewear, and other clothing during any coral manipulation to minimise the risk. We also draw attention to the lack of marketing/trading regulations for dangerous coral species and/or regulations or instructions dealing with their removal and health protection.

Understanding the importance of key risk factors in predicting chronic bronchitic symptoms using a machine learning approach.

BACKGROUND: Chronic respiratory symptoms involving bronchitis, cough and phlegm in children are underappreciated but pose a significant public health burden. Efforts for prevention and management could be supported by an understanding of the relative importance of determinants, including environmental exposures. Thus, we aim to develop a prediction model for bronchitic symptoms. METHODS: Schoolchildren from the population-based southern California Children's Health Study were visited annually from 2003 to 2012. Bronchitic symptoms over the prior 12 months were assessed by questionnaire. A gradient boosting model was fit using groups of risk factors (including traffic/air pollution exposures) for all children and by asthma status. Training data consisted of one observation per participant in a random study year (for 50% of participants). Validation data consisted of: (1) a random (later) year in the same participants (within-participant); (2) a random year in participants excluded from the training data (across-participant). RESULTS: At baseline, 13.2% of children had asthma and 18.1% reported bronchitic symptoms. Models performed similarly within- and across-participant. Previous year symptoms/medication use provided much of the predictive ability (across-participant area under the receiver operating characteristic curve (AUC): 0.76 vs 0.78 for all risk factors, in all participants). Traffic/air pollution exposures added modestly to prediction as did body mass index percentile, age and parent stress. CONCLUSIONS: Regardless of asthma status, previous symptoms were the most important predictors of current symptoms. Traffic/air pollution variables contribute modest predictive information, but impact large populations. Methods proposed here could be generalized to personalized exacerbation predictions in future longitudinal studies to support targeted prevention efforts.

[Multi-site analysis of acute effects of air pollutants combination exposure on mortality in Jiangsu Province, China].

Objective: To explore the acute effect of fine particulate matters (PM(2.5)), O(3), NO(2) on daily non-accidental mortality, cardiovascular disease mortality and respiratory mortality data in thirteen cities of Jiangsu province. Methods: Daily average concentrations of non-accidental mortality, cardiovascular disease mortality, respiratory mortality data and environmental data were collected from January 1, 2015 to December 31, 2017 in thirteen cities of Jiangsu Province. Daily air quality, mortality and meteorology data were collected from the Information System of Air Pollution and Health Impact Monitoring of Chinese Center for Disease Control and Prevention. We used generalized additive model to evaluate the association between daily concentrations of air pollutants and mortality at single-city level and multi-city level, after adjusting the long-term and seasonal trend, as well as meteorological factors and the effect of "days and weeks" . A multivariate Meta-analysis with random effects was applied to estimate dose-response relationship between air pollutants and mortality. Results: At multi-city level, per interquartile range increase of PM(2.5), O(3), NO(2) was associated with an increase of 1.10% (95%CI: 0.66%, 1.54%), 0.59% (95%CI: 0.18%, 1.00%), 2.00% (95%CI: 1.29%, 2.72%) of daily non-accidental mortality respectively; 1.01% (95%CI: 0.63%, 1.38%), 0.66% (95%CI: 0.02%, 1.30%), 1.62% (95%CI: 1.00%, 2.23%) of daily cardiovascular mortality respectively; 1.09% (95%CI: 0.35%, 1.82%), 0.44% (95%CI: -0.29%, 1.16%), 2.75% (95%CI: 1.42%, 4.08%) of daily respiratory mortality respectively. The air pollutants effect varied across different cities. The strongest effect of PM(2.5) was current day (excess risk (ER)=1.10%, 95%CI: 0.66%, 1.54%)), the strongest effect of O(3) was 2-day lag (ER=1.82%, 95%CI: 0.69%, 2.97%) and the strongest effect of NO(2) was 1-day lag (ER=2.09%, 95%CI: 1.34%, 2.83%) of daily non-accidental mortality respectively. Conclusion: The increases of PM(2.5) and NO(2) concentration could result in the increases of daily non-accidental mortality, cardiovascular disease mortality and respiratory mortality. O(3) could result in the increases of daily non-accidental mortality and cardiovascular disease mortality. The acute effects for non-accidental mortality from high to low were NO(2), PM(2.5) and O(3,) and the strongest effect of PM(2.5) was current day. O(3) and NO(2) had lagged effects.

Congenital scoliosis: an anomalous association with endosulfan.

Endosulfan is an organochlorine pesticide that is used extensively across the world to kill insects. Incidence of acute and chronic toxicity with endosulfan poisoning has been reported, and nearly 80 countries have banned its use. However, it is still being used in many low-income/middle-income countries. One of the most severe tragedies because of endosulfan poisoning has taken place in the Indian state of Kerala due to persistent aerial spraying of endosulfan. Even though there are reports of skeletal and other congenital abnormalities in humans and experimental animals following exposure to endosulfan, very few have been documented. We report two cases of congenital scoliosis in siblings living in a community affected by high levels of endosulfan in the environment. High index of suspicion is essential during the screening of school children exposed to endosulfan. Congenital scoliosis is a progressive deformity that leads to severe disability, unless detected and corrected at an early stage.

Hydrogen sulfide gas poisoning in fish garbage room: A report of a fisherman.

We report the case of a fisherman who was exposed to high concentrations of hydrogen sulfide (H2S) gas from the fish garbage room. The patient survived and was discharged with full recovery from the hospital. H2S is a colourless, foul smelling and highly toxic gas next to carbon monoxide, which causes inhalation death. It is a by-product of various industrial processes particularly involves exposure from agriculture, petrochemical industry and organic matter decomposition from sewage processing. It is a by-product of H2S has been referred as the "knock down gas" because inhalation of high concentrations can cause immediate loss of consciousness and death. Although early use of amyl nitrate and hyperbaric oxygen shows some benefit in literature, supportive care remains the mainstay of treatment. Emergency physicians and pre-hospital care personnel are not very familiar with such exposure due to its rarity. This becomes more relevant in the developing world settings where there are rising concerns about the unsafe exposure to hazardous chemicals and its impact on human health. Emergency physicians working in Pakistan should be aware of this entity especially in regard to fishermen presenting to the Emergency Department with such a clinical presentation and its toxic manifestations. This incident also illustrates the need of enforcement of health and safety regulations in the fishing industry.

The Effects of Formaldehyde on Cytochrome P450 Isoform Activity in Rats.

Formaldehyde (FA) is an occupational and indoor pollutant. Long-term exposure to FA can irritate the respiratory mucosa, with potential carcinogenic effects on the airways. The effects of acute FA poisoning on the activities of CYP450 isoforms CYP1A2, CYP2C11, CYP2E1, and CYP3A2 were assessed by determining changes in the pharmacokinetic parameters of the probe drugs phenacetin, tolbutamide, chlorzoxazone, and testosterone, respectively. Rats were randomly divided into three groups: control, low FA dose (exposure to 110 ppm for 2 h for 3 days), and high FA dose (exposure to 220 ppm for 2 h for 3 days). A mixture of the four probe drugs was injected into rats and blood samples were taken at a series of time points. Plasma concentrations of the probe drugs were measured by HPLC. The pharmacokinetic parameters t1/2, AUC(0-t), and Cmax of tolbutamide, chlorzoxazone, and testosterone increased significantly in the high dose versus control group (P < 0.05), whereas the CL of chlorzoxazone and testosterone decreased significantly (P < 0.05). However, t1/2, AUC(0-t), and Cmax of phenacetin decreased significantly (P < 0.05), whereas the CL of phenacetin increased significantly (P < 0.05) compared to controls. Thus, acute FA poisoning suppressed the activities of CYP2C11, CYP2E1, and CYP3A2 and induced the activity of CYP1A2 in rats. And the change of CYP450 activity caused by acute FA poisoning may be associated with FA potential carcinogenic effects on the airways.