Application of Principal Component Analysis in the Assessment of Essential and Toxic Metals in Vegetable and Soil from Polluted and Referent Areas

B. BALABANOVA¹, T. STAFILOV² and K. BAČEVA^2
1 Goce Delčev University, Faculty of Agriculture, 2000 Štip, Macedonia
² Sts. Cyril and Methodius University, Institute of Chemistry, Faculty of Science, 1000 Skopje, Macedonia

Abstract

BALABANOVA, B., T. STAFILOV and K. BAČEVA, 2015. Application of principal component analysis in the assessment of essential and toxic metals in vegetable and soil from polluted and referent areas. Bulg. J. Agric. Sci., 21: 536–544

The aim of the paper is to assess the 21 elements distribution in agricultural soil and vegetables [garlic (Allium sativum), onion (Allium cepa) and parsley (Petroselinum crispum)] widely used as food in areas contaminated with toxic metals due to long-lasting copper mining activities in the Republic of Macedonia. Principal components analysis (PCA) models were computed with different variables: elements contents in vegetables and soil samples collected from contaminated and uncontaminated areas and the bioaccumulation and transferring factors for hazardously metals. Bioaccumulation and mobility of the elements were determined with three soil extraction methods: in 0.1 M HCl; in H₂O and in a mixed buffered solution of diethylenetriaminepentaacetic acid, CaCl₂ and triethanolamine (DTPA-CaCl₂-TEA). Inductively coupled plasma - atomic emission spectrometry (ICP-AES) was applied to determine the contents of the analyzed elements content in the vegetables, soils and soil extracts. The total contents in soil were found above the European standards for As, Cd, Cu and Pb in urban and mines environ, while the vegetables were enriched with Pb and Cd in polluted areas. The PCs plant and soil models (PCA1, PCA2 and PCA3 models) were very useful in determination the relation/correlation of the elements contents in soil (total and extractable contents) and vegetable species. Significant extraction efficiency was obtained for HCl extraction agent (for Ag, Al, Ba, Ca, Cr, K, Li, Mg, Mn, Mo, Na, Ni, P, V and Zn) and for DTPA-CaCl₂-TEA (for Cd, Cu, partially Ni, and Pb). Parsley, onion and garlic showed higher translocation efficiency for As, Cd, Cu and Pb in urban area and mines polluted areas (TF > 1).

Key words: Toxic metals, vegetables, agriculture soil, ICP-AES, PCA
Abbreviations: PCA - Principal Components Analysis; PCA1 - Principal Components Analysis model for soil (elements contents vs. total and extractible contents); PCA2 - Principal Components Analysis model 2 for plants (elements contents vs. vegetable species); PCA3 - Principal Components Analysis model 3 for plants and soil (elements contents vs. vegetable species vs. soil); DTPA - Diethylenetriaminepentaacetic acid; TEA - Triethanolamine; ICP-AES - Inductively coupled plasma with atomic emission spectrometry

See the article as a PDF.