Biomarkers allow an integrated risk assessment of heavy metal pollution effects in living organisms. In this study, the biochemical effects of Cd, Cr, Ni, Pb and Zn pollution in agricultural soil and their accumulation in Alium cepa L. (onion) were evaluated with ALA-D enzyme response as a biomarker, along with δ-aminolevulinic acid (ALA) and total chlorophyll contents in leaves of this plant. Soil samples were randomly selected from agricultural areas in two regions, Mitrovica and Obiliqi, which are considered the most industrially polluted regions in Kosovo. Results show that Pb and Zn concentrations in soil samples from Mitrovica (1953-2576 mg kg -1) and Obiliqi regions (138-179 mg kg -1) and their bioaccumulation levels in onion were significantly higher in comparison with the control group. There was an adverse negative correlation between Pb or Zn concentration and ALA-D activity and total chlorophyll content, and a positive correlation with ALA content. This study indicates that ALA-D activity can be used as a very sensitive biomarker for evaluation of heavy metal pollution. The bioaccumulation of heavy metals from soil polluted areas poses a threat for food contamination and public health.

中文翻译：

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通过敏感的生物标志物δ-氨基乙酰丙酸脱水酶（ALA-D）对科索沃污染地区种植的洋葱植物进行重金属毒性风险评估。

生物标志物可以对生物体内重金属污染的影响进行综合风险评估。在这项研究中，以ALA-D酶反应作为生物标志物以及δ-氨基乙酰丙酸对农业土壤中Cd，Cr，Ni，Pb和Zn污染及其在Alium cepa L.（洋葱）中的累积的生化作用进行了评估。 （ALA）和该植物叶片中的总叶绿素含量。从米特罗维察和奥比里奇两个地区的农业地区中随机选择土壤样品，这两个地区被认为是科索沃工业污染最严重的地区。结果表明，米特罗维察（1953-2576 mg kg -1）和奥比里奇地区（138-179 mg kg -1）的土壤样品中铅和锌的浓度以及其在洋葱中的生物富集水平均显着高于对照组。铅或锌的浓度与ALA-D活性和总叶绿素含量之间呈负负相关，与ALA含量呈正相关。这项研究表明，ALA-D活性可用作评估重金属污染的非常敏感的生物标记。来自土壤污染区的重金属的生物蓄积对食品污染和公共健康构成威胁。