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1.
在云南省曲靖市各植烟县采集代表性植烟土壤和烟叶样品各96个,测定了样品的铅、铬、汞含量,并分析了烟叶铅、铬、汞含量与土壤环境因子的相关性。结果表明:曲靖烟区烤烟铅、铬、汞平均含量分别为4.15,1.78和0.050mg/kg,均处于较低水平;土壤中铅、铬、汞含量符合国家土壤环境质量2级的样点数分别达到98.96%,100%和94.79%,土壤重金属含量状况良好;植烟土壤pH适宜,有机质含量丰富,氮素、钾素含量较高,磷素含量适中。烟叶中铅、铬、汞的含量与土壤中的含量存在直接关系,与土壤pH负相关,与土壤有机质含量正相关。  相似文献   

2.
廊坊及其周边地区羊体常见重金属残留分析   总被引:2,自引:0,他引:2  
目的:了解廊坊及其周边地区羊体、饲料、水源、土壤常见重金属污染现状。方法:采用石墨炉原子吸收分光光度法和氢化物发生器-原子吸收光谱法检测样品中铅、砷、汞、镉、铬的含量。结果:羊肉、肝脏、肾脏样品中铅、砷、镉、铬均有检出,且均无超标,汞均未检出;饲料、饮水、土壤中铅、砷、汞、镉、铬均检出,但均符合标准。结论:廊坊及其周边地区羊体内重金属含量基本处于安全水平,但有个别样品因受饲料、环境等因素的影响,重金属含量接近临界值或超标。  相似文献   

3.
部分市售茶叶中铅、铬污染状况调查   总被引:1,自引:1,他引:1  
目的了解市售茶叶中铅、铬两种重金属元素的污染状况,调查茶叶中铅、铬的本底值,为食品安全风险评估提供数据支持。方法从7个省、直辖市和自治区采集了420份茶叶样品,样品包含人们日常消费的主要茶叶品种,采用GB 5009-12-2010和GB 5009-123-2003中石墨炉原子吸收分光光度法对样品中的铅、铬两种元素的含量进行测定,依据GB 2762-2012茶叶中铅的限量和NY 659-2003中铬的限量对结果进行判定。结果茶叶中铅的检出率为90.7%,超标率为0.48%,铬的检出率为93.1%,超标率为0.71%,合格率略高或持平于2005~2009年监测结果。不同产地、不同品种、不同包装形式的茶叶之间铅铬含量存在差异。结论市售茶叶中铅、铬两种重金属元素的总体污染较低,但个别样品存在铅、铬含量超标现象,应引起适当的关注。  相似文献   

4.
为了研究土壤高含量重金属和砷在茶叶中的积累与浸出行为,选择贵州省云雾土壤高含量重金属和砷茶园,采集了土壤和茶叶样品各46个,对土壤-茶叶-茶汤系统重金属和砷进行分析。结果表明:云雾茶园土壤重金属Cd、Hg和As均有部分超出土壤二级标准限量值,超标率分别为80.4%、69.6%和8.7%,该茶园土壤存在严重的Cd和Hg污染。但是,茶叶和茶汤的重金属和砷并未超标,茶叶对不同土壤重金属和砷的富集能力为Cu>Cd>Hg>Pb>Cr>As,茶叶-茶汤系统重金属和砷浸出率最高的元素为Hg,不同重金属和砷的浸出率为Hg>As>Cu>Pb>Cd>Cr,Hg和Cu在土壤-茶叶-茶汤系统具有较大富集系数和浸出率。  相似文献   

5.
中文:目的 对山东临沂地区五个花生主产区2014年产花生真菌及黄曲霉毒素污染情况进行调查。方法 分别采集收获前1个月的花生和土壤样品、收获期、收获后贮藏1个月及3个月的花生样品,花生和土壤真菌菌相调查分别采用点种法和稀释法接种马铃薯葡萄糖琼脂(PDA)平板,于28±1℃培养5后进行菌落计数并鉴定;黄曲霉毒素含量采用高效液相色谱法测定。结果 临沂不同地区花生和土壤样品污染的真菌菌相不同,土壤样品真菌菌相更为丰富,但黄曲霉(7%)及黄曲霉毒素(1%)污染水平均较低。结论 山东临沂部分地区花生样品受黄曲霉及黄曲霉毒素污染较轻,但仍需注意土壤中其它真菌污染,可以有效预防花生中真菌及其毒素污染和减少人类膳食暴露。  相似文献   

6.
目的对山东临沂地区五个花生主产区2014年花生真菌及黄曲霉毒素污染情况进行调查。方法分别采集收获前1个月的花生和土壤样品和收获期、收获后贮藏1个月及3个月的花生样品,花生和土壤真菌菌相调查分别采用点种法和稀释法接种马铃薯葡萄糖琼脂(PDA)平板,于28±1℃培养5 d后进行菌落计数并鉴定;黄曲霉毒素含量采用高效液相色谱法测定。结果临沂不同地区花生和土壤样品污染的真菌菌相不同,土壤样品真菌菌相较为丰富,但黄曲霉(7%)及黄曲霉毒素(1%)侵染水平均较低。结论山东临沂部分地区花生样品受黄曲霉及黄曲霉毒素侵染较轻,但仍需注意土壤中其他真菌污染。  相似文献   

7.
采用田间实验,选取3块稻田种植创优华占、Y两优957、Y两优911、旺两优958、旺两优950等5个水稻品种,通过对土壤pH值、土壤和稻谷重金属Cd含量的测定,分析不同品种水稻重金属Cd吸收积累特性。结果表明:土壤在实验水稻种植期间pH值和重金属Cd含量未发生变化;水稻在三个稻田种植实验组中重金属Cd含量差异较大,Y两优911品种重金属Cd含量最低(0.101~0.228mg/kg);对不同品种稻谷重金属Cd含量进行3个聚类分析,第Ⅲ类的Y两优911和创优华占稻谷重金属Cd含量最低;在不同品种稻谷重金属Cd富集能力分析中,Y两优911重金属Cd富集能力低于其他品种(P0.01)。综上所述,水稻Y两优911品种重金属Cd吸收积累相对吸收较小,可以在中、低重金属污染农田中安全种植。  相似文献   

8.
农产品重金属污染已越来越为社会关注,为探明农作物、土壤和大气等镉污染与公路交通的关系,按不同采样距离采集高速、国道、省道和县级公路两侧农作物和土壤样品,检测Cd含量,并对高速公路路口、生活区和风景区空气自动监测站PM2.5和PM10样品中的Cd含量进行检测分析.结果表明,农作物Cd含量受公路交通影响的情况并不明显,所有监测农作物Cd含量均未超过绿色食品标准的限量规定;农作物中Cd的直接源头土壤和大气也未表现出受公路交通影响的趋势,所有采样点土壤Cd含量均在绿色食品标准的限量范围内,也无距路侧采样距离不同而发生变化的规律;高速公路出口附近PM2.5或PM10样品中Cd含量与生活小区或风景区相比无显著差异.  相似文献   

9.
目的了解厦门市市售土笋冻中铬的污染状况,探讨土笋冻中铬的污染来源及预防措施。方法 2012—2014年在厦门市各采样点随机抽取土笋冻样品81份,虫体样品9份,从宁德地区滩涂海域采集可口革囊星虫、淤泥、海水等环境样品6份,依照GB/T 5009.123—2003《食品中铬的测定》中推荐的石墨炉原子吸收光谱法测定样品中铬的含量。结果 81份土笋冻样品中铬含量范围在0.024~17.6 mg/kg之间,平均值为2.17 mg/kg,中位数为1.33 mg/kg,超标率为42.0%(34/81)。添加明胶加工后导致土笋冻中铬含量从1.33 mg/kg升至5.35 mg/kg。从宁德地区滩涂海域采集的星虫、淤泥、海水样品中铬的含量范围分别为2.67~2.70、68.5~77.9和0.038~0.046 mg/kg。结论厦门市市售土笋冻样品中铬的污染情况较为严重,监管部门须加强对土笋冻的原料、加工、销售过程的监控,保证食品安全。  相似文献   

10.
旨在对市场中销售的食品添加剂明胶及添加明胶的食品中铬含量本底调查。采用火焰原子吸收分光光度方法以及GB6783-1994中的二苯碳酰二肼分光光度法对市场中15个作为食品添加剂的明胶样品中铬含量进行测试,结果表明铬含量在1.04~249.4mg/kg,其中有2个样品符合GB6783食品添加剂明胶中的规定,仅占样品总量的13.3%,13个样品中铬含量都远大于2.0mg/kg,占样品总量的86.7%,其中10个样品中铬含量大于100mg/kg,铬的最高含量高达249.4mg/kg。应用GB/T5009.123-2003中规定的原子吸收石墨炉法对10个肉冻样品中铬的测试,结果表明,肉冻样品中铬含量在0.46~22.37mg/kg,其中4个样品小于2.0mg/kg,占样品总量的40%,其余6个样品中铬含量都大于2.0mg/kg,占样品总量的60%。最后对食品添加剂明胶生产、销售的监控以及对相应国家标准的修订提出了建议。  相似文献   

11.
目的探究冀东典型蔬菜种植区(唐山市和承德市)设施土壤重金属特征。方法对设施大棚进行调查并采集表层土壤样品,检测其重金属,即镉(Cd)、汞(Hg)、砷(As)、铅(Pb)、铬(Cr)、铜(Cu)、锌(Zn)含量,并依据HJ/T 333—2006《温室蔬菜产地环境质量评价标准》进行了土壤质量评价。结果除As外,其他重金属均超过河北省土壤背景值(国家环境保护局),最高为Hg,为背景值的3.46倍。Cd与棚龄呈显著负相关关系(P<0.05)。从地理分布来看,Hg呈现西高东低的分布特征,而As、Pb则呈现南高北低的分布特征。从重金属单项质量指数来看,Cd、Hg、As、Cr、Zn均未超标;Cu、Pb超标率分别为7.37%和22.11%,属轻度污染。从重金属综合质量指数看,3.16%的土壤为超标土壤,属轻度污染,超标率较高的区县为隆化县、乐亭县、滦平县、宽城县和滦南县,重金属综合质量指数与土壤pH呈极显著负相关关系(P<0.01)。结论冀东典型蔬菜种植区设施土壤存在Cu、Pb的轻度污染现象,后续需要对蔬菜中的Cu、Pb进行调查以评估蔬菜产品的安全性。  相似文献   

12.
Thallium transfer from naturally (pedogeochemically) contaminated soils into vegetables was studied. Three different types of top-soil (heavy, medium, and light) were used for pot experiments. The soils were collected from areas with low, medium, and high levels of pedogeochemical thallium (0.3, 1.5 and 3.3 mg kg-1). The samples of vegetables were collected and analysed. The total content of thallium in soil and the type of soil (heavy, medium and light), plant species and plant variety were found to be the main factors influencing thallium uptake by plants. The uptake of thallium from soils with naturally high pedogeochemical content of this element can be high enough to seriously endanger the food chain. These findings are very important because of the high toxicity of thallium and the absence of threshold limits for thallium in soils, agricultural products, feedstuffs and foodstuffs in most countries, including the Czech Republic.  相似文献   

13.
恩施烟区土壤养分状况调查   总被引:2,自引:0,他引:2  
通过对恩施烟区272个土壤样品所进行的测定,评价了植烟土壤养分状况。结果表明,全州90%以上被调查土壤适宜种植烟草,50%的样品有机质含量较为适宜,近35%的样品有机质含量偏高,60%土壤全氮适宜。近60%的土壤碱解氮偏高,77.65%的土壤速效磷含量适中且部分偏高,但仍然有近23%的土壤速效磷含量偏低或缺乏;60%以上被调查土壤平均速效钾含量偏低,且区域间差异较大。土壤普遍缺镁,72.06%的被调查土壤交换性镁含量低于0.4 cmol/kg,变异系数为84.51%;30.51%的被调查土壤缺硼,56.99%的土壤存在缺硼风险;全州范围内大多数土壤有效锌含量适宜,部分偏高,但含量差异大,变异系数高。  相似文献   

14.
A study was conducted to identify factors associated with the likelihood of detecting Giardia spp. and Cryptosporidium spp. in the soil of dairy farms in a watershed area. A total of 37 farms were visited, and 782 soil samples were collected from targeted areas on these farms. The samples were analyzed for the presence of Cryptosporidium spp. oocysts, Giardia spp. cysts, percent moisture content, and pH. Logistic regression analysis was used to identify risk factors associated with the likelihood of the presence of these organisms. The use of the land at the sampling site was associated with the likelihood of environmental contamination with Cryptosporidium spp. Barn cleaner equipment area and agricultural fields were associated with increased likelihood of environmental contamination with Cryptosporidium spp. The risk of environmental contamination decreased with the pH of the soil and with the score of the potential likelihood of Cryptosporidium spp. The size of the sampling site, as determined by the sampling design, in square feet, was associated nonlinearly with the risk of detecting Cryptosporidium spp. The likelihood of the Giardia cyst in the soil increased with the prevalence of Giardia spp. in animals (i.e., 18 to 39%). As the size of the farm increased, there was decreased risk of Giardia spp. in the soil, and sampling sites which were covered with brush or bare soil showed a decrease in likelihood of detecting Giardia spp. when compared to land which had managed grass. The number of cattle on the farm less than 6 mo of age was negatively associated with the risk of detecting Giardia spp. in the soil, and the percent moisture content was positively associated with the risk of detecting Giardia spp. Our study showed that these two protozoan exist in dairy farm soil at different rates, and this risk could be modified by manipulating the pH of the soil.  相似文献   

15.
目的 植物提取物作为天然植物饲料原料的代表因其具有抗氧化、抗病毒等作用得到广泛的开发与利用,随着药物饲料添加剂的退出,植物提取物越来越广泛的应用于畜禽、水产等养殖业中,所以有必要了解天然植物原料及产品中重金属的污染状况。方法 对北京、天津、黑龙江、江苏、安徽、江西、山东、河南、湖南、广东等10个省市采集的天然植物原料及产品样本,参照国标方法中的干法消解和压力罐消解方法对样品进行消解,然后使用火焰原子吸收光谱仪(FAAS)和原子荧光光谱仪(AFS)检测样品中砷、铅、铬、汞、镉的含量。结果 分析了100份植物饲料原料及产品,其中砷的最高值为8.54 mg/kg,大于2 mg/kg的样品所占比为4%;铅的最高值为20.33 mg/kg,大于10 mg/kg的样品只有2批次;铬的最高值为927.63 mg/kg,大于5 mg/kg的样品所占比为24%;汞的检出率为4%;全部样品中镉未检出。结论 本次调查分析发现部分样品有砷、铅、铬、汞检出,少数样品中的重金属含量相对较高,因而需加强对天然植物饲料原料及产品安全风险的监测,以保证动物和动物性产品安全。  相似文献   

16.
广西百色植烟土壤主要养分特征及施肥策略   总被引:10,自引:0,他引:10  
2005、2006年采集了百色市8个产烟县有代表性的植烟土壤样品236个,并进行了土壤养分含量分析。结果表明,百色市土壤pH处于适宜范围,土壤有机质较为丰富,土壤速效氮、速效磷含量较高,土壤速效钾相对缺乏,土壤交换性钙、有效硫含量丰富,土壤交换性镁含量偏低。因此,在生产过程中,要遵循控氮、适磷、提钾原则,施用生物钾肥,提高土壤有效钾含量;注意增施镁肥,提高土壤交换性镁含量。  相似文献   

17.
The aim of this study is to predict the solid-solution partitioning of heavy metals in river flood plain soils. We compared mechanistic geochemical modeling with a statistical approach. To characterize the heavy metal contamination of embanked river flood plain soils in The Netherlands, we collected 194 soil samples at 133 sites distributed in the Dutch part of the Rhine and Meuse river systems. We measured the total amounts of As, Cd, Cr, Cu, Ni, Pb, and Zn in the soil samples and the metal fraction extractable by 2.5 mM CaCl2. We found a strong correlation between heavy metal contamination and organic matter content, which was almost identical for both river systems. Speciation calculations by a fully parametrized model showed the strengths and weaknesses of the mechanistic approach. Cu and Cd concentrations were predicted within one log scale, whereas modeling of Zn and Pb needs adjustment of some model parameters. The statistical fitting approach produced better results but is limited with regard to the understanding it provides. The log RMSE for this approach varied between 0.2 and 0.32 for the different metals. The careful modeling of speciation and adsorption processes is a useful tool for the investigation and understanding of metal availability in river flood plain soils.  相似文献   

18.
2002-2009年顺义区市售农产品铅污染监测结果分析   总被引:1,自引:1,他引:0       下载免费PDF全文
目的掌握顺义区市售农产品铅污染现状。方法2002-2009年,抽检各类市售农产品包括粮食、蔬菜、水果,开展重金属铅的污染监测工作。结果获得监测数据414个,对照相关指标,市售农产品总体合格率为96.62%,其中豆类合格率最低为77.78%。结论铅在粮食中的污染情况较蔬菜和水果严重,在蔬菜中铅对鲜食用菌和叶菜的污染更为严重,顺义区市售农产品中粮食的铅污染问题应该引起重视。  相似文献   

19.
PCDD/Fs and PCBs have been analyzed in a series of archived soil samples collected from various depths during the 1800s and early 1900s. PCBs were not found in soil samples collected before 1900, whereas PCDD/Fs were present in concentrations between 43 and 110 pg/g in surface soils, and between 9 and 150 pg/g in soils collected from below the surface. The PCDD/F homologue patterns of all surface soils were consistent with each other. The homologue pattern of deeper soils altered with depth to one that was dominated by highly chlorinated PCDDs. The highest sigma(4-8)PCDD/F concentration (150 pg/g) was found in the deepest soil analyzed (230-250 cm below the surface). The cork from one of the storage bottles contained considerable quantities of both PCBs and PCDD/Fs. However, contamination of the soils, either by diffusion through the cork or by cork particles, was discounted on the basis that no PCBs were evident in the soil, and that the PCDD/F homologue pattern in the cork was very different to that found in the soil. Similar arguments were used to discount contamination of the soil by dust. A sample of ashed vegetation from the archive, that had no cork stopper, contained high concentrations of PCBs (78 ng/g), concentrations of mono- to tri-CDFs that were higher than in any of the soils (190 pg/g), but very low concentrations of sigma(4-8)PCDD/F (12 pg/g). This pattern of analytes was considered to be representative of contamination from store room air and was completely different from the pattern observed in the soils. Taken together these observations indicate that contamination during storage, or subsequent handling, is unlikely to have occurred in archived soil samples that were stored with cork and wax seal intact. The results imply surface soil sigma(4-8)PCDD/F concentrations of around 60 pg/g at Rothamsted (southeast England) in the late 1800s, compared with approximately 300 pg/g reported for rural UK soils in the 1990s.  相似文献   

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