高效液相色谱法测定稻米和稻田水土中多菌灵残留

采用高效液相色谱法测定稻米和稻田水土中的多菌灵残留，用稀盐酸溶液提取，经液液分配净化，外标法定量。多菌灵的峰面积与进样质量在0．15ng-220ng范围内呈线性相关，在稻田水、土壤和稻米中的最低检出质量比分别为0．01mg／kg、0．01mg／kg和0．02mg／kg。3个质量水平的加标回收试验结果表明，多菌灵在稻田水样中的平均回收率为87．1％～93．0％，RSD为3．3％～3．8％；在土壤中的平均回收率为84．8％-91．9％，RSD为1．4％～4．1％；在稻米中的平均回收率为83．9％～89．6％，RSD为1．8％-5．5％。     

镇江地区土壤样品中重金属Cd含量与空间分布

通过对镇江地区土壤样品中 Cd 监测结果统计分析表明，全市69个样品中 Cd 质量比范围为0．06 mg/kg ～1．37 mg/kg，均值为0．23 mg/kg，与全国背景值相比，有一定程度富集；样品中 Cd 质量比成偏态分布，相对标准偏差较大。选用单项污染指数法对 Cd污染程度评价表明，镇江地区83％的土壤样品未受到 Cd 污染，14％为轻度污染，3％为中度污染。结合镇江地区的产业结构分析，电镀行业是土壤 Cd 污染的主要来源，道路运输、农药化肥在一定程度上也加重了污染。     

佳木斯市土壤中酞酸酯类污染调查及评价

对佳木斯市农业土壤中酞酸酯类污染物含量进行了调查。在佳木斯市市区及6个县市采集土壤样品184个进行分析。监测结果表明，土壤中酞酸酯浓度（∑PAEs）为未检出～10298．9μg／kg，检出率为89．1％。DEHP为主要污染物，检出率为88．0％，均值为1999．2μg／kg，最高浓度为8577．4μg／kg。DMP检出率最低，为0．5％。     

微波消解-氢化物发生原子荧光法测定植物中汞和砷

采用微波消解-氢化物发生原子荧光法测定植物中汞和砷，优化了试验条件。汞在0μg／L-1．00μg／L、砷在0μg／L～20．0μg/L范围内线性良好，方法检出限汞为0．005mg／kg（以取0．1g样品消解定容至10mL计），砷为0．010mg／kg（以取0．1g样品消解定容至25mL计），植物样品测定的RSD≤4．5％，加标回收率为90．0％～107％。     

气相色谱/质谱法测定环境毒饵中溴敌隆

采用气相色谱／质谱联用法测定环境毒饵中溴敌隆，优化了试验条件。方法在0mg／L～10．0mg／L范围内线性良好，检出限为0．01mg／kg，标准溶液测定的相对标准偏差为2．2％～4．6％，样品加标回收率为92．5％-96．3％。     

上海市城区典型居民住宅区PM2.5和PM10监测结果比较研究

在上海市环境空气质量连续自动监测网络中的一个城市居民住宅区监测点进行了为期一年的PM2.5和PM10的同步监测，监测结果表明：PM2.5和PM10日平均浓度之间的比值范围为0．194～0．889，月平均浓度之间的比值范围为0．420～0．667；冬季颗粒物中小粒径颗粒物PM2.5的比例较高，春季则较低；随着相对湿度的上升；颗粒物中小粒径颗粒物PM2.5的比例缓慢升高；比值变化的风向特征与监测点周围环境情况有关；PM2.5和PM10监测结果月均值之间和各月的日均值之间均线性相关，回归直线关系存在。     

高效液相色谱法测定土壤中三嗪类除草剂

建立了索氏提取、中性氧化铝小柱净化、高效液相色谱二极管阵列检测器测定土壤中7种三嗪类除草剂的方法，优化了检测波长、提取方法和溶剂、梯度淋洗程序等试验条件。7种三嗪类除草剂在0．10mg／L～2．00mg／L范围内线性良好，检出限为0．84μg／kg～2．07μg／kg，RSD为1．2％～5．6％，加标回收率为95.0％～107％。     

偏振能量色散X射线荧光光谱法测定土壤中金属元素

建立了偏振能量色散X射线荧光光谱同时测定土壤中6种金属元素的方法，优化了试验条件。方法线性良好，Cr、Mn、Pb、Cu、As、Se的检出限分别为3．62mg／kg、3．65mg／kg、0．91mg／kg、0．23mg／kg、0．35mg／kg、0．01mg／kg，土壤标准样品的测定结果均符合要求，实际样品测定的RSD为0．5％～10．0％，与原子吸收法、原子荧光法的测定结果相吻合。     

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。     

固相膜萃取-高效液相色谱法测定地下水中的多环芳烃

采用C18固相膜萃取对地下水中15种多环芳烃进行富集净化，以二氯甲烷作洗脱溶剂，高效液相色谱法，荧光检测器测定。对萃取、浓缩和色谱条件进行优化，在1．ooixg／L～40．0μg／L范围内测定标准系列溶液并绘制标准曲线，相关系数R2〉0．999；15种多环芳烃的仪器检出限为0．4ng／L～3．0ng／L；对地下水样品加标，平均回收率在75．7％～96．7％之间；标准溶液平行测定7次的RSD为3．1％～11．9％。     

Outdoor 220Rn, 222Rn and terrestrial gamma radiation levels: investigation study in the thorium rich Fen Complex, Norway

The present study was done in the Fen Complex, a Norwegian area rich in naturally occurring radionuclides, especially in thorium ((232)Th). Measurement of radioactivity levels was conducted at the decommissioned iron (Fe) and niobium (Nb) mining sites (TENORM) as well as at the undisturbed wooded sites (NORM), all open for free public access. The soil activity concentrations of (232)Th (3280-8395 Bq kg(-1)) were significantly higher than the world and the Norwegian average values and exceeded the Norwegian screening level (1000 Bq kg(-1)) for radioactive waste, while radium ((226)Ra) was present at slightly elevated levels (89-171 Bq kg(-1)). Terrestrial gamma dose rates were also elevated, ranging 2.6-4.4 μGy h(-1). Based on long-term surveys, the air concentrations of thoron ((220)Rn) and radon ((222)Rn) reached 1786 and 82 Bq m(-3), respectively. Seasonal variation in the outdoor gamma dose rates and Rn concentrations was confirmed. Correlation analyses showed a linear relationship between air radiation levels and the abundance of (232)Th in soil. The annual outdoor effective radiation doses for humans (occupancy 5 h day(-1)) were estimated to be in the range of 3.0-7.7 mSv, comparable or higher than the total average (summarized indoor and outdoor) exposure dose for the Norwegian population (2.9 mSv year(-1)). On the basis of all obtained results, this Norwegian area should be considered as enhanced natural radiation area (ENRA).     

Assessment of public exposure to naturally occurring radioactive materials from mining and mineral processing activities of Tarkwa Goldmine in Ghana

Studies have been carried out in a Goldmine in Ghana to determine the exposure of the public to naturally occurring radioactive materials from processing of gold ore. Direct gamma spectrometry and neutron activation analysis techniques were used to analyse soil, rock, water and dust samples from the mining environment. The mean activity concentrations measured for (238)U, (232)Th and (40)K in the soil/rock samples were 15.2, 26.9 and 157.1 Bq kg(?-?1), respectively. For the water samples, the mean activity concentrations were 0.54 and 0.41 Bq l(?-?1)) and 7.76 Bq l(?-?1) for (226)Ra, (232)Th and (40)K, respectively. The mean activity concentrations measured in the dust samples were 4.90 and 2.75 μBq m(?-?3) for (238)U and (232)Th, respectively. The total annual effective dose to the public was estimated to be 0.69 mSv. The results in this study compared well with typical world average values. The results indicate an insignificant exposure of the public from the activities of the Goldmine.     

Uranium bioassay and radioactive dust measurements at some uranium processing sites in Egypt--health effects

The safety of radiation workers in the uranium mining industry requires close and continuous monitoring of their working conditions. In this study, external radiation surveillance, radioactive dust monitoring and the bioassay of uranium were carried out in some processing sites. As dust represents one of the most important sources of radiation exposure in mills and mines, dust monitoring and bioassays were performed for a sample of workers on the production lines. The concentration of uranium in air ranged from 22.6 x 10(-7) to 11.1 x 10(-5) Bq cm-3, and the exposure levels ranged from 1 to 80 microSv h-1. Laser fluorimetric determination of uranium in urine samples showed concentrations in the range 8.4-29.2 micrograms L-1. Renal function parameters, such as serum creatinine and urea, and hematological parameters were determined in an attempt to correlate them with radiation exposure and the health status of the workers. Urine specimens collected from workers at the ore crushing and separation site showed elevated concentrations of uranium (up to 29.2 micrograms L-1) and a strong correlation between these concentrations and the registered serum creatinine. The mean uranium excretion in the investigated group was more than 20 times the occupational exposure decision level for urine uranium of 0.8 microgram L-1.     

226Ra, 232Th and 40K analysis in soil samples from some areas of Malwa region, Punjab, India using gamma ray spectrometry

The activity concentrations of soil samples collected from thirty different locations of Malwa region of Punjab were determined by using HPGe detector based on high-resolution gamma spectrometry system. The range of activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K in the soil from the studied areas varies from 18.37 Bq kg⁻¹ (Sangrur) to 53.11 Bq kg⁻¹ (Sitoguno), 57.28 Bq kg⁻¹ (Dhanola) to 148.28 Bq kg⁻¹ (Sitoguno) and 211.13 Bq kg⁻¹ (Sunam) to 413.27 Bq kg⁻¹ (Virk Khera) with overall mean values of 35 Bq kg⁻¹, 80 Bq kg⁻¹and 317 Bq kg⁻¹ respectively. The absorbed dose rate calculated from activity concentration of ²²⁶Ra, ²³²Th and ⁴⁰K ranges between 8.47 and 24.48, 35.68 and 92.38, and 8.74 and 17.11 nGy h⁻¹, respectively. The total absorbed dose in the study area ranges from 58.08 nGy h⁻¹ to 130.85 nGy h⁻¹ with an average value of 79.11 nGy h⁻¹. The calculated values of external hazard index (H_ex) for the soil samples of the study area range from 0.35 to 0.79. Since these values are lower than unity, therefore, according to the Radiation Protection 112 (European Commission. Radiation Protection 112 1999) report, soil from these regions is safe and can be used as a construction material without posing any significant radiological threat to population.     

Indoor radon/thoron levels and inhalation doses to some populations in Himachal Pradesh, India

It is well established that some areas of Himachal Pradesh (H.P.) state of India situated in the environs of the Himalayan mountains are relatively rich in uranium-bearing minerals. Some earlier studies by our group have indicated high levels of radon (>200 Bq m(-3)) in the dwellings. It is in this context that an indoor radon/thoron survey has been carried out in selected villages of four districts in the state of H.P. This survey has been conducted as a part of a national, coordinated project using twin chamber dosemeter cups designed by the Environmental Assessment Division (EAD), Department of Atomic Energy, Govt. of India. The track-etch technique is used for calibration of plastic detector LR-115 type-II which are employed for recording alpha tracks due to radon/thoron and their daughters. Year long radon/thoron data have been collected for seasonal correlations of indoor radon/thoron in the dwellings. The indoor radon levels have been found to vary from a minimum value of 17.4 Bq m(-3) to a maximum value of 140.3 Bq m(-3). The indoor thoron levels vary from a minimum value of 5.2 Bq m(-3) to a maximum value of 131.9 Bq m(-3). The year average dose rate for the local population varies from 0.03 microSv h(-1) to 0.83 microSv h(-1). The annual exposure dose to inhabitants in all the dwellings lies below the upper limit of 10 mSv given in ICRP-65.     

哈密建材中镭—226,钍—232,钾—40含量及所致居民剂量评价

用放射化学分析方法对哈密地区109份建材中天然放射性核素镭-226、钍-232、钾-40含量进行分析测定.结果表明,内、外照射指数分别为0.04-0.38和0.08-0.67,炉渣和花岗岩石最高,大理石和石灰、石膏最低.混合建材中镭-226、钍-232、钾-40含量(Bq/ kg)分别为 43.8, 40.0,594.0.建材所致居民内、外照射年有效剂量当量为 0.70mSv/ a,是我国《放射卫生防护基本标准》中规定公众个人年剂量当量限值5mSv的14.0％,不会对广大居民的健康造成有害的影响.     

Distributions of 210Pb around a uraniferous coal-fired power plant in Western Turkey

In the present study the spatial and the vertical distributions of 210Pb were investigated in the soils around a uranifereous coal fired power plant (CPP) in Yatagan Basin, in Western Turkey. The variation of 226Ra activity along the soil profiles was studied to assess the unsupported 210Pb distribution in the same samples. 226Ra was measured by gamma spectroscopy and 210Pb activities were determined from 210Po activities using radiochemical deposition and alpha spectroscopy. The total 210Pb activity concentrations in bulk core samples varied in the range of 38-250 Bq kg(-1) in the study sites and of 22-78 Bq kg(-1) in reference site. In the sectioned cores sampled from the study areas the ranges for activity concentrations of 226Ra, total 210Pb and unsupported 210Pb are 24-77; 39-344 and 4-313 Bq kg(-1), respectively. Corresponding ranges for reference site are 37-39; 39-122 and 1-83 Bq kg(-1).     

Gross alpha and beta radioactivity concentration in water, soil and sediment of the Bendimahi River and Van Lake (Turkey)

The concentrations of the natural radioactivity in water, soil and sediment samples collected from Bendimahi River which originates near the Tendürek Mountain (Van, Turkey), its tributaries and Van Lake (Turkey) were measured. The gross-alpha and gross-beta radioactivity concentrations were investigated in May and August in 2005. Determination of the gross-alpha and gross-beta radioactivity of river water, soil and sediment samples was obtained by using gas-flow proportional counter, PIC-MPC 9604-alpha/beta counter. In water samples, the obtained results show that in May; gross-alpha and gross-beta activity concentrations varied between 0.063-0.782 and 0.021-0.816 Bq l(-1) and in August the values were 0.009-0.037 and 0.081-3.116 Bq l(-1), respectively. The gross-alpha and gross-beta activity concentrations in soil samples ranged from 0.800 to 4.277 Bq g(-1) and 0.951 to 11.773 Bq g(-1) in May and 0.686 to 4.713 Bq g(-1) and 0.073 to 9.524 Bq g(-1) in August, respectively. Concentrations ranging from 0.782 to 4.596 Bq g(-1) and from 0.482 to 10.372 Bq g(-1) in May and from 0.580 to 5.824 Bq g(-1) and from 0.303 to 9.702 Bq g(-1) in August for gross-alpha and gross-beta radioactivity were observed in sediments, respectively.     

Geochemical and radionuclide profile of Tuzla geothermal field, Turkey

Tuzla geothermal basin is situated in north-western Turkey on the Biga Peninsula, which is located at the west end of the Northern Anatolian Fault system. Soil and water samples were collected between August 2003 and June 2004 to initiate development of a geochemical profile of surface and subsurface waters in the geothermal basin and radionuclide concentrations in soils. All water samples were found to fall within Turkish Water Quality Class 4, meaning they were remarkably contaminated for any water consumption sector (industrial, human use or agricultural) based on sodium and chloride ions. Such waters could be used only after appropriate water treatment. The water samples are of the chloride type in terms of geochemical evaluation. Preliminary geochemical evidence shows that the N-S flowing part of the Tuzla River acts as a natural barrier within the basin. Heavy metal concentrations in the soil samples show slight elevations, especially those obtained from the east part of the basin where thermal springs are dominant. Geochemical calculations were carried out with PHREEQC software to determine equilibrium concentration of chemical species and saturation indices, by which it is suggested that chloride is the most important ligand to mobilize the heavy metals in the studied system. In addition, the activity concentration and gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides were determined in the soil using gamma-ray spectrometry. The soil activity ranged from 42.77 to 988.66 Bq kg(-1) (averaging 138 Bq kg(-1)) for ( 238 )U, 13.27 to 106.31 Bq kg(-1) (averaging 32.42 Bq kg(-1)) for ( 232 )Th, and 99.28 to 935.36 Bq kg(-1) (averaging 515.44 Bq kg(-1)) for ( 40 )K. The highest value of ( 238 )U was found in the soil samples obtained from an area close to the hot spring.     

Assessment of radionuclide and metal contamination in a thorium rich area in Norway

The Fen Central Complex in southern Norway, a geologically well investigated area of magmatic carbonatite rocks, is assumed to be among the world largest natural reservoirs of thorium ((232)Th). These rocks, also rich in iron (Fe), niobium (Nb), uranium ((238)U) and rare earth elements (REE), were mined in several past centuries. Waste locations, giving rise to enhanced levels of both radionuclides and metals, are now situated in the area. Estimation of radionuclide and metal contamination of the environment and radiological risk assessment were done in this study. The average outdoor gamma dose rate measured in Fen, 2.71 μGy h(-1), was significantly higher than the world average dose rate of 0.059 μGy h(-1). The annual exposure dose from terrestrial gamma radiation, related to outdoor occupancy, was in the range 0.18-9.82 mSv. The total activity concentrations of (232)Th and (238)U in soil ranged from 69 to 6581 and from 49 to 130 Bq kg(-1), respectively. Enhanced concentrations were also identified for metals, arsenic (As), lead (Pb), chromium (Cr) and zinc (Zn), in the vicinity of former mining sites. Both radionuclide and heavy metal concentrations suggested leaching, mobilization and distribution from rocks into the soil. Correlation analysis indicated different origins for (232)Th and (238)U, but same or similar for (232)Th and metals As, Cr, Zn, nickel (Ni) and cadmium (Cd). The results from in situ size fractionation of water demonstrated radionuclides predominately present as colloids and low molecular mass (LMM) species, being potentially mobile and available for uptake in aquatic organisms of Norsj? Lake. Transfer factors, calculated for different plant species, showed the highest radionuclide accumulation in mosses and lichens. Uptake in trees was, as expected, lower. Relationship analysis of (232)Th and (238)U concentrations in moss and soil samples showed a significant positive linear correlation.