BACKGROUND: Dust storms and their impacts on health are becoming a major public health issue. The current study examines the health impacts of dust storms around the world to provide an overview of this issue.
METHOD: In this systematic review, 140 relevant and authoritative English articles on the impacts of dust storms on health (up to September 2019) were identified and extracted from 28 968 articles using valid keywords from various databases (PubMed, WOS, EMBASE, and Scopus) and multiple screening steps. Selected papers were then qualitatively examined and evaluated. Evaluation results were summarized using an Extraction Table.
RESULTS: The results of the study are divided into two parts: short and long-term impacts of dust storms. Short-term impacts include mortality, visitation, emergency medical dispatch, hospitalization, increased symptoms, and decreased pulmonary function. Long-term impacts include pregnancy, cognitive difficulties, and birth problems. Additionally, this study shows that dust storms have devastating impacts on health, affecting cardiovascular and respiratory health in particular.
CONCLUSION: The findings of this study show that dust storms have significant public health impacts. More attention should be paid to these natural hazards to prepare for, respond to, and mitigate these hazardous events to reduce their negative health impacts.
Registration: PROSPERO registration number CRD42018093325
Introduction
Dust storms are natural hazards and the most common sources of natural particles, including very small materials, potential allergens, and pollutants.1–5 Depending on the nature of the source of the dust, these materials and substances may include, quartz, silicon dioxide, oxides of magnesium, calcium, iron, and aluminum6,7 and sometimes a range of organic matter, anthropogenic pollutants, and salts.8 Dust storms carry millions of tons of soil into the air each year from thousands of kilometers away. They can last a few hours or a few days1–5 and distribute a large number of small particles in the air,9,10 increasing the amount of particles above the allowable threshold for human health.11,12 During a dust storm event, the concentration of PM10 (particles with an aerodynamic diameter <10 µm) and PM2.5 (particles with an aerodynamic diameter <2.5 µm) particles are often higher than the normal thresholds recommended by the World Health Organization (PM2.5: 10 µg/m3 annual mean, 25 µg/m3 24-hour mean. PM10: 20 µg/m3 annual mean, 50 µg/m3 24-hour mean).8,13 It can also exceed 6000 µg/m3 in seriously strong dust storms.14 According to the Huffman Classification of dust PM10 range (µg/ m3), in dusty air, light dust storm, dust storm, strong dust storm, and serious strong dust storm days, levels can be between 50 to 200, 200 to 500, 500 to 2000, 2000 to 5000, and >5000, respectively.15
Dust storms are occurring increasingly frequently in many desert areas and arid regions around the world,3 causing extensive damage and emergencies each year.3,16–18 Therefore, dust storms have attracted increasing attention in recent years.16,17,19 Researchers have demonstrated how dust storms affect various aspects of human life.19 The particles in dust storms affect weather conditions, agricultural production, human health, and the ecosystem.20,21 Evidence suggests that mineral aerosols affect cloud formation and precipitation and can reduce the acidity of precipitation.22 Moreover, a high density and diversity of bacteria and plant pollens have been observed during dust storms.23 In addition to endangering the ecosystem, dust storms have direct and indirect impacts on public health and human health.8,20,21,24 Due to their small sizes, almost all dust storm particles, that is, airborne particles (PM) can enter the respiratory tract25; larger particles are often deposited in the upper respiratory tract (nasopharyngeal region, tracheobronchial region), while smaller particles can enter deep lung tissue.26,27 The physical, biological, and chemical properties of these particles can cause disorders in the health of the body,8,24,26 and in addition to the respiratory tract, can damage other systems of the body, including the cerebral, cardiovascular, skin,8,24,26 blood, and immune systems.28,29
Research has indicated that exposure to dust particles, which can remain in the air from hours to days,24 can result in other problems like conjunctivitis, meningitis, and valley fever.24,26,30 In rare cases, it can even lead to death.26,31 Evidence further suggests that frequent exposure to dust storms can lead to increased adverse health effects24,32–37 in people of almost all age groups and genders.3,38,39 People with a history of diabetes, hypertension, cerebrovascular, or pulmonary disease are also at higher risk.40 Many epidemiological studies have determined the health effects of dust storms by comparing outcomes during dust storm periods with outcomes during non-dust storm periods41–43 and by assessing the correlation between dust storms or PM10 exposure and health outcomes.32,44 Many researcher have acknowledged the existence of a significant association between dust exposure and increased morbidity or mortality, but there is no consensus in this regard to date.45 Pérez et al. stated that increased PM during dust storms caused a significant increase in mortality rate in Barcelona.46 Chen et al.,47 Kashima et al.,48 and Delangizan49 also noted that increased PM10 levels during Asian dust storms increased cardiovascular mortality. Some studies have reported that Middle Eastern dust storms can affect inflammation and coagulation markers in young adults,28,29 have adverse effects on pulmonary function,50 and increase the number of asthma patients.51–52 Conversely, some studies have either ruled out the possibility of an increase in mortality or hospitalizations of patients due to dust storm exposure or do not consider the increase to be significant.43,53–55 For example, in studies conducted in Italy,53 Greece,54 Kuwait,43 and Taipei,55 researchers found no significant relationship between dust storms and increased risk of death. Bell,56 Ueda,57 and Min58 also found that dust storms did not significantly increase hospitalizations of asthmatic patients or asthma attacks in Taipei and Japan.56
There are mixed results and a lack of accurate and up-to-date classified data about the health impacts of dust storms on humans around the world. Moreover, the causes of dust storm-related health problems are not yet completely understood.59 Given the importance of the impact of dust storms on human health as well as the increasing evidence of recurring and negative impacts of these storms, and because of the lack of systematic review studies, the current study conducted an extensive review of the current literature on the impacts of dust storms on human health.
Materials and Methods
This systematic review of scientific resources identified articles related to dust storms and related human health outcomes published up to 30 September 2019. PubMed, EMBASE, Scopus, and ISI WoS (Web of Science) databases were searched for articles published in relevant journals from the 28th to the 30th of October, 2019. All peer-reviewed articles from English language journals were discovered in the primary search stage. Citations and references of all relevant articles were examined and searched manually to ensure that all relevant articles were included. The primary search used the following Medical Subject Headings (MeSH terms) and keywords: Dust* OR Kosa OR Yellow sand OR Arabian Sand OR Dust Storms AND Mortality OR Disease* OR Morbidity OR Admission* OR Health* OR “Adverse affect” OR affect*.
Executive limitations: The main limitations of the current study were the lack of access to all required databases as well as the lack of access to the full text of some articles which should be obtained by correspondence with the authors of those articles. To resolve this problem, the researchers resorted to using resources from various universities inside and outside the country.
Inclusion criteria: All studies that had the full text available, that used appropriate methods and data, and that calculated the impacts of dust storms on health (eg, odds ratio, relative risk, rate ratio, regression coefficient, percentage change, excess risk, etc. in health indicators following dust storms); those in which dust storm was a major problem and those in which health indicators were analyzed were included in this study without restrictions on the publication date.
Exclusion criteria: Non-English articles, non-research letters to editors, review studies, case reports, case series, specialized articles about microorganisms, animal experiments, in vitro studies, and dust from volcanic or manmade sources like stone mines or stone and cement factories were excluded.
Data collection process: The current study followed the PRISMA guidelines (PRISMA Flow Diagram). EndNote software was used to manage the retrieved articles. After all articles were entered into the software, duplicates were identified and removed. Then, 2 researchers screened the remaining articles separately based on the inclusion and exclusion criteria by reading the titles, abstracts, and keywords. After removing unrelated papers, the full text of the remaining articles were found and attached, and the quality of each paper in a standard format related to the type of study was assessed separately by the 2 researchers using JBI’s critical appraisal tools. In cases of disagreement between the researchers, the third researcher helped to select the most relevant items.
Data extraction: The information required for this study was extracted using a checklist previously reviewed and prepared, which included all the characteristics of the selected articles, including type of article, publication year, first author’s name, location of study, study design/methodology, health effects, PM fraction, and age/gender.
Risk of bias (quality) assessment: For quality assessment of the included papers, the Critical Appraisal Skills Program (CASP) checklist was used. The assessment was conducted by 3 independent reviewers. Discrepancies were resolved by 2 other reviewers.
Results
Search results
Out of a total of 35 712 articles searched, 140 articles met the inclusion criteria (Figure 1). The majority of them were related to ecological, case crossover, and prospective studies; other studies included descriptive, retrospective, and Panel studies and 1 research letter (Table 1).
Table 1.
Published studies on adverse health effects of dust storms.
The current results showed that most data analyses investigated the effects of dust storms on health and used the generalized additive model (GAM) with nonlinear Poisson regression method to analyze the data in ecological and case-crossover studies.
Furthermore, most studies on the impact of dust storms on health were performed within the last decade (Chart 1).
Most health and dust storm studies included in this study were undertaken in Japan (n = 29; 20.71%), Taiwan (n = 25; 17.85%), Korea (n = 16; 11.42%), China (n = 10; 7.14%), Spain (n = 9; 6.42%), and Iran (n = 8; 5.71%), respectively (Figure 2).
In this review, the following adverse health effects of dust storms emerged as important:
Non-accidental death (mortality due to respiratory, cardiovascular, or cerebrovascular disease);
Emergency medical dispatch, hospitalization or admission, and hospital visits due to respiratory or cardiovascular diseases;
Daily symptoms such as nasopharyngeal, skin, or ocular symptoms, and decreased pulmonary function Table 1).
The current analysis indicated that the effects of dust storms on health can be divided into 2 general sections: short- and long-term effects. Short-term effects have been defined herein as human health problems that occurred during or immediately after a dust storm, and long-term effects are defined as human health problems that occurred after a long exposure to several periods of dust storms.
Short-Term Health Effects
The short-term effects included all-cause mortality, emergency dispatch or air medical retrieval service, hospitalization or admission, healthcare visits, daily symptoms, decreased pulmonary function, and other problems.
Mortality
Thirty-three articles from almost all regions discussed mortality due to dust storms by means of different health problems, such as increased total non-accidental deaths,3,38,39,41,46,53–55,68–82 cardiovascular deaths,3,38,39,48,50,53,70,74,77,82–85 mortality due to acute coronary syndrome (ACS),3,70,81,86 and respiratory mortality.48,53,55,77,87 Some studies reported, however, that the number of cases was not increased significantly for all-causes,43,88 respiratory,38,43 cardiovascular,43 or cerebrovascular mortality.69 Neophytou et al.82 in Nicosia reported that associations for respiratory mortality was −0.79 (−4.69, 3.28) on dust storm days. Lee et al.55 in Taipei found that dust storms have a protective effect on non-accidental deaths, respiratory deaths, and death in people >65 years of age.
Emergency dispatch or air medical retrieval service
Four articles discussed the emergency medical services required due to dust storm, focusing on different health problems. This review observed an increased relative risk of all medical emergency dispatches and a significant increase in cardiovascular dispatches,42 increased daily ambulance calls due to respiratory, cardiovascular, and all causes,89 and an increase in emergency dispatches due to cardiovascular, respiratory, injury and all causes.90
Hospitalization or admission
Sixty-two articles from almost all regions discussed hospitalization or admission due to dust storms by means of different health problems or diseases. The results indicated that in many studies, dust storms were associated with an increased risk of hospital admission due to cardiovascular, cerebrovascular, and respiratory diseases, among others.
Cardiovascular disease (CVD) hospitalizations or admissions
In relation to cardiovascular diseases and the effect of dust storms, 17 studies stated that dust storms can increase: (1) the risk of circulatory outpatients and inpatients91; (2) odds ratio of admission and hospitalization due to congestive cardiac failure86 and acute coronary syndrome2,86; (3) effects on cardiac diseases92; (4) risk of CVD hospitalization or admission40,78,93–97; (5) emergency admissions for CVD92; (6) the impacts on acute myocardial infarction (AMI)98–100; (7) emergency hospital admissions for ischemic heart diseases (IHD)101; (8) hospital admissions for congestive heart failure (CHF)102; and (9) inpatient hospitalization due to cardiac failure.86 However, some studies reported non-significant results, such as no association between dust storms and out-of-hospital cardiac arrests103 and no significant changes in admissions concerning cardiovascular syndromes.104 Also, some reported no significant association between increased dust particles and angina.50 Bennett et al.105 reported that the dust storms were not associated with an excess of CVD hospitalizations.
Respiratory disease hospitalizations or admissions
Regarding respiratory diseases related to dust storms, 35 studies stated that dust storms can increase the risk of respiratory outpatients,91 respiratory disease hospitalizations or admissions,11,40,43,51,57,78,92,93,96,104,106–114 cases of bronchial asthma,93 asthma-related hospitalizations or admissions,51,57,112–116 cases of aggravated asthma disease,117,118 daily pneumonia admissions,119,120 hospital admissions for chronic obstructive pulmonary disease (COPD),50,87,121–123 emergency hospital admissions for COPD,124 emergency admissions for respiratory diseases,92 admitted patients suffering from respiratory infection,50 and the prevalence of chronic bronchitis, cough, and rhinitis.125
Surprisingly, several studies did not find any link between dust storms and negative health outcomes, such as no significant effect on asthma exacerbations in Riyadh,126 no significant change in the risk of emergency admission in dust events,127 and no association between sandstorms and risk of hospital admission for asthma or pneumonia patients.56 Moreover, some studies reported no statistically significant relationship between increased dust levels and pulmonary function, allergic disease, emergency admission, or drug use128; no significant relationship between increased risk of chronic obstructive pulmonary disease, asthma, and angina and increased concentration of dust storms50,129; And no excess risk of respiratory hospitalizations.105 Only two studies found a decrease in respiratory problems after dust storms, like a decreased risk of respiratory inpatients in Taklimakan Desert,91 and a lower rate of respiration problems among children in areas with higher levels of dust deposition as reported by Wiggs et al.130
Cerebrovascular diseases hospitalizations or admissions
Regarding the correlation between cerebrovascular diseases and dust storms, 6 studies stated that dust storms can increase the risk of cerebrovascular diseases,40,92 the incidence of athero-thrombotic brain infarction,131 stroke admission rates,132 hospital admissions for epilepsy problems, cerebral ischemic attacks, and various types of headaches,133 and daily intracerebral hemorrhagic (ICH) stroke admissions.134 Bell et al.,56 however, reported that sandstorms have no significant relationship with the risk of admission to cerebrovascular patients. Moreover, Yang et al.134 stated that there is no significant association between the risk of ischemic stroke and dust storms.
Other diseases hospitalizations or admissions
Aili et al.91 reported that the risk of digestion outpatients and inpatients, gynecology outpatients, pediatrics outpatients and inpatients, and ENT outpatients and inpatients was increased during dust storms. Chan et al.135 also stated that dust storms were significantly associated with diabetes admissions for females. Furthermore, Ko et al.137 stated that dust storms can increase the risk of conjunctivitis.
Healthcare visits
Nineteen articles studied the daily number of healthcare visits due to dust storms for different health problems. Except for 1 article, all others reported that dust storms are associated with an increased daily number of healthcare visits due to asthma-related health problems137–141 cardiac, respiratory, and stroke diagnoses,142 emergency healthcare visits for IHD, CVD, and COPD,143 conjunctivitis clinic visits,144,145 children clinic visits for respiratory problems,139,146 healthcare visits for respiratory diseases,52,139,146,147 healthcare visits for all causes, circulatory, and respiratory diseases,148 and for cardiovascular and respiratory problems.149,150 Lorentzou et al.122 also reported a large increase in emergency visits related to dyspnea during dust storms; however, no clinically significant increase was observed in the total number of emergency visits.
Daily symptoms
Twenty articles studied the daily symptoms resulting from dust storms. In 2 studies, Higashi et al.151,152 showed the effects of Kosa on cough. Otani et al.153 found that the scores for symptoms (nasopharyngeal, ocular, respiratory, and skin) were significantly higher when related to dust storms. Onishi et al.154 reported that all symptoms (nasal, ocular, respiratory, throat, and skin) increased after exposure to dust storms. Mu et al.35 also reported that an increased risk of eye lacrimation occurrence is associated with dust events. Majbauddin et al.155 reported a positive correlation between the increased concentration of dust storms and ocular, nasal, and skin symptoms. Similarly Meo et al.156 observed that sandstorms can increase complaints of sleep and psychological disturbances as well as other problems like eye irritation, cough, wheeze, headache, and runny nose.
Pulmonary function
Nine articles discussed pulmonary function in relation to dust storms, and the evidence is conflicting. Kurai et al.,157 Watanabe et al.,158,159 Yoo et al.160 and Watanabe et al.161 all found that dust storms have a significant, negative effect on pulmonary function. Other studies, including Hong et al.,162 Watanabe et al.159 and Park et al.163 found no significant relationship between pulmonary function and dust storms. Kanatani et al. found that dust storms can increase the risk of allergic symptoms in pregnant women.164 Yoo et al.,160 reported a significant increase in respiratory symptoms during dust storms, and Watanabe et al.159 reported that sand and dust storms are significantly associated with respiratory symptoms. Moreover, Park et al.163 reported a relationship between nighttime symptoms and particular matter levels during dust storms. Watanabe et al.165 also stated that dust storms worsen respiratory symptoms in asthmatic patients, but some studies like O’Hara et al.166 reported that pulmonary function was better in children who were more exposed to dust storms than in those with low exposure to dust.
Other impacts
Some articles explored the relationship of dust storms with road traffic accidents, risk of suicide, placental abruption, and health-related quality of life. Islam et al.167 found that sandstorms and the number of vehicles were significantly responsible for road traffic accidents. Soy et al.106 reported that dust storms can have adverse effects on the quality of life of patients with asthma and allergies. Mu et al.117 reported that dust storms can decrease health-related quality of life in everyone exposed to them. Lee et al.168 reported that exposure to dust storms was associated with an increased risk of suicide (13.1%; p = 0.002).
Long-Term Health Effects
Six articles discussed the long-term adverse health effects caused by dust storms by means of different outcomes, like reduced birth weight, baby’s birth weight <2.5 Kg, gestation/gestational age >37 weeks and premature birth,32 and decreased cognitive function in children.33 Preterm births34 were correlated with Valley fever incidences36 and increased spring measles incidence.44 Only one article was observed to indicate no significant effect of desert dust storms on pregnancy consequences.169
Discussion
In this study, the majority of valid scientific databases were searched to find articles and studies related to the health effects of dust storms. Other similar studies have used fewer scientific databases in their search. The final number of articles included in this study is higher than that in all previous studies.24,26 The current results showed that the model most used to evaluate the health effects of dust storms was the GAM method. In this regards, Ramsay 2003 stated, “Such methods eliminate the need to specify a parametric form for secular trends and allow a greater degree of robustness against model misspecification.”170 The results of the current study also showed that most dust storm studies have been carried out in Japan, Taiwan, and South Korea, which may be due to the large number of dust storms occurring in Northeast Asia. This area is exposed to yellow dust storms caused by strong winds on the Loos Plateau and the Gobi and Talkmanistan Deserts, and as yellow dust storms became so prevalent in that area within the last two decades, researchers in the area have studied their health effects.152,171
The review results showed that most studies around the world confirm the adverse effects of dust storms on health. The relevant health problems were categorized into long-term and short-term impacts. Few studies were found that focused on the long-term impacts of dust storms on human and public health; however, those studies found showed that dust storms may increase the risks for problems in pregnancy and childbirth, children’s cognitive problems, and infectious diseases. In line with the risks of birth as well as cognitive problems in children, animal studies have shown that the fetal brain is easily exposed to air pollutants, because in the human fetus, the blood-brain barrier has not yet developed; therefore, the fetal brain is exposed to pollutants and is sensitive to blood changes caused by them.1–3 Furthermore, new research on humans has shown that environmental pollutants can possibly create inflammation, oxidative stress, and vascular damage to the fetal brain after passing through the placenta.4–7 Researchers have studied the effects of PM from dust storms on maternal health during pregnancy and birth problems, and they refer to variations in maternal host-defense mechanisms, maternal-placental exchanges, oxidative pathways, and endocrine dysfunction as possible causes of these problems.8 Ultimately, the evidence from infectious diseases shows that pathogenic microorganisms are abundant in dust storms,9 and dust storms can spread these microorganisms over a large area. Therefore, it can be argued that microorganisms that are suspended or attached to dust particles can be transferred from one part to another and may induce infectious diseases at various destinations by dust storms.10,11 More studies have been conducted on the short-term impacts of dust storms. The majority of these studies indicate the effects of dust storms on important body systems, including the cardiovascular, respiratory and cerebral systems, which lead to the increased incidence of clinical symptoms and severity of symptoms; increased emergency visits, ambulance dispatches, and hospitalizations or admissions; decreased lung capacity; and eventually death.
Most studies show that dust storms increase the risk of cardiovascular problems, the number of cardiovascular emergency medical dispatches, cardiovascular visits, the number of cardiovascular symptoms among patients referring to the hospital, cardiovascular admissions or hospitalizations, and deaths due to cardiovascular disease. Although the exact mechanism for the effects of dust storms on heart problems has not yet been determined,12 studies show that fine particles in dust storms can enter lung tissue and the bloodstream through chemical interactions,13 causing a thrombolytic and inflammatory process and the secretion of cytokines in the body.14,15 Moreover, the toxicity of some of these substances in the body reduces the contractibility of the heart, increases vasoconstriction, and increases blood pressure.14,–20 Therefore, the above cases may confirm the effects of dust storms on cardiovascular health.
The results of the current study showed that according to most articles, the risk of death following respiratory problems; the risk of admission and hospitalization due to respiratory disorders like pneumonia, asthma, and chronic obstructive pulmonary disease and other respiratory problems; respiratory symptoms; and healthcare visits associated with dust storms have increased. Other results showed that dust storms reduce lung capacity and function.
The results of studies have shown that 1 mechanism of dust storms is that small particulates in dust storms are likely to trigger an innate immune response by T-lymphocytes in the body and respiratory system, which can cause chronic inflammation and advanced COPD.22–25 PM can also play a significant role in respiratory oxidative stress, increase pulmonary inflammation, increase atopic responses and Immunoglobulin E production in respiratory problems (especially asthma), and exacerbate symptoms.26 Another mechanism that may cause respiratory illnesses following a dust storm is the presence of pathogens such as microorganisms and fungi37 as well as some minerals such as silica in some of these storms. These particles enter the airway after dust storms and exacerbate the disease or cause respiratory problems in people at risk.22 For example, neutrophilic pulmonary inflammation may be caused by bacterial and fungal debris in dust particles to which individuals are exposed. Some of this debris includes lipopolysaccharide (LPS), a cell wall glycolipid of gram-negative bacteria, and β-glucan, which is the most important constituent of the fungal wall. Both of them are clearly observed in dust storms along with dust particles.22,38,39 Although the precise mechanisms for pneumonia are yet to be found, some studies have suggested that high amounts of particles in dust storms can cause oxidative stress, induce inflammation, increase blood clotting, disrupt defense cells, and cause immune system fluctuations, ultimately inducing alveolar inflammation and exacerbating lung disease.3,40,41
In 2009, Calderon Garosia stated that pollutants in dust storms can cause problems such as cardiovascular, respiratory, liver, and skin toxicity through systemic inflammation42 and may induce a pre-inflammatory systemic response in cytokines, which may disrupt the HPA axis and ultimately cause mood swings and psychological problems, including suicidal thoughts.42–44 In addition, chemical components found in dust storms can enter the brain through the mucosa and olfactory system.42 After entering the nervous system, they may accumulate in the anterior cortex of the brain and cause problems in emotional regulation and impulse control.45 Some researchers also suggest that some mechanisms are associated with placental abruption due to dust storms, such as microbiological and chemical substances in dust storms that induce an inflammatory response in the body.46,47 Inflammation and ischemia increase the risk of decidual bleeding, followed by hematoma formation and placental abruption.48,49 There is also some speculation that as lipopolysaccharide has been found in Asian dust storms, the activity of this endotoxin in the body may lead to premature birth due to chorioamnionitis, which is also associated with placental abruption.50,51
The current review shows that some studies have also linked dust storms with some other health problems, such as increased road accidents, increased suicide risk, increased premature placental abruption, ocular problems, and reduced quality of life. These issues could be further studied in areas prone to dust storms. Islam11 stated that the reduced field of vision, the lack of dust storm warning systems, and traffic due to dust and sand storms can be considered as reasons for the recent increase in number of road accidents. Dust particulates in these storms can also cause acute ocular problems such as tears and conjunctivitis in people due to their inflammatory effects.52 I In terms of the quality of life, Mu53 stated that an increase in health problems and clinical symptoms that are associated with allergens and ocular problems such as conjunctivitis dust storms reduce the quality of life.
Despite all the significant effects of dust storms on health, this review found some studies that presented no significant association between dust storms and health problems including all-cause and respiratory mortality,43,88 cardiovascular,103–105 cerebral,134 and respiratory problems.127–129 Moreover, some studies reported that dust storms may have a protective effect against non-accidental and respiratory death55 and other pulmonary problems.91,130,166
However, O’Hara stated that although the lack of matching of exposed and non-exposed groups in nutritional, economic, and social problems may play a role in the insignificance of the effects of dust storms on health, the chemical and physical nature of the particles in dust storms are of more importance than their total amounts.55,166 Differences in the chemical and physical nature of particulate matters may cause different health outcomes in varying regions.55 Another reason for the difference may be the use of rapid early warning systems in some countries. Lee justified the protective effects of dust storms on death, stating that in Taipei, a complex rapid early warning system is used for dust storms, and the use of this system may produce protective effects of dust storms on mortality.55 Finally, almost all of the reviewed articles reported on a group of diseases or deaths that were studied, while dust storms may not affect all diseases and deaths.22 This may be another reason for these differing results.
Conclusion
This systematic review presents an accurate and comprehensive study of all aspects of human health in relation to dust storms. For the first time in the world, this in-depth and unique study was conducted to summarize the short-term and long-term effects of dust storms. To date, this amount of reliable data on this issue has never been investigated. As the results showed, despite the short-term effects dust storms have on human health (including adverse effects on the respiratory, skin, ocular, cardiovascular, and cerebral systems as well as increased mortality and morbidity) that may occur immediately after each dust storm, the frequency of dust storms in an area is also an important factor. In addition to exacerbating short-term health effects, they may also cause long-term health effects, which may include health problems for pregnant mothers, fetuses and infants, in the cognitive function of children, and increases in some infectious diseases. Therefore, as climate change and drought have caused this phenomenon to endanger the lives of many people around the world, and as the health and well-being of people is a main priority in any country, it is recommended that more studies be conducted in countries exposed to dust storms to examine the health effects of these storms in order to better understand the mechanisms through which dust storms impact human and public health and to develop a better strategy for preparing for, preventing, and mitigating the destructive effects of these storms.
Acknowledgements
Many thanks to Institute for School of public health and Environmental Research (IER) of Tehran University of Medical Sciences (TUMS), for supported current study.
Author Contributions “HA and AOT designed the study; HA collected the data; HA and AOT analyzed and interpreted the data. HA, AOT, A Ardalan, MA, MY, CS and A Asgary prepared the manuscript. All authors contributed to the drafting and final review of the manuscript. The author (s) read and approved the final manuscript.”
Ethical Approval Current study was approved by the Ethics Committee of Tehran University of Medical Sciences (TUMS) Ethics Code: IR.TUMS.SPH.REC.1399.004, and also all methods were performed in accordance with the relevant guidelines and regulations.