PubMed · 243270
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1977. [In our school].. https://pubmed.ncbi.nlm.nih.gov/243270/
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The aim of the study was to analyse a relationship between the meteorological conditions and the pollen counts of selected allergenic taxa (Betula spp., Populus spp.) in the air of Szczecin city (north western Poland) in 2001. Apart from the individual rhythm of plant pollination, weather conditions are considered the most important factors determining the dispersion and content of pollen in the air. The meteorological parameters analysed were the minimum, maximum and average values of air temperature, relative humidity, solar radiation and wind speed. The beginning and end of a season were established by the 98 % method. The concentration of birch pollen in the air in 2001 was very high, the pollen season started in the third decade of April and lasted till the 10 May. The highest airborne concentration of 3,712 grains in 1 m(3) per 24 h was noted at the beginning of May on a sunny day with strong wind, and air temperature above 20 degrees C. The concentration of poplar pollen in 2001 was low. The pollen season started from the beginning of April and lasted till the beginning of May. The maximum concentration of airborne poplar pollen of 222 grains in 1 m(3) per 24 h was observed in the third decade of April and was preceded by several days with low temperature (1- 2 degrees C), rain, snowfalls and strong wind. A positive and statistically significant correlation was found between the air temperature and the birch pollen concentration, while a similar but negative correlation was found for poplar pollen.
The sorption of polycyclic aromatic hydrocarbons in aquatic sediments from Zegrzyńskie Lake was examined. Batch experiment was performed in order to determine sorption efficiency in different kinds of sediments from Zegrzyńskie Lake. Five polycyclic aromatic hydrocarbons (phenanthrene, fluoranthene, pyrene, chrysene benzo[a]pyrene) were chosen to this experiment and sorption process was examined on seven sediments of different properties. Chosen hydrocarbons are of different structure of molecule and different chemical and physical properties. Concentrations of polycyclic aromatic hydrocarbons in aquatic sediments and in water phase were measured in the following order: extraction with dichloromethane, concentration on rotary evaporator, silica gel clean up, n-hexane elution, concentration on rotary evaporator and in vials, GC/MS analysis. Chemical composition of aquatic sediments were examined using methods for sewage sludge and soils analysis. In every sediment concentrations of PAHs, organic matter and organic: carbon, phosphorus, nitrogen and sulphur were measured. Also fractional analysis of sediments was made. Isotherms of sorption were measured for these sediments and compounds. Equations of these isotherms were performed and were used in order to find relationships between sorption efficiency and sediments composition. Depending on sediment properties and composition different concentrations of polycyclic aromatic hydrocarbons were found in solid phase. Sediments of high quantities of organic matter and small particles were the best sorbents for PAHs. Fluoranthene, pyrene and chrysene were efficiently sorbed in sediments of high concentration of organic matter. And efficiency of phenanhrene and benzo[a]pyrene sorption were better in sediments with high quantity of organic sulphur.
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