[Selection of GC phases and optimization of separation of trichothecenes by means of computer simulation]. / Auswahl von GC-Phasen und Optimierung von Trichothecen-Trennungen mittels Computersimulation.

Gas chromatography combines high resolution with good sensitivity (ECD) for the simultaneous analysis of trichothecenes. With the aid of computer-supported GC simulation based on thermodynamic retention indices, optimized GC methods for 4 different phase polarities have been developed. The verification with polar and unpolar columns in 2 GCs under optimized separation conditions provides highly reliable results.

[Not Available]. / Shifting von Fusarienarten und ihren Toxinen in österreichischem Getreide.

Based on representative analyses of Austrian cereals, a distinct shift in the spectrum of Fusarium toxins and Fusarium species has been observed since the middle of the eighties.Although in the case of maizeF subglutinans - apart fromF graminearum - proved to be the most frequent and constant contaminant over the entire range of test series, there has been a shift in the spectrum of species which is not to be explained simply by seasonal variations or by the varying degree of occurrence of the European corn borer, which in Austria is considered to be the main vector for infections involving fusaria of the Liseola section. Compared to the results from earlier vegetation periods, the nineties brought a significant increase in the number of infections withF proliferatum, a fumonisin-producer. In all likelihood, this shift in the spectrum of species is due to the changed climatic conditions now prevailing in Austria - milder and more humid winters vs. drier and warmer summers - which favour the progress ofF proliferatum.The principal toxin-forming fungus on cereals in Austria isF graminearum. On maize, its respective populations are exclusively those which produce 15-acetyl-DON as a precursor to DON (deoxynivalenol). Whilst in the 1980s,F graminearum isolates from wheat yielded both 15-acetyl-DON and 3-acetyl-DON types, only 15-acetyl-DON populations could be detected in the last few years. One possible explanation for this phenomenon is the continual intensification of maize-wheat crop rotations. In the light of the above observations, the frequently used argument whereby EuropeanF graminearum isolates produce mainly 3-acetyl-DON and American strains prevalently 15-acetyl-DON will have to be reviewed.

Occurrence of moniliformin, deoxynivalenol, and zearalenone in durum wheat (Triticum durum Desf.).

Forty-eight durum wheat samples from 5 locations in Austria were examined forFusarium infection andFusarium toxin content.F.gramlnearum andF.avenaceum were by far the prevailingFusarium species In durum wheat kernels, followed byEpoae, F.culmorum, andF.equlsetl. Ion-paired HPLC analyses of the samples showed moniliformin contents of kernels up to 0.88 mg/kg. All moniliformin contaminated samples also contained high levels of deoxynivalenol (up to 8.2 mg/kg) and lower levels of zearalenone (<0.33 mg/kg). The levels of zearalenone in naturally contaminated durum wheat samples did not correspond to the high yields of zearalenone found in cultures of the fusaria isolated from the durum wheat kernels. These conflicting results as well as some toxicologlcal aspects of the carry over ofFusarium toxins from durum wheat kernels into pasta are discussed.

Occurrence of organic pollutants in the soil of upper Austria.

In the course of a study of soil quality over 200 soil samples were collected in an Austrian province and analyzed for residues of organochlorine pesticides, selected PCB congeners, triazine herbicides and selected polycyclic aromatic hydrocarbons. Concentrations of these compounds were found to vary within a broad range. This holds true especially for polycyclic aromatic hydrocarbons. The results are set into relation to the agricultural use of soils, the intensity of nearby road traffic and population density.