International Journal of Environmental Health Engineering
Volume:10 Issue: 3, Sep 2021

 Microplastics (MPs) have become an emerging environmental contaminant and there are increasing concerns about potentially toxic effects on living organisms. This study is aimed to determine uptake, tissue accumulation, and toxic effects of polyurethane microplastics (PUR-MPs) on zebra fish. 

 The zebra fish were exposed to different concentrations of PURs-MPs of different sizes for 10 days. Mortality and behavioral changes were monitored. Ingestion and tissue accumulation of PUR-MPs were studied by fluorescent tagging of PUR-MPs. Pathological damages of tissues were investigated with hematoxylin-eosin staining. 

 Microsize PUR-MPs can be ingested by zebra fish and fluorescent-tagged PUR-MPs were found in gills and gastrointestinal (GI) tract of fish after 10 days of exposure. A significant negative correlation was found between fluorescence intensity in fish tissues and size of PUR-MPs. Gills, GI tract, and liver were the most affected tissues by PUR-MP toxicity. GI damages included epithelial detachment, thinning of the bowel wall, congestive inflammation, epithelial damage, and lesions of villi in the gastric wall. Necrosis, adhesion, and partial fusion of secondary lamellae were the dominant pathological damages in the gills. Liver also was affected by cellular necrosis, infiltration, and lipid droplets. 

 Exposure of zebra fish to PUR-MPs leads to ingestion of these particles by fish and significant increase in fish mortality and tissue damages. Particle size and MP concentration were the key determinant factors in PUR-MP toxicity. The results of the present study provide novel insights into environmental toxicity of PUR-MPs and toxic effect of PUR-MPs in aquatic organisms.

 This study aimed to investigate the level of citizen participation in solid waste recycling in the Isfahan metropolis. 

 To assess the proportionate rate of citizen participation in 15 districts of the city, 400 questionnaires were filled out by participants through stratified random sampling method. The statistical analysis (Correlation and regression analysis) of the data was performed using the SPSS software. 

 The results showed that despite popular belief, the situation of solid waste recycling in Isfahan is unfavorable. Moreover, the highest level of citizen participation is related to district 10 (29.91%) and the lowest amount is associated with district 5 (12.22%). Applying strategies tailored to the social, economical, and cultural characteristics of each district and based on the current level of participation of citizens in each district can improve the current status. 

 The results showed that the citizens need more education to increase their participation in Comprehensive Waste management. However, the provision of educational programs through mass media along with municipality co-operation leads to elevate the people awareness.

 In this study, the microplastic (MP) concentration in several brands of salts was investigated. 

 Fifteen samples of crystallized salt, refined sea salt, unrefined sea salt, and rock salt were purchased from local markets and analyzed for MPs concentration. The salts were digested with the Catalytic Wet Peroxide Oxidation method first, and the MPs were floated based on density difference. Then, MPs were counted by scanning electron microscopy and nature was confirmed by using micro-Raman spectroscopy. 

 The MP concentrations in crystallized salt, refined sea salt, unrefined sea salt, and rock salt were 151.4 ± 48.8, 406.7 ± 93.3, 1417.4 ± 203.3, and 283.4 ± 97.0 MPs/kg, respectively. The most abundant polymers were polyethylene, polypropylene, and polyethylene terephthalate. The fiber was the dominant shape of MPs in all salt samples. 

 This study reveals the presence of MPs in crystallized salt, refined sea salt, unrefined sea salt, and rock salt. Therefore, the consumption of salts can expose humans to MPs.

 The early detection of cardiovascular diseases by noninvasive and low-cost methods such as data mining techniques has been considered by many researchers. This study intends to review the studies performed on the prognosis of coronary heart disease using data mining techniques. 

 The published studies in English between 2001 and 2021 that the use classification methods to predict coronary heart disease were considered. Databases such as ScienceDirect, Web of Science, and ScoPURs were considered as searchable databases. After searching, 348 articles were retrieved. After removing duplicates and evaluating the articles, finally, 20 articles were used. 

 The three data mining techniques support vector machine (SVM), neural network, and naive Bayes which were the most used among the studies. In the most studies, risk factors age, blood pressure, gender, diabetes, and chest pain were used. The accuracy was the most-used measure. The Alizadeh Sani dataset was the most used among the studies. 

 Techniques such as SVM and neural network have performed better than other techniques. The output of these techniques can be used as a decision support system so that clinicians can enter various risk factors such as age, blood pressure, gender, diabetes, and chest pain and then view system output.