农药厂周边有机磷农药在生物体中残留的检测方法研究

测定南京某农药厂附近大米、蔬菜及肉类中11种有机磷农药含量，通过使用气相色谱/质谱联用的方法，建立GC／MS定性定量分析方法，检出限达到0．05μg／kg（肉类）和0．1μg／kg（大米和蔬菜），回收率均符合测定要求。环境样品监测结果显示，大米和蔬菜中有机磷农药的含量高于肉类中的含量，说明在大米和蔬菜表面残留的农药量要高于进入生物体体内的含量。南京蔬菜样品中有机磷农药高于常州蔬菜样品，说明农药厂对蔬菜表面残留农药量有影响。不同的有机磷农药在不同的介质中，检出情况不一样，说明不同的环境介质对有机磷农药的保留水平不一样。     

兰州市郊蔬菜基地土壤及蔬菜中有机农药污染现状调查

通过对兰州市郊蔬菜基地土壤及蔬菜中，有机磷和有机氯农药残留量的测定，对其污染现状进行了综合分析。     

淮安市农产品中重金属及有机氯、有机磷农药残留量调查

淮安市环境监测中心站于1999年－2000年对淮安市农产品中重金属以及有机氯、有机磷农药残留量进行了调查。结果表明，粮食和蔬菜作物中，六六六的4种同分异构体只有γ－六六六能检出，检出率分别为24．0％和51．7％，都未超标；DDT的4种同分异要体均未检出；有机磷农药的检出率分别为5％和25％，其中蔬菜中敌敌畏含量出现个别超标现象，倍硫磷、乐果和杀螟松在粮食和蔬菜作物中的含量都不超标。重金属中金属“五毒”在粮食和蔬菜作物中，只有Cr和Pb能检出，Cd、Hg和As都未检出，Cu、Zn和Mn能检出，但不超标。提出，应严格按照农牧渔业部和卫生部颁发的《农药安全使用规定》用药，多使用高效低残留量的“绿色农药”；农业、环保和卫生部门必须加强合作，对蔬菜生产销售的全过程进行监督监测，以确保生产无公害蔬菜。     

气相色谱法快速测定蔬菜中灭杀毙

用蒸馏水一次提取新鲜蔬菜样品，以SE－30和QF－1为固定液，Chromosorb W AW DMCS为固定相，2m填充柱分离，氢火焰检测器检测，进样10uL测定灭杀毙含量，以保留时间定性，外标法定量，分析时间小于150s，方法回收率95．4％，相对标准差3．6％，可用作上市蔬菜灭杀毙农药残留量的快速测定。     

GC-MS法测定多种有机磷农药残留

以HP-35MS色谱柱代替传统的HP-5MS色谱柱,试验了蔬菜、水果中多种有机磷农药残留的气-质联用快速检测方法。采用选择离子扫描(SIM)模式,根据保留时间和特征离子丰度比,可在40 m in内定性和定量检测30种有机磷农药残留。通过对蔬菜、水果等样品多次试验验证,添加量为0.01μg~1.00μg时,回收率在79.5%~106%之间,相对标准偏差<10%,检出限为6.6×10-10g~8.7×10-9g,均比使用HP-5MS色谱柱有所改善。     

贵州遵义地区土壤中有机氯农药残留调查

于2008年3月-5月对遵义地区土壤中有机氯农药残留进行了调查。结果表明，15种有机氯农药在所有样品中都有不同程度的检出。HCHs、DDTs类物质的检出率分别为90．7％、45．7％。∑HCH残留量为未检出～12．7μg／kg，平均值为1．6μg／kg；2DDT残留量为未检出-239．7μg／kg，平均值为2．8μg／kg；总有机氯杀虫剂平均残留量为4．51μg／kg，同国内其他地区相比，其残留水平偏低。     

气相色谱法测定土壤中37种有机磷农药残留

采用气相色谱法测定土壤中37种有机磷农药,当取样量为10 g时,37种有机磷农药方法检出限为0. 002～0. 015 mg/kg,测定下限为0. 008～0. 060 mg/kg。低含量加标样品中有机磷农药的加标回收率为72. 8%～104%,相对标准偏差为4. 2%～13. 8%;中含量加标样品中有机磷农药的加标回收率为71. 5%～101%,相对标准偏差为4. 3%～13. 5%;高含量加标样品中有机磷农药的加标回收率为74. 6%～109%,相对标准偏差为6. 8%～14. 6%。该方法灵敏度高、分离效果好、重现性好,能够满足土壤中37种有机磷农药残留检测的要求。     

固相净化气相色谱法测定水产品中多种有机磷农药残留

建立了水产品中8种有机磷农药残留同时测定的方法，选择乙腈提取，ENVI-C18串联PSA固相萃取柱净化，经丙酮/正己烷混合溶液（体积比1∶1）洗脱，洗脱液氮吹浓缩后采用气相色谱外标法定量。8种有机磷农药在0.050 mg/L～1.00 mg/L范围内线性良好，检出限在1.8 μg/kg～2.5 μg/kg之间，3个添加水平加标样品平行测定的相对标准偏差为1.1%～5.7%，回收率为69.8%～116%。     

气相色谱-串联质谱法测定水中痕量有机磷农药和甲萘威

采用二氯甲烷萃取水样，气相色谱-串联质谱法同时测定水中有机磷农药和甲萘威。试验表明：方法在20．0μg/L ～1000μg/L范围内，各目标化合物线性良好；方法检出限为0．004μg/L～0．01μg/L；对实际水样进行3个质量浓度水平的加标回收试验，回收率在71．8％～94．5％之间，RSD为3．7％～8．5％，满足水中痕量有机磷农药和甲萘威的测定要求。     

气相色谱法测定蔬菜中有机农磷药残留量

当前我区施用有机磷农药极为普遍。用作蔬菜杀虫剂的有十种之多。用量较大的是敌敌畏、乐果、氧化乐果、甲基对硫磷、对硫磷等五种。所以对蔬菜中有机磷农药残留的测定将成为常规分析。有机磷农药的分析方法有许多文献报导:比色法、极谱法、紫外分光光度法等。这些方法常用于单种有机磷农药成份的分析。薄层色谱法虽可分离多种有机磷农药,与气相色谱法相比定量精度差。后者则有选择性强,灵敏度高等特点。     

Varying Stable Nitrogen Isotope Ratios of Different Coastal Marsh Plants and Their Relationships with Wastewater Nitrogen and Land Use in New England, USA

The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ ¹⁵N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ ¹⁵N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ ¹⁵N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ ¹⁵N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ ¹⁵N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R ² = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ ¹⁵N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ ¹⁵N of Spartina relates with the integrated, watershed-sea nitrogen inputs.     

Development of simple and sensitive spectrophotometric method for the determination of bendiocarb in its formulations and environmental samples

Facile, selective and sensitive spectrophotometric method has been developed for the determination of bendiocarb in its insecticidal formulations, fortified water, food grains, agriculture wastewater and agriculture soil samples with prepared reagents. The method was based on alkaline hydrolysis of the bendiocarb pesticide, and the resultant hydrolysis product of bendiocarb was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with λmaxof457 nmorcouplingwith2, 6−dibromo−4−nitroanilinetoproducearedcoloredproductwithλ_max of474~nmorcouplingwith2, 4, 6−tribromoanilinetoformorangeredcoloredproducthasaλ_max of465 nm.Underoptimalconditions, Beer'slawrangefor2, 6−dibromo−4−methylaniline(DBMA)wasfoundtobe0.6−−14.0~μgmL ^-1, 0.8−−10.0 μgmL ^-1 for2, 6−dibromo−4−nitroaniline(DBNA)and0.4−−10.0 μgmL ^-1 for2, 4, 6−tribromoaniline(TBA).Themolarabsorptivityofthecolorsystemswerefoundtobe4.126~×~10⁴ lmol ^-1 cm ^-1 forDBMA, 3.254×10⁴ l~mol ^-1 cm ^-1 forDBNAand2.812×10⁴ lmol ^-1 cm ^-1 forTBA.Sandell'softhecolorreactionsare0.018 μgcm ^-2(DBMA), 0.052 μgcm ^-2(DBNA)and0.065 μgcm ^-2$ (TBA) respectively. The effect of the non-target species on the determination of bendiocarb was studied. The formation of colored derivatives with the coupling agents is instantaneous and stable for 18 h, 30 h, and 12 h. Performance of the proposed methods were compared statistically in terms Student's F and t-tests with the reported methods.     

Atmosphic pollutants study of particles ionic species during high wind speed (>7 m s-1) near Taiwan strait in central Taiwan from 2004 to 2005

This study monitored atmospheric pollutants during high wind speed (> 7 m s⁻¹) at two sampling sites: Taichung Harbor (TH) and Wuci traffic (WT) during March 2004 to January 2005 in central Taiwan. The correlation coefficient (R ²) between TSP, PM_2.5, PM_2.5−10 particle concentration vs. wind speed at the TH and WT sampling site during high wind speed (< 7 m s⁻¹) were also displayed in this study. In addition, the correlation coefficients between TSP, PM_2.5 and PM_2.5−10 of ionic species vs. high wind speed were also observed. The results indicated that the correlation coefficient order was TSP > PM_2.5−10 > PM_2.5 for particle at both sampling sites near Taiwan strait. In addition, the concentration of Cl⁻, NO₃ ⁻, SO₄ ²⁻, NH₄ ⁺, Mg²⁺, Ca²⁺ and Na⁺ were also analyzed in this study.     

电力跨区域调配隐含的污染转移效应

为研究中国30个省/自治区/直辖市之间电力区域调配的污染物转移效应,构建了电力传输的污染转移模型,并以SO_2和NO_x为例对2006、2015年数据进行测算。结果表明,2015年电力行业SO_2、NO_x排放强度分别由2006年的4.03、2.18 g/(kW·h)下降到0.69、0.77 g/(kW·h)。2015年,16个电力净输入区通过电力跨区域传输的SO_2、NO_x转移量分别为47.8×10~4、53.0×10~4t,占这些地区电力行业SO_2、NO_x排放量的24.1%、24.2%;14个电力净输出区通过电力跨区域传输的SO_2、NO_x转移量分别为-54.6×10~4、-52.1×10~4t,占这些地区电力行业SO_2、NO_x排放量的26.5%、22.8%。研究结果对于分析区域物质流动所隐含的污染流动,全面认识区域污染物排放格局,制定合理的区域污染减排目标具有一定借鉴意义。     

Effects of Ageing and Microbial Component on Chemical Availability of 137Cs in a Long-term Experimental Site

A loamy soil contaminated with ¹³⁷CsCl 40 years ago was investigated by a sequential extraction technique to determine the effect of ageing on chemical availability of ¹³⁷Cs. The soil samples were sequentially extracted with H₂O, NH₄Ac, NH₂OH·HCl, H₂O₂, and HNO₃. Extractability of ¹³⁷Cs decreased in the order: HNO₃ > Residual > H₂O₂ > NH₄Ac > NH₂OH·HCl > H₂O. Only 0.94% in labile fractions (H₂O and NH₄Ac), while more than 96% was found in the strongly bound fraction (HNO₃ and residual). However, the activity percentage in labile fractions was increased to 1.34% after autoclaving treatment, while those in the other fractions did not significantly differ. This indicates that the microbial activity played a role in the ¹³⁷Cs retention. In the subsequent pot experiments with ryegrass and leek, specific activities in both plants were significantly higher in autoclaved soil than in non-autoclaved soil, and uptake of ¹³⁷Cs in the five cuts by ryegrass was 25% of the labile ¹³⁷Cs in the soil. In addition, a positive correlation was found between the amount of ¹³⁷Cs in labile fractions and that by plant uptake.     

Chemistry of fogs at Agra, India: Influence of soil particulates and atmospheric gases

Fog water samples were collected in the months of December and January during 1998–2000 at Agra, India. The samples were analyzed for pH, major anions (F⁻, Cl⁻, SO₄ ²⁻, NO₃ ⁻, HCOO⁻ and CH₃COO⁻), major cations (Ca²⁺, Mg²⁺, Na⁺ and K⁺) and NH₄ ⁺ using ion chromatography, ICP-AES and spectrophotometer methods, respectively. pH of fog water samples ranged between 7.0 and 7.6 with a volume weighted mean of 7.2, indicating its alkaline characteristic. NH₄ ⁺ contributed 40%, SO₄ ²⁻ and NO₃ ⁻ accounted for 28%, while Ca²⁺, Mg²⁺, Na⁺ and K⁺ accounted for 16% of the total ionic concentration. The ratios of Mg²⁺/Ca²⁺ and Na⁺/Ca²⁺ in fog water indicates that 50–75% of fog water samples correspond to the respective ratios in local soil. Significant correlation between Ca²⁺, Mg²⁺, Na⁺ and K⁺ suggests their soil origin. The order of neutralization, NH₄ ⁺ (1.4) > Ca²⁺ (0.28) > Mg²⁺ (0.12), indicates that NH₄ ⁺ is the major neutralizing species. Fog water and atmospheric alkalinity were also computed and were found to be 873 and 903 neqm⁻³, respectively. Both of these values are higher than values reported from temperate sites and thus indicate that at the present level of pollutants, there is no risk of acid fog problem. The study also shows that the alkaline nature of fog water is due to dissolution of ammonia gas and partly due to interaction of fog water with soil derived aerosols.     

Radionuclide Concentrations in Benthic Invertebrates from Amchitka and Kiska Islands in the Aleutian Chain, Alaska

Concentrations of 13 radionuclides (¹³⁷Cs, ¹²⁹I, ⁶⁰Co, ¹⁵²Eu, ⁹⁰Sr, ⁹⁹Tc, ²⁴¹Am, ²³⁸Pu, ^239,249Pu, ²³⁴U, ²³⁵U, ²³⁶U, ²³⁸U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were ¹³⁷Cs, ²⁴¹Am, ^239,249Pu, ²³⁴U, ²³⁵U, ²³⁶U, and ²³⁸U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for ¹³⁷Cs; octopus was the only species with detectable levels of ¹³⁷Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in ²⁴¹Am and ^239,240Pu, and almost no samples above the MDA for ²³⁸Pu and ²³⁶U. Horse mussels had significantly higher concentrations of ²³⁴U (0.844 ± 0.804 Bq/kg) and ²³⁸U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.     

Three-year monitoring results of nitrate and ammonium wet deposition in Thailand

Wet deposition is one of the important sources of nitrogen input into the ecosystem. It also contributes to rain acidity in some environments. In this study we reported the annual as well as seasonal trends of nitrogen wet deposition at three locations in Thailand: Bangkok, Chiang Mai and Nan. Comparison of nitrogen wet deposition between in rural and in the urban areas was also made. Daily rainfall was measured and monthly rainwater was collected for nitrogen analysis during 1999–2002. The average NO₃ ^– concentration in rainwater collected from the rural sites (60 km from urban area) was around 0.2–0.3 mg L^–1, while that from the urban areas of Chiang Mai and Nan cities it was 0.4–0.5 mg L^–1. NH₄ ⁺ concentration in rainwater showed the similar ranges to that of NO₃ ^– , except at Nan where concentration was not significantly different between the urban and rural sites. On the other hand, the average concentrations of NO₃ ^– were higher at Bangkok site than other sites, while concentration of NH₄ ⁺ was almost the same between Chiang Mai and Bangkok. Wet deposition of NO₃ ^– at the rural sites of Chiang Mai and Nan ranged from 2.1 to 3.2 kg N ha^–1 yr^–1, while at the urban sites this ranged from about 6 kg N ha^–1 yr^–1 in Chiang Mai and Nan Cities to 8.6 kg N ha^–1 yr^–1 in Bangkok. Wet deposition of NH₄ ⁺ at the rural sites of Chiang Mai and Nan was about 2.4 to 3.6 kg N ha^–1 yr^–1 and at the urban sites of Chiang Mai, Nan and Bangkok this was 7.7, 4.9 and 8.1 kg N ha^–1 yr^–1, respectively. Thus, it was concluded that wet deposition of both nitrogen species was significantly higher at the urban sites than at the rural sites.     

Monitoring of Criteria Air Pollutants in Bursa, Turkey

The concentrations of criteria air pollutants such as CO, NO_x (NO + NO₂), SO₂ and PM were measured in the period of May 2001 and April 2003 in the city of Bursa, Turkey. The average concentrations for this period were 1115±1600 μg/m³, 29±50 μg/m³, 51±24 μg/m³, 79±65 μg/m³, 40±35 μg/m³, 98±220 μg/m³, for CO, NO, NO₂, NO_x, SO₂ and PM, respectively. Temporal changes in concentrations were analyzed using meteorological factors. Correlations among pollutant concentrations and meteorological parameters showed weak relations nearly in all data. Lower concentrations were observed in the summer months while higher concentrations were measured in the winter months. The increase in winter concentrations was probably due to residential heating. Pollutants were associated with each other in order to have information about their origin. NO_x/SO₂ ratio was also examined to bring out the source origin contributing on air pollution (i.e., traffic or stationary).     

北京市典型重污染过程中PM2.5载带水溶性无机离子污染特征分析

为研究北京地区冬季PM_(2.5)载带的水溶性无机离子组分污染特征,2013年1月在中国环境科学研究院内采用在线离子色谱(URG-9000B,AIM-IC)对PM_(2.5)中水溶性无机离子(SO_4~(2-)、NO_3~-、Cl~-、NH_4~+、Na~+、K~+、Mg~(2+)、Ca~(2+))进行监测与分析。结果表明,采样期间总水溶性无机离子(TWSI)浓度为61.0μg/m~3,其中二次无机离子SO_4~(2-)、NO_3~-、NH_4~+(SNA)占比达72.3%,在PM_(2.5)中占比为40.29%,表明北京市PM_(2.5)二次污染严重。重污染天[NO_3~-]/[SO_4~(2-)]表明,固定源污染较移动源更为显著。三元相图表明,在空气质量为优的情况下,NH_4~+(在SNA中占比为30.3%~65.5%,下同)主要以NH_4NO_3的形式存在,较少比例以(NH_4)_2SO_4存在;严重污染时,NH_4~+(47.3%~77.9%)主要以(NH_4)_2SO_4形式存在,其次以NH_4NO_3的形式存在,其余的NH_4~+以NH_4Cl的形式存在。[NO_3~-]/[SO_4~(2-)]日变化表明,早、晚机动车高峰影响北京重污染发生。