Uptake of 14C-atropine and/or its transformation products from soil by wheat (Triticum aestivum var Kronjet) and their translocation to shoots

Plant uptake of toxins and their translocation to edible plant parts are important processes in the transfer of contaminants into the food chain. Atropine, a highly toxic muscarine receptor antagonist produced by Solanacea species, is found in all plant tissues and can enter the soil and hence be available for uptake by crops. The absorption of atropine and/or its transformation products from soil by wheat (Triticum aestivum var Kronjet) and its distribution to shoots was investigated by growing wheat in soil spiked with unlabeled or ¹⁴C-labeled atropine. Radioactivity attributable to ¹⁴C-atropine and its transformation products was measurable in plants sampled at 15 d after sowing (DAS) and thereafter until the end of experiment. The highest accumulation of ¹⁴C-atropine and/or its transformation products by plants was detected in leaves (between 73 and 90% of the total accumulated) with lower amounts in stems, roots, and seeds (approximately 14%, 9%, and 3%, respectively). ¹⁴C-Atropine and/or its transformation products were detected in soil leachate at 30, 60, and 90 DAS and were strongly adsorbed to soil, with 60% of the applied dose adsorbed at 30 DAS, plateauing at 70% from 60 DAS. Unlabeled atropine was detected in shoots 30 DAS at a concentration of 3.9 ± 0.1 μg kg^?1 (mean ± SD). The observed bioconcentration factor was 2.3 ± 0.04. The results suggest a potential risk of atropine toxicity to consumers.     

Contamination of wild-grown edible mushrooms by heavy metals in a former mercury-mining area

The aim of this study was to evaluate the contamination of six edible wild species of mushrooms (Boletus pulverulentus, Cantharellus cibarius, Lactarius quietus, Macrolepiota procera, Russula xerampelina and Suillus grevillei) by heavy metals (Hg, Cd, Pb, Zn, Cu, Ni, Cr, Co, Mn and Fe). Mushroom samples were collected from sites contaminated by emissions from mining and processing of polymetallic ores in operation during the period 1969–1993 in Rudňany, southeast Slovakia. The four study sites spanned up to a 5-km distance from the emission source. The collected mushroom samples were analyzed using Flame Atomic Absorption Spectrophotometry and/or Flame Atomic Absorption Spectrophotometry with graphite furnace. Mercury, Cd and, in some samples, also Pb present the highest risks in terms of contamination of the food chain following subsequent consumption. The content of two metals in the dry matter (dm) of the mushrooms exceeded the limits set by the European Union (EU; Cd: 0.5 mg/kg dm, Pb: 1.0 mg/kg dm). The highest mean contents of the eight metals recorded for S. grevillei were 52.2, 2.15, 107, 104, 2.27, 2.49, 81.6 and 434 mg/kg dm for Hg, Pb, Zn, Cu, Ni, Cr, Mn and Fe, respectively. The highest content of Cd was recorded in M. procera (3.05 mg/kg dm) and that of Co in L. quietus (0.90 mg/kg dm). The calculated weekly intake for Hg, Pb and Cd shows that regular consumption of mushrooms from the studied area poses risks to human health.     

Measurements of surface contamination of spray equipment with pesticides after various methods of application

Abstract

A traditional method to determine operator dermal exposure is to quantify the amount of pesticide coming into contact with specific body regions and then to integrate the deposition density values with the total body surface. It is known that extremely high deposition values may occur in the hand region; however, the source of contamination is generally assumed to be direct splash or contact with the pesticide container. One of the parameters affecting operator/pilot exposure could be the transfer of pesticide residue, particularly in the case of pesticides with a longer half‐life, from contaminated surfaces of spray equipment by direct contact over extended periods. If the rate of skin absorption of pesticide is readily known, the expected values of daily dose for an operator or pilot may significantly rise due to the extended contact period. This study produced field data on the surface contamination of spray equipment used for ground and aerial applications. If field data on precise work practice (time‐motion) observations are incorporated, it may be possible to estimate the potential exposure of operator/pilot due to hand contact with contaminated surfaces.     

Effects of Soil Amendments at a Heavy Loading Rate Associated with Cover Crops as Green Manures on the Leaching of Nutrients and Heavy Metals from a Calcareous Soil

The potential risk of groundwater contamination by the excessive leaching of N, P and heavy metals from soils amended at heavy loading rates of biosolids, coal ash, N‐viro soil (1:1 mixture of coal ash and biosolids), yard waste compost and co‐compost (3:7 mixture of biosolids to yard wastes), and by soil incorporation of green manures of sunn hemp (Crotalaria juncea) and sorghum sudangrass (Sorghum bicolor × S. bicolor var. sudanense) was studied by collecting and analyzing leachates from pots of Krome very gravelly loam soil subjected to these treatments. The control consisted of Krome soil without any amendment. The loading rate was 205 g pot^? 1 for each amendment (equivalent to 50 t ha^? 1 of the dry weight), and the amounts of the cover crops incorporated into the soil in the pot were those that had been grown in it. A subtropical vegetable crop, okra (Abelmoschus esculentus L.), was grown after the soil amendments or cover crops had been incorporated into the soil. The results showed that the concentration of NO₃‐N in leachate from biosolids was significantly higher than in leachate from other treatments. The levels of heavy metals found in the leachates from all amended soils were so low, as to suggest these amendments may be used without risk of leaching dangerous amounts of these toxic elements. Nevertheless the level of heavy metals in leachate from coal ash amended soil was substantially greater than in leachates from the other treatments. The leguminous cover crop, sunn hemp, returned into the soil, increased the leachate NO₃‐N and inorganic P concentration significantly compared with the non‐legume, sorghum sudangrass. The results suggest that at heavy loading rates of soil amendments, leaching of NO₃ ^? could be a significant concern by application of biosolids. Leaching of inorganic P can be increased significantly by both co‐compost and biosolids, but decreased by coal ash and N‐viro soil by virtue of improved adsorption. The leguminous cover crop, sunn hemp, when incorporated into the soil, can cause the concentration of NO₃‐N to increase by about 7 fold, and that of inorganic P by about 23% over the non‐legume. Regarding the metals, biosolids, N‐viro soil and coal ash significantly increased Ca and Mg concentrations in leachates. Copper concentration in leachate was increased by application of biosolids, while Fe concentration in leachates was increased by biosolids, coal ash and co‐compost. The concentrations of Zn, Mo and Co in leachate were increased by application of coal ash. The concentrations of heavy metals in leachates were very low and unlikely to be harmful, although they were increased significantly by coal ash application.     

单体米黄大理石矿粉对小麦产量及各器官重金属含量的影响

采用盆栽法,研究大理石矿粉对小麦产量及对成熟期小麦根、茎叶、果实中重金属含量的影响。结果表明:添加大理石矿粉会显著影响小麦的生长及产量(P<0.05),添加矿粉的量不大于60g/kg时,小麦的结实小穗数、穗粒数、千粒重和产量随添加量的增加而增加,而含量再继续增大时,对小麦产量的促进作用将减弱;低含量的大理石矿粉能缓解Pb、Cu、Zn对小麦的毒害,而高含量的对小麦的影响各异,小麦各器官中重金属Cd、Cr与添加大理石矿粉含量呈显著正相关;重金属对小麦各器官的影响排序,根:Cd>Cr>Pb>Cu>Zn,茎叶:Cd>Cr>Cu>Pb>Zn,果实:Cd>Cr>Pb>Zn>Cu。在大理石开采区应该采取一定的措施,避免大量的大理石矿粉散入周围的耕地。     

Enhanced 1,2-dichloroethane degradation in heavy metal co-contaminated wastewater undergoing biostimulation and bioaugmentation

Biostimulation, bioaugmentation and dual-bioaugmentation strategies were investigated in this study for efficient bioremediation of water co-contaminated with 1,2-dichloroethane (1,2-DCA) and heavy metals, in a microcosm set-up. 1,2-DCA concentration was periodically measured in the microcosms by gas chromatographic analysis of the headspace samples, while bacterial population and diversity were determined by standard plate count technique and Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR–DGGE) analysis, respectively. Dual-bioaugmentation, proved to be most effective exhibiting 22.43%, 26.54%, 19.58% and 30.49% increase in 1,2-DCA degradation in microcosms co-contaminated with As³⁺, Cd²⁺, Hg²⁺ and Pb²⁺, respectively, followed by bioaugmentation and biostimulation. Dual-bioaugmented microcosms also exhibited the highest increase in the biodegradation rate constant (k₁) resulting in 1.76-, 2-, 1.7- and 2.1-fold increase in As³⁺, Cd²⁺, Hg²⁺ and Pb²⁺ co-contaminated microcosms respectively, compared to the untreated microcosms. Dominant bacterial strains obtained from the co-contaminated microcosms were found to belong to the genera Burkholderia, Pseudomonas, Bacillus, Enterobacter and Bradyrhizobium, previously reported for 1,2-DCA and other chlorinated compounds degradation. PCR–DGGE analysis revealed variation in microbial diversity over time in the different co-contaminated microcosms. Results obtained in this study have significant implications for developing innovative bioremediation strategies for treating water co-contaminated with chlorinated organics and heavy metals.     

Monitoring of heavy metal and organic compound levels along the Eastern Aegean coast with transplanted mussels

Within the framework of the MYTITURK project, heavy metals and organic compounds contaminations were assessed in transplanted mussels in eight different bays from the Eastern Aegean coast. Izmir Bay, Canakkale Strait entrance, Saros and Candarli Bay were defined low pollution extent according to Principal Component Analysis taking into metal accumulation. PAHs (Polycyclic Aromatic Hydrocarbons) levels in the range of 29.4–64.2 ng g⁻¹ (dry weight) indicated that PAH contamination level classified as low along the Aegean coast. Concentrations of Aroclor1254 and 1260 were higher in transplanted mussels from Canakkale Strait Outlet due to industrial activities was originated from Marmara Sea. The organochlorinated pesticides such as heptachlor (<0.4 ng g⁻¹), aldrin (<0.30 ng g⁻¹), dieldrin (<0.75 ng g⁻¹), endrin (<2.3 ng g⁻¹) concentrations were homogeneous however, HCB (Hexachlorobenzene) and lindane concentrations were found undetectable level along the coast. DDE/DDT ratio in the caged mussels form Gulluk and Gokova Bay indicated recent DDT (Dikloro difenil trikloroethan) usage in these areas. The residues of organochlorinated compounds in transplanted mussels confirm the long persistence of DDTs. According to world health authorities, the concentration of heavy metals in mussels for the study area can generally be considered not to be at levels posing a health risk except Zn. The levels of POPs indicated that transplanted mussels have a lack of risk for the human health.     

城市生活垃圾焚烧处理过程中重金属迁移规律研究

通过采集厦门2个垃圾焚烧发电厂进厂垃圾、渗滤液、飞灰、炉渣和烟气样品,分析垃圾组成成分及各组分的重金属含量,结果表明,垃圾中以厨余、橡塑类和纸类为主,共占到垃圾干基的78．08％,重金属含量大小次序为Zn〉Cu〉Pb〉Cr〉Ni〉Cd〉Hg;垃圾渗滤液中除Zn外,其他金属的含量都较低,一厂渗滤液中重金属Ni、Zn迁移量较大,分别达到24．46％和8．52％。二厂渗滤液中重金属的迁移有相同的趋势,但含量相对较高。垃圾焚烧后其重金属主要分布在飞灰和废渣中,烟气中的含量非常少,不同金属的含量均有差别,这与金属的性质有很大关系;通过浸出毒性分析,飞灰中重金属酸溶态含量多,容易浸出,属于危险废物。同时,不同烟气处理工艺产生的飞灰的重金属浸出量有很大差别。     

太湖表层沉积物重金属污染评价与来源分析

对太湖湖区表层沉积物中11种重金属的总量进行调查分析,借助地累积指数法和潜在生态风险指数法分析了重金属的污染程度和生态风险,并利用主成分分析-绝对主成分分数-多元线性回归受体模型对重金属来源进行解析.结果显示太湖沉积物中Cd、Sb含量平均值分别为江苏省土壤背景值的4.29倍和3.18倍,地累积指数表明Cd和Sb为偏中度...