磁固相萃取-HPLC测定环境空气中的苯并[a]芘

本文建立了磁性固相萃取结合高效液相色谱法测定环境空气中苯并[a]芘的新方法。空气滤膜中的苯并[a]芘经乙腈超声提取,20mg Fe_3O_4-SiO_2-G涡旋萃取,用1mL乙腈洗脱后经HPLC测定。结果表明,苯并[a]芘在0.02～2.0μg·mL~(-1)的浓度范围内具有良好的线性关系,相关系数R~2=0.9991,检出限为0.06ng·m~(-3),定量限为0.2ng·m~(-3),回收率为91.0%～102.2%,相对标准偏差为3.1%～8.2%,实际样品的分析结果与HJ956-2018的偏差≤10%。该法快速简便、灵敏度高、成本较低,具有良好的重现性和准确性,适用于大批量样品的检测分析,可做为环境空气中苯并[a]芘的日常监测方法,并为其它污染物的检测提供参考。     

食用植物油中苯并(a)芘荧光光度法检测结果分析

用中性氧化铝对86份植物油中苯并(a)芘进行净化,用高效液相色谱-荧光光度法测定苯并(a)芘含量,外标法定量。结果表明,食用植物油中苯并(a)芘的检出率为4.65%(4份散装花生油样本),超标率占样品总数的1.16%(仅有1份花生油样本检出超标)。食用植物油中苯并(a)芘污染最严重的是花生油,大豆油、玉米(胚芽)油和调和油均未检出。     

垃圾焚烧炉飞灰中苯并[a]芘分析方法研究

用丙酮作溶剂超声波抽提垃圾焚烧炉飞灰中苯并[a]芘有机物,再用固相萃取纯化,然后利用配ODS3C18色谱柱的高效液相色谱仪,在以90%乙腈+10%水为流动相,流速为1mL/min,激发波长246nm和发射波长431nm的条件下测定了垃圾焚烧炉飞灰中的苯并[a]芘含量。结果表明:该方法检出限为0.01ng/mL,苯并[a]芘的回收率90.8%,方法的RSD(相对标准偏差)为3.89%。     

微波-吸波介质处理炼焦烟气中五环多环芳烃

五环多环芳烃苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽属于高环多环芳烃,降解难度高、危害大,其中苯并[a]芘危害性最大,具有很强的致毒性和致癌性。通过竖式电炉模拟制备炼焦烟气,采用微波和吸波介质协同处理的方法,以二氯甲烷和玻璃纤维对多环芳烃进行收集,通过超声波萃取、高效液相色谱法检测技术,定性、定量分析炼焦烟气产生的五环多环芳烃,研究了微波-吸波介质处理五环多环芳烃实验时微波温度,以及吸波介质的质量、粒径、种类等实验因素对4种多环芳烃各分量及总量降解效果的影响。实验结果表明,当微波温度400℃、碳化硅吸波介质6 g时,总的降解率为72%,苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽降解率分别为79%、75%、72%和48%,处理效果较好,尤其苯并[a]芘降解率最高。     

超高效液相-荧光检测器法测定柴油中多环芳烃

建立了采用超高效色谱(UPLC)-荧光检测器法测定柴油中10种常见的多环芳烃含量的方法。这10种常见的多环芳烃为萘、苊、二氢苊、芴、菲、蒽、荧蒽、芘、苯并[a]蒽、艹屈、苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘和苯并[g,h,i]芘。样品经过固相萃取后用甲醇溶解,采用Acquity UPLC BEH Phenyl C18柱(100 mm×2.1 mm,1.7μm)分离,乙腈-水为流动相进行梯度洗脱,采用荧光检测器检测,并用外标法进行定量分析。结果表明,在一定质量浓度范围内,峰面积与质量浓度的线性关系良好,用标准加入法进行回收率实验,对方法的准确度进行考察,相对标准偏差为0.56%⁸.76%,加标回收率为100.04%8.76%,加标回收率为100.04%¹15.04%。与其他检测柴油中多环芳烃方法比较,该方法简单,分离效果好,快速及准确。     

高效液相色谱-荧光检测法测定贝类中15种多环芳烃

建立了高效液相色谱-程序荧光检测法同时测定贝类中15种多环芳烃的方法。通过液相色谱柱、荧光激发和发射波长等条件的优化,实现15种多环芳烃组分基线完全分离和荧光高灵敏度检测。在优化的实验条件下,检测的15种多环芳烃中萘、苊和芴的检出限为0.5μg/kg,苯并[b]荧蒽、二苯并[a,h]蒽和苯并[g,h,i]苝的检出限为2.0μg/kg,其余化合物的检出限为1.0μg/kg;在检测的15种多环芳烃中,菲、蒽、芘、苯并[a]蒽、崫、苯并[a]芘、茚并[1,2,3-cd]芘在0.001~0.5 mg/L浓度范围,其余化合物在0.002~1.0 mg/L浓度范围,呈良好的线性相关,相关系数r0.995;当样品加标水平分别为2、10、100μg/kg时,回收率在71.1%~98.4%,RSD10%。该检测方法重现性高,检测灵敏度和准确度均满足分析要求。     

焦化厂污染土壤中多环芳烃降解菌群解析

以苯并[a]芘、苯并[a]蒽、苯并[b]荧蒽、苯并[k]荧蒽、茚并[1,2,3-cd]芘5种较难降解的多环芳烃为碳源和能源,采用富集培养的方法从焦化厂污染的土壤中筛选分离得到50株PAHs降解菌。通过对其16S rRNA基因序列分析,将这些PAHs降解菌分为15个种群,分别属于Sphingomonas(鞘氨醇单胞菌属)、Methylobacterium(甲基杆菌属)、Burkholderia(伯克霍尔德氏菌属)、Rhodococcus(红球菌属)、Bradyrhizobium(慢生根瘤菌属)、Phyllobacterium(叶杆菌属)、Chryseobacterium(金黄杆菌属)、Microbaterium(微杆菌属)8个属,其中优势菌为鞘氨醇单胞菌属。纯菌株降解能力测试表明,培养12 d后,菌株3-6-12降解效果要优于其他菌株,对苯并[a]蒽、苯并[a]芘、苯并[b]荧蒽、苯并[k]荧蒽、茚并[1,2,3-cd]芘的降解率分别可达39.64%、33.52%、38.57%、25.37%、31.17%。实验结果可为多环芳烃污染土壤的生物修复提供高效的降解菌源。     

超高效液相-荧光检测器法测定柴油中多环芳烃

建立了采用超高效色谱(UPLC)-荧光检测器法测定柴油中10种常见的多环芳烃含量的方法。这10种常见的多环芳烃为萘、苊、二氢苊、芴、菲、蒽、荧蒽、芘、苯并[a]蒽、艹屈、苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘和苯并[g,h,i]芘。样品经过固相萃取后用甲醇溶解,采用Acquity UPLC BEH Phenyl C18柱(100 mm×2.1 mm,1.7μm)分离,乙腈-水为流动相进行梯度洗脱,采用荧光检测器检测,并用外标法进行定量分析。结果表明,在一定质量浓度范围内,峰面积与质量浓度的线性关系良好,用标准加入法进行回收率实验,对方法的准确度进行考察,相对标准偏差为0.56%~8.76%,加标回收率为100.04%~115.04%。与其他检测柴油中多环芳烃方法比较,该方法简单,分离效果好,快速及准确。     

不同抽吸模式对卷烟主流烟气中苯并[a]芘的影响研究

为考察不同抽吸模式对卷烟主流烟气中苯并[a]芘释放量的影响,本研究采用ISO、Massachusetts、Health Canada和补偿抽吸4种抽吸方式分别抽吸了5种卷烟样品,采用气相色谱-质谱联用法测定了主流烟气中的苯并[a]芘释放量。研究表明:与ISO方案相比,采用Massachusetts、Health Canada和补偿抽吸的抽吸方式,卷烟主流烟气中苯并[a]芘释放量均有所提高。     

GC-MS法测定电子烟烟气中的苯并[a]芘

采用气相色谱-质谱联用法(GC-MS)测定电子烟烟气中的苯并[a]芘,电子烟样品在ISO标准抽吸模式,采用单层剑桥滤片对电子烟烟气释放物中的粒相部分进行捕集。待抽吸完毕后,将剑桥滤片以环己烷溶液超声萃取并浓缩用以测定。该方法中苯并[a]芘的检出限为4.5 ng/m L,定量限为15 ng/m L,样品中苯并[a]芘加标回收率在95.5%~97.6%之间。结果表明:该方法具有基质干扰少、定量准确、灵敏度高等特点。     

Determination of Mineral Oil-Saturated Hydrocarbons (MOSH) in Vegetable Oils by Large Scale Off-Line SPE Combined with GC-FID

A method based on an off-line large-scale solid phase extraction (SPE) approach combined with conventional gas chromatographic-flame ionization detection (GC-FID) was developed to determine the mineral oil-saturated hydrocarbons (MOSH) in vegetable oils. A large-scale SPE column loaded with 10 g of activated silica gel impregnated with 1% silver nitrate which was used to retain lipids and olefins in vegetable oils and the MOSH in the oil samples was eluted with hexane. Then 2 μL concentrated solution was splitlessly injected into a common GC-FID instrument. The quantification limit reached 2.5 mg/kg when the MOSH fraction was concentrated to 0.1 mL. The accuracy of this procedure, as assessed by measuring the recoveries from spiked oil samples, was higher than 80%. This procedure was applied to analyze the MOSH in 38 commercial vegetable oils from Chinese market, which was the first survey of mineral oil contaminant in Chinese edible oils. The oil samples contaminated with different levels of MOSH, among which, 15 samples contained no mineral oils and 3 samples were contaminated with more than 50 mg/kg of MOSH. The highest contamination level was found in one of rice oils, in which the concentration of MOSH was up to 713.36 mg/kg. Of the 9 types of oils analyzed, camellia oil contained MOSH ranging between 6.76 and 78.49 mg/kg, averaging 46.72 mg/kg, indicating a higher contamination level than other types of oils. The results suggested that it is necessary to routinely detect mineral oil contamination in vegetable oils for food safety.     

Detection of polycyclic aromatic hydrocarbons in commonly consumed edible oils and their likely intake in the Indian population

Edible oils such as coconut, groundnut, hydrogenated vegetable, linseed, mustard, olive, palm, refined vegetable, rice bran, safflower, sesame, soybean, and sunflower were analyzed for the presence of light and heavy polycyclic aromatic hydrocarbon (PAH) residues using liquid-liquid extraction, cleanup on a silica gel column, and resolution and determination by HPLC using a fluorescence detector. Ten PAH viz. acenaphthene, anthracene, benzo(a)pyrene, benzo(e)pyrene, benz(ghi)perylene, chrysene, coronene, cyclopenta(def)phenanthrene, phenanthrene, and pyrene were monitored. Analysis of 296 oil samples showed that 88.5% (262) samples were contaminated with different PAH. Of 262 contaminated edible oil samples, 66.4% of the samples showed PAH content of more than the 25 μg/kg recommended by the German Society for Fat Science. The total PAH content was highest in virgin olive oil (624 μg/kg) and lowest in refined vegetable oils (40.2 μg/kg). The maximum content (265 μg/kg) of heavy PAH was found in olive oil and the minimum (4.6 μg/kg) in rice bran oil. Phenanthrene was present in 58.3% of the oil samples analyzed, followed by anthracene (53%). Among the heavy PAH, benzo(e)pyrene was observed in 31.2% of the samples followed by benzo(a)pyrene (25.5%). The intake of PAH was highest through olive oil (20.8 μg/day) followed by soybean oil (5.0 μg/day) and lowest through refined vegetable oil (1.3 μg/day). Based on these monitoring studies, international and national guidelines for permissible levels of PAH can be prepared so as to restrict the intake of these toxic contaminants.     

Extraction of Polycyclic Aromatic Hydrocarbons in Barn Owls ( Tyto Alba ) from Northwest Spain by SFE and HPLC-FL Analysis

Supercritical fluid extraction (SFE) and high-performance liquid chromatography-fluorescence detection (HPLC-FL) were used to determine concentration of anthracene, benzo[ a ]anthracene, benzo[ a ]pyrene, benzo[ b ]fluoranthene, benzo[ ghi ]perylene, benzo[ k ]fluoranthene, chrysene, fluoranthene, pyrene, and indeno[1,2,3- cd ]pyrene in six classes of tissue (heart, liver, intestine, muscle, lung, and kidney) of 11 barn owls from Galicia (northwest Spain). We have detected fluoranthene and pyrene in >40.0% of samples, anthracene in 35.4%, and benzo[ a ]anthracene in 12.3%. Mean concentrations were between 0.398 w g/kg dry weight for anthracene and 4.855 w g/kg dry weight for fluoranthene. Lung and intestine tissues were more polluted than the other tissues.     

Polycyclic Aromatic Hydrocarbons (PAHs) Occurrence and Toxicity in Camellia sinensis and Herbal Tea

ABSTRACT

This study describes a survey of polycyclic aromatic hydrocarbon (PAH) concentrations in 23 green, herbal, and black tea brands widely consumed in Nigeria by determining the levels of benzo[a]pyrene, chrysene (PAH2), benzo[a]pyrene, chrysene, benz[a]anthracene, benzo[b]fluoranthene (PAH4), benzo[a]pyrene, benz[a]anthracene, benzo[k]fluoranthene, chrysene, benzo[b]fluoranthene, dibenz[ah]anthracene, benzo[ghi]per-ylene and indeno[1,2,3-cd]pyrene (PA-H8). Toxic equivalence factor and mutagenic equivalence factor were applied to evaluate the toxic equivalence and mutagenic equivalence quotients relative to benzo[a]pyrene. The concentrations of PAHs indicate that Regulation 835/2011/EC was not fulfilled by benzo[a]anthracene, B[a]A, benzo[a]pyrene, B[a]P, benzo[b]fluoranthene, B[b]F, and chrysene, CHR. The PAH4 levels ranged from 1.28 to 44.57, 4.34 to 11.20, and 0.76 to 34.82 µg/kg in green, black, and herbal tea products, respectively. On the other hand, the PAH8 concentration varied between 1.63 and 65.73, 5.02 and 68.83, and 12.43 and 24.92 µg/kg in green, herbal, and black tea samples. The PAH4 and PAH8 provide more reliable indicators for determination of PAH contamination and risk characterization in food than PAH2.     

Contamination of Soil by Polycyclic Aromatic Hydrocarbons in Some Urban Areas

The contamination by 16 polycyclic aromatic hydrocarbons (PAHs) in surface soils, sampled at a 0-5 cm depth in the urban areas of Tallinn, Helsinki, Vilnius, Chicago, London is reported. All samples were analyzed using the same protocol. The median concentrations ( w g/kg) were found to be 117, 539, 127, 3,263, 1,728 for pyrene; 62, 236, 43, 1,634, 1,652 for benzo[ a ]pyrene; 86, 304, 92, 2,295, 2,068 for benzo[ a ]pyrene toxic equivalents, calculated using the benzo[ a ]pyrene toxic equivalency factors; 467, 1,471, 392, 8,981, 6,837 for a total of seven probable human carcinogenic PAHs: benzo[ a ]anthracene, chrysene, benzo[ b ]fluoranthene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, dibenz[ ah ]anthracene, indeno[1,2,3- cd ]pyrene; 911, 2,941, 672, 16,183, 13,718 for the total of 16 PAHs, recommended by the U.S. Environmental Protection Agency: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[ a ]anthracene, chrysene, benzo[ b ]fluoranthene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, dibenz[ ah ]anthracene, benzo[ ghi ]perylene, indeno[1,2,3- cd ]pyrene in Tallinn ( n = 3), Helsinki ( n = 3), Vilnius ( n = 15), Chicago ( n = 4), London ( n = 3), respectively. The size of the population is a statistically significant factor in urban soil contamination by high-molecular-mass PAHs.     

The determination of light petroleum residues in refined oils and fats

A rapid, direct injection gas liquid chromatographic (GLC) method for determining residual light petroleum in edible vegetable oils has been developed. The response is linear at levels between 0.05–0.5 mg hexane/kg oil. A sample containing 0.2 mg hexane/kg oil was analyzed for repeatability, giving a standard deviation of 0.008 mg/kg, equivalent to a coefficient of variation of 4%. Separation of pentane, hexane, heptane, octane and decane was obtained by this method. A survey of 23 samples of freshly refined vegetable oils obtained from 13 U.K. refiners in 1981 showed that these all contained less than 0.05 mg hexane/kg oil.     

Major gaseous and PAH emissions from a fluidized-bed combustor firing rice husk with high combustion efficiency

This experimental work investigated major gaseous (CO and NO_x) and PAH emissions from a 400 kW_th fluidized-bed combustor with a cone-shaped bed (referred to as ‘conical FBC’) firing rice husk with high, over 99%, combustion efficiency. Experimental tests were carried out at the fuel feed rate of 80 kg/h for different values of excess air (EA). As revealed by the experimental results, EA had substantial effects on the axial CO and NO_x concentration profiles and corresponding emissions from the combustor. The concentration (mg/kg-ash) and specific emission (μg/kW h) of twelve polycyclic aromatic hydrocarbons (PAHs), acenaphthylene, fluorene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene and indeno[1,2,3-cd]pyrene, were quantified in this work for different size fractions of ash emitted from the conical FBC firing rice husk at EA = 20.9%. The total PAHs emission was found to be predominant for the coarsest ash particles, due to the effects of a highly developed internal surface in a particle volume. The highest emission was shown by acenaphthylene, 4.1 μg/kW h, when the total yield of PAHs via fly ash was about 10 μg/kW h.     

溶剂效应对脱除煤沥青中3,4-苯并芘的影响

研究了单种溶剂、混合溶剂对3,4-苯并芘的溶解选择性及煤沥青溶解量。并以顺丁烯二酸酐为改性剂、硫酸为催化剂,考察了溶剂效应对降低煤沥青中3,4-苯并芘的影响。研究表明,环己烷、甲苯,环己烷、乙酸丁酯组成的混合溶剂具有较好的3,4-苯并芘溶解选择性和合适的煤沥青溶解量。当环己烷∶甲苯=2∶1（体积比）和环己烷∶乙酸丁酯=2∶1（体积比）为反应溶剂时,能够高效地脱除煤沥青中3,4-苯并芘,煤沥青中3,4-苯并芘降低率分别达到88.26%和90.83%。其原因认为是此类溶剂能使包裹在沥青颗粒内部的3,4-苯并芘释放出来,且3,4-苯并芘与改性剂能够形成均相反应体系,大部分不具有致癌性的高相对分子质量环芳烃与改性剂之间形成两相体系,从而提高了改性剂与3,4-苯并芘的有效反应。     

POLYCYCLIC AROMATIC HYDROCARBONS (PAH) IN DANISH SMOKED FISH AND MEAT PRODUCTS

Twenty seven PAH were detected in 45 selected smoked food samples produced in Denmark, including mackerel, herring, trout, small sausages, salami, and bacon. The sum of PAH in smoked meat products ranged from 24 μg/kg for salami to 64 μg/kg in bacon, while those in fish products ranged from 22 μg/kg in smoked mackerel prepared in an electric oven to 1387 μg/kg in herring smoked by direct smoking. The concentration of benzo[a]pyrene for all sample types were below the maximum level of 5 μg/kg for smoked fish and meat set by the European Commission. Results from this survey confirm that the actual level of individual PAH in fish products is dependent on variables such as the type of wood used in the smoking process. Furthermore, the use of the benzo[a]pyrene approach for estimation of the carcinogenicity of PAH in food is confirmed. The Danish intake of benzo[a]pyrene from these smoked products is 2 to 4 ng/person/day.