This work is aimed to present the forms of lead in soil taking in the account its' acid and basic conditions. Different forms of heavy metals in soil could have a negative impact on plants and human beings, particularly if they present in higher concentrations than maximum allowed. Various soil conditions cause the different bioavailability of some forms of heavy metals to plants. This paper considers the bioavailability of lead to some plants in acid and basic soil conditions using computer software and comparing results to those obtained by experiment in the laboratory. Obtained results in this work could be used to predict the behavior of heavy metals in different soil conditions, particularly those that are present in very small concentrations, such as lead, cadmium, etc.

A simple and highly sensitive direct spectrophotometric method was developed for the determination of L-ascorbic acid. Potassium cyanide (9.21x10-5 mol dm-3) was used to stabilize ascorbic acid in aqueous medium. Th e molar absorptivity of the proposed method, which does not require an extraction procedure, was 1.38x104 dm3 mol-1 cm-1 at 264 nm. Beer’s law was obeyed in the concentration range of 0.26 – 12.0 μg ascorbic acid cm-3. Th e relative standard deviation was 1.40 % for the determination of 8.0 μg ascorbic acid cm-3 (n = 7).

This works presents results of research in influence of pasteurization parameters to the K-sorbat share in pasteurized dried plumb. Control of the K-sorbat share is important for the effect of preservation on one hand and for its influence on health on the other – or for satisfaction of regulations wich limited this part in the conservation. During the wet pasteurization the plumb is treated with hot solution of K-sorbat with aim of additional protection from spoiling. The K-sorbat part in final product is measured by HPLC method. Achived results enable defining the input parameters of wet pasteurization and establishment of legally determined critical limits.