Content of Heavy Metals as a Criterium of the Quality of Strawberry Fruit and Soil Properties

The environmental study, carried out in the Lublin region, was aimed at assessment of strawberry fruit quality based on the contents of heavy metals (Pb, Cd, Ni, Zn, Cu, As, Hg) and finding correlation between these heavy metals and some properties of soil and plant. Heavy metals in soil and fruits were determined with ASA method, other analyses according to research procedures of the laboratory of the Regional Agrochemical Station in Lublin. Region of cultivation has no significant effect on the contents of heavy metals in strawberry fruit. Some soil properties have significant effect on occurrence of mainly zinc and mercury and, to a slightest degree, also cadmium and copper in the plant. In the fruits, contents of copper and zinc and, to a slightest degree, also cadmium, nickel, mercury, and lead were dependent on occurrence of other elements in this part of the plant. The average contents of heavy metals in strawberry fruit grown in the Lublin region (0.023 mg Pb, 0.020 mg Cd, 0.091 mg Ni, 1.228 mg Zn, 0.358 mg Cu, 0.0015 mg As, 0.00011 mg Hg kg of fresh matter) indicates that it did not exceed upper threshold of products of this type. Strawberry fruits are in our country a common element of human diet due to great taste value, the content of easily available sugars, mineral salts and vitamins. These plants can be cultivated on less fertile soils, often acidic; therefore in the conditions promoting the uptake of higher amount of heavy metals. Some of them, particularly lead, cadmium, arsenic, and mercury can be a cause of many serious illnesses. Because of that the change of the content of these elements, in particular in the usable parts of plants (grain, seed, fruit, bulb, etc.) [1-3, 6-10] should be carefully monitored. The content of the above metals in Polish soils is, for the most part, very low and natural according to the classification of the Institute of Soil Science and Plant Cultivation IUNG [4]; therefore, potentially it does not create the conditions for the increase of their uptake by the plants. P O L I S H J O U R N A L O F S O I L S C I E N C E VOL. XXXIX/2 2006 PL ISSN 0079-2985