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1.
以重庆市江津区为研究区,采集2019年生产的63份大米籽粒和64份玉米籽粒,用电感耦合等离子质谱仪(ICP–MS)和原子荧光光谱仪(AFS)测定大米和玉米籽粒中砷(As)、钡(Ba)、镉(Cd)、铜(Cu)、铁(Fe)、锰(Mn)、钼(Mo)、镍(Ni)和锌(Zn)的质量分数,并利用环境健康风险模型评价江津区大米和玉米中重金属的健康风险。结果表明:江津区大米和玉米籽粒中As最大质量分数分别为176.0、162.8 μg/kg,低于国家食品卫生As标准(<200 μg/kg);江津区3份大米和6份玉米样品中Cd质量分数超过国家食品卫生Cd标准(大米Cd质量分数<200 μg/kg、玉米Cd质量分数<100 μg/kg);大米籽粒中As和Mo质量分数均值显著高于玉米籽粒的(P<0.05),Cd质量分数均值略高于玉米籽粒的;大米籽粒中As、Cu、Mn和Zn的单因子污染指数均小于1,属于清洁水平,3份大米籽粒样品中Cd属于轻度污染;大米和玉米籽粒重金属综合污染指数分别为1.09和1.57,属于轻度污染,江津区玉米籽粒中重金属污染程度大于大米籽粒;大米籽粒中重金属As和Cd的致癌风险分别占健康总风险的82.7%和16.8%,表明江津区大米籽粒中As含量虽低于国家食品卫生标准安全值,但其健康风险较高,其次为Cd。可见,重庆地区需重点监控农作物中As和Cd的健康风险。  相似文献   
2.
This study identified the role of milling and parboiling on arsenic (As) content and its species in large numbers of rice samples. Total As contents were 108 ± 33 μg/kg in polished rice grains (PR), 159 ± 46 μg/kg in unpolished rice grains (UR), 145 ± 42 μg/kg in parboiled polished rice grains (PPR) and 145 ± 44 μg/kg in parboiled unpolished rice grains (PUR). The percentages of inorganic As (iAs) were 66% ± 8% in PR and from 72% to 77% in other grain categories. The polishing process reduced the As content in the rice grains, removing outer part of the UR with high amount of As, whereas the parboiling technique transferred the semimetal content within the grain. Total As and iAs contents were not significantly different in UR, PPR and PUR, homogenizing its distribution inside the grains. The results allowed to understand how different operations affect As fate and its chemical forms in grains.  相似文献   
3.
Many rice-growing areas are affected by high concentrations of arsenic(As). Rice varieties that prevent As uptake and/or accumulation can mitigate As threats to human health. Genomic selection is known to facilitate rapid selection of superior genotypes for complex traits. We explored the predictive ability(PA) of genomic prediction with single-environment models, accounting or not for trait-specific markers, multi-environment models, and multi-trait and multi-environment models, using the genotypic(1600 K SNPs) and phenotypic(grain As content, grain yield and days to flowering) data of the Bengal and Assam Aus Panel. Under the base-line single-environment model, PA of up to 0.707 and 0.654 was obtained for grain yield and grain As content, respectively; the three prediction methods(Bayesian Lasso, genomic best linear unbiased prediction and reproducing kernel Hilbert spaces) were considered to perform similarly, and marker selection based on linkage disequilibrium allowed to reduce the number of SNP to 17 K, without negative effect on PA of genomic predictions. Single-environment models giving distinct weight to trait-specific markers in the genomic relationship matrix outperformed the base-line models up to 32%. Multi-environment models, accounting for genotype × environment interactions, and multi-trait and multi-environment models outperformed the base-line models by up to 47% and 61%, respectively. Among the multi-trait and multi-environment models, the Bayesian multi-output regressor stacking function obtained the highest predictive ability(0.831 for grain As) with much higher efficiency for computing time. These findings pave the way for breeding for As-tolerance in the progenies of biparental crosses involving members of the Bengal and Assam Aus Panel. Genomic prediction can also be applied to breeding for other complex traits under multiple environments.  相似文献   
4.
利用HPLC-ICP-MS方法测定中华绒螯蟹不同形态砷的残留量   总被引:1,自引:1,他引:0  
殷玉婷  汪倩  陈曦  桂源  宋超 《中国农学通报》2021,37(32):148-156
采用高效液相色谱串联电感耦合等离子体质谱仪(HPLC-ICP-MS)测定中华绒螯蟹可食部位6种砷形态的残留量。经过前处理、提取和脱脂后,通过色谱柱、流动相、pH和流速等参数调节,筛选得到最优化的分离和检测条件。结果表明,6种砷形态的混合标准溶液在质量浓度0~50 μg/L范围时,均呈现良好的线性关系,其R2达到0.999,检测限为0.0060~0.0912 μg/kg,定量限为0.020~0.304 μg/kg。在样品中添加0.5、5、50 μg/L浓度水平,回收率良好,范围是70%~120%,相对标准偏差(RSD)均<5%,方法精密度与重复性均良好。本方法为中华绒螯蟹可食部位砷形态残留量建立了有效检测方法,为水产品砷残留快速检测提供技术支撑。  相似文献   
5.
Rice (Oryza sativa L.), a staple crop for over 50% of the world's population, is also a source of dietary arsenic (As) because of it's efficiencyat accumulating As. Lead–arsenate pesticide was used in agriculture, these soils potentially may be used for rice production. The objective of this study was to determine the effects of compost on total and inorganic As concentrations in rice grown on lead–arsenate contaminated soils. Three lead–arsenatesoils were amended with 10% by weight of compost and planted with rice under flooded and non-flooded conditions. Rice grain yieldwas higher with compost but not flooding. Flooding significantly increased total and inorganic As concentrations. In most cases, rice inorganic Asconcentrations were higher than the limit set by Chinaat 0.2 mg kg?1. Compost at therate used did not reduce rice grain As to safe levels.Lead–arsenate contaminated soils are not recommended for rice production.  相似文献   
6.
Biomonitoring of the local population and environmental monitoring in eastern Croatia have revealed abnormalities in metal and metalloid distribution that could be related to war activities during the 1990s. The goal of this study was to determine whether there are differences in the concentrations of metals and metalloids by comparing locations of high and low-intensity combat activity; we also evaluated a possible connection between metal contamination in soil and in humans. We sampled 14 locations and measured the concentrations of 20 war related metals and metalloids (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Ni, Pb, Sb, Si, Sr, U, V and Zn). The results of principal components analysis showed two main clusters: locations Dopsin and Dalj (both characterized by high-intensity combat activity), where the concentrations of most elements (except Hg) were increased. Although the concentrations of metals and metalloids in cabbage samples collected in eastern Croatia did not exceed the maximum allowed values, the results of our study confirmed existance of environmental ‘hotspot’ with higher concentrations of war metals and metalloids. Our findings indicate that there is a possible common source and mechanism of transferring metals from the environment to the population.  相似文献   
7.
施硒对水稻外观品质及籽粒硒、镉和砷含量的影响   总被引:2,自引:0,他引:2  
喷施叶面硒肥是提高水稻籽粒硒含量的有效措施。通过对杂交水稻隆两优华占在孕穗期施用不同浓度的硒叶面肥,研究了施硒对水稻外观品质及籽粒硒、镉和砷含量的影响。结果表明:①施硒能显著提高水稻的整精米率,降低垩白度,当施用量为23 g/hm~2复合硒叶面肥+20 g/hm~2亚硒酸钠时,整精米率达到最高值65.67%,垩白度达到最低值0.65%;②增施硒肥能增加水稻精米和糙米的硒含量,当施用量为23 g/hm~2硒叶面肥+30 g/hm~2亚硒酸钠时,水稻精米和糙米硒含量分别达到最大值为0.784 3 mg/kg和0.816 7 mg/kg,糙米积累硒的能力高于精米;③增施硒肥对水稻精米和糙米中镉和砷含量均没有显著影响,表明籽粒对硒与镉和砷的吸收没有协同作用。同一处理下糙米镉含量均高于精米镉含量,但差异不显著,糙米对重金属砷的累积效果均显著高于精米。  相似文献   
8.
近年来,重金属污染耕地安全利用技术研究取得了突破进展,然而将这些关键技术与蔬菜传统高度集约化种植模式进行耦合的研究还比较少,大规模推广应用鲜见报道。因此,本文在查阅最新发表文献的基础上,梳理了我国土壤-蔬菜作物系统重金属污染状况,归纳了蔬菜作物重金属吸收积累特征,并总结了重金属污染蔬菜地安全生产综合农艺调控技术研究进展。当前,我国蔬菜地土壤重金属污染以中轻度为主,且区域分异明显。蔬菜作物重金属超标现象在全国各地时有发生,给蔬菜产业发展和人类健康带来了极大的危害。蔬菜作物对重金属的积累能力因种类、品种、部位而异,受基因型、土壤理化性质和外界环境条件的制约,因此调整种植布局、选用重金属低积累品种、合理轮间套作、施用土壤改良剂和钝化剂、优化水肥管理技术等农艺调控措施是目前中轻度重金属污染蔬菜地安全利用的重要技术途径。未来在进一步深入研究土壤-蔬菜系统重金属迁移转化规律的基础上,宜加强土壤-蔬菜地系统安全生产技术标准、传统种植模式与综合农艺调控措施耦合技术、长期定位试验及风险评价等方面的研究,以实现重金属中轻度污染蔬菜地的安全利用和农产品的安全生产。  相似文献   
9.
改性磁性荔枝皮对水及果汁中砷的吸附效果及动力学分析   总被引:2,自引:2,他引:0  
为探索安全高效实用的果汁类食品砷吸附材料,以天然植物副产物荔枝皮为材料,通过共沉法制备砷吸附材料磁性荔枝皮(magnetic litchi peel,MLP),采用电感耦合等离子体质谱法测定砷含量,以砷清除率为判断指标,研究了MLP对三价砷和五价砷吸附效果及机理。结果表明:改性MLP表面含有粉末状的Fe3O4,与未改性荔枝皮相比部分官能团增加,表面粗糙、更加凹凸不平,结构疏松,微孔数量增加,有利于吸附作用的进行,在砷浓度为0.20 mg/L水溶液中三价砷和五价砷吸附率为88%和90%,对苹果汁中的三价砷和五价砷吸附率为83%和93%;MLP对三价砷和五价砷溶液吸附等温线符合Langmuir等温线模型,拟合决定系数R2均大于0.99,为单分子层吸附,在298 K条件下饱和吸附量三价砷为0.181 mg/g,五价砷为0.225 mg/g;MLP对砷溶液吸附动力学可以通过准二级吸附动力学模型描述,R2均高于0.99;MLP对三价砷和五价砷的吸附过程中吉布斯自由能小于0,吸附反应是自发进行的,焓变小于0,MLP对两种价态砷的吸附都是放热反应。研究结果可为改性荔枝皮在果汁类食品中砷脱除方法和工艺的应用提供理论与数据参考。  相似文献   
10.
为研究化学活化剂三聚磷酸钠和柠檬酸配合施用对蜈蚣草萃取砷效率的影响,通过模拟实验,在含砷57.7 mg·kg-1的水稻土中,探究了单一活化剂(三聚磷酸钠0.75 g·kg-1土,柠檬酸0.75 g·kg-1土)和三聚磷酸钠与柠檬酸配合施用(三聚磷酸钠:柠檬酸=0.375 g·kg-1土:0.375 g·kg-1土)对土壤有效态砷含量变化的影响;采用盆栽实验,探究了三聚磷酸钠和柠檬酸配合施用(三聚磷酸钠:柠檬酸=0.187 5 g·kg-1土:0.187 5 g·kg-1土)对蜈蚣草地上部萃取土壤砷的影响。模拟实验结果表明,与单一活化剂相比,三聚磷酸钠和柠檬酸配合施用对土壤砷的活化效果更显著。盆栽实验结果表明:与对照组相比,三聚磷酸钠和柠檬酸配合施用可使蜈蚣草羽叶干质量提高21.8%以上,砷萃取总量提高40.4%以上;根际土总砷含量下降,土壤脲酶和脱氢酶活性显著增加。研究表明在砷污染土壤施加三聚磷酸钠和柠檬酸,由于其提高了蜈蚣草植物干质量和土壤有效态砷含量,羽叶萃取砷效率明显提高。  相似文献   
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