The Effect of Immobilizing Agents on Zn and Cu Availability for Plants in Relation to Their Potential Health Risks

Abstract

Soil contamination with heavy metals is one of the most important threats to the environment because they are easily incorporated into the food chain, threatening the health of plants, animals, and humans. In this study, the effectiveness of the introduced substances (compost and fly ash) was assessed in terms of its influence on the content of Cu and Zn in the soil, potential accumulation of these metals in the cultivated plants (camelina and oat), and thus in food products prepared from these plants. Therefore, the following indicators were used: bioconcentration factors calculated for the total amount (BCFT) and bioavailable amount of metals (BCFB) as well as gender-estimated daily intake (EDI) and health risk index (HRI). Regardless of gender, the EDI values ranged from 0.31 µg·kg−1 to 0.49 µg·kg−1 for Cu and from 0.9 µg·kg−1 to 1.8 µg·kg−1 for Zn in oat. For camelina, the calculated values were as follows: 4.1–8.5 µg·kg−1 for Cu and 7.1–12.1 µg·kg−1 for Zn. The HRI values were very low (in general 0.03–0.2), indicating no health risk connected with potential consumption of oat or camelina food products. The amounts of Cu and Zn in the crops grown on the soil amended with compost or fly ash were significantly lower (by 21–37% for oat and 14–34% for camelina) compared to the content of these metals in the control plants. Moreover, the levels of bioavailable metals decreased in soil as a result of the applied immobilizing agents. The study showed that the immobilization efficiency of compost and fly ash was comparable, and therefore the choice of either of these substances for the chemical remediation of soil contaminated with heavy metals is justified.

Importance of Compost, Bentonite, and Calcium Oxide in Reducing Trace Element Content in Maize on Agricultural Soil Contaminated with Diesel Oil

“…Compost also contributed to the greatest reduction in Pb content in soil pore water (<5 mg dm −3 ) compared to the control series (>80 mg dm −3 ). Jakubus and Bakinowska [57] also demonstrated reduced Cu and Zn contents in plants on compostamended soils (by 21-37% for oats and by 14-34% for camelina). The potential of compost in the remediation of contaminated soils has also been confirmed by Awasthi et al [84].…”

“…These changes, in turn, affect the trace element's mobility and bioavailability [56]. The amount of trace elements taken up by plants is limited, as they either form insoluble complexes under alkaline conditions or are bound by organic matter, which effectively prevents their bioaccumulation in the food chain [57].…”

Health Risk of Heavy Metals Related to Consumption of Vegetables in Areas of Industrial Impact in the Republic of Kazakhstan—Case Study for Oskemen

“…Such a potential risk should be assessed in several areas, taking into account the effectiveness of metal bioconcentration in organs and tissues of consumed vegetables and the daily intake of metals through consumptions of various plant products. Based on the amount of metals in the soil and in plants the transfer of heavy metals from soil to plants should be assessed, with bioconcentration factors (BCF) being useful indices in this respect [10,11]. Furthermore, the probable human risk associated with heavy metals should also be evaluated.…”

“…Gupta et al [4], Nag et al [6] and Kumar et al [12] listed such indices including the target, hazard quotient, daily dietary intake of metals, hazard index, daily intake of metals and health risk index. A literature review shows that the most popular indices are daily intake of metals (DIM) and health risk index (HRI) [9,11,[13][14][15][16]. Daily intake of metals can help assess the relative phyto-availability of metals and is proportional to metal concentrations in the edible parts of vegetables as well as the consumed amounts of those vegetables.…”

Special Issue on “Heavy Metal Toxicity: Environmental and Human Health Risk Assessment”

“…In the study of Jakubus et al [6], the effectiveness of the introduced substances (compost and fly ash) was assessed in terms of their influence on the content of Cu and Zn in the soil as well as their potential accumulation in the cultivated camelina and oat, and thus in food products prepared from these plants.…”