Douay F, Roussel H, Pruvot C, Loriette A, Fourrier H
Laboratoire Sols et Environnement, Institut Supérieur d'Agriculture, 48 boulevard Vauban 59000 Lille, France.
Sci Total Environ. 2008 Aug 15;401(1-3):29-38. doi: 10.1016/j.scitotenv.2008.03.025. Epub 2008 May 16.
Vegetables cultivated in kitchen gardens that are strongly contaminated by heavy metals (Pb, Cd) may represent to consumers a means of exposure to these metals. This exposure is more problematic for those families that include a large quantity of home-grown vegetables in their diet. Researchers have shown that the majority of vegetables produced in kitchen gardens in the vicinity of the Metaleurop Nord smelter (Northern France) do not conform to European regulations. This study was carried out in three of these kitchen gardens. The concentrations of Cd and Pb in the topsoils were up to 24 and 3300 mg kg(-1) respectively. The method consisted of delineating a surface area of about 50 to 100 m(2) for each garden, then removing the contaminated soil and replacing it with a clean one. Seven species of vegetables were cultivated from 2003 to 2005 in the original contaminated soils and the remediated ones. The data showed a clear improvement of the quality of the vegetables cultivated in remediated soils, although 17% of them were still over the European legislative limits for foodstuffs. This suggested that there was a foliar contamination due to contaminated dust fallout coming from the closed smelter site and the adjacent polluted soils. In addition, the measurement of the Cd and Pb concentrations in the dust fallout showed that the substantial rise in metal concentrations in the remediated soil was not only due to atmospheric fallout. These results raise questions about possible technical, economic and sociological problems associated with this kind of remediation.
菜园里种植的蔬菜若受到重金属（铅、镉）的严重污染，可能会成为消费者接触这些金属的途径。对于那些在饮食中大量食用自家种植蔬菜的家庭来说，这种接触带来的问题更为严重。研究人员发现，法国北部梅塔洛尤普·诺德冶炼厂附近菜园产出的大部分蔬菜都不符合欧洲规定。本研究在其中三个菜园开展。这些菜园表层土壤中镉和铅的浓度分别高达24毫克/千克和3300毫克/千克。方法是为每个菜园划定一块约50至100平方米的区域，然后清除受污染土壤，换上干净土壤。2003年至2005年期间，在原来受污染的土壤和经过修复的土壤中种植了七种蔬菜。数据表明，在经过修复的土壤中种植的蔬菜质量有明显改善，不过仍有17%的蔬菜超出了欧洲食品立法限制。这表明，由于来自已关闭的冶炼厂场地和相邻污染土壤的受污染灰尘沉降，存在叶面污染。此外，对灰尘沉降中镉和铅浓度的测量表明，修复后土壤中金属浓度的大幅上升不仅是由于大气沉降。这些结果引发了关于这种修复可能带来的技术、经济和社会问题的疑问。
