Burden of dust storms on years of life lost in Seoul, South Korea: A distributed lag analysis

Although dust storms have been associated with adverse health outcomes, studies on the burden of dust storms on deaths are limited. As global warming has induced significant climate changes in recent decades, which have accelerated desertification worldwide, it is necessary to evaluate the burden of dust storm-induced premature mortality using a critical measure of disease burden, such as the years of life lost (YLL). The YLL attributable to dust storms have not been examined to date. This study investigated the association between Asian dust storms (ADS) and the YLL in Seoul, South Korea, during 2002-2013. We conducted a time-series study using a generalized additive model assuming a Gaussian distribution and applied a distributed lag model with a maximum lag of 5 days to investigate the delayed and cumulative effects of ADS on the YLL. We also conducted stratified analyses using the cause of death (respiratory and cardiovascular diseases) and sociodemographic status (sex, age, education level, occupation, and marital status). During the study period, 108 ADS events occurred, and the average daily YLL was 1511 years due to non-accidental causes. The cumulative ADS exposure over the 6-day lag period was associated with a significant increase of 104.7 (95% CI, 31.0-178.5 years) and 34.4 years (4.0-64.7 years) in the YLL due to non-accidental causes and cardiovascular mortality, respectively. Sociodemographic analyses revealed associations between ADS exposure and the YLL in males, both <65 and ≥ 65 years old, those with middle-level education, and the unemployed, unmarried, and widowed (26.5-83.8 years). This study provides new evidence suggesting that exposure to dust storms significantly increases the YLL. Our findings suggest that dust storms are a critical environmental risk affecting premature mortality. These results could contribute to the establishment of public health policies aimed at managing dust storm exposure and reducing premature deaths.

Holocene dust storm variations over northern China: transition from a natural forcing to an anthropogenic forcing

Asian dust storms have long been a major environmental concern in China, affecting the lives of about one billion people. However, it is unclear whether the mechanisms responsible for Asian dust storms during the Holocene varied on different timescales, and thus it is unclear whether there was a shift from a natural forcing to an anthropogenic forcing of dust storms. We reconstructed a high-resolution Holocene record of dust storms from the sediments of an undisturbed alpine lake on the Chinese Loess Plateau. We found that Asian dust storm activity generally increased during the Holocene, with the largest fluctuations occurring during the past 2000 years. The increase in dust storm activity was in contrast to the decrease in East Asian winter monsoon (EAWM) intensity during the Holocene, indicating that the EAWM played a limited role in modulating dust storms. By contrast, the increase in dust storms corresponded to a decrease in EASM precipitation. This demonstrates that EASM precipitation was the dominant control of dust storm activity on a millennial timescale, because decreased EASM precipitation expanded the desert area and thus increased the dust storm activity. The increasing intensity of human activity in the region since the Bronze Age resulted in an acceleration of dust storm activity against the background of decreased EASM precipitation. As human disturbance continued to intensify, beginning at least at ~2 cal ka BP, increased dust storms were closely linked to increasing human populations in the dust source regions, and there is a strong temporal coherence between increased dust storms and higher EASM precipitation. This was completely different from when natural processes are dominant. During that period, fewer dust storms occurred during periods of a strengthened EASM. Therefore, there was a shift from a natural forcing to an anthropogenic forcing of dust storms on a multi-decadal to centennial timescale, and was a mode in which "human activity overtook the EASM as the dominant control of the Earth surface system".

The effect of air dust pollution on semen quality and sperm parameters among infertile men in west of Iran

Background: Pollutants during haze and Asian dust storms are transported out of the Asian continent, affecting the regional climate and the hydrological and biogeochemical cycles. Nonetheless, no specific studies evaluated the dust particles influence on semen quality in a specific geographical area.Objective: In this article, we investigated the effect of dust particles on semen quality and sperm parameters among infertile men.Methods: A descriptive-analytic study was conducted among 850 infertile men between 2011 and 2015 years. Semen quality was assessed according to the WHO 2010 guidelines, including sperm concentration, progressive motility, and morphology. Four-year average dust particle concentrations were estimated at each participant's address using the Air Pollution Monitoring Station affiliated with the Department of Environment of Kermanshah city were gathered.Results: Dust particle levels were highest in the summer months, in Kermanshah province. Our results show that, dust pollution was found to be significantly negatively correlated with sperm morphology and sperm concentration before and after lab-processing, but sperm progressive motility is low sensitive to dust particles.Conclusions: Our findings showed that exposures to dust particle may influence sperm quantity in infertile men, consistent with the knowledge that sperm morphology and concentration are the most sensitive parameters of dust pollution.

Association between dust storm occurrence and risk of suicide: Case-crossover analysis of the Korean national death database

BACKGROUND

Asian dust storms (ADSs) have been associated with adverse health outcomes, including respiratory and cardiovascular diseases. Considering the increasing global desertification driven by climate change, it is necessary to assess dust storm-related adverse health effects for establishing appropriate public health interventions. Recent studies have found that ambient air pollution has negative effects on mental health including cognitive disorders, depression, and suicide. However, these studies mostly focused on traditional anthropogenic pollutants from traffic exhaust or fossil fuel power plants; the association between dust storms and suicidal death is yet to be determined.

OBJECTIVE

To assess the association between ADSs and suicide risk in Seoul, South Korea from 2002 to 2015.

METHODS

To determine whether increased risk of suicide is associated with occurrence of ADSs, we performed a time-stratified case-crossover study that linked the national death statistics database with ADS occurrence data from the Korea Meteorology Administration. Exposure to ADSs was compared between the day of suicide and control days, matched to the day of the week, month, and year. We further examined whether the effect of ADSs on suicide risk differed according to ADS duration and intensity.

RESULTS

Over the 14-year period, 30,704 people died by suicide and 133 ADSs were reported. Of these, 55 ADSs lasted over 2 days (long-duration ADSs), and 67 ADSs had higher levels of particulate matter < 10 μm in diameter (PM₁₀) that exceeded the 50th percentile value over the total 133 ADS days (high-intensity ADSs). Exposure to ADS was associated with a 13.1% (95% confidence interval [CI], 4.5-22.4; P = .002) increase in suicide risk on the day of ADS occurrence. Long-duration and high-intensity ADSs were associated with a 19.8% (95% CI, 6.5-34.7; P = .003) and 17.0% (95% CI, 5.2-30.0; P = .004) increase in suicide risk, respectively. These associations remained robust after adjusting for local air pollution levels and meteorological factors. However, this association was not replicated in the unconstrained distributed lag model which revealed inferior goodness-of-fit to our data.

CONCLUSIONS

Exposure to ADSs was associated with an increased risk of suicide, especially on the same day. This study provides novel evidence of a relationship between ADSs and suicide. These findings could help in establishing public health interventions for suicide prevention as well as in establishing dust storm warning systems. Future studies are warranted to confirm if our findings are replicable and to elucidate the underlying mechanisms.

Enhanced health risks from exposure to environmentally persistent free radicals and the oxidative stress of PM2.5 from Asian dust storms in Erenhot, Zhangbei and Jinan, China

Asian dust storms can increase the level of atmospheric pollution over regions downwind of dust storms and may have adverse health effects on residents along the sandstorm transmission route. This study was the first to report the concentration levels, properties and possible sources of environmentally persistent free radicals (EPFRs) and oxidative potential in atmospheric PM_2.5 at the three sites of Erenhot, Zhangbei, and Jinan along the transport route of Asian dust storms during the occurrence of Asian dust storms in the spring of 2016. Under non-sandstorm weather conditions, the average EPFR concentrations at the three sites were Zhangbei>Jinan>Erenhot, while the PM-induced oxidative potential levels were Erenhot>Jinan>Zhangbei. The PM_2.5 concentration increased significantly during dust storm events, and the total atmospheric concentration of EPFRs (spins/m³) and total oxidation potential (a.u./m³) of PM_2.5 simultaneously increased. However, the EPFR concentration in PM_2.5 (spins/g) and the unit mass of the PM oxidation potential (a.u./g) were significantly reduced. Electron paramagnetic resonance analysis combined with backward trajectory analysis and MODIS products showed that Asian dust storms can carry EPFRs over long distances. Correlation analysis showed that the atmospheric concentrations of EPFRs were positively correlated with elemental carbon (EC) for the Zhangbei and Jinan samples but were not significantly correlated with EC for the Erenhot samples, indicating that combustion may be an important source of EPFRs for the Zhangbei and Jinan samples. In contrast, the EPFRs in the Erenhot samples were more affected by dust/sand. The EPFR concentration levels showed a significant positive correlation with the oxidation potentials for the Erenhot and Zhangbei samples and showed negative correlations for the Jinan samples, suggesting that the EPFRs in the Erenhot and Zhangbei samples may provide an important contribution to the oxidative stress in PM_2.5. In contrast, the oxidation potential for the Jinan samples was mainly caused by substances other than EPFRs. This study presents a basic understanding of the potential health effects of Asian dust storms, and this information can be used to assess the health risks of Asian dust storms in future studies.

The Effects of PM2.5 from Asian Dust Storms on Emergency Room Visits for Cardiovascular and Respiratory Diseases

A case-crossover study examined how PM_2.5 from Asian Dust Storms (ADS) affects the number of emergency room (ER) admissions for cardiovascular diseases (CVDs) and respiratory diseases (RDs). Our data indicated that PM_2.5 concentration from ADS was highly correlated with ER visits for CVDs and RDs. The odds ratios (OR) increased by 2.92 (95% CI: 1.22–5.08) and 1.86 (95% CI: 1.30–2.91) per 10 µg/m³ increase in PM_2.5 levels, for CVDs and RDs, respectively. A 10 µg/m³ increase in PM_2.5 from ADSs was significantly associated with an increase in ER visits for CVDs among those 65 years of age and older (an increase of 2.77 in OR) and for females (an increase of 3.09 in OR). In contrast, PM_2.5 levels had a significant impact on RD ER visits among those under 65 years of age (OR = 1.77). The risk of ER visits for CVDs increased on the day when the ADS occurred in Taiwan and the day after (lag 0 and lag 1); the corresponding risk increase for RDs only increased on the fifth day after the ADS (lag 5). In Taiwan’s late winter and spring, the severity of ER visits for CVDs and RDs increases. Environmental protection agencies should employ an early warning system for ADS to reduce high-risk groups’ exposure to PM_2.5.

Do rainfalls wash out anthropogenic airborne magnetic particulates?

We separated dust particles from the mesh-filtered sets of rainwaters collected on rainy days with daily precipitations exceeding 10 mm per day. A total of 136 rainwaters (or snow during the winter season) samples collected from February 2009 to February 2013 were analyzed. In particular, 33 out of 136 rainwaters were collected during or just after the Asian dust storm (ADS) events. Values of pH were relatively higher during warmer seasons. During ADS events, precipitations were alkaline, possibly due to abundant supply of alkaline minerals from the deserts source area to the precipitation. Compositional analysis on particulate matter (PM) indicated that Fe (and Al, K, and Mg) enriched the dusts collected during ADS, with respect to events than those without ADS. We found that ADS rainfall events are effective in selectively eliminating dust particles. However, high rainfall does not necessarily indicate more dilution of dusts. On microscopic examination, we observed natural soils, natural dust of pedogenesis or weathering origin, anthropogenic C-Fe-rich particles, and anthropogenic C-rich particles. Because of its small size, the stoichiometry of ADS-related, Fe-rich dust particles was inferred from the magnetic analysis. Presence of Verwey transition near 100-120 K and experimental determination of Curie points near 580 °C indicate that magnetic mineral responsible for the magnetic properties of ADS-related dusts was magnetite.

Influence of Asian dust storms on daily acute myocardial infarction hospital admissions

OBJECTIVE

This study was the first to explore the relationship between Asian dust storm events (ADS) and acute myocardial infarction (AMI) hospital admissions by applying time series models.

DESIGN AND SAMPLE

Nationwide population-based hospitalization claims data in Taiwan were used. There were 143,063 AMI admissions during 2000-2009.

MEASURES

An autoregressive with exogenous variables (ARX) time series model was used to investigate the dynamic connection between AMI hospital admissions and ADS events.

RESULTS

AMI hospitalizations significantly spiked on post-ADS day three. Among the total population, 3.2 more cases of AMI admissions occurred on post-ADS day three. When the data were stratified by age and gender, the same delayed effect was present in the male population, especially those aged 45-64 and over 74.

CONCLUSIONS

Our study shows that although an ADS event does not cause an immediate incidence of AMI, storms may increase AMI incidence through a delayed effect. Hence, AMI prevention is not only important during a dust storm, but particularly so in subsequent days. During the days after an ADS, exposure to dust should be minimized by staying indoors as much as possible and by wearing a mask when exposure to dust is unavoidable. This is especially true for working and older adults. Nurses at local public health centers can increase awareness and promote public safety by providing health information to local communities regarding the link between dust storms and AMI.

Effects on asthma and induction of interleukin-8 caused by Asian dust particles collected in western Japan

OBJECTIVE

Asian dust storms (ADS) contain various airborne particles that may augment airway inflammation by increasing the level of interleukin-8. The objective of the study was to investigate the association of exposure to an ADS with worsening of symptoms of adult asthma and the effect of ADS particles on interleukin-8 transcriptional activity.

METHODS

The subjects were 112 patients with mild to moderate asthma who recorded scores for their daily upper and lower respiratory tract symptoms and measured morning peak expiratory flow (PEF) from March to May 2011. Interleukin-8 transcriptional activity was assessed in THP-G8 cells that were exposed to airborne particles collected during days of ADS exposure.

RESULTS

Of the 112 patients, 31 had comorbid allergic rhinitis (AR) and/or chronic sinusitis (CS), and had worsened scores for upper respiratory tract symptoms on ADS days compared to non-ADS days. Scores for lower respiratory tract symptoms during ADS days were higher than non-ADS days in all patients. Three patients also had unscheduled hospital visits for exacerbation of asthma on ADS days. However, there was no significant difference in daily morning PEF between ADS and non-ADS days. Airborne particles collected on ADS days induced interleukin-8 transcriptional activity in THP-G8 cells compared to the original soil of the ADS.

CONCLUSION

Exposure to an ADS aggravates upper and lower tract respiratory symptoms in patients with adult asthma. ADS airborne particles may increase airway inflammation through enhancement of interleukin-8 transcriptional activity.