包头市蔬菜作物中农药残留状况的研究

本文探讨了包头市近郊大田蔬菜作物中28种农药的残留状况,调查了农药的使用情况,研究了有机磷、有机氯和部分菊酯类农药的分析检测方法,建立了蔬菜作物液液萃取加弗罗里硅土柱净化的前处理方法。给出了蔬菜作物的农药残留水平,对蔬菜种植过程中农药残留的检测提供了可靠的分析方法。     

滇池湖滨蔬菜种植区土壤污染物生态风险评价

选取典型滇池湖滨蔬菜种植区——昆明福保村为研究对象,进行土壤污染物生态风险分析,结合污染物空间分布规律研究,解析污染物来源。结果表明,土壤多环芳烃（Polycyclic Aromatic Hydrocarbons,PAHs）、有机氯（Organic Chlorine Pesticides,OCPs）、酞酸酯（Phthalic Acid Esters,PAEs）类污染物残留水平较低,但重金属含量相对较高,存在一定生态风险;区域内的印刷厂、造纸厂、彩印厂是土壤污染物的主要来源;滇池湖滨蔬菜种植区土壤环境质量尚为清洁,能够保障蔬菜产品品质安全。     

Assessing the health risk of heavy metals in vegetables to the general population in Beijing, China

A systematic survey of As, Cd, Cr, Cu, Ni, Pb and Zn concentrations in vegetables from 416 samples (involving 100 varieties) in Beijing was carried out for assessing the potential health risk to local inhabitants. The results indicated that the metal concentrations in vegetables ranged from < 0.001 to 0.479 g/g fresh weight (fw) (As), < 0.001 to 0.101 g/g fw (Cd), < 0.001 to 1.04 g/g fw (Cr), 0.024 to 8.25 g/g fw (Cu), 0.001 to 1.689 g/g fw (Ni), < 0.001 to 0.655 g/g fw (Pb) and 0.01 to 25.6 g/g fw (Zn), with average concentrations of 0.013, 0.010, 0.023, 0.51, 0.053, 0.046 and 2.55 g/g fw, respectively. The results showed that the concentrations of As, Cr, Cu, Cd, Pb and Ni in vegetables from open-fields were all significantly higher than those grown in greenhouses. In addition, in local-produced vegetables, all HMs except Zn were significantly higher than those in provincial vegetables. The estimated daily intake (EDI) of As, Cd, Cr, Cu, Ni, Pb and Zn from vegetables was 0.080, 0.062, 0.142, 3.14, 0.327, 0.283 and 15.7 g/(kg body weight (bw) d) for adults, respectively. Arsenic was the major risk contributor for inhabitants since the target hazard quotient based on the weighted average concentration (THQw) of arsenic amounted to 44.3% of the total THQ (TTHQ) value according to average vegetable consumption. The TTHQ was lower than 1 for all age groups, indicating that it was still safe for the general population of Beijing to consume vegetables.     

上海市饮用水源地周边环境中的重金属

对上海市饮用水源地周边环境介质(农田土壤、道路灰尘和蔬菜)中重金属的累积特征进行了研究,分析了重金属的空间结构特征及主要污染来源,揭示了周边环境中重金属对水环境的影响,并对重金属的生态风险状况进行了评估.研究表明:①饮用水源地周边各环境介质中重金属已出现不同程度的累积,道路灰尘重金属Cd、Hg、Pb、Cu、Zn、Ni、Cr和As的平均含量分别为0.80、0.23、148.45、127.52、380.57、63.17、250.38和10.37mg·kg-1;农田土壤含量相对较低,分别为0.16、0.33、30.14、30.66、103.79、24.04、65.75和6.31mg·kg-1;蔬菜中8种重金属的平均含量分别为0.010(Cd)、0.016(Hg)、0.36(Pb)、12.80(Cu)、61.69(Zn)、2.04(Ni)、2.41(Cr)和0.0391mg·kg-1;②通过半方差分析和多元分析,推断人类活动的输入是农田土壤重金属积累的最主要原因,而交通污染则是道路灰尘重金属的主要来源;③蔬菜对土壤重金属的富集系数表现为:Zn(0.589)>Cu(0.412)>0.102(Ni)>Cd(0.059)>Cr(0.061)>Hg(0.061)>Pb(0.012))As(0.007),蔬菜中Cd和Zn主要源于根系对土壤重金属的吸收,其它重金属元素可能主要源于气孔对大气污染物的吸收;④周边土壤是水源地沉积物的重要物源,但沉积物与周边环境介质重金属含量不存在显著性相关;⑤重金属生态风险模糊综合评估结果,农田土壤表现为无警-预警,道路灰尘为预警-轻警,蔬菜为预警-轻警,3种环境介质综合评估结果为预警-轻警.     

上海市秋季蔬菜硝酸盐含量及风险摄入评估

对上海市秋季蔬菜中硝酸盐的含量及居民硝酸盐摄入情况做分析和评估,于2009年9～11月从上海市松江、奉贤、金山和浦东4个区的采集了大棚和露地的25个品种439个蔬菜样品,用紫外分光光度法测定蔬菜的硝酸盐含量.结果表明,所有蔬菜样品中,污染程度严重的占41.46%,中、重度污染的占30.53%,轻度的占28.02%.不同种类蔬菜的硝酸盐含量从高到低依次为叶菜类、根茎类、瓜类、豆类、茄果类,同类蔬菜不同品种的硝酸盐含量差别也较大.浦东新区叶类、根茎类蔬菜硝酸盐含量大棚明显高于露地,奉贤区和松江区蔬菜硝酸盐含量均值都为露地高于大棚.上海市居民每日通过蔬菜摄入的硝酸盐为445.22 mg,比WHO/FAO的ADI值高出38.42%,研究结果表明需要加强蔬菜施肥的监督管理.     

滇池流域套作玉米对蔬菜农田地表径流污染流失特征的影响

采用田间小区试验,在自然降雨条件下,对滇池流域蔬菜(豌豆、西葫芦、马铃薯)单作与玉米套作蔬菜两种种植模式下农田地表径流的产生量与径流污染(TN、TP、COD、SS)的浓度进行了分析研究.结果表明:蔬菜单作和玉米套作蔬菜种植模式下地表径流量分别为94.7～128.9m·3hm-2和52.6～76.4m·3hm-2.蔬菜单作种植模式下地表径流中TN、TP、COD和SS浓度分别为10.6～35.8、0.79～3.23、54.6～224.1和35.0～478.3mg·L-1,流失量分别为1.74～2.39、0.18～0.26、7.71～10.59和10.4～21.7kg·hm-2;地表径流TP流失量以马铃薯单作模式最大,其余径流污染流失量以豌豆单作种植模式最大.玉米与蔬菜套作种植模式下地表径流中TN、TP、COD和SS浓度分别为11.7～23.8、0.23～3.54、26.5～222.1和49.7～541.3mg·L-1,流失量分别为0.82～1.22、0.10～0.16、4.17～6.03和8.71～12.6kg·hm-2;地表径流污染流失量均以玉米套作西葫芦种植模式最小.玉米套作蔬菜种植模式显著减少蔬菜农田地表径流量和径流污染流失,对地表径流量、地表径流TN、TP、COD和SS流失量的最大削减率分别为44.5%、53.1%、46.4%、52.1%和42.2%.     

蔬菜中喹诺酮类抗生素污染探查与风险评价:以广州市超市蔬菜为例

基于超声提取-固相萃取(MW-SPE)预处理方法和高效液相色谱-串联质谱(HPLC-MS/MS)分析技术,对广州市超市蔬菜中4种喹诺酮类抗生素(QNs)的污染状况进行探查与健康风险评价.结果表明,4种喹诺酮类化合物的检出率均大于90%,蔬菜(干重,下同)中单个化合物最高含量约150μg/kg,总含量(∑QNs)在10....     

现实版开心农场等你来

农夫、山泉、有点田,这是遥不可及的梦想,还是正在走近的现实？别担心,别着急,盆栽蔬菜、都市菜园可以让你好好过一把现代都市农夫的瘾。     

Predicting As, Cd and Pb uptake by rice and vegetables using field data from China

Plant uptake factor (PUF), single-variable regression of natural log-transformed concentrations in rice grain/vegetables versus natural log-transformed concentrations in soil and multiple-variable regression with soil concentrations and pH, was derived, validated and compared based on the paired crop and soil data collected from studies regarding As, Cd and Pb contaminated croplands in China. Results showed that the median value of PUF did not present deterministic prediction. But after natural logarithm transformation, the PUF followed Gaussian distribution which could be useful in risk assessment. The single-variable regression models were significant for As, Cd and Pb uptake both by rice and vegetables; however, the standard errors of all the regressions were comparatively large. Soil pH as a variable was generally significant but it only contributed positively to model fit for Cd uptake. After model comparison and selection, the upper 95% prediction limits of the multiple regression model for Cd uptake by rice was recommended to calculate screening value of Cd for paddy soil based on the limit for Cd concentration in rice grain.     

接种AM真菌对胡萝卜生长和辛硫磷残留的影响

在温室盆栽条件下研究了接种AM(arbuscular mycorrhiza)真菌对灭菌土壤中胡萝卜生长及其辛硫磷残留的影响.试验设置不施加、低(200 mg.L-1)、中(400 mg.L-1)、高(800 mg.L-1)等4个辛硫磷施用量水平,以及Glomus intraradices BEG 141(141)和Glomus mosseae BEG 167(167)和不接AM真菌的对照(CK)等3个接种处理.播种5个月后收获植株.辛硫磷在收获前14 d以灌根的方式施加.结果表明,尽管菌根侵染率在高辛硫磷施用量时有所降低,但均超过70%.辛硫磷施用量高低对于胡萝卜产量和地上部鲜重没有显著影响;在所有辛硫磷水平下,接种AM真菌均显著增加了胡萝卜产量和地上部鲜重.胡萝卜中辛硫磷残留随农药施用量增加而升高,接种AM真菌显著降低了胡萝卜根和地上部辛硫磷残留.无论在促生效应还是在降低辛硫磷残留方面,141菌剂要优于167菌剂.研究结果显示了AM真菌用于胡萝卜生产和降低农药残留的潜力.