镉在成都壤土和几种蔬菜中累积规律的研究

本文报导了镉在不同类型土壤和蔬菜中残留累积规律。研究结果表明,土壤镉残留量随着污水中镉浓度增加而增高,而蔬菜可通过根部吸收土壤中的镉,转移至叶和茎部。土壤中镉残留量与蔬菜中的镉具明显的正相关,与时间呈显著的负相关;蔬菜中镉的累积量依次为小白菜(叶)>萝卜(根)>莴苣(茎)>辣椒(果)>豇豆(豆)。     

公路沿线土壤及蔬菜中多环芳烃的污染

本文介绍采用预分离—高效空心管柱(原称毛细管注)GC法—质谱法,测定公路沿线土壤和蔬菜中20多种PAHs的含量(从二个苯环—七个苯环)。其中,土壤中BaP浓度为79—3581μg/kg干重,蔬菜中为7—720μg/kg干重(下同);测定的约20种PAHs的总体最大含量为36mg/kg(土中)和8mg/kg(菜中)。在实验的基础上,初步讨论了公路交通污染与其它污染的比较;蔬菜污染与其它污染的比较以及可能对人的影响;污染土壤与蔬菜的关系;蔬菜不同部位的PAHs含量,并初步试验了不同清洗方式对蔬菜中PAHs的去除效果。     

中国茶叶中的氟近十年来的研究进展

主要对茶叶中氟的来源,氟含量,氟浸出率以及茶叶降氟措施研究作了详细的综述。大量的研究资料表明,土壤中的氟直接影响到茶叶中氟的含量,茶树吸收氟与土壤的pH值、有机质含量、粘粒含量、成土母质及土壤中的阳离子有关。大气污染影响茶叶氟含量主要是氟通过叶片气孔进入细胞,进而在茶树体内积累。水环境中氟的含量主要受土壤与大气环境的影响。茶叶中的氟含量随着叶片成熟度的增加而增加;茶叶等级越差,氟含量越高;原料粗老的茶类氟含量要比原料较嫩的茶类氟含量高;不同季节、茶树品种对氟吸收也存在差异性;茶树各部位氟累积强度依次为:叶>花蕾>籽>皮>细枝>骨干枝>细根>茎(主轴)>茎(主干)>主根>侧根;茶叶中氟浸出率与冲泡水温、冲泡时间、冲泡次数等有关。在茶叶加工过程中可以通过热水处理,添加化学试剂,改进生产工艺等措施来降低茶叶中的氟含量。此外,尚可以培育含氟量低的茶树品种。     

不同绿地土壤磷水平对麦冬叶养分的影响

对合肥环城公园不同地段绿地土壤及地被植物麦冬叶片的氮磷含量进行了调查分析。结果表明土壤全氮含量平均为1.36 g/kg、全磷为1451.89 mg/kg、有效磷为84.57 mg/kg;麦冬叶的氮磷含量平均值分别为17.25 g/kg和2.83 g/kg,氮磷比为6.33。叶片氮磷比与土壤全磷、有效磷含量呈显著负相关,而与土壤氮含量没有显著相关性。基于叶片氮磷计量关系,调查区植物生长明显受到氮限制。     

桂林市菜地土壤-蔬菜汞污染研究和评价

对桂林市近郊8个不同片区蔬菜产地的118个土壤样品和71个蔬菜样品中汞的含量水平进行了调查和分析。运用单因子污染指数法评价了菜地土壤一蔬菜中汞的污染现状。研究表明，桂林市及近郊菜地土壤和蔬菜已受到不同程度的汞污染，全市各片区菜地土壤汞含量平均值为0．098-0．523mg／kg，以国家土壤环境质量标准二级标准评价，土壤平均污染指数在0．33-1．74范围内，属非污染或轻污染状态，除穿山南片和纸马铺外，其余采样点均有样本超过国家二级标准，其中七星公园东北片的土壤汞超标率较高，达71．4％，污染情况比较均一；虞山桥东南岸土壤汞超标率较低，为33．3％，但土壤汞含量变异较大，说明污染情况变化大。全市各片区老菜的汞含量平均值为0．0625-0．128mg／kg，为国家标准GB2762—1994规定蔬菜汞含量(0．01mg／kg)的6．25—12．8倍，超标率已达100％。实验还发现，蔬菜中的汞含量与土壤中的汞含量具有显著的相关性，且蔬菜汞的大部分分布于地上部可食部分。分析了菜地土壤汞污染的主要原因，可能与使用含汞农药和生活垃圾肥有关。     

广州市蔬菜地土壤重金属污染状况调查及评价

探讨了广州市蔬菜地土壤重金属污染状况,测定了95份土壤样品中铅、镉、铬、砷、汞的含量水平。土壤中铅、镉、铬、砷、汞的含量分别在6.44～153.10mg/kg、0-0.682mg/kg、5.82～101.60mg/kg、0.04～45.36mg/kg、0.01～O.32mg/kg之间。就污染的普遍性而言,铅污染最为普遍,其次是砷污染;就污染的程度而言,镉污染最严重.其次为砷、汞。对比今昔污染变化.广州市土壤污染治理已取得显著成效,但仍需努力。土壤中镉、砷、汞三种元素的变异系数,特别是镉的变异系数较大,这可能预示着点源性污染的存在。     

广州市菜园土主要蔬菜重金属背景含量的研究

研究了广州市几个主要的蔬菜生产基地种植的白菜、芥蓝、芥菜、菜薹、萝卜、大白菜、豆瓣菜、结球甘蓝、芹菜、菜豆、豌豆、结球莴苣、尖叶莴苣、菠菜、番茄等15种蔬菜中Pb、Hg、Cd、Cr和As等5种重金属的背景质量分数。其背景质量分数为：Pb 0．002～0．148mg/kg；Hg ND-0．006mg/kg；Cd 0．001～0．034mg/kg；Cr 0．002～0．150mg/kg；As 0.001～0．070mg／kg。由于不同种类蔬菜的吸收特性和遗传特性有所不同，其重金属背景质量分数也有很大差异。蔬菜中元素水平还与土壤条件等因素有关。     

叶菜类蔬菜硝酸盐含量及其与土壤肥力因素的关系

对长沙市蔬菜生产基地春夏季节3种叶菜类蔬菜硝酸盐含量进行测定并与对应的菜园土壤8个肥力因素进行相关分析。结果表明,叶菜类蔬菜中,以小白菜硝酸盐含量最高,平均含量为3336±1359mg/kg,污染最严重;所调查的14个样本中超过四级标准达到严重污染水平的占64%以上。叶菜类蔬菜硝酸盐含量与土壤硝酸盐含量呈正相关,其中小白菜和苋菜相应的相关系数和通径分析系数均达5%以上显著水平。土壤硝酸盐含量是影响叶菜类蔬菜硝酸盐含量的主要土壤肥力因素。     

珠江三角洲典型地区蔬菜重金属污染现状研究--以中山市和东莞市为例

以珠江三角洲典型地区中山市与东莞市为研究对象，通过对其大型蔬菜生产基地中10种蔬菜76个样品中重金属元素铬、铅、镉和汞的含量进行分析，初步摸清了珠江三角洲典型地区中山市与东莞市蔬菜中的重金属污染状况，并在不同城市不同蔬菜品种之间的污染程度进行了比较。结果表明，蔬菜中铬、铅、镉、汞的平均含量分别为0．1719、0．0962、0．0257和0.0014mg/kg，其中铬、铅、镉含量超出了国家卫生标准的允许量的蔬菜样品分别有1．3％、13，2％与13．2％；4种重金属在10种蔬菜中的平均残留量由大到小依次为：铬→铅→镉→汞；铅、镉是珠江三角洲典型地区中山市与东莞市蔬菜中的主要污染元素。     

四川凉山州9种野生蘑菇的重金属含量

报道了采集于四川凉山州9种野生蘑菇及相关土壤的重金属Cd、Pb、Zn、Hg和As的含量.结果表明,供试土壤均未检出Hg,3个采集地除会理林家山土壤样品有Cd的检出,另外两个样地土壤未检出Cd.土壤中Pb、Zn和As在干土中的含量分别为52.806 4~274.731 0 mg/kg、18.747 5~164.585 8 mg/kg和3.970 9~10.749 9 mg/kg.野生蘑菇对Cd和Hg具有很强的积累能力,在土壤中没有Cd和Hg检出的情况下,蘑菇中均测出了Cd和Hg,Cd含量高达28.383 6 mg/kg出现在梭孢环柄菇(Lepita ventriosospora),Hg含量最高为0.860 7 mg/kg出现在大白菇(Russula deli-ca).在土壤受Pb污染的情况下,大白菇子实体积累Pb的能力最强,含量为115.929 0 mg/kg.本次蘑菇样品Zn的含量不高.蘑菇对As的积累与土壤中As含量高低有关,最高含量为喇叭陀螺菌(Gomphus floccosus),为4.003 5 mg/kg.表明蘑菇对重金属的积累具有种特异性,与环境土壤重金属含量有关.基于蘑菇对重金属的强积累能力,可考虑作为净化重金属污染环境的特种生物.图1表2参11     

氢氧化铝废渣处理含氟废水的研究

在一定条件下氢氧化铝废渣活化处理,用于处理５０ｍｇ／Ｌ的含氟废水,投加量为２‰,ｐＨ值为６￣１１,去氟率达９６％。吸附平衡浓度与吸附量关系符合Ｌａｎｇｍｕｉｒ等温式,求出２０．０℃、２５．０℃、３０．０℃时的饱和吸附量和吸附系数。其吸附速度符合鲛岛吸附动力学方程式。     

辽河流域高氟地区氟对人体健康的影响

研究了辽河流域高氟地区土壤、作物、饮用水中氟含量,并应用目前美国环保局推荐的健康风险评价模型对辽河流域高氟地区饮用水中氟所引起的健康风险进行初步评价。研究表明：研究区饮用水中氟质量浓度为0．70—4．51mg·L^-1;白菜根土中氟质量分数为182—484mg·kg^-1,萝卜根土质量分数为182～352mg·kg^-1,玉米根土中氟质量分数为209～1254mg·kg^-1;白菜可食部分氟质量分数为0．51～2．96mg·kg^-1,萝卜可食部分氟质量分数为0．34～0．50mg·kg^-1,玉米果实部分氟质量分数为0．88～1．04mg·kg^-1。通过饮用水、食物途径所致健康风险中,食人途径、饮用水途径非致癌物年健康风险分别为1．920×10^-9·a^-1,1．960×10^-8·a^-1,均低于国际辐射防护委员会（ICRP）推荐的通过饮水途径最大可接受风险水平（5×10^-5·a^-1）。     

粉煤灰复合吸附剂的研制及其在工业废水除氟中的应用

粉煤灰复合吸附剂是一种新型得除氟剂，具有良好的吸附性能，在一定条件下，可用于处理高含氟量的工业废水，粉煤灰复合吸附剂处理50mg/L左右的含F^－废水时，当投加量为0．6％－0．8％时，去除率可达90％以上，从而达到排放标准，粉煤灰复合吸附剂所需原料易得，除氟后可将原料固化制成建筑用砖，合理利用。     

Fluorine in the UK environment

Relatively low concentrations of fluorine in drinking water ( 1 mg F/l) have been shown to significantly reduce the degree of dental caries in children and fluorine would also appear to have a beneficial effect on bone formation in both humans and farm animals. However, it is apparent that elevated levels of fluorine in the diet have sometimes resulted in problems of increased dental caries and of the development of bone deformities. Much of the fluorine in rocks and soils occurs in apatite and hydroxysilicate minerals, fluorite being the only relatively common rock forming mineral containing fluorine as an essential constituent.Little systematic data are available on fluorine concentrations in soils, plants and natural waters in the UK. General background soil concentrations lie in the range 200 – 400 mg F/kg. For waters the average fluorine content is low, <0.1 mg F/l.In the British Isles there are several areas where there are enhanced levels of fluorine. In the northern Pennines, Derbyshire, northeast Wales and Cornwall, fluorite occurs as a significant component of mineralisation and much fluorine has been added to the environment from mining waste dumps. Soils in northeast Wales contain up to 3,650 mg F/kg and in the northern Pennines up to 20,000 mg F/kg. Waters contain up to 2.3 mg F/l. In southwest England, the granites are generally fluorine-rich with the fluorite granites of the St Austell pluton containing as much as 1 percent fluorine. These rocks are frequently kaolinised and intensively worked as a source of china clay. Soils in the vicinity of the waste tips contain up to 3,300 mg F/kg and grasses up to 2,950 mg F/kg. Surface waters in the St Austell area contain up to 1.25 mg F/l.Atmospheric fluorine pollution around brickworks in the Peterborough and Bedford areas has resulted in fluorosis in farm animals. Other sources of atmospheric fluorine pollution are aluminium smelters, steelworks and fossil fuel burning.     

Arsenic contamination: a potential hazard to the affected areas of West Bengal, India

Arsenic contamination in groundwater is becoming more and more a worldwide problem. Nearing 50 million of people are at health risk from arsenic contamination at Ganga–Meghna–Bramhaputra basin. The experimental results of the five blocks under Malda district of West Bengal, India, showed that the arsenic concentration in groundwater (0.41–1.01 mg/l) was higher than the permissible limit for drinking water (0.01 mg/l) (WHO) and FAO (Food and Agriculture Organization) permissible limit for irrigation water (0.10 mg/l). The soil arsenic level (13.12 mg/kg) crossed the global average (10.0 mg/kg), but within the maximum acceptable limit for agricultural soil (20.0 mg/kg) recommended by the European Union. The total arsenic concentration on food crops varied from 0.000 to 1.464 mg/kg of dry weight. The highest mean arsenic concentration was found in potato (0.456 mg/kg), followed by rice grain (0.429 mg/kg). The total mean arsenic content (milligrams per kg dry weight) in cereals ranged from 0.121 to 0.429 mg/kg, in pulses and oilseeds ranged from 0.076 to 0.168 mg/kg, in tuber crops ranged from 0.243 to 0.456 mg/kg, in spices ranged from 0.031 to 0.175 mg/kg, in fruits ranged from 0.021 to 0.145 mg/kg and in vegetables ranged from 0.032 to 0.411 mg/kg, respectively. Hence, arsenic accumulation in cereals, pulses, oilseed, vegetables, spices, cole crop and fruits crop might not be safe in future without any sustainable mitigation strategies to avert the potential arsenic toxicity on the human health in the contaminated areas.     

玻璃厂氟污染对周围生态环境的影响

不同树种对氟化物的吸收能力有差异.吸收能力和抵抗能力之间并无明显的相关注,因此在氟污染源附近进行环境绿化时,必须选择吸氟和抗氟能力都较强的园林树种.氟污染具有方向性, 可以通过测定不同部位的叶片含氟量来确定污染源的方位.水洗后的叶片含氟量明显下降,说明玻璃厂排放的含氟烟气中,含氟粉尘占有重要地位.对防治玻璃厂的氟污染危害提出了合理的建议.     

大气氟污染的树木监测与评价

本文介绍了采用植物监测与化学静态监测相结合方法,对上海某厂周围大气氟浓度和树叶含氟量进行测定,得出两者相关关系,确定悬铃木生长初期树叶含氟量划分大气氟污染等级指标,并运用生物学办法对影响区进行评价和浓度分区.     

Investigation and risk assessment modeling of As and other heavy metals contamination around five abandoned metal mines in Korea

Tailings, agricultural soils, vegetables and groundwater samples were collected from abandoned metal mines (Duckum, Dongil, Dongjung, Myoungbong and Songchun mines) in Korea. Total concentrations of arsenic (As) and heavy metals (Cd, Cu, Pb and Zn) were analyzed to investigate the contamination level. Several digestion methods (Toxicity characteristics leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), 0.1 N/1 N HCl) and sequential extraction analysis for mine tailings were conducted to examine the potential leachability of As and heavy metals from the tailings. The order of urgent remediation for the studied mines based on the risk assessment and remedial goals was suggested. The Songchun mine tailings were most severely contaminated by As and heavy metals. Total concentrations of As and Pb in the tailings were 38,600–58,700 mg/kg (av. 47,400 mg/kg) and 11,800–16,800 mg/kg (av. 14,600 mg/kg), respectively. Agricultural soils having high As concentrations were found at the all mines. Average concentrations of Cd in the vegetables exceeded the normal value at all mines areas, while As only at the Dongjung, Myoungbong, and Songchun mine area. One groundwater sample each from the Dongil and Myoungbong mines, and 4 groundwater samples from the Songchun mine had values above 10 μg/L of As concentration. The TCLP method revealed that only Pb in the Songchun tailings, 6.49 mg/L, exceeded the regulatory level (5 mg/L). Employing the 1-N HCl digestion method, the concentration of As in the Songchun mine tailings, 4,250 mg/kg, was up to 3,000 times higher than its Korean countermeasure standard. Results from the sequential extraction of As in the tailings showed that the easily releasable fraction in the Myoungbong and Songchun mine tailings was more than 30% and the residual fraction was less than 40%. Based on results showing the exposure health risk employing the hazard quotient and cancer risk of As, Cd and Zn, the Dongil mine needs the most urgent remedial action. The concentration reduction factor (CRF) of As in both soil and groundwater follows the order: Songchun>Dongjung>Dongil>Myoungbong>Duckum mine.     

Mercury contamination and health risk to crops around the zinc smelting plant in Huludao City,northeastern China

The Huludao zinc plant in Liaoning province, northeast China was the largest in Asia, and its smelting activities had seriously contaminated soil, water and atmosphere in the surrounding area. For the first time, we investigated the total mercury (THg) content in maize, soybean, broomcorn, 22 vegetables, and the soil around their roots from eight sampling plots near the Huludao zinc plant. THg contents of the seeds of maize, soybean, and broomcorn are 0.008, 0.006, and 0.057 mg kg⁻¹, respectively, with the broomcorn being the highest, exceeding the maximum level of contaminant in food (GB2762-2005) by 4.7 times. The edible parts of vegetables are also contaminated with a range of mercury contents of 0.001–0.147 mg kg⁻¹ (dry weight). THg contents in plant tissue decrease in the order of leaves > root > stalk > grain. Using correlation analysis, we show that mercury in the roots of these plants is mainly derived from soil, and the uptake of gaseous mercury is the predominant path by which the mercury accumulated in the foliage. The average and maximum mercury daily intake (DI) of adult around the Huludao zinc plant via consuming vegetables are 0.015 and 0.051 μg/kg/d, respectively, and those of children are 0.02 and 0.07 μg/kg/d, respectively. The average and maximum weekly intakes of total mercury for adult are 2.1 and 7.1%, respectively, of the provisional tolerable weekly intake (PTWI), and 2.8 and 9.7%, respectively, of the PTWI for children.     

安徽省土壤中氟分布的研究

安徽省２２９ 个土壤剖面土壤总氟和土壤水溶性氟含量测定数据表明,５ 个地理分区之间土壤总氟差异不大,Ａ 层和Ｃ层均值分别为５２２ ｍ ｇ／ｋｇ 和６０４ ｍ ｇ／ｋｇ;而土壤水溶性氟在不同地区之间的差异显著,其分布规律是自北向南降低：淮北平原＞ 江淮丘陵＞ 沿江平原＞ 皖南山区＞ 大别山区。土壤总氟与土壤水溶性氟无相关性。