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The paper presents the results of laboratory monitoring pesticide residues in the environment in the Republic of Mordovia in 2000 to 2007. It gives examples how to determine organic chlorine pesticides in the foodstuffs and environment, by stating the concentrations of ingredients. The entry route of pesticides and their action on human beings are shown. The main preventive measures are indicated for persons handling pesticides.

Data on the contents of protein, fats and toxic compounds (PCB, DDT, gamma-Lindane) in breast milk Russian and Vietnamese women after timely and premature childbed are resulted. The contents of protein in transitive milk was higher than in mature milk, both timely childbed and premature one. The contents of protein in nature milk of the Vietnamese women was lower, than in mature milk of the Russian women (12 g/l against 16.5 g/l accordingly). The contents of fat in breast milk of the Russian women in lactation increased. Vietnamese women had very low fat level in mature milk (29 g/l against 42 g/l at the Russian women). The contents of toxic compounds (PCB, DDT, gamma-Lindane) in breast milk both, Vietnamese women and Russian women was rather high and significant frequency of detection of these compounds in milk was marked. The correlation contents of basic food components in breast milk and level of toxic compounds was absent.

The work was aimed at studying the degradation of DDT, its metabolites and analogs by BS 816 and BS 827 strains constructed on the basis of Pseudomonas aeruginosa 640x strains and carrying biodegradation plasmids pBS2 and pBS3, respectively. DDT and kelthane were degraded by the BS 816 strain at a greater rate than by the parent culture. The investigation of enzymes involved in the oxidation of the aromatic cycle has shown that the plasmid-carrying strains possess the activity of metapyrocatechase and salicylate hydroxylase which is absent in P. aeruginosa 640x. The activity of pyrocatechase increased. In contrast to the parent strain where homogentisate induced only homogentisate oxygenase, this compound induces also metapyrocatechase in the constructed strains.

The distribution of residues of DDT and its metabolites (DDD and DDE) in tissues of Triaenophorus nodulosus and its host was studied. It has been noted that cestodes can accumulate chlororganic substances in great quantity. The ability of Bothriocephalus gowkongensis has been established to dechlorate pp-DDT and to excrete pp-, op- and mp-DDD from the organism. Pp-DDT decreases the glycogene content and causes the rise of amylolytic activity in the above cestodes in acute tests. The effect of pp-DDT on the locomotor activity of cestodes is of two-phase character. The first one is associated with the muscular influence, the second one-- with neurotrophic effect. A high toxicity of mp-DDD )0.1 mg/l) for the locomotor activity of cestodes as compared with the effect of pp- and op-DDD was revealed.

In tests on Wistar male-rats the toxic action and redistribution of the DDT repository in the fatty tissue were investigated. For this purpose a DDT depot was built up by introducing DDT in a dose of 0.2 mg/kg for a period of 6 months, following which the rats were made to fast for 20 days, this securing the egress of DDT from the depot. Furthermore, some of the rats, once the depot had been built up, were for 1 month put on a ration containing 5 per cent of protein and then subjected to fasting for 20 days, this having been done in order to study the toxic effect of DDT against the background of a diet with a low protein content. It was found that the amount of DDT retained in the organs and tissues (omentum, liver, brain) investigated in the test rats did not exceed 10 per cent of the quantity that had been introduced at the time of building up the depot. At the time of fasting there was noted migration of DDT from the fat depot, it being the same both in the test and control animals. But DDT coming from the DDT repository entered the liver and brain only in the test animals, provoking changes in the activity of a number of enzymes in these organs. A low protein diet somewhat intensified these changes.

The object of this work was to investigate the operation of enzymes of the citric acid cycle, the glyoxylate pathway, the glucose metabolism as well as of pyruvate and phosphoenolpyruvate carboxylases in Pseudomonas aeruginosa 640x capable of complete degradation of DDT under the conditions of cometabolism. The activity of isocitrate and glucose-6-phosphate dehydrogenases producing reduced NADP, which is required for reductive dechlorination of DDT, appears to be high. Pyruvate carboxylase and phosphoenolpyruvate carboxylase (EC 4.1.1.31.) function simultaneously in the culture. Differences in the pathways of anaplerotic carbon dioxide fixation were found in P. aeruginosa 640x and the collection strain of P. aeruginosa PAO incapable of DDT degradation.

The purpose of this work was to study the process of oxidation of aromatic acids (benzoic, salicylic and phenylacetic acids) produced as the result of DDT degradation by Pseudomonas aeruginosa 640x. The cultural broth was analysed by thin-layer chromatography, chromato-mass spectrometry and the enzymes of aromatic acid oxidation were investigated. Benzoate was shown to be oxidized via p-hydroxybenzoic acid, protocatechuic acid and its ortho degradation. Phenylacetate, the principal of DDT degradation, was hydroxylated by the culture with simultaneous migration of the two-carbon fragment and decomposition of the resultant homogentisic acid. Salicylic acid was not oxidized by the culture; it was accumulated in the medium. Analysis of the enzymes involved in the oxidation of the aromatic cycle has shown that the culture lacks salicylate hydroxylase, metapyrocatechase and gentisate 1,2-dioxygenase. Instead, it manifested the activities of the enzymes catalysing ortho cleavage of the cycle, namely, pyrocatechase and protocatechoate 3 : 4 dioxygenase, as well as homogentisate oxygenase.

The activity of enzymes was compared during Pseudomonas aeruginosa 640x growth on compounds activating DDT to a different degree and on acetate which did not stimulate this process. The activity of dehydrogenases generating reduced cofactors necessary for DDT dechlorination was found to be much higher on effective additional substrates than on compounds which either had no effect on DDT degradation or stimulated this process only slightly. The activity of enzymes generating the reduced cofactors was shown to correlate with the extent of DDT degradation by this culture.