Associations between ultrafine particles（UFPs） exposure and occurrence and mortality of cardio-cerebrovascular diseases in Minhang District， Shanghai： a time-series analysis / 上海预防医学

ObjectiveThe study aimed to quantitatively evaluate the short-term effects of ultrafine particles （UFPs） exposure on the occurrence and mortality of cardio-cerebrovascular diseases. MethodsThe number of daily cases of cardio-cerebrovascular events， including stroke and acute myocardial infarction， and mortality of cardio-cerebrovascular diseases， daily concentrations of air pollutants and weather conditions in Minhang， Shanghai from January 1， 2016 to December 31， 2018 were collected. Associations between UFPs and the number of daily cases and deaths were analyzed by the general additive Poisson regression model with the control of meteorological variables， day-of-the-week effects and time trends. Increased percentages of the number of daily cases and deaths and 95%CI were used to indicate the short-term effects of UFPs. ResultsDuring the study period， in the single-pollutant model， an increase of 2022 particles/cm3 showed significant effects with 5.01%（95%CI： 1.22%‒8.94%）and 6.05%（95%CI： 1.53%‒10.80%）increments in the percentages of the number of daily cases and deaths respectively. After adjusting other pollutants in the two-pollutant model， statistically significant associations were also observed. ConclusionUFPs exposure has acute impacts on the occurrence and mortality of cardio-cerebrovascular diseases.

Air pollution and children's health-a review of adverse effects associated with prenatal exposure from fine to ultrafine particulate matter

BACKGROUND@#Particulate matter (PM), a major component of ambient air pollution, accounts for a substantial burden of diseases and fatality worldwide. Maternal exposure to PM during pregnancy is particularly harmful to children's health since this is a phase of rapid human growth and development.@*METHOD@#In this review, we synthesize the scientific evidence on adverse health outcomes in children following prenatal exposure to the smallest toxic components, fine (PM@*RESULTS@#Maternal exposure to fine and ultrafine PM directly and indirectly yields numerous adverse birth outcomes and impacts on children's respiratory systems, immune status, brain development, and cardiometabolic health. The biological mechanisms underlying adverse effects include direct placental translocation of ultrafine particles, placental and systemic maternal oxidative stress and inflammation elicited by both fine and ultrafine PM, epigenetic changes, and potential endocrine effects that influence long-term health.@*CONCLUSION@#Policies to reduce maternal exposure and health consequences in children should be a high priority. PM

Advances in research of effects of ambient ultrafine particles on human health / 上海预防医学

Particulate matters are primary pollutants and ubiquitous in most urban areas of China and prove to be an acknowledged risk to human health, whose degree of harm is realated to the particle size.Ultrafine particles (UFPs) with its diameter less than 0.1 μm may have greater adverse health effects compared with larger ones as fine particulate matters(PM10)and (PM2.5).However, there have been fewer studies and insuffient evidence in this regard.In this review, we analyze recent population-based studies on UFPs exposure and its health impacts and elucidate associations of UFPs exposure with subclinical endpoints changes so as to promote the awreness of UFPs and provide reference for its further research.

Insights Into Emissions and Exposures From Use of Industrial-Scale Additive Manufacturing Machines

BACKGROUND: Emerging reports suggest the potential for adverse health effects from exposure to emissions from some additive manufacturing (AM) processes. There is a paucity of real-world data on emissions from AM machines in industrial workplaces and personal exposures among AM operators. METHODS: Airborne particle and organic chemical emissions and personal exposures were characterized using real-time and time-integrated sampling techniques in four manufacturing facilities using industrial-scale material extrusion and material jetting AM processes. RESULTS: Using a condensation nuclei counter, number-based particle emission rates (ERs) (number/min) from material extrusion AM machines ranged from 4.1×1010 (Ultem filament) to 2.2×1011 [acrylonitrile butadiene styrene and polycarbonate filaments). For these same machines, total volatile organic compound ERs (mg/min) ranged from 1.9×104 (acrylonitrile butadiene styrene and polycarbonate) to 9.4×104 (Ultem). For the material jetting machines, the number-based particle ER was higher when the lid was open (2.3×1010 number/min) than when the lid was closed (1.5–5.5×109 number/min); total volatile organic compound ERs were similar regardless of the lid position. Low levels of acetone, benzene, toluene, and m,p-xylene were common to both AM processes. Carbonyl compounds were detected; however, none were specifically attributed to the AM processes. Personal exposures to metals (aluminum and iron) and eight volatile organic compounds were all below National Institute for Occupational Safety and Health (NIOSH)-recommended exposure levels. CONCLUSION: Industrial-scale AM machines using thermoplastics and resins released particles and organic vapors into workplace air. More research is needed to understand factors influencing real-world industrial-scale AM process emissions and exposures.

Characterization of coal fly ash nanoparticles and their induced in vitro cellular toxicity and oxidative DNA damage in different cell lines.

Coal combustion generates considerable amount of ultrafine particles and exposure to such particulate matter is a major health concern in the developing countries. In this study, we collected nano sized coal fly ash (CFA) and characterized them by scanning electron microscope-energy dispersive X-ray analysis (SEM-EDX), particle size analyzer (PSA) and transmission electron microscope (TEM), and investigated its toxicity in vitro using different cell lines. The imaging techniques showed that the coal fly ash nanoparticles (CFA-NPs) are predominately spherical shaped. The analyses have revealed that the CFA-NPs are 7-50 nm in diameter and contain several heavy metals associated with CFA particles. The studies showed significant amount of toxicity in all cell lines on treatment with CFA-NPs. The cytotoxicity and oxidative DNA damage caused by CFA-NPs were determined by inhibition of cellular metabolism (MTT), total intracellular glutathione (GSH), reactive oxygen species (ROS) and DNA fragmentation in cultured cell lines (Chang liver, HS294T and LL29). The cellular metabolism was inhibited in a dose-dependent manner in CFA-NPs treated cell lines. The CFA-NPs induced ROS and decreased the total intracellular glutathione with increased dose. Further, the CFA-NPs treated cells showed severe DNA laddering as a result of DNA fragmentation.

Comparative Study of Clinical Efficacy of Ultrafine Extracted Granule Preparation and Traditional Herbal Decoction of Li Zhong Tang / 中国中医药信息杂志

Objective To compare the clinical efficacy of different doses of ultrafine extracted granule preparation (EGP) and traditional herbal decoction (THD) of Li Zhong Tang in treatment of epigastric pain. Methods Sixty cases of epigastric pain patients in accordance with the diagnostic criteria of deficiency and cold pattern of spleen and stomach in TCM were randomly divided into THD group, 1/3 dose group and 1/5 dose group, and were given THD, 1/3 dose of ultrafine EGP and 1/5 dose of ultrafine EGP, respectively. The clinical efficacy of the three groups after one course of medication was comparatively analyzed. Results There were no significant differences in age, course of disease, symptom score before treatment, epigastric pain efficacy and syndrome curative effect among the three groups, the differences had no statistical significance (P>0.05). The severity, frequency and duration of epigastric pain were all reduced in the three groups, with significant differences between before and after treatment (P<0.05). Conclusion There are no significant differences in the clinical efficacy on epigastric pain among THD, 1/3 dose of ultrafine EGP and 1/5 dose of ultrafine EGP. In addition, the effect of 1/3 dose group is very close to the THD group.

Estudio exploratorio de higiene industrial en ambientes de trabajo donde se producen o utilizan nanopartículas / Exploratory study of industrial hygiene in work areas where nanoparticles are produced or used

Se realizó un estudio exploratorio con los objetivos de identificar empresas que produzcan o manipulen nanopartículas en Chile, evaluar los riesgos para la salud de estas actividades y entregar recomendaciones para su control. Se encontró que la nanotecnología está en una etapa incipiente, con un reducido número de aplicaciones en procesos industriales, concentrándose el desarrollo y aplicación principalmente en centros de investigación de las universidades, donde los investigadores y estudiantes son el principal grupo de potenciales expuestos. Para evaluar la exposición en las empresas e instituciones identificadas, se utilizó un método cualitativo simplificado y un método cuantitativo que se basa en las técnicas tradicionales de higiene ocupacional complementadas con la caracterización de las nanopartículas mediante microscopía electrónica. Se evalúa la exposición a nanopartículas de cobre, carbonato de calcio y partículas ultrafinas de humos de soldadura. La metodología de evaluación cualitativa, si bien requiere algún grado de acondicionamiento, demostró ser una herramienta particularmente útil para definir sistemas de protección en el caso de las nanopartículas, cuya toxicidad es incierta y de las cuales no se tienen establecidas técnicas de medición ni límites permisibles. Los métodos de medición tradicionales de la higiene industrial no entregan la información suficiente para evaluar la exposición, debiendo ser complementados con microscopía electrónica para caracterizar el tamaño y composición química, parámetros claves en la toxicidad de las nanopartículas. El trabajo realizado entrega una base de información y conocimiento a nivel exploratorio, que se estima útil para evaluar el riesgo de exposición en aplicaciones que pudieran surgir en el contexto actual del desarrollo de la nanotecnología en nuestro país.

An exploratory research was developed in order to identify companies which produce or handle nanoparticles in Chile, evaluate the risks for health from these activities and give suggestions for controlling them. It was found that nanotechnology is in an incipient stage, with a reduced numbers of applications in industrial processes, focusing the development and application mainly on research centers in Universities, where researchers and students are the main exposed potential groups. To evaluate the exposure in identified companies and institutions, it was used a qualitative simplified method and a quantitative method which is based in traditional technique of occupational hygiene complemented by the characterization of nanoparticles with electronic microscopy. It was evaluated the exposure to nanoparticles of copper, calcium carbonate and welding smoke ultrafine particles. The methodology of qualitative evaluation, although requires some degree of conditioning, showed being a especially useful tool to define protection systems in nanoparticles case, whose toxicity is uncertain and we do not have established techniques of measuring them or permissible limits. Traditional measuring methods of industrial hygiene do not bring enough information to evaluate the exposure, and they must be complemented with electronic microscopy to characterize the size and chemical composition, key parameters in nanoparticles toxicity. This work provides a base of information and knowledge in a exploratory level, which is estimated as a useful tool to evaluate the exposure risk in applications that may appear in the current nanotechnology development in our country.

Exposure and Toxicity Assessment of Ultrafine Particles from Nearby Traffic in Urban Air in Seoul, Korea

OBJECTIVES: We investigated the particle mass size distribution and chemical properties of air pollution particulate matter (PM) in the urban area and its capacity to induce cytotoxicity in human bronchial epithelial (BEAS-2B) cells. METHODS: To characterize the mass size distributions and chemical concentrations associated with urban PM, PM samples were collected by a 10-stage Micro-Orifice Uniform Deposit Impactor close to nearby traffic in an urban area from December 2007 to December 2009. PM samples for in vitro cytotoxicity testing were collected by a mini-volume air sampler with PM10 and PM2.5 inlets. RESULTS: The PM size distributions were bi-modal, peaking at 0.18 to 0.32 and 1.8 to 3.2 microm. The mass concentrations of the metals in fine particles (0.1 to 1.8 microm) accounted for 45.6 to 80.4% of the mass concentrations of metals in PM10. The mass proportions of fine particles of the pollutants related to traffic emission, lead (80.4%), cadmium (69.0%), and chromium (63.8%) were higher than those of other metals. Iron was the dominant transition metal in the particles, accounting for 64.3% of the PM10 mass in all the samples. We observed PM concentration-dependent cytotoxic effects on BEAS-2B cells. CONCLUSIONS: We found that exposure to PM2.5 and PM10 from a nearby traffic area induced significant increases in protein expression of inflammatory cytokines (IL-6 and IL-8). The cell death rate and release of cytokines in response to the PM2.5 treatment were higher than those with PM10. The combined results support the hypothesis that ultrafine particles from vehicular sources can induce inflammatory responses related to environmental respiratory injury.

Biocompatible Dispersion Methods for Carbon Black

The biological activity of particles is largely dependent on their size in biological systems. Dispersion in the aqueous phase has been both a critical impediment to and a prerequisite for particle studies. Carbon black has been used as a surrogate to investigate the biological effects of carbonaceous particles. Here, biocompatible methods were established to disperse carbon black into ultrafine and fine particles which are generally distinguished by the small size of 100 nm. Carbon black with a distinct particle size, N330 and N990 were suspended in blood plasma, cell culture media, Krebs-Ringer's solution (KR), or physiological salt solution (PSS). Large clumps were observed in all dispersion preparations; however, sonication improved dispersion - averaged particle sizes for N330 and N990 were 85.0 +/- 42.9 and 112.4 +/- 67.9 nm, respectively, in plasma; the corresponding sizes in culture media were 84.8 +/- 38.4 and 164.1 +/- 77.8 nm. However, sonication was not enough to disperse N330 less than 100 nm in either KR or PSS. Application of Tween 80 along with sonication reduced the size of N330 to less than 100 nm, and dispersed N990 larger than 100 nm (73.6 +/- 28.8 and 80.1 +/- 30.0 nm for N330 and 349.5 +/- 161.8 and 399.8 +/- 181.1 nm for N990 in KR and PSS, respectively). In contrast, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) exhibited little effect. Electron microscopy confirmed the typical aciniform structure of the carbon arrays; however, zeta potential measurement failed to explain the dispersibility of carbon black. The methods established in this study could disperse carbon black into ultrafine and fine particles, and may serve as a useful model for the study of particle toxicity, particularly size-related effects.

Respiratory Health among Korean Pupils in Relation to Home, School and Outdoor Environment

There are few studies about school-environment in relation to pupils' respiratory health, and Korean school-environment has not been characterized. All pupils in 4th grade in 12 selected schools in three urban cities in Korea received a questionnaire (n = 2,453), 96% participated. Gaseous pollutants and ultrafine particles (UFPs) were measured indoors (n = 34) and outdoors (n = 12) during winter, 2004. Indoor dampness at home was investigated by the questionnaire. To evaluate associations between respiratory health and environment, multiple logistic- and multi-level regression models were applied adjusting for potential confounders. The mean age of pupils was 10 yr and 49% were boys. No school had mechanical ventilation and CO2-levels exceeded 1,000 ppm in all except one of the classrooms. The indoor mean concentrations of SO2, NO2, O3 and formaldehyde were 0.6 microg/m3, 19 microg/m3, 8 microg/m3 and 28 microg/m3, respectively. The average level of UFPs was 18,230 pt/cm3 in the classrooms and 16,480 pt/cm3 outdoors. There were positive associations between wheeze and outdoor NO2, and between current asthma and outdoor UFPs. With dampness at home, pupils had more wheeze. In conclusion, outdoor UFPs and even low levels of NO2 may adversely contribute to respiratory health in children. High CO2-levels in classrooms and indoor dampness/mold at home should be reduced.