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21.
AimsThe rising prevalence of metabolic syndrome has made it a major health concern. Chronic occupational exposure to organic solvents affects different systems of the body. This study aimed to investigate the association between exposure to organic solvents and the prevalence of metabolic syndrome in petroleum refinery workers.MethodThis study was conducted in 2019–2020 on workers employed in an Iranian petroleum refinery. The demographic and occupational information on the participants was obtained using the interview method. Their height, weight, and blood pressure were measured by the occupational health team, and fasting blood samples were taken from them to measure the paraclinical parameters.ResultsIn this study, 1009 petroleum refinery workers were analyzed. The prevalence of metabolic syndrome in workers was 20.1% and it was about two times higher in exposed workers (CI 95%: 1.61–3.35) compared to non-exposed ones. Factors associated with the prevalence of metabolic syndrome include age, higher BMI, exercise, and longer exposure to organic solvents.ConclusionFindings of this study suggested that exposure to organic solvents is associated with increased prevalence of metabolic syndrome (the highest association was observed with elevated serum triglycerides). Besides, longer exposure to organic solvents increased the risk of developing metabolic syndrome.  相似文献   
22.
A retrospective exposure assessment was performed for use in a health outcomes study of a facility manufacturing circuit boards, business machines, and other equipment during the years 1969–2002. A matrix was developed identifying chemical use by department-year based on company-provided information. Use of six chemical agents (fiberglass, lead, methylene chloride, methyl chloroform, perchloroethylene, and trichloroethylene) and six chemical classes (acid-base, aromatic hydrocarbons, chlorinated hydrocarbons, other hydrocarbons, chlorofluorocarbons, and metals), and general (including unspecified) chemicals was identified. The matrix also contained an assignment for each department-year categorizing the potential for use of chemicals as negligible, intermittent/incidental, or routine. These department-based exposure matrix data were combined with work history data to provide duration of potential chemical use for workers. Negligible, intermittent/incidental or routine extent-of-chemical-use categories comprised 42.6%, 39.4%, and 17.9%, respectively, of total person-years of employment. Cumulative exposure scores were also developed, representing a relative measure of the cumulative extent of potential exposure to the six chemical agents, six chemical classes, and general (including unspecified) chemicals. Additionally, the study period was divided into manufacturing eras showing trends in chemical use, and showing that process use of trichloroethylene and methylene chloride ended in the mid-1980s and the mid-1990s, respectively. This approach may be useful in other assessments addressing a variety of chemicals, and with data constraints common to retrospective chemical exposure studies.  相似文献   
23.
Deep eutectic solvents (DESs) were used as environmentally benign and straightforward replacements for the harmful organic solvents and transition metal-based catalysts in various organic syntheses. Here, we report a DES as a mild, biocompatible, and environmentally friendly dual solvent/catalyst for the one-pot construction of 2-amino-5-alkylidenethiazol-4-ones throw one-pot reaction of carbonyl compounds, nitrogen compounds, and rhodanine up to quantitative yields within a latent period of times. This green procedure has a more diverse and broader scope regarding starting materials and exhibits excellent conversion and high selectivity. In particular, DES displays better durability and reusability in the multicomponent reactions than traditional catalysts and solvents without distinct deterioration in catalytic activity.  相似文献   
24.
阮昊  陈悦 《中国药师》2015,(11):2000-2002
摘 要 目的: 建立顶空进样气相色谱法检测比卡鲁胺原料药中7种有机残留溶剂二氯甲烷、正己烷、四氢呋喃、乙醇、乙醚、丙酮和乙酸乙酯的方法。方法: 色谱柱为Agilent DB 624弹性石英毛细管柱(30.0 m×0.25 mm×1.4 μm);进样口温度:200℃;氢火焰离子化检测器(FID)温度:250℃;柱温:程序升温,初始温度35℃,保持13 min,再以100℃/min的速率升至180℃,维持5 min;载气:氮气;流速:1.2 ml·min-1。顶空进样,顶空平衡温度:90℃,顶空平衡时间:30 min;进样体积:1.0 ml;以二甲基亚砜为溶解介质,测定比卡鲁胺中7种溶剂的残留量。结果: 各被测溶剂均能良好分离,各溶剂峰面积与浓度均呈良好的线性关系,回收率均较为理想。 结论:该法适用于比卡鲁胺原料药中残留溶剂的测定。  相似文献   
25.
Glycerol is the main co-product from biodiesel production and has been recognized as a sustainable solvent. Herein, we used glycerol and waste glycerol in synthesis of two bioactive α,β-unsaturated ketones (E,E)-1,5-diphenylpenta-2,4-dien-1-one (1) and (E,E)-2,6-dibenzylidenecyclohexanone (2), using aldol mono- and di-condensation reactions, respectively. Crude yield values were calculated from product mass after precipitation and drying. Purity was measured by High Performance Liquid Chromatography with Photodiode Array (HPLC-PAD) using analytical curves and reference compounds. Glycerol and waste glycerol were able to furnish 1 and 2 in higher crude yields and HPLC-PAD purities values than other protic solvents (ethanol, methanol, PEG-400 and water). In order to investigate reasons of glycerol efficiency when compared to water efficiency, we performed computational calculations using Density Functional Theory (DFT). Theoretical predictions confirmed the E1cB mechanism, as well as favourable energy barrier using glycerol in comparison to water, corroborating their sustainable properties. In addition, waste glycerol from corn and sunflower oil transesterifications were used in the synthesis of 1 and 2 for four recycles, displaying good crude yields and HPLC-purities.  相似文献   
26.
目的 探讨职业性有机溶剂中毒的临床表现、神经影像学特征、治疗及预后。方法 回顾性分析15例职业性有机溶剂中毒患者的临床资料。结果 15例患者均急性或亚急性起病,有明确的有机溶剂职业接触史,主要临床表现包括头晕(73.3%)、认知功能下降(60%)、锥体束损害(53.3%)、颅内高压综合征(46.7%)、意识障碍(33.3%); 其中14例患者头颅磁共振成像(Magnetic resonance imaging,MRI)显示为弥漫性脑组织肿胀,以双侧大脑半球白质为主,呈“火焰状”,10例累及双侧基底节(苍白球),8例累及双侧小脑齿状核,呈“肾形”改变,5例累及双侧丘脑; 所有患者使用脱水剂、糖皮质激素及高压氧等综合治疗后,其中12例患者好转出院,无或仅遗留轻微后遗症,3例患者无明显改善,预后差。结论 职业性有机溶剂中毒以头晕、认知功能下降、锥体束损害、颅内高压综合征及意识障碍等中毒性脑病表现为主,典型头颅MRI为双侧大脑半球白质、苍白球及小脑齿状核对称性病变,结合患者职业接触史需考虑本病; 早期、长程、足量给予脱水剂、糖皮质激素及高压氧等综合治疗,大多数患者预后良好。  相似文献   
27.
Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs.  相似文献   
28.
王海波  陈宁周  朱斌 《中国药师》2014,(11):1888-1890
目的:采用气相顶空色谱法测定马来酸氟吡汀原料药中的甲醇、乙醇和异丙醇3种有机溶剂的残留量。方法:采用DB-624(30 m×0.53 mm,3.0μm)毛细管色谱柱,载气为氮气,程序升温。FID检测器,温度为250℃。进样口温度为200℃。按外标法测定溶剂残留量。结果:甲醇,乙醇和异丙醇分别在2.182-152.74(r=0.999 1),3.546-248.22(r=0.999 8)和4.082-285.74μg·m^l-1(r=0.999 7)范围内,线性关系良好;平均回收率分别为97.7%(RSD=1.5%),99.0%(RSD=1.1%),98.8%(RSD=1.1%)(n=5)。结论:本方法简便、准确,灵敏度高,适用于马来酸氟吡汀原料药中有机溶剂残留量的检测。  相似文献   
29.
目的:建立苯妥英钠中甲醇等5种残留溶剂的测定方法.方法:采用顶空毛细管气相色谱法测定,水为溶剂,色谱柱为HP-624(30.0 m × 530 μm,3.00 μm);载气为氮气;检测器为FID;程序升温,初始温度为40℃,维持5 min,以20℃·min-升温至200℃,保持5 min.结果:测得各残留溶剂的线性关系良好(相关系数>0.997 2);平均回收率92.1%~100.9%,检测限为0.5~1.2 μg.结论:该法操作简便,重现性好,结果准确可靠,可用于苯妥英钠中5种残留溶剂的测定.  相似文献   
30.
王发  王莉  王嫦鹤  张秉华 《安徽医药》2014,(12):2260-2262
目的:建立尼美舒利原料药中8种有机溶剂残留量的顶空毛细管气相色谱测定法。方法使用Agilent DB-WAX毛细管柱(30 m ×0.32 mm ×0.5μm),氢火焰离子检测器,进样口温度230℃,检测器温度250℃。程序升温,初温50℃,保持5 min,然后以15℃· min-1的速率升至120℃,再以30℃·min-1的速率升至240℃,保持5 min。顶空进样,平衡温度95℃,平衡时间30 min。结果在上述条件下,正己烷,丙酮,甲醇,二氯甲烷,乙醇,甲苯,吡啶,正丁醇分离度均在2.0以上,线性关系良好(r分别为0.9997,0.9992,0.9976,0.9987,0.9988,0.9993,0.9988,0.9988),平均回收率(n=6)均在97%以上。结论该法简单、准确,灵敏度高,重复性好,适用于尼美舒利原料药中有机溶剂残留量的测定。  相似文献   
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