Concentration Levels of Trace Elements in Carrots, Onions, and Potatoes Cultivated in Asopos Region, Central Greece

Abstract

The objective of the work was to investigate the correlation between the environmental pollution of Asopos river area in Viotia, Greece and the concentration of Ni, Cr, Cd, Pb, Cu, and As in specific crops (carrots, onions, and potatoes) produced in this region. Samples of these crops from Asopos and other Greek areas (control) were collected. For method accuracy, the Certified Reference Material, CRM 281 (trace elements in rye grass) was measured. Simultaneous multi-element graphite furnace atomic absorption spectrometry was used after a microwave acid digestion. The levels of Ni in Asopos food were found up to 9 times higher than control (e.g., Asopos potatoes had an average Ni content of 800 µg/kg compared to 78 µg/kg in control, whereas Asopos carrots had an average Ni content of 474 µg/kg compared to 93 µg/kg in control). Likewise, the levels of Cr were found to be about 2 times higher than control (e.g., Asopos carrots were found to have an average Cr content of 43 µg/kg compared to 20 µg/kg in control). The levels of Cd and Pb had a high variance in the Asopos sourced food. Arsenic was not detected in any sample. Our results indicate that the mean intake of trace elements (Ni, Cr, Pb, Cd, and Cu) by adults through consumption of crops from Asopos, for an average consumption pattern, generally is well below the Allowable Daily Intakes (ADIs). Comparison was also made with data from literature from Greece.

Keywords:

• Asopos river
• ETAAS
• Microwave-assisted digestion
• Thiva
• Trace elements

Acknowledgments

This paper is part of a special issue organized by Dr. Nikolaos Thomaidis and Dr. Antony C. Calokerinos from research presented at the Aegean Analytical Chemistry Days Conference in Lesvos, Greece on 29 September–3 October 2010.

Presented as an oral presentation at 7th Aegean Analytical Chemistry Days, Lesvos, Greece, 29 September − 3 October 2010.

Notes

^a The detection limit for Cr was 10 µg/kg wet wt.

^b The detection limit for Pb was 12 µg/kg wet wt.

^c Range (min–max).

^d P_{(for confidence level 95%)}: 0.004.

^e P_{(for confidence level 95%)}: 0.193.

^f P_{(for confidence level 95%)}: 0.160.

^a The detection limit for Ni was 45 µg/kg wet wt.

^b The detection limit for Cr was 10 µg/kg wet wt.

^c The detection limit for Pb was 12 µg/kg wet wt.

^d Range (min–max).

^e P_{(for confidence level 95%)}: 0.005.

^a The detection limit for Cr was 10 µg/kg wet wt.

^b The detection limit for Pb was 12 µg/kg wet wt.

^c Range (min–max).

^d P_{(for confidence level 95%)}: 0.388.

^a From Data Food Network (DAFNE 2004).

^b Calculated by multiplying the mean levels of an element (left column for each metal), by the mean daily consumption of root vegetables (second column of the table).