Introduction and Objective:
The risk of cereal exposure to microbial contamination is high and possible at any time, starting from the period of plant vegetation, through harvest, up to the processing, storage and transport of the final product. Contents of mycotoxins in grain are inseparably connected with the presence of fungal biomass, the presence of which may indicate the occurrence of a fungus, and indirectly also products of its metabolism.

Material and Methods:
Analyses were conducted on 378 grain samples of wheat, triticale, barley, rye and oats collected from grain silos located at grain purchase stations and at mills in Poland in 2006, 2007 and 2008. The concentrations of ERG and mycotoxins from the group of trichothecenes, as well as CFU numbers were analysed.

Results:
The tested cereals were characterised by similarly low concentrations of both the investigated fungal metabolites and the level of microscopic fungi. However, conducted statistical analyses showed significant variation between tested treatments. Oat and rye grain contained the highest amounts of ERG, total toxins and CFU. In turn, the lowest values of investigated parameters were found in grain of wheat and triticale.

Conclusions:
Chemometric analyses, based on the results of chemical and microbiological tests, showed slight differences between contents of analysed metabolites between the years of the study, and do not confirm the observations on the significance of the effect of weather conditions on the development of mycobiota and production of mycotoxins; however, it does pertain to treatments showing no significant infestation. Highly significant correlations between contents of trichothecenes and ERG concentration (higher than in the case of the correlation of the total toxin concentrations/log cfu/g), indicate that the level of this metabolite is inseparably connected with mycotoxin contents in grain.