The compositions of volatile organic compounds (VOCs) emitted by Fusarium fungi (F. langsethiae, F. sibiricum, F. poae, and F. sporotrichioides) grown on two nutritive substrates: potato sucrose agar (PSA) and autoclaved wheat kernels (WK) were investigated. The culturing of fungi and study of their VOC emissions were performed in chromatographic vials at room temperature (23 - 24 °C) and the VOCs were sampled by a solid-phase microextraction on a 85 μm carboxen/polydimethylsiloxane fiber. GC/MS was performed using a 60-m HP-5 capillary column. Components of the VOC mixture were identified by electron impact mass spectra and chromatographic retention indices (RIs). The most abundant components of the VOC mixture emitted by Fusarium fungi are EtOH, AcOH, (i) BuOH, 3-methylbutan-1-ol, 2-methylbutan-1-ol, ethyl 3-methylbutanoate, terpenes with M 136, sesquiterpenes with M 204 (a total of about 25), and trichodiene. It was found that the strains grown on PSA emit a wider spectrum and larger amount of VOCs compared with those grown on wheat kernels. F. langsethiae strain is the most active VOC producer on both substrates. The use of SPME and GC/MS also offers the potential for differentiation of fungal species and strains.

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The data on properties and existence forms of Russian poisonous substance VX (RVX) in environmental objects are presented. Hydrolysis of RVX with excessive amount of water in acidic medium as well as autocatalytic hydrolysis with equimolar amount of water were investigated. It was shown that in the first case destruction of RVX proceeded slower with more diverse composition of the products. Keywords: Russian poisonous substance VX (RVX), hydrolysis, gas chromatography-mass spectrometry, methylphosphonic acid, isobutyl methylphosphonic acid Substances of VX group (V-gases) are considered as the most danger chemical warfare agents of nerveconvulsing effect [1]. V-gases are low volatile liquids with high value of boiling point therefore their stability is essentially higher than stability of more volatile organophosphorus poisonous compounds such as sarin or soman. Moreover V-gases are much more toxic than the other warfare agents of nerve-convulsing effect. Thus, substance XV is approximately twice more toxic than sarin at inhalation, 10 folder more toxic at oral administration and 170 folder more toxic at topical use [2]. As a rule getting of small drops of V-gases on skin leads to lethal outcome.Under conventional designation XV the group of methylphosphonic acid O,S-diesters ROPO(CH 3 )S· (CH 2 ) 2 N(R1) 2 is conceived. О-Isobutyl-S-(2-diethylaminoethyl)methylthiophosphonate (R = i-Bu, R 1 = Et) produced since 1972 exclusively in former USSR, outside the USSR got name Russian VX (RVX, Cas #159939-87-4) has chemical formula C 11 H 26 SNPO 2 , molecular mass 276.37 a.u. and the structure presented on the figure.One of the most important tasks of ecological chemistry is investigation of behavior of highly toxic compounds in the environment. Under behavior of such compounds we imply their stability, mechanisms of possible conversions, composition of the products of the conversions and their toxicity. Among the wellknown toxicants the compounds from VX-group display probably maximal variability of the conversion mechanisms due to their unique structure. Being highly reactive and multifunctional species the compounds as constituents of multicomponent compositions are able to react with several components simultaneously. At the process the different active sites of the same molecule can be involved at the same time. Beforehand the behavior and result of such reactions can't be in all cases predicted. The problem is complicated by the fact that active components of natural or technogenic composition are not always known. Taking the above mentioned facts into account importance of the investigations dealing with identification of the conversion products of compounds of VX group in various media increases. It is supposed that destruction of the compounds is initiated by addition of an electron by the phosphorus atom as a result of the reaction with anionic nucleophile [3]. Hydroxyl anion, water, alcohols, amines, unsaturated organic compounds can serve as a nucleophile. Determination of RVX in composition of the complex m...

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