Transfer of Some Toxic Metals from Soil to Honey Depending on Bee Habitat Conditions

Abstract

The transfer of toxic metals from soil to honey was studied based on two different areas of the Podkarpackie region located in the south-east part of Poland: U-urbanized and E-ecologically pure. The metal content was determined using the ICP-OES method with prior microwave mineralization of the soil, plant (goldenrod, dandelion, rapeseed, tilia and fir), bee bodies and honey samples collected from 10 sampling points (U-5 and E-5). The impact of soil pH on heavy metal mobility was also evaluated. It was found that Podkarpackie soils are less contaminated with heavy metals as compared to other regions of Poland and only in the case of cadmium an enhancement of the natural background level was observed. The migration of heavy metals, especially cadmium, in the soil-plant-bee-honey food chain was accelerated by soil acidity (p<0.05). The influence of human activity (region development) on heavy metals concentrations was not significant (p>0.05). Based on bioaccumulation factors, goldenrod and dandelion plants were confirmed as cadmium accumulators. It was also confirmed that the bodies of bees act as an effective barrier to the migration of heavy metals from the environment to honey, due to this, honey is free from these metals and safe for human consumption.