Identification of Endocrine Disrupting Chemicals using a Virus‐Based Colorimetric Sensor

A simple and portable colorimetric sensor based on M13 bacteriophage (phage) was devised to identify a class of endocrine disrupting chemicals, including benzene, phthalate, and chlorobenzene derivatives. Arrays of structurally and genetically modified M13 bacteriophage were fabricated so as to produce a biomimetic colorimetric sensor, and color changes in the phage arrays in response to several benzene derivatives were characterized. The sensor was also used to classify phthalate and chlorobenzene derivatives as representatives of endocrine disrupting chemicals. The characteristic color patterns obtained on exposure to various benzene derivatives enabled similar chemical structures in the vapor phase to be classified. Our sensing approach based on the use of a genetically surface modified M13 bacteriophage offers a promising platform for portable, simple environmental monitors that could be extended for use in numerous application areas, including food monitoring, security monitoring, explosive risk assessment, and point of care testing.     

Solid‐phase microextraction for the human biomonitoring of environmental chemicals: Current applications and future perspectives

Sample preparation is one of the crucial steps in the analytical chemistry including human biomonitoring studies. Although there are several traditional approaches available, solid‐phase microextraction is emerged as one of the pioneering techniques due to its simplicity, rapidness, wide applicability, and miniaturization of traditional sample preparation (e.g., use of less or no organic solvents). There are few earlier review articles available on the advancements in solid‐phase microextraction and its use for the measurement of environmental chemicals in various types of environmental samples. However, a collective information on applicability and current usage of solid‐phase microextraction for the human biomonitoring of environmental chemicals are scarce, nonetheless, rising demands on innovative analytical approaches for human biomonitoring studies. Hence, in this review article, we covered the application of solid‐phase microextraction as extraction/purification methods for more than 15 classes of environmental chemicals to assess their respective exposure levels and associated health outcomes in various human population reported across the globe. Further, a detailed discussion on various types of matrix used, nature of coupled analytical instrumentations, and limitations and future perspectives of solid‐phase microextraction for human biomonitoring studies is presented in this review.     

Microbial growth yield estimates from thermodynamics and its importance for degradation of pesticides and formation of biogenic non-extractable residues

In biodegradation studies with isotope-labelled pesticides, fractions of non-extractable residues (NER) remain, but their nature and composition is rarely known, leading to uncertainty about their risk. Microbial growth leads to incorporation of carbon into the microbial mass, resulting in biogenic NER. Formation of microbial mass can be estimated from the microbial growth yield, but experimental data is rare. Instead, we suggest using prediction methods for the theoretical yield based on thermodynamics. Recently, we presented the Microbial Turnover to Biomass (MTB) method that needs a minimum of input data. We have estimated the growth yield of 40 organic chemicals (31 pesticides) using the MTB and two existing methods. The results were compared to experimental values, and the sensitivity of the methods was assessed. The MTB method performed best for pesticides. Having the theoretical yield and using the released CO₂ as a measure for microbial activity, we predicted a range for the formation of biogenic NER. For the majority of the pesticides, a considerable fraction of the NER was estimated to be biogenic. This novel approach provides a theoretical foundation applicable to the evaluation and prediction of biogenic NER formation during pesticide degradation experiments, and may also be employed for the interpretation of NER data from regulatory studies.     

Monitoring of phthalates in foodstuffs using gas purge microsyringe extraction coupled with GC–MS

Phthalate esters (PAEs) are commonly used as nonreactive plasticisers in vinyl plastics to increase the flexibility of plastic polymers. Numerous studies have indicated that the PAEs as a class of endocrine-disrupting chemicals. In addition, the studies have also shown that a major source of human exposure to phthalates is the diet. To date, the largest problem in PAEs analysis is the high blank value because PAEs are widely used in various applications and products. To overcome this shortcoming, gas purge microsyringe extraction (GP-MSE) was applied, which established a new and low-blank-value analytical method for PAE analysis to analyse PAEs in foodstuffs. In this study, GP-MSE was used as a clean-up method, and the overall recoveries ranged from 85.7 to 102.6%, and the RSD was less than 10%. More importantly, this method can overcome the problem of the high blank value in PAE analysis. This method was applied for measuring PAEs in 78 foodstuffs. The results showed that a wide variety of PAE concentrations were found in the different groups, and the content of PAEs (varies from 658 to 1610 ng g⁻¹ fresh weight) is greatest in seafood. The concentrations were in the following order: DEHP > DBP > DEP ≈ DMP > BBP ≈ DNOP. Finally, the daily intake of PAEs was estimated for adults based on the levels of PAEs in foodstuffs. The total EDI_diet values of 3.2 and 12.9 μg kg⁻¹ bw d⁻¹ were calculated for DEHP based on the mean and highest concentrations in foodstuffs, respectively.     

Comprehensive theoretical analysis and experimental exploration of ultrafast microchip‐based high‐field asymmetric ion mobility spectrometry (FAIMS) technique

High‐field asymmetric ion mobility spectrometry (FAIMS) has become an efficient technique for separation and characterization of gas‐phase ions at ambient pressure, which utilizes the mobility differences of ions at high and low fields. Micro FAIMS devices made by micro‐electromechanical system technology have small gaps of the channels, high electric field and good installation precision, as thus they have received great attentions. However, the disadvantage of relatively low resolution limits their applications in some areas. In this study, theoretical analysis and experimental exploration were carried out to overcome the disadvantage. Multiple scans, characteristic decline curves of ion transmission and pattern recognitions were proposed to improve the performance of the microchip‐based FAIMS. The results showed that although micro FAIMS instruments as a standalone chemical analyzer suffer from low resolution, by using one or more of the methods proposed, they can identify chemicals precisely and provide quantitative analysis with low detection limit in some applications. Copyright © 2015 John Wiley & Sons, Ltd.     

Improved selectivity for the analysis of maternal serum and cord serum for polyfluoroalkyl chemicals

Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid, two of the most widely studied polyfluoroalkyl chemicals (PFCs), can cross the placenta. Therefore, data on the exposure to PFCs of the very young are needed to evaluate the potential health effects associated with such exposure. Human serum, especially serum collected from pregnant women and cord serum, may contain endogenous components that can interfere in the separation by high performance liquid chromatography (HPLC) of PFOS and another PFC of interest, perfluorohexane sulfonic acid (PFHxS), from other serum biomolecules. The presence of such interferences may prevent the adequate quantification of PFOS and PFHxS in cord serum or serum collected from pregnant women, and potentially hinder the assessment of gestational exposure to these important PFCs using biomonitoring. We have modified our on-line solid phase extraction-HPLC-isotope dilution-tandem mass spectrometry analytical method for measuring PFCs in serum and developed an approach that allows for the elimination of these potential interferences without compromising analytical sensitivity and throughput. The combination of acetonitrile as the HPLC mobile phase organic solvent and a Betasil C8 HPLC column provided the best separation of PFOS and PFHxS from interferent peaks. In addition to eliminating these interferences, the acetonitrile method has a shorter runtime and is more sensitive for most PFCs (limits of detection were 0.1 ng/mL except for PFOS (0.2 ng/mL)) than our previous method that used methanol for the HPLC separation. The present method should improve the precise and selective analysis of maternal and cord serum for PFCs.     

固相萃取-衍生化-气相色谱/质谱测定水中类固醇类环境内分泌干扰物

建立了固相萃取-衍生化-气相色谱/质谱联用同时测定水中4种类固醇类环境内分泌干扰物雌酮(E1)、17β-雌二醇(E2)、17α-乙炔基雌二醇(EE2)、雌三醇(E3)的分析方法.通过对比衍生化试剂 N,O-双三甲基硅基三氟乙酰胺(BSTFA)和N-甲基-N-三甲基硅基三氟乙酰胺(MSTFA)的衍生化条件及效果,解释了文...     

Dispersive liquid-liquid microextraction followed by gas chromatography-mass spectrometry for the determination of nitro musks in surface water and wastewater samples

A new, simple, fast and high sensitive analytical method based on dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of nitro musks in surface water and wastewater samples is presented. Different parameters, such as the nature and volume of both the extraction and disperser solvents and the ionic strength and pH of the aqueous donor phase, were optimized. Under the selected conditions (injection of a mixture of 1 mL of acetone as disperser solvent and 50 μL of chloroform as extraction solvent, no salt addition and no pH adjustment) the figures of merit of the proposed DLLME-GC-MS method were evaluated. High enrichment factors, ranging between 230 and 314 depending on the target analyte, were achieved, which redound to limits of detection in the ng L⁻¹ range (i.e., 4-33 ng L⁻¹). The relative standard deviation (RSD) was below 5% for all the target analytes. Finally, the recoveries obtained for different water samples of diverse origin (sea, river, irrigation channel and water treatment plant) ranged between 87 and 116%, thus showing no matrix effects.     

三苯类废气污染及从业人员健康状况调查

为了开展国内精细化工产品生产使用中三苯(苯、甲苯、二甲苯)类废气排放和从业人员健康状况调查研究,为精细化工三苯类废气的治理提供政策依据和管理支持,促进精细化工行业的可持续发展,通过查阅大量相关文献资料,对国内相关企业三苯类废气的污染情况及从业人员健康状况进行调研。结果表明,所调研的皮具、地板、涂料、化工、陶瓷等行业都存在三苯类废气严重污染现象,对从业人员的健康也造成不同程度的损害,因此应加强对三苯类废气污染的治理工作。