National and sub-national age-sex specific and cause-specific mortality and disability-adjusted life years (DALYs) attributable to household air pollution from solid cookfuel use (HAP) in Iran, 1990-2013

Health risk assessment of workers exposed to lead dust in informal e-waste recycling workshops

Informal recycling of electronic waste (e-waste) has attracted significant attention due to its economic benefits and rapid growth rate in many parts of the world. Unfortunately, unsafe conditions of recycling workshops possess chronic exposure to workers and lead to elevated blood lead concentrations (BLCs). Upon measuring the lead concentration in the dust of recycling workshops and the e-wastes in southwestern region of Iran, the related health risks were assessed in 30 exposed workers and 30 non-exposed habitants cases based on the determination of BLC. The average BLCs in exposed workers and non-exposed habitants cases were 24 μg/dL and 7 μg/dL, respectively. The geo-accumulation index (Igeo) revealed heavy contamination of dust in informal e-waste recycling workshops (IERWs) (5023 μg/kg) and significantly lower levels in unexposed areas (49 μg/kg). Health risk assessment indicated that lead exposure from IERWs appears to be a potential threat to workers and indirectly to their families.

Global burden of tracheal, bronchus, and lung cancer attributable to occupational carcinogens in 204 countries and territories, from 1990 to 2019: results from the global burden of disease study 2019

BACKGROUND

Occupational-related cancers are a substantial global health issue. The largest proportion of occupational-related cancers is tracheal, bronchus, and lung (TBL) cancer. This study aimed to explore the geographical and temporal trends in occupational carcinogens related to TBL cancer.

METHODS

Data on TBL cancer attributable to occupational carcinogens were collected from the Global Burden of Disease Study 2019. Numbers and age-standardized rates (ASRs) of deaths, disability-adjusted life years (DALYs), and corresponding average annual percentage change (AAPC) were evaluated and stratified by geographic location, socio-demographic index (SDI) quintiles, age, and sex.

RESULTS

Globally, ASRs of deaths and DALYs in TBL cancer attributable to occupational carcinogens showed a downward trend (AAPC = - 0.69%, - 1.01%) while increases were observed in the low, low-middle, and middle SDI quintiles. Although males accounted for 82.4% and 81.5% of deaths and DALYs in 2019, respectively, it showed an upward trend of ASRs in females (AAPC = 0.33%, 0.02%). Occupational exposure to asbestos, silica and diesel engine exhaust were the top three causes of age-standardized TBL cancer deaths and DALYs. Over the past three decades, the percentage of age-standardized TBL cancer deaths and DALYs attributable to occupational asbestos and silica exposure decreased by 18.24, 6.71 and 20.52%, 4.00% globally, but increased significantly in lower SDI regions, while the burden attributable to occupational diesel engine exhaust exposure increased by 32.76, 37.23% worldwide.

CONCLUSIONS

Occupational exposure remains an important risk factor for TBL cancer. The burden of TBL cancer attributable to occupational carcinogens showed obvious heterogeneity which decreased in higher SDI but increased in lower SDI regions. The burden of males was significantly higher than females, but the females showed an increasing trend. Occupational exposure to asbestos was the main causes of the burden. Therefore, effective prevention and control measures tailored to local conditions are necessary.

Burden of injury due to occupational accidents and its spatiotemporal trend at the national and subnational levels in Iran, 2011-2018

PURPOSE

The spatiotemporal trend of the burden of injury due to occupational accidents in Iran, 2011-2018 were assessed at the national and subnational levels.

METHODS

The burden of occupational injury was estimated using three datasets of occupational injury data, the employed population, and duration and disability weight of injuries.

RESULTS

The disability-adjusted life years (DALYs), deaths, DALY rate, and death rate (per 100,000 workers) of occupational injury in Iran drastically decreased from 169,523, 2,280, 827, and 11 in 2011 to 86,235, 1,151, 362, and 5 in 2018, respectively. The DALY rates of occupational injury were significantly different by gender and age in a manner that the DALY rate of men was much higher than that of women and the DALY rates by age group in 2018 ranged from 98 for 50 y and over to 901 for 15-19 y. The shares of injury outcomes in the total DALYs in 2018 were as follows: 63.6% for fatal injuries, 17.4% for fracture, 7.9% for open wound, 7.3% for amputation, and 3.8% for other injuries. Over 83% of the DALYs was observed in three economic activity groups of construction, manufacturing, and community, social, and personal service activities. The three provinces with the highest DALY rates in 2018 were Markazi, West Azarbaijan, and East Azarbaijan, respectively.

CONCLUSION

Despite the decreasing temporal trend, the burden of occupational injury in Iran in 2018 was high. The high-risk groups and hot spot provinces should be taken into more consideration for further reduction of the injury burden.

A joinpoint and age-period-cohort analysis of ocular cancer secular trends in Iran from 2004 to 2016

Investigating secular trends of ocular cancer registration in Iran. After acquiring Iranian national population-based cancer registry data, trends of age-standardised incidence rates (ASIR) of ocular cancers and annual percent changes (APC) between 2004 and 2016 were analysed in age groups, gender, topography and morphology types with joinpoint regression analysis. Age, period, and cohort effects on incidence rates were estimated by age-period-cohort model. Geographic distribution of ASIR was assessed using GIS. Overall ASIR of ocular cancers was 16.04/100,000 (95% CI 15.77-16.32). Joinpoint regression analysis showed a significant increase of ASIR between 2004 and 2009 for males (APC = 5.5, 95% CI  0.9-10.2), ages over 50 years (APC = 5.2, 1.2-9.4), skin/canthus/adnexal cancers (APC = 4.2, 0.8-7.7), and carcinomas/adenocarcinomas (APC = 4.3, 0.6-8.1); however, between 2009 and 2016 a declining trend was observed in all investigated variables. ASIR of retinoblastoma was significantly increased (averaged APC = 20.7, 9-33.7) between 2004 and 2016. age-period-cohort analyses showed that incidence rates of ocular cancers significantly increased with aging, time periods, and birth cohort effects (p < 0.001). ASIR varied from 6.7/100,000 to 21.7/100,000 in Iran. Excepting retinoblastoma, all ocular cancer incidence trends were downward over a 13-year period; however, it was increasing between 2004 and 2009 cancer. ASIR was significant aging in Iran.

Assessment of cause-specific mortality and disability-adjusted life years (DALYs) induced by exposure to inorganic arsenic through drinking water and foodstuffs in Iran

The health risk and burden of disease induced by exposure to inorganic arsenic (iAs) through drinking water and foodstuffs in Iran were assessed. The iAs levels in drinking water and foodstuffs (15 food groups) in the country were determined through systematic review of three international databases (PubMed, Scopus, and Web of Science) and meta-analysis. Based on the results of the systematic review and meta-analysis, the average iAs levels in drinking water and all the food groups at the national level were lower than the maximum permissible levels. The total average non-carcinogenic risk of dietary exposure to iAs in terms of hazard index (HI) was 3.4. The average incremental lifetime cancer risk (ILCR) values of dietary exposure to iAs were determined to be 1.5 × 10^-3 for skin cancer, 1.0 × 10^-3 for lung cancer, and 4.0 × 10^-4 for bladder cancer. Over two-thirds of the non-carcinogenic and carcinogenic risk of dietary exposure to iAs was attributed to bread and cereals, drinking water, and rice. The total annual cancer incidence, deaths, disability-adjusted life years (DALYs), death rate, and DALY rate (per 100,000 people) were assessed to be 3347 (95 % uncertainty interval: 1791 to 5999), 1302 (697 to 2336), 72,606 (38,833 to 130,228), 1.6 (0.87 to 2.9), and 91 (49 to 160). The contribution of mortality in the attributable burden of disease was 95.1 %. The contributions of the causes in the attributable burden of disease were 72 % for lung cancer, 16 % for bladder cancer, and 12 % for skin cancer. Due to the significant attributable burden of disease, national and subnational action plans consisting of multi-disciplinary approaches for risk management of dietary exposure to iAs, especially for the higher arsenic-affected areas and high-risk population groups in the country are recommended.

Assessment of burden of disease induced by exposure to heavy metals through drinking water at national and subnational levels in Iran, 2019

The burden of disease attributable to exposure to heavy metals via drinking water in Iran (2019) was assessed at the national and regional levels. The non-carcinogenic risk, carcinogenic risk, and attributable burden of disease of heavy metals in drinking water were estimated in terms of hazard quotient (HQ), incremental lifetime cancer risk (ILCR), and disability-adjusted life year (DALY), respectively. The average drinking water concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and nickel (Ni) in Iran were determined to be 2.3, 0.4, 12.1, 2.5, 0.7, and 19.7 μg/L, respectively, which were much lower than the standard values. The total average HQs of heavy metals in drinking water in the entire country, rural, and urban communities were 0.48, 0.65 and 0.45, respectively. At the national level, the average ILCRs of heavy metal in the entire country were in the following order: 1.06 × 10^-4 for As, 5.89 × 10^-5 for Cd, 2.05 × 10^-5 for Cr, and 3.76 × 10^-7 for Pb. The cancer cases, deaths, death rate (per 100,000 people), DALYs, and DALY rate (per 100,000 people) attributed to exposure to heavy metals in drinking water at the national level were estimated to be 213 (95% uncertainty interval: 180 to 254), 87 (73-104), 0.11 (0.09-0.13), 4642 (3793-5489), and 5.81 (4.75-6.87), respectively. The contributions of exposure to As, Cd, Cr, and Pb in the attributable burden of disease were 14.7%, 65.7%, 19.3%, and 0.2%, respectively. The regional distribution of the total attributable DALY rate for all heavy metals was as follows: Region 5> Region 4> Region 1> Region 3> Region 2. The investigation and improvement of relatively high exceedance of As levels in drinking water from the standard value, especially in Regions 5 and 3 as well as biomonitoring of heavy metals throughout the country were recommended.

Household Air Pollution and High Blood Pressure: A Secondary Analysis of the 2016 Albania Demographic Health and Survey Dataset

Background: Hypertension is a significant public health problem in low- and middle-income countries (LMICs). This study aimed to examine the association between household air pollution (HAP) and blood pressure using data from the 2016 Albania Demographic Health and Survey (DHS). Methods: We computed the odds ratio (OR) for the prevalence of hypertension between respondents exposed to clean fuels (e.g., electricity, liquid petroleum gas, natural gas, and biogas) and respondents exposed to polluting fuel (e.g., kerosene, coal/lignite, charcoal, wood, straw/shrubs/grass, and animal dung). Result: The results show that participants exposed to household polluting fuels in Albania were 17% more likely to develop hypertension than those not exposed to household air pollution (OR = 1.17, 95% CI 1.10 to 1.24). Subgroup analysis revealed that the odds of hypertension were more significant among women (OR = 1.22, 95% CI 1.13 to 1.31), rural residents (OR = 1.12, 95% CI 1.04 to 1.22), and participants aged >24 years (OR = 1.35, 95% CI 1.12 to 1.62) who were exposed to household polluting fuels compared to their counterparts who were not exposed. In summary, the results of the study show significant associations between household air pollution and hypertension risk overall, especially among women, rural dwellers, and people aged >24 years in Albania. Conclusion: In this study, an association between household air pollution and the risk of hypertension was found, particularly among low-income households, those with no education, women, and those who live in rural areas.

Vitamin D3 protects intrauterine growth restriction induced by cooking oil fume derived fine particulate matters

BACKGROUND

Cooking oil fume (COF) is an important source of indoor air pollution which severely affects human health, and sufficient vitamin D₃ (VitD₃) is necessary for maternal and child health. However, the effects of cooking oil fume-derived PM_2.5 (COF-PM_2.5) on birth outcomes and whether VitD₃ could protect from adverse effects caused by COFs-PM_2.5 are still unclear.

METHODS

Twenty-four pregnant rats were divided into 4 groups and treated with various treatments: normal feeding, COFs-PM_2.5 intratracheal instillation, VitD₃ intragastric administration, and COFs-PM_2.5 and VitD₃ co-treatment, respectively. The fetal rats were obtained in pregnant 21 days and the development of them was recorded. Morphological changes in umbilical cord were measured with HE staining, and the oxidative stress and inflammatory levels were also investigated. Western blotting and RT-PCR was used to detect the expression of angiogenesis related factors.

RESULTS

We successfully established an intrauterine growth restriction model in rats induced by COFs-PM_2.5 where fetus weight significantly decreased after COFs-PM_2.5 exposure. As for the umbilical cord vasculature, the wall thickened and the lumen narrowed down, and the contractility of the umbilical cord vasculature enhanced after COFs-PM_2.5 exposure. COFs-PM_2.5 exposure also increased the oxidative stress and inflammation level and activated the HIF-1α/eNOS/NO and VEGF/VEGFR2/eNOS signaling pathway. Interestingly, VitD₃ intervention significantly increased the fetus weight and attenuated the injury of umbilical cord vascular, and partly or completely reversed the changes in the ROS/eNOS/ET-1 axis caused by COF-PM_2.5.

CONCLUSIONS

The findings of this study suggested that COF-PM_2.5 exposure could contribute to intrauterine growth restriction through disturbing the ROS/eNOS/ET-1 axis, while VitD₃ supplementation could be an effective prophylactic measurement.

Burden of disease induced by public overexposure to solar ultraviolet radiation (SUVR) at the national and subnational levels in Iran, 2005-2019

Estimating the burden of diseases induced by overexposure to solar ultraviolet radiation (SUVR) can help to prioritize environmental health interventions. The age-sex specific and cause-specific mortality and disability-adjusted life years (DALYs) attributable to overexposure to SUVR at the national and subnational levels in Iran, 2005-2019 were estimated. The burden of disease induced by overexposure to SUVR was quantified in four steps as follows: (1) estimating exposure to SUVR, (2) estimating total incidences and deaths of target causes, (3) assessing population attributable fractions of the target causes for the SUVR, and (4) calculating the attributable burden of disease. The attributable DALYs, deaths, age-standardized DALY rate, and age-standardized death rate at the national level were determined to be respectively 21896, 252, 42.59, and 0.56 in 2005 and were respectively changed to 28665, 377, 38.76, and 0.53 in 2019. The contributions of causes in the attributable DALYs at the national level were different by year and sex and for both sexes in 2019 were as follows: 46.15% for cataract, 20.36% for malignant skin melanoma, 16.07% for sunburn, 12.41% for squamous-cell carcinoma, and 5.01% for the other five causes. The contributions of population growth, population ageing, risk exposure, and risk-deleted DALY rate in the temporal variations of the attributable burden of disease in the country were +20.73%, +20.68%, +2.01%, and -12.51%. The highest and lowest provincial attributable age-standardized DALY rates in 2019 were observed in Fars (46.8) and Ardebil (32.7), respectively. The burden of disease induced by exposure to SUVR caused relatively low geographical inequality in health status in Iran. Due to increasing trends of the SUVR as well as the attributable burden of disease, the preventive interventions against the SUVR overexposure should be considered in the public health action plan all across the country.

National and subnational burden of disease attributable to occupational exposure to solar ultraviolet radiation (SUVR) in Iran, 2005-2019

Overexposure to solar ultraviolet radiation (SUVR) can cause skin and eye adverse effects for outdoor workers. In this study, the burden of disease induced by occupational exposure to SUVR and its spatiotemporal trend at national and sub-national levels in Iran, 2005-2019 were assessed. The attributable burden of disease was assessed using the following five datasets: (1) distribution of occupational exposure to SUVR, (2) total incidences and deaths of health outcomes of SUVR exposure, (3) population attributable fractions of the health outcomes of SUVR exposure, (4) age-gender distribution of outdoor workers, and (5) disability-adjusted life year (DALY) calculation constants. During 2005-2019, the attributable DALYs increased from 2442 to 2907 and the attributable DALY rate (per 100,000 workers) slightly decreased from 11.94 to 11.91. The share of YLL in the attributable burden of disease was in the range of 43%-46%. Out of nine causes, about 90% of the attributable burden of disease in 2019 was related to cataracts (29.9%), malignant skin melanoma (27.4%), squamous-cell carcinoma (18.6%), and sunburn (17.2%). During the study period, the attributable DALY rate in women increased by 60.95% (from 5.04 to 8.11) and in men decreased by 2.06% (from 13.03 to 12.76). The total attributable DALYs and DALY rate rose by age during 2005-2019. The contributions of population growth, risk-deleted DALY rates, exposure risk, and population age structure in temporal changes of the attributable burden of disease were 19.27%, 9.13%, -1.35%, and -14.8%, respectively. The three highest attributable DALY rates in 2019 were observed in South Khorasan (21.28), Chahar Mahal and Bakhtiari (17.42), and Kordestan (17.26), respectively. The preventive interventions against SUVR overexposure, regular screenings, and early treatments with an emphasis on occupations with continuous sun exposure and provinces with increasing attributable DALY rates should be considered in the occupational health action plan in the country.

Spatiotemporal analysis of solar ultraviolet radiation based on Ozone Monitoring Instrument dataset in Iran, 2005-2019

The solar ultraviolet radiation (UVR) at national, provincial and county levels in Iran during 2005-2019 were determined based on Ozone Monitoring Instrument (OMI) dataset. The temporal (annual and monthly) trends and spatial distributions of the UVR in terms of erythemally weighted daily dose (EDD), erythemally weighted irradiance at local solar noon time (EDR), and UV index and the major factors influencing the spatiotemporal trends were analyzed. The population-weighted average values of EDD, EDR, and UV index in Iran were respectively 3631 J/m², 176.3 mW/m², 7.1 in 2005 and rose by 0.22% per year to 3744 J/m², 181.7 mW/m², and 7.3, respectively in 2019, but the annual trend was not statistically significant. The EDD in Iran during the study period exhibited the highest monthly average value in June (6339 J/m²) and the lowest one in December (1263 J/m²). The solar UVA/UVB ratios at the national level during 2005-2019 were considerably lower in summer. The EDD provincial average values in the study period were in the range of 2717 (Gilan) to 4424 J/m² (Fars). The spatiotemporal variations of the solar UVR parameters were well described by the linear models as a function of cloud optical thickness (COT), ozone column amount, surface albedo, latitude, and altitude (R² > 0.961, p value < 0.001) and the temporal changes of the solar UVR parameters were mainly caused by the COT. The results indicated that non-burning exposure to solar UVR in summer can be more efficient for vitamin D synthesis due to higher contribution of UVB in the solar UVR. The spatial distributions and temporal trends should be considered to determine the optimal duration, time and condition of exposure to the solar UVR for the public and occupational training and public health measures.

Long-term exposure to indoor air pollution and risk of tuberculosis

Indoor air pollution (IAP) is a recognized risk factor for various diseases. This paper examines the role of indoor solid fuel exposure in the risk of mycobacterium tuberculosis (TB) in Delhi Metropolitan, India. Using a cross-sectional design, subjects were screened for a history of active TB and lifelong exposure to IAP sources, such as solid fuel burning and kerosene. The TB prevalence rate in the study area was 1117 per 100 000 population. Every year, increase in solid fuel exposure was associated with a three percent higher likelihood of a history of active TB. Subjects exposed to solid fuel and kerosene use for both heating home and cooking showed significant associations with TB. Age, household expenditure (a proxy of income), lung function, and smoking also showed significant associations with TB. Smokers and solid fuel-exposed subjects were four times more likely to have a history of active TB than non-smoker and unexposed subjects. These finding calls strategies to mitigate solid fuel exposure, such as use of clean cookstove and ventilation, to mitigate the risk of TB which aligns with the United Nations' goal of "End TB by 2030."

Health effects of household air pollution related to biomass cook stoves in resource limited countries and its mitigation by improved cookstoves

BACKGROUND

Household air pollution (HAP) related to cooking is associated with significant global morbidity and mortality. An estimated three billion people worldwide are exposed to cooking related HAP caused by solid fuel combustion. This exposure is highest for the vulnerable population of women and children resulting in significant cumulative health effects.

METHODS

A literature review was conducted for health effects of household air pollution related to biomass cookstoves in resource limited countries and to evaluate the effect of improved cookstoves on these health effects. We searched PubMed, Embase and Cochrane Library. We conducted searches in January 2018 with a repeat in February 2020. We included only studies conducted in resource limited countries, published in English, irrespective of publication year and studies that examined the health effects of HAP and/or studied the effects of improved cookstove (IC). Two authors independently screened journal article titles, abstracts and full-text articles to identify those that included the following search term: biomass cookstoves and health risks. We also assessed the limitations of IC with barriers to their uptake.

RESULTS

Health effects associated with HAP mostly include increased blood pressure (BP), dyspnea, childhood pneumonia, lung cancer, low birthweight and cardiovascular diseases. Being a global problem with divergent environmental factors including wide variety of fuel used, housing condition, foods prepared, climatic condition and social factors; most solutions though efficient seems inadequate. Improved cookstove (IC) mitigates emissions and improves short term health, though few randomized long-term studies could substantiate its long-standing continuance and health benefits.

CONCLUSION

There is ample data about the health effects of HAP, with some benefit with IC intervention for elevated blood pressure, dyspnea symptoms, mutagenicity and cardiovascular diseases. IC does not have any benefit in pregnancy outcomes or children health.

Long-term exposure to outdoor and household air pollution and blood pressure in the Prospective Urban and Rural Epidemiological (PURE) study

Exposure to air pollution has been linked to elevated blood pressure (BP) and hypertension, but most research has focused on short-term (hours, days, or months) exposures at relatively low concentrations. We examined the associations between long-term (3-year average) concentrations of outdoor PM2.5 and household air pollution (HAP) from cooking with solid fuels with BP and hypertension in the Prospective Urban and Rural Epidemiology (PURE) study. Outdoor PM2.5 exposures were estimated at year of enrollment for 137,809 adults aged 35-70 years from 640 urban and rural communities in 21 countries using satellite and ground-based methods. Primary use of solid fuel for cooking was used as an indicator of HAP exposure, with analyses restricted to rural participants (n = 43,313) in 27 study centers in 10 countries. BP was measured following a standardized procedure and associations with air pollution examined with mixed-effect regression models, after adjustment for a comprehensive set of potential confounding factors. Baseline outdoor PM2.5 exposure ranged from 3 to 97 μg/m3 across study communities and was associated with an increased odds ratio (OR) of 1.04 (95% CI: 1.01, 1.07) for hypertension, per 10 μg/m3 increase in concentration. This association demonstrated non-linearity and was strongest for the fourth (PM2.5 > 62 μg/m3) compared to the first (PM2.5 < 14 μg/m3) quartiles (OR = 1.36, 95% CI: 1.10, 1.69). Similar non-linear patterns were observed for systolic BP (β = 2.15 mmHg, 95% CI: -0.59, 4.89) and diastolic BP (β = 1.35, 95% CI: -0.20, 2.89), while there was no overall increase in ORs across the full exposure distribution. Individuals who used solid fuels for cooking had lower BP measures compared to clean fuel users (e.g. 34% of solid fuels users compared to 42% of clean fuel users had hypertension), and even in fully adjusted models had slightly decreased odds of hypertension (OR = 0.93; 95% CI: 0.88, 0.99) and reductions in systolic (-0.51 mmHg; 95% CI: -0.99, -0.03) and diastolic (-0.46 mmHg; 95% CI: -0.75, -0.18) BP. In this large international multi-center study, chronic exposures to outdoor PM2.5 was associated with increased BP and hypertension while there were small inverse associations with HAP.

Air Microbiome and Pollution: Composition and Potential Effects on Human Health, Including SARS Coronavirus Infection

Polluted air poses a significant threat to human health. Exposure to particulate matter (PM) and harmful gases contributes to cardiovascular and respiratory diseases, including allergies and obstructive lung disease. Air pollution may also be linked to cancer and reduced life expectancy. Uptake of PM has been shown to cause pathological changes in the intestinal microbiota in mice and humans. Less is known about the effects of pollution-associated microbiota on human health. Several recent studies described the microbiomes of urban and rural air samples, of the stratosphere and sand particles, which can be transported over long distances, as well as the air of indoor environments. Here, we summarize the current knowledge on airborne bacterial, viral, and fungal communities and discuss their potential consequences on human health. The current data suggest that bacterial pathogens are typically too sparse and short-lived in air to pose a significant risk for infecting healthy people. However, airborne fungal spores may exacerbate allergies and asthma. Little information is available on viruses including phages, and future studies are likely to detect known and novel viruses with a yet unknown impact on human health. Furthermore, varying experimental protocols have been employed in the recent microbiome and virome studies. Therefore, standardized methodologies will be required to allow for better comparisons between studies. Air pollution has been linked to more severe outcomes of SARS (severe acute respiratory syndrome) coronavirus (SARS-CoV) infections. This may have contributed to severe SARS-CoV-2 outbreaks, especially those in China, Northern Italy, Iran, and New York City.

Age-sex specific and cause-specific health risk and burden of disease induced by exposure to trihalomethanes (THMs) and haloacetic acids (HAAs) from drinking water: An assessment in four urban communities of Bushehr Province, Iran, 2017

Health risk and burden of disease induced by exposure to trihalomethanes (THMs, four compounds) and haloacetic acids (HAAs, 5 compounds) from drinking water through ingestion, dermal absorption, and inhalation routes were assessed based on one-year water quality monitoring in four urban communities (Bandar Deylam, Borazjan, Bushehr, and Choghadak) of Bushehr Province, Iran. The total average concentrations of THMs and HAAs at all the communities level were determined to be 92.9 ± 43.7 and 70.6 ± 26.5 μg/L, respectively. The dominant components of the THMs and HAAs were determined to be tribromomethane (TBM, 41.6%) and monobromoacetic acid (MBAA, 60.8%), respectively. The average contributions of ingestion, dermal absorption, and inhalation routes in exposure to the chlorination by-products (CBPs) were respectively 65.0, 15.4, and 19.6%. The total average non-carcinogenic risk as the hazard index (HI) and incremental lifetime cancer risk (ILCR) of the CBPs at all the communities level were found to be 4.03 × 10^-1 and 3.16 × 10^-4, respectively. The total attributable deaths, death rate (per 100,000 people), age-weighted disability-adjusted life years (DALYs), and age-weighted DALY rate for all ages both sexes combined at all the communities level were estimated to be 1.0 (uncertainty interval: UI 95% 0.3 to 2.8), 0.27 (0.08-0.75), 30.8 (11.3-100.1), and 8.1 (3.0-26.4), respectively. The average contribution of mortality (years of life lost due to premature mortality: YLLs) in the attributable burden of disease was 94.7% (94.4-95.6). Although in most of cases the average levels of the CBPs were in the permissible range of Iranian standards for drinking water quality, the average values of ILCRs as well as attributable burden of disease were not acceptable (the ILCRs were higher than the boundary limit of 10^-5); therefore, implementation of interventions for reducing exposure to CBPs through drinking water especially in Kowsar Dam Water Treatment Plant is strictly recommended.

The disease burden attributable to 18 occupational risks in China: an analysis for the global burden of disease study 2017

BACKGROUND

China has more than 18% of the global population and over 770 million workers. However, the burden of disease attributable to occupational risks is unavailable in China. We aimed to estimate the burden of disease attributable to occupational exposures at provincial levels from 1990 to 2017.

METHODS

We estimated the summary exposure values (SEVs), deaths and disability-adjusted life years (DALYs) attributable to occupational risk factors in China from 1990 to 2017, based on Global Burden of Disease Study (GBD) 2017. There were 18 occupational risks, 22 related causes, and 35 risk-outcome pairs included in this study. Meanwhile, we compared age-standardized death rates attributable to occupational risk factors in provinces of China by socio-demographic index (SDI).

RESULTS

The SEVs of most occupational risks increased from 1990 to 2017. There were 323,833 (95% UI 283,780 - 369,061) deaths and 14,060,210 (12,022,974 - 16,125,763) DALYs attributable to total occupational risks in China, which were 27.9 and 22.1% of corresponding global levels, respectively. For attributable deaths, major risks came from occupational particulate matter, gases, and fumes (PGFs), and for the attributable DALYs, from occupational injuries. The attributable burden was higher in males than in females. Compared with high SDI provinces, low SDI provinces, especially Western China, had higher death rates attributable to total occupational risks, occupational PGFs, and occupational injuries.

CONCLUSION

Occupational risks contribute to a huge disease burden in China. The attributable burden is higher in males, and in less developed provinces of Western China, reflecting differences in risk exposure, socioeconomic conditions, and type of jobs. Our study highlights the need for further research and focused policy interventions on the health of workers especially for less developed provinces in China to reduce occupational health losses effectively.

Cooking fuel decision-making and family structure: a field study in China

Household air pollution caused by solid fuel use for cooking is prevalent in rural China and generates various environmental and health problems. Various potential impact factors on cooking fuel decision such as income, education, modern energy, and infrastructure are examined. However, the role of family structures has been ignored. A survey on household energy consumption pattern interrelating socio-economic and demographic factors was conducted in ten villages in Northern China using stratified random sampling technique. The number of family member eating together influences households' cooking fuel decision-making significantly. The numbers of school-age children and family members under 6 and above 60 years old have no significant influence on the household's cooking fuel decision-making respectively. Compared with families with neither child nor the elderly, those with no child but at least an elderly member have 0.103 lower probability of choosing clean fuels as their primary cooking fuel. Hence, the elderly owns a heavyweight in the household fuel decision-making process in rural China, and the government should formulate policies more in line with the background of the times to deal with rural energy issues.

Age-sex specific disability-adjusted life years (DALYs) attributable to elevated levels of fluoride in drinking water: A national and subnational study in Iran, 2017

National and subnational burden of disease attributable to elevated fluoride levels in drinking water apportioned by sex, age group, province, and community type in Iran, 2017 were quantified based on disability-adjusted life years (DALYs). The attributable burden of disease was estimated using four input data: (1) effect size of elevated drinking water fluoride levels for dental and skeletal fluorosis, (2) population distribution of drinking water fluoride levels, (3) the threshold levels of fluoride in drinking water for contribution in dental and skeletal fluorosis, and (4) age-sex distribution of population. The attributable burden of disease was only related to dental fluorosis, because the fluoride levels were lower than the threshold value for skeletal fluorosis (4.0 mg/L) in all of the cases. The national attributable prevalence (per 100,000 people), DALYs, and DALY rate in 2017 were calculated to be 60 (95% uncertainty interval 48-69), 3443 (1034-6940), and 4.31 (1.29-8.68), respectively. The national attributable burden of disease was not significantly different by sex, but was affected by age and community type in a manner that the highest DALY rate was related to the age group 10-14 y (6.06 [1.82-12.21]) and over 66% of the national attributable DALYs occurred in rural communities. The attributable burden of disease occurred only in 10 out of 31 provinces and about 94% of the attributable DALYs were concentrated in four provinces Fars (1967 [592-3964]), Bushehr (414 [124-836]), West Azarbaijan (400 [120-808]), and Hormozgan (377 [113-761]). Implementation of fluoride-safe drinking water supply schemes in the four leading provinces can prevent most of the national health losses and partly compensate the increasing trend of disease burden from oral conditions at the national level.

Health risk of phthalates in water environment: Occurrence in water resources, bottled water, and tap water, and burden of disease from exposure through drinking water in tehran, Iran

Occurrence of phthalates in water resources, bottled water, and tap water, and health risk of exposure to the phthalates through drinking water in Tehran, Iran, 2018 were studied. The six phthalates with the most health and environmental concerns, including di-(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), di-n-butyl phthalate (DBP), diethyl phthalate (DEP), dimethyl phthalate (DMP), and di-n-octyl phthalate (DNOP) were monitored in drinking water and water resources. The average levels (±standard deviation: SD) of the total phthalates in drinking water from the water distribution system, bottled water, surface waters, and ground waters were determined to be 0.76 ± 0.19, 0.96 ± 0.10, 1.06 ± 0.23, and 0.77 ± 0.06 μg/L, respectively. The dominant compounds in the phthalates were DMP and DEHP causing a contribution to the total phthalate levels higher than 60% in all the water sources. The phthalate levels of drinking water significantly increased by contact of hot water with disposable plastic and paper cups and by sunlight exposure of bottled water (p value < 0.05). The hazard quotients (HQs) of DEHP, BBP, DBP, and DEP for all ages both sexes combined were determined to be 1.56 × 10^-4, 1.01 × 10^-5, 1.80 × 10^-5, and 1.29 × 10^-6, respectively that were much lower than the boundary value of 1.0. The disability-adjusted life years (DALYs) and DALY rate (per 100,000 people) attributable to DEHP intake through drinking water for all ages both sexes combined were estimated to be 6.385 (uncertainty interval: UI 95% 1.892 to 22.133), and 0.073 (0.022-0.255), respectively. The proportion of mortality in the attributable DALYs was over 96%. The attributable DALY rate exhibited no significant difference by sex, but was considerably affected by age in a manner that the DALY rates ranged from 0.052 (0.015-0.175) in the age group 65 y plus to 0.099 (0.026-0.304) in the age group 5 to 9 y. Both the carcinogenic and non-carcinogenic health risks of the phthalates in drinking water were considered to be very low. The results can also be of importance in terms of developing frameworks to expand the domain of burden of disease study to the other environmental risks.

Exposure to Secondhand Tobacco Smoke at Airport Terminals

Background

Airports may represent significant sources of secondhand smoke (SHS) exposure for both travelers and employees. While previously common smoking rooms have largely disappeared from US airports, smoking continues to occur outdoors at terminal entrances. SHS may be especially high at arrival areas, since they oftentimes are partially enclosed by overhead departures, creating stagnant microenvironments. This study assessed particulate matter <2.5 microns in diameter (PM2.5), a common surrogate for SHS, at airport terminal locations to evaluate both outdoor exposure risk and possible indoor drift of SHS from outdoor sources.

Methods

A convenience sample of nine airport terminal arrival areas in the US state of Florida was surveyed between February and July 2018. PM2.5 levels were assessed outdoors and indoors at terminal entrances and at control areas far into terminal interiors. We also examined the impact of smoking location on SHS exposure by correlating cigarette and passing vehicle counts with PM2.5 levels at terminals with contrasting proximity of designated smoking locations to terminal entrances.

Results

Although outdoor PM2.5 levels (mean 17.9, SD 6.1 µg/m³) were significantly higher than indoors (p < 0.001), there was no difference between indoor areas directly inside terminal entrances and areas much further interior (mean 8.8, SD 2.6 vs mean 8.5, SD 3.0 µg/m³, p=0.49). However, when smoking areas were in close proximity to terminal entrances, the number of lit cigarettes and vehicular traffic per minute predicted 70% of the variance of PM2.5 levels (p < 0.001), which was attributable mostly to the cigarette number (β = 0.83; 95% CI (0.55 to 1.11); p < 0.001). This effect was not observed at smoking areas further away.

Conclusion

PM2.5 data did not suggest indoor drift from outside smoking. Nevertheless, absolute exposure outdoors was high and correlated with the location of designated smoking areas. Further studies are needed to examine the effect of microclimate formation on exposure risk.

The clinical outcomes of S-1 plus cisplatin for patients with advanced gastric cancer: A meta-analysis and systematic review

BACKGROUND

To evaluate the clinical outcomes of S-1 plus cisplatin (SC) for the treatment of patients with advanced gastric cancer (AGC).

METHODS

A systematic literature search was conducted by searching PubMed, the Cochrane Library, Embase, China Biology Medicine disc (CBMdisc), China National Knowledge Infrastructure (CNKI), and WanFang Database, for all year up to January 2017. Pooled analyses of overall survival (OS), progress-free survival rates, and adverse events were performed.

RESULTS

A total of 8 random controlled trails (RCTs) consisting of 2699 patients with AGC were selected and included in this meta-analysis. The results of our meta-analysis showed that AGC patients who treated with SC regimen receive a similar OS (HR = 1.01, 95%CI: 0.86-1.18, P = .928), PFS (HR = 0.89, 95%CI: 0.72-1.09, P = .263), and overall response rate (HR = 0.88, 95%CI: 0.70-1.11, P = .283). However, SC regimen may increase the risk of 1 to 2 grade (OR = 1.128, 95%CI: 1.075-1.184, P = .000) and 3 to 4 grade (OR = 1.24, 95%CI: 1.01-1.52, P = .039) adverse events.

CONCLUSION

SC chemotherapy showed no difference in survival compared with 5-FU- and S-1-based other therapy, but has a higher rate of adverse events compared with other chemotherapy regimens.

Age-sex specific and sequela-specific disability-adjusted life years (DALYs) due to dental caries preventable through water fluoridation: An assessment at the national and subnational levels in Iran, 2016

We assessed disability-adjusted life years (DALYs) due to dental caries preventable through water fluoridation apportioned by sex, age group, sequela, province, and community type in Iran, 2016. The burden of disease due to dental caries was extracted from the Global Burden of Disease Study 2016 (GBD 2016) and the caries preventive effect of water fluoridation was calculated using a database of fluoride levels in drinking water. All the preventable DALYs were caused by years lived with disability (YLDs) because of the non-fatal character of dental caries. DALYs and DALY rate (per 100,000 people) preventable through water fluoridation at the national level in 2016 were 14,971 (95% uncertainty interval 7348- 24,725) and 18.73 (9.19-30.93), respectively. The national population preventable fraction (PPF) of dental caries by water fluoridation was determined to be as high as 0.176 (0.141-0.189). The share of sequelae in the preventable DALYs at the national level were estimated to be 76.8% for edentulism and severe tooth loss, 21.4% for caries of permanent teeth, and 1.8% for caries of deciduous teeth. The national DALYs and DALY rate preventable through water fluoridation exhibited no difference by sex, but considerably increased by age from 110 (37-223) and 1.5 (0.5-3.1) for the age group 0-4 y to 4331 (2334-6579) and 88.9 (47.9-135.1) for the age group 65 y and older, respectively. Over 80% of the national preventable DALYs occurred in urban areas due to higher population and lower coverage of fluoridated drinking water. The highest provincial DALYs and DALY rate preventable by water fluoridation were observed in Tehran and Gilan to be 3776 (1866-6206) and 37.2 (18.6-60.8), respectively. The results indicated that water fluoridation can play a profound role in the promotion of dental public health and compensate the spatial inequality and increasing temporal trend of health losses from dental caries at the national level.

National and subnational mortality and disability-adjusted life years (DALYs) attributable to 17 occupational risk factors in Iran, 1990-2015

We estimated age-sex specific and cause-specific mortality, years of life lost due to premature mortality (YLLs), years lived with disability (YLDs) and disability-adjusted life years (DALYs) attributable to 17 individual occupational risks in Iran at the national and subnational levels in 1990-2015 based on the Global Burden of Disease Study 2015 (GBD 2015). The burden of disease attributable to occupational risk factors was calculated using the comparative risk assessment methodology based on 10 outcomes and 21 risk-outcome pairs. The temporal changes in the attributable burden of disease were decomposed into the contribution of population growth, population ageing, risk-deleted DALY rate, and risk exposure. National DALYs attributable to occupational risks at the national level in 1990, 2005, and 2015 were 138,210 (95% uncertainty interval 64,429-223,028), 193,243 (91,645-310,281), and 228,310 (106,782-371,709), respectively indicating a total increase of 65% (65-67) during the study period. Between 1990 and 2015, the share of the attributable DALYs for women rose by 55% (51-58) from 13% (12-14) to 20% (19-21). The proportion of YLLs in national DALYs attributable to occupational risks during the study period slightly decreased from 24% in 1990 to 23% in 2015. The five occupational risks with the highest contributions in the national attributable DALYs in 2015 were ergonomic factors (107,490), noise (52,122), exposure to particulate matter, gases, and fumes (26,847), asthmagens (19,347), and exposure to asbestos (7842). From 1990 to 2015, the increase in total DALYs attributable to occupational carcinogens (112%) was higher than that for other occupational risks. During the study period, changes in risk deleted DALY rate and risk exposure led to decreases in total DALYs attributable to occupational risks by 14% and 30%, respectively. Based on the Gini coefficient, spatial inequality in DALY rate attributable to occupational risks at the provincial level decreased during 1990-2015. A comprehensive plan for management of exposure to occupational risks, especially occupational carcinogens can cause an important effect for control of the increasing trend of occupational health losses.

Characterizing exposure to household air pollution within the Prospective Urban Rural Epidemiology (PURE) study

BACKGROUND

Household air pollution (HAP) from combustion of solid fuels is an important contributor to disease burden in low- and middle-income countries (LIC, and MIC). However, current HAP disease burden estimates are based on integrated exposure response curves that are not currently informed by quantitative HAP studies in LIC and MIC. While there is adequate evidence supporting causal relationships between HAP and respiratory disease, large cohort studies specifically examining relationships between quantitative measures of HAP exposure with cardiovascular disease are lacking.

OBJECTIVE

We aim to improve upon exposure proxies based on fuel type, and to reduce exposure misclassification by quantitatively measuring exposure across varying cooking fuel types and conditions in diverse geographies and socioeconomic settings. We leverage technology advancements to estimate household and personal PM2.5 (particles below 2.5 μm in aerodynamic diameter) exposure within the large (N~250,000) multi-country (N~26) Prospective Urban and Rural Epidemiological (PURE) cohort study. Here, we detail the study protocol and the innovative methodologies being used to characterize HAP exposures, and their application in epidemiologic analyses.

METHODS/DESIGN

This study characterizes HAP PM2.5 exposures for participants in rural communities in ten PURE countries with >10% solid fuel use at baseline (Bangladesh, Brazil, Chile, China, Colombia, India, Pakistan, South Africa, Tanzania, and Zimbabwe). PM2.5 monitoring includes 48-h cooking area measurements in 4500 households and simultaneous personal monitoring of male and female pairs from 20% of the selected households. Repeat measurements occur in 20% of households to assess impacts of seasonality. Monitoring began in 2017, and will continue through 2019. The Ultrasonic Personal Aerosol Sampler (UPAS), a novel, robust, and inexpensive filter based monitor that is programmable through a dedicated mobile phone application is used for sampling. Pilot study field evaluation of cooking area measurements indicated high correlation between the UPAS and reference Harvard Impactors (r = 0.91; 95% CI: 0.84, 0.95; slope = 0.95). To facilitate tracking and to minimize contamination and analytical error, the samplers utilize barcoded filters and filter cartridges that are weighed pre- and post-sampling using a fully automated weighing system. Pump flow and pressure measurements, temperature and RH, GPS coordinates and semi-quantitative continuous particle mass concentrations based on filter differential pressure are uploaded to a central server automatically whenever the mobile phone is connected to the internet, with sampled data automatically screened for quality control parameters. A short survey is administered during the 48-h monitoring period. Post-weighed filters are further analyzed to estimate black carbon concentrations through a semi-automated, rapid, cost-effective image analysis approach. The measured PM2.5 data will then be combined with PURE survey information on household characteristics and behaviours collected at baseline and during follow-up to develop quantitative HAP models for PM2.5 exposures for all rural PURE participants (~50,000) and across different cooking fuel types within the 10 index countries. Both the measured (in the subset) and the modelled exposures will be used in separate longitudinal epidemiologic analyses to assess associations with cardiopulmonary mortality, and disease incidence.

DISCUSSION

The collected data and resulting characterization of cooking area and personal PM2.5 exposures in multiple rural communities from 10 countries will better inform exposure assessment as well as future epidemiologic analyses assessing the relationships between quantitative estimates of chronic HAP exposure with adult mortality and incident cardiovascular and respiratory disease. This will provide refined and more accurate exposure estimates in global CVD related exposure-response analyses.

Pregnancy outcomes and ethanol cook stove intervention: A randomized-controlled trial in Ibadan, Nigeria

BACKGROUND

Household air pollution (HAP) exposure has been linked to adverse pregnancy outcomes.

OBJECTIVES

A randomized controlled trial was undertaken in Ibadan, Nigeria to determine the impact of cooking with ethanol on pregnancy outcomes.

METHODS

Three-hundred-twenty-four pregnant women were randomized to either the control (continued cooking using kerosene/firewood stove, n=162) or intervention group (received ethanol stove, n=162). Primary outcome variables were birthweight, preterm delivery, intrauterine growth restriction (IUGR), and occurrence of miscarriage/stillbirth.

RESULTS

Mean birthweights for ethanol and controls were 3076 and 2988g, respectively; the difference, 88g, (95% confidence interval: -18g to 194g), was not statistically significant (p=0.10). After adjusting for covariates, the difference reached significance (p=0.020). Rates of preterm delivery were 6.7% (ethanol) and 11.0% (control), (p=0.22). Number of miscarriages was 1(ethanol) vs. 4 (control) and stillbirths was 3 (ethanol) vs. 7 (control) (both non-significant). Average gestational age at delivery was significantly (p=0.015) higher in ethanol-users (39.2weeks) compared to controls (38.2weeks). Perinatal mortality (stillbirths and neonatal deaths) was twice as high in controls compared to ethanol-users (7.9% vs. 3.9%; p=0.045, after adjustment for covariates). We did not detect significant differences in exposure levels between the two treatment arms, perhaps due to large seasonal effects and high ambient air pollution levels.

CONCLUSIONS

Transition from traditional biomass/kerosene fuel to ethanol reduced adverse pregnancy outcomes. However, the difference in birthweight was statistically significant only after covariate adjustment and the other significant differences were in tertiary endpoints. Our results are suggestive of a beneficial effect of ethanol use. Larger trials are required to validate these findings.

Elevated blood pressure and household solid fuel use in premenopausal women: Analysis of 12 Demographic and Health Surveys (DHS) from 10 countries

BACKGROUND

Approximately three billion people are exposed to household air pollution (HAP) from solid fuel cookstoves. Studies from single settings have linked HAP with elevated blood pressure (BP), but no evidence exists from multi-country analyses.

OBJECTIVES

Using nationally representative and internationally comparable data, we examined the association between solid fuel use and BP in 77,605 largely premenopausal women (aged 15-49) from ten resource-poor countries.

METHODS

We obtained data on systolic and diastolic BP, self-reported primary cooking fuel, health and socio-demographic characteristics from 12 Demographic and Health Surveys conducted in Albania, Armenia, Azerbaijan, Bangladesh, Benin, Ghana, Kyrgyzstan, Lesotho, Namibia, and Peru. We estimated associations between history of fuel use [solid fuel (coal or biomass) versus clean fuel (electricity or gas)] with systolic and diastolic BP and hypertension using a meta-analytical approach.

RESULTS

Overall, the country-level mean systolic and diastolic BP were 117 (range: 111-127) and 74 (71-83) mmHg, respectively. The country-level mean age of the women was 30.8 years (range: 28.4-32.9). The prevalence of solid fuel use was 46.0% (range: 4.1-95.8). In adjusted, pooled analyses, primary use of solid fuel was associated with 0.58mmHg higher systolic BP (95% CI: 0.23, 0.93) as compared to primary use of clean fuel. The pooled estimates for diastolic BP and pulse pressure were also positive, but the confidence intervals contained zero. The pooled odds of hypertension was [OR = 1.07 (95% CI: 0.99, 1.16)], an effect that was driven by rural participants for whom solid fuel use was associated with a 16% greater odds of hypertension [OR = 1.16 (95% CI: 1.01, 1.35)].

CONCLUSIONS

Cooking with solid fuels was associated with small increases in BP and odds of hypertension. Use of cleaner fuels like gas or electricity may reduce cardiovascular risk in developing countries, particularly among rural residents.