Photodegradation of phosmet in wool wax models and on sheep wool: determination of wool wax bound phosmet by means of isotope ratio mass spectrometry

The photochemical reactions of phosmet, an organophosphorus insecticide used for plant protection and for control of ectoparasites on productive livestock, were studied in the presence of wool wax. Induced by UV light, phosmet features numerous degradation pathways as well as photoaddition reactions with lipid structure moieties. In model irradiation experiments of phosmet in mixtures of solvents (cyclohexane, cyclohexene, 2-propanol) and fatty acid methyl esters (methyl stearate, methyl oleate, 12-hydroxymethyl stearate), both adjusted to the hydroxyl and iodine values of wool wax, half-lives were determined to be approximately 7 and 16 h, respectively. Irradiation of phosmet on crude sheep wool resulted in a degradation rate of 65% after 24 h. In tracer studies with stable isotope labeled phosmet ([15N]phosmet) in commercial lanolin and on raw sheep wool, employing a sunlight simulator and natural sunlight, wool wax bound phosmet was formed. After extraction and measurement by elemental analyzer/isotope ratio mass spectrometry, delta15N values of the phosmet-free wool wax fractions were notably increased as compared to the value of natural lanolin. Calculated from the delta15N values, an average of 13.9/15.6% (sunlight simulator/natural sunlight) was bound to wool wax lipids after irradiation of thin films of commercial lanolin. In experiments with sheep wool, 13.2 and 15.4%, respectively, were detected as wax-bound.     

Photolysis experiments on phosmet, an organophosphorus insecticide

The organophosphorus insecticide phosmet is used in plant protection as well as against parasites on animals. Phosmet showed numerous photoinduced reaction pathways, which first were studied in the presence of model environments for animal fur lipids (e.g., wool wax). The model solvents for saturated and unsaturated lipids were cyclohexane and cyclohexene, whereas methanol and 2-propanol were used as models for primary and secondary alcohol moieties of lipids. The measured degradation rates over an irradiation period of 7 h in all solvents used were very similar (49-55%). The obtained photoproducts generally included phthalimide, N-hydroxymethylphthalimide, and N-methoxymethylphthalimide. Furthermore, depending on the solvent used, additional degradation products were detectable as N-isopropoxy- and N-methylphthalimide in the presence of 2-propanol and cyclohexene, respectively. However, in the presence of cyclohexene, despite the similar turnover, distinctly lower concentrations of photoproducts were found, indicating further still unknown degradation pathways. Irradiations in methanol with increasing percentages of water led to higher degradation rates; however, the products were found to be the same. Irradiation experiments with pure phosmet on silica TLC plates and glass surfaces resulted in degradation rates of 19 and 32%, respectively, after 6 h. The results obtained clearly demonstrate for the first time that the photoinduced degradation of phosmet is strongly dependent on the chemical environment, affecting less the turnover than the photoproducts formed. The results additionally demonstrate the need to investigate the degradation behavior of phosmet on wool and in the presence of wool wax.     

Photochemistry of imidacloprid in model systems

The photochemical behavior of the neonicotinoid insecticide imidacloprid was studied with regard to different chemical environments. Different model solvents simulated the structure moieties mainly occurring in waxes and cutin of the plant cuticle. Cyclohexane and cyclohexene substituted saturated and unsaturated hydrocarbon chains, whereas ethanol and 2-propanol were models for primary and secondary alcohol groups of cuticular components. After 5 h of irradiation, imidacloprid was completely degraded in all solvents. With 88-96 mol% 1-[(6-chloropyridin-3-yl)methyl]imidazolidin-2-imine was formed as the main product, whereas 1-[(6-chloropyridin-3-yl)methyl]imidazolidin-2-one was identified as minor product in the range 4-6 mol%. By contrast, besides the photoproducts formed in organic solvents, irradiation of the solid imidacloprid on a glass surface delivered a complex variety of unidentified photoproducts. The nucleophilic addition reaction of the main photoproduct, 1-[(6-chloropyridin-3-yl)methyl]imidazolidin-2-imine, with both cyclohexene oxide and methyl 9,10-epoxystearate as model compounds indicates that epoxidized cutin acids are possible reaction partners for the formation of plant cuticle bound residues of imidacloprid, which could explain the reported findings of nonextractable residues of imidacloprid in plants.     

Formation of polycyclic aromatic hydrocarbons in the smoke from heated model lipids and food lipids.

The contents of polycyclic aromatic hydrocarbons (PAHs) in the smoke from model lipids and food lipids during heating were determined and the mechanism of PAH formation was studied. A Rancimat oil stability analyzer was used as a model system for heating model lipids and food lipids at 220 degrees C for 2 h and for adsorption of smoke. The various lipid degradation products and PAHs in the smoke were identified and quantified by a GC/MS technique. Results showed that model lipids were more susceptible to smoke formation than food lipids during heating, but the PAH levels were lower for the former than latter. Methyl linolenate produced the highest amount of PAHs, followed by methyl linoleate, methyl oleate, and methyl stearate. Also, soybean oil generated a larger amount of PAHs than canola oil or sunflower oil. Benzene-like compounds were found to be possible precursors for PAHs formation. Several PAH derivatives were also present in heated model lipids and food lipids.     

Effects of postharvest preparation on organophosphate insecticide residues in apples

Apples were sampled directly from orchard trees at 96, 45, and 21 days postapplication with one of three organophosphate insecticides (azinphos methyl, phosalone, or phosmet, respectively). Individual apples were prepared for analysis following one of three postharvest preparations: no preparation, rinsed with deionized water for 10-15 s, or rinsed and peeled. Azinphos methyl, phosalone, and phosmet concentrations ranged from below the level of detection to 5.26 ng/g, 94.7 to 5720 ng/g, and 0.011 to 663 ng/g in the apples that received no postharvest preparation, respectively. Although rinsed apples had lower maximum concentrations than observed in apples with no preparation, levels were not significantly lower. Concentrations of all three OP insecticides in apples that were rinsed followed by peeling, however, were much lower (below detection limits to 0.733 ng/g, azinphos methyl; 0.322-219 ng/g, phosalone; and below detection limits to 44.0 ng/g, phosmet) than observed in apples that had been rinsed alone. Rinsing and peeling of apples resulted in a 74.5-97.9% reduction in OP residues, while rinsing alone lowered mean concentrations by 13.5-28.7% relative to apples that received no postharvest preparation.     

Bound fumonisin B1: analysis of fumonisin-B1 glyco and amino acid conjugates by liquid chromatography-electrospray ionization-tandem mass spectrometry

To study the formation of fumonisin artifacts and the binding of fumonisins to matrix components (e.g., saccharides and proteins) in thermal-treated food, model experiments were performed. Fumonisin B(1) and hydrolyzed fumonisin B(1) were incubated with alpha-d-glucose and sucrose (mono- and disaccharide models), with methyl alpha-d-glucopyranoside (starch model), and with the amino acid derivatives N-alpha-acetyl-l-lysine methyl ester and BOC-l-cysteine methyl ester (protein models). The reaction products formed were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry. The incubation of d-glucose with fumonisin B(1) or hydrolyzed fumonisin B(1) resulted in the formation of Amadori rearrangement products. Whereas conjugates were found following the reaction of sucrose, methyl alpha-d-glucopyranoside, and the amino acid derivatives with fumonisin B(1), the heating with hydrolyzed fumonisin B(1) yielded no artifacts. For structural determination, the stable reaction product formed by heating of methyl alpha-d-glucopyranoside (as starch model) with fumonisin B(1) was purified and identified by nuclear magnetic resonance spectroscopy as the diester of the fumonisin tricarballylic acid side chains with methyl alpha-d-glucopyranoside. These model experiments demonstrate that fumonisins are able to bind to polysaccharides and proteins via their two tricarballylic acid side chains.     

Evaluation of residual levels of benomyl, methyl parathion, diuron, and vamidothion in pineapple pulp and bagasse (Smooth cayenne)

The objective of this research was to study the residual levels of benomyl, methyl parathion, diuron, and vamidothion in pineapple bagasse and pulp. Benomyl (benlate), methyl parathion (Folidol 600), diuron (Krovar), and Vamidothion (Kilval 300) were applied pre-harvest to pineapples (smooth cayenne). After harvesting, the fruits were washed (100 ppm sodium hypochlorite) and the pulp was separated from the sub-products (peel, core, tops, and tails). The pulp was not submitted to any heat treatment. The sub-products and the juice expressed from them, were submitted to a blanching process (95 degrees C for 1 min). After separating the juice, the bagasse and pulp were analyzed for residues of diuron and benomyl by high performance liquid chromatography, and for residues of vamidothion and methyl parathion by gas chromatography using a TSD detector. No residues of benomyl, diuron, vamidothion, or methyl parathion were detected in the pulp within the quantification limits of the methods (0.1 mg/kg, 0.1 mg/kg, 0.005 mg/kg, and 0.005 mg/kg, respectively). Only methyl parathion (0.052 mg/kg) and vamidothion (0.021 mg/kg) were detected in the bagasse. The presence of these residues in the bagasse was probably due to the action of the wax found in the peel, which prevented the methyl parathion and vamidothion from dissolving in the juice. According to these results, the pulp was fit for human consumption, as far as pesticide residues were concerned, and the bagasse was fit for animal feed and similar applications, because the residual levels found were below the limits established for these compounds.     

Methyl linoleate oxidation in the presence of bovine serum albumin

The oxidation of methyl linoleate (LMe) in the presence of bovine serum albumin (BSA) was studied to analyze both the processes involved when lipid oxidation occurs in the presence of proteins and the relative progression of the several reactions implicated. The disappearance of LMe, the formation of primary and secondary lipid oxidation products, the loss of essential amino acids, and the production of oxidized lipid/amino acid reaction products (OLAARPs) were studied as a function of incubation time. During the first steps of lipid oxidation, LMe was converted quantitatively to methyl linoleate hydroperoxides, which were very rapidly degraded to either secondary products of lipid oxidation or OLAARPs. No significant differences were identified in the major lipid oxidation products formed in incubations with or without proteins, indicating that mechanisms for formation of these compounds are similar in both cases. In addition, no significant differences were observed between the time-courses of formation of secondary oxidation products and OLAARPs, suggesting that hydroperoxide decomposition and OLAARP formation occur simultaneously when the lipid oxidation process takes place in the presence of proteins. Furthermore, OLAARP formation seems to be an unavoidable process that should be considered as a last step in the lipid peroxidation process.     

Evaluation of chemical and photochemical oxidation processes for degradation of phosmet on lowbush blueberries (Vaccinium angustifolium)

Chemical and photochemical oxidation processes were evaluated for their ability to degrade residual phosmet on lowbush blueberries and for their role in the conversion of phosmet to phosmet oxon--a toxic metabolite of phosmet. Chemical processes included 1 ppm of aqueous ozone, 1% hydrogen peroxide, 100 ppm of chlorine, and UV, whereas photochemical processes included hydrogen peroxide/UV, chlorine/UV, and ozone/hydrogen peroxide/UV. Phosmet applied as Imidan 2.5EC under laboratory conditions resulted in a mean residual concentration of 44.4 ppm, which was significantly degraded (p < 0.05) by ozone and chlorine, yielding reductions of 57.7 and 46%, respectively. Interaction between phosmet (Imidan 2.5EC) and any chemical or photochemical treatment did not result in conversion to phosmet oxon. Residual analysis of commercially grown blueberries revealed mean phosmet (Imidan 70W) levels of 10.65 ppm and phosmet oxon levels of 12.49 ppm. Treatment of commercial blueberries resulted in significant reductions in phosmet regardless of treatment type; however, only UV, hydrogen peroxide/UV, and ozone treatments degraded phosmet (Imidan 70W) to less toxic metabolites and reduced phosmet oxon levels. Treatment-induced conversion of phosmet to phosmet oxon was noticeably influenced by variations between phosmet formulations. Acceleration of photochemical degradation by UV was not observed. Selective oxidation by ozone represents a significant postharvest process for degrading residual phosmet on lowbush blueberries.     

Determination of benzene in polypropylene food-packaging materials and food-contact paraffin waxes

An analytical procedure was developed for determination of benzene in polypropylene food packaging and was adapted for determination of benzene in commercial paraffin waxes intended for food-contact use. The polymer was dissolved in hexadecane at 150 degrees C. The wax was melted in an 80 degrees C oven. A simple helium-sparging apparatus was used to remove the volatile chemical from the polymer or wax. The contaminant was collected in methanol, distilled water was added, and the resulting solution was analyzed by headspace gas chromatography. The instrument was equipped with a 30 m fused silica open tubular capillary column and a photoionization detector. Average recoveries of benzene from polymer and paraffin wax at low parts-per-billion concentrations were 63 and 70%, respectively. Limits of detection and quantitation for analysis of polypropylene were 8 and 17 ppb, respectively; the limit of quantitation for analysis of paraffin wax was 2 ppb. In several commercial polypropylene products examined, benzene levels ranged from none detected to 426 ppb. In 3 commercial waxes examined, concentrations of 16-73 ppb benzene were determined. The presence of benzene was confirmed by gas chromatography/mass spectrometry.     

利用热力学相平衡分析生物柴油晶体析出规律

生物柴油主要是由饱和脂肪酸甲酯和不饱和脂肪酸甲酯组成的混合溶液,从热力学角度分析,生物柴油的蜡晶析出是溶液由液相向固相转变的相平衡过程。该文建立将液相组成作为理想溶液且固相成分不互溶的理想溶液模型（模型一）和基于活度系数模型与正规溶液理论的正规溶液模型(模型二),分别计算了蜡晶的析出温度,并且通过模型二计算出在给定的温度下的析蜡量与石蜡的组成。两模型在计算析蜡点的温度精确性方面还是比较理想的误差在5 K左右。研究发现石蜡沉积量与饱和脂肪酸酯的量成一定的比例关系,而且石蜡沉积并不是按照脂肪酸酯熔点高低的顺序进行析出,析出的石蜡中同时包含了低熔点脂肪酸酯。固液平衡常数是表征物质在溶液中析出能力的决定性因素,在一定温度下,不饱和脂肪酸酯的固液平衡常数一般在0.1以下,而饱和脂肪酸酯的固液平衡常数却大得多。该研究阐明的晶体析出规律,可为优化生物柴油低温流动性技术措施,推动生物柴油在低温环境下的应用提供参考。     

p-Hydroxybenzoic acid alkyl esters in Andrographis paniculata herbs,commercial extracts,and formulated products

Analysis of two commercial extracts of Andrographis paniculata using high-performance liquid chromatography (HPLC) with photodiode array absorbance detection showed the presence of several unexpected compounds, which were isolated and identified as methyl, ethyl, and propyl esters of p-hydroxybenzoic acid by using high-resolution mass spectrometry and nuclear magnetic resonance. Quantitative analysis using HPLC revealed the presence of 0.22% p-hydroxybenzoic acid methyl ester (methlyparaben) in one commercial extract, and both 0.11% p-hydroxybenzoic acid ethyl ester (ethylparaben) and 0.20% p-hydroxybenzoic acid propyl ester (propylparaben) in a second commercial extract of A. paniculata. Analyses of additional commercial products of A. paniculata in tablet form purchased from Chicago pharmacies also showed the presence of methyl- and ethylparabens. To determine whether these compounds were natural chemical constituents of the plant, pharmacopoeial reference A. paniculata plant powder as well as samples of authenticated A. paniculata plant materials collected from Indonesia, Hong Kong, and mainland China were obtained and analyzed by HPLC-tandem mass spectrometry (LC-MS-MS). LC-MS-MS analyses confirmed the presence of trace concentrations (<0.0008% w/w) of p-hydroxybenzoic acid methyl ester but no p-hydroxybenzoic acid ethyl or propyl esters in these plant samples. The limits of detection of the LC-MS-MS assay for these compounds were 5 pg on-column and 5 ppb in the plant material. The levels of these p-hydroxybenzoic acid esters measured in the commercial products of A. paniculata suggest that they were introduced inadvertently during processing or as artificial additives.     

Effect of pH and temperature on comparative nonenzymatic browning of proteins produced by oxidized lipids and carbohydrates

Bovine serum albumin (BSA) was incubated for 24 h in the presence of 10 mM ribose (RI), methyl linoleate hydroperoxides, or the secondary products of methyl linoleate oxidation (SP), at five temperatures (25, 37, 50, 80, and 120 degrees C) and different pHs (4, 7, and 10), to study the influence of these variables in the browning, fluorescence, amino acid losses, and pyrrolization of the modified proteins. All treated proteins exhibited similar colors and fluorescence spectra, and the spectra of their Ehrlich adducts were also analogous. However, at 25-50 degrees C the proteins treated with oxidized lipids exhibited higher color changes, amino acid losses, and pyrrolization than the BSA treated with RI, and these effects were much higher in proteins treated with RI at 80-120 degrees C. The effect of pH was similar in proteins treated with RI or SP. These results suggested a similarity for browned proteins obtained from both carbohydrates and oxidized lipids. In addition, both reactions seem to be complementary, because melanoidin formation derived from oxidized lipids can be produced under conditions different from those carbohydrate/protein reactions.     

Determination of the wax ester content in olive oils. Improvement in the method proposed by EEC regulation 183/93

A simpler and faster procedure than the official one described in document IV of European Economic Community Regulation 183/93 is proposed. The wax ester fraction is isolated from triglycerides using a commercially available silica gel column and carbon tetrachloride as eluent. The recovered wax ester fraction, with the addition of a suitable internal standard solution, is analyzed by gas chromatography. A column with a 65% phenyl methyl silicone stationary phase allows a satisfying separation of wax ester fraction in comparison with both a steryl ester and a light fraction eluted before the internal standard. Furthermore, also the single components of the wax ester fraction are suitably separated.     

Permanganate oxidation of methylated and non-methylated aquatic humus in Norway

The chemical composition of aquatic humus was investigated by permanganate oxidation. Both methylated and non-methylated samples were investigated and the results compared with those of different soil humic fractions investigated earlier.The total amount of oxidation products identified from the methylated sample was 2%, and from the non-methylated sample 0.9%. The composition of the oxidation products from methylated aquatic humus was 42% benzenecarboxylic acid methyl esters (8 different compounds), 43% methoxy-benzenecarboxylic acid methyl esters (12 compounds), 10% dimethoxy-benzenecarboxylic acid methyl esters (4 compounds), and 5% of 1, 2, 3-propanetricarboxylic acid trimethyl ester. The unmethylated aquatic humus yielded 84% benzenecarboxylic acid methyl ester (7 compounds), 7% methoxy-benzenecarboxylic acid methyl esters (2 compounds), and 9% of 1, 2, 3-propanetricarboxylic acid trimethyl ester. Three diazines isolated from methylated material were believed to be artefacts from diazomethane treatment. Two of the diazines have earlier been found by oxidation of methylated soil samples, the third, C₁₀H₁₂N₂O₆, is an oxidation product of methylated aquatic humus only.Oxidation of aquatic humus yielded more benzenecarboxylic acids and methoxy-benzenecarboxylic acids than soil humic fractions, and less dimethoxy-benzenecarboxylic acids. No aliphatic dicarboxylic acids were detected among the oxidation products of the aquatic humus.The compounds identified are mainly the same as those found by oxidation of different soil humic fractions, although their yields clearly demonstrated that the aquatic humus differed in composition from the soil fractions.     

Isobaric labeling approach to the tracking and relative quantitation of peptide damage at the primary structural level

Protein oxidative damage lies behind skin and hair degradation and the deterioration of protein-based products, such as wool and meat, in addition to a range of serious health problems. Effective strategies to ameliorate degenerative processes require detailed fundamental knowledge of the chemistry at the molecular level, including specific residue-level products and their relative abundance. This paper presents a new means of tracking damage-induced side-chain modification in peptides using a novel application for isobaric label quantification. Following exposure to heat and UVA and UVB irradiation, tryptophan and tyrosine damage products in synthetic peptides were characterized and tracked using ESI-MS/MS and iTRAQ labeling-based relative quantification. An in-depth degradation profile of these peptides was generated, enabling the formation of even low-abundance single-residue-level modifications to be sensitively monitored. The development of this novel approach to profiling and tracking residue-level protein damage offers significant potential for application in the development and validation of protein protection treatments.     

Chemical composition of Greek avgotaracho prepared from mullet (Mugil cephalus): nutritional and health benefits

Crude composition, lipid composition, and tocopherols, ascorbic acid, cholesterol, phytosterols, and squalene content together with fatty acids and antiplatelet activities of total, neutral, and polar lipids of avgotaracho (wax-covered, dried, and salted Mugil cephalus roe) were studied and compared with those of similar products. Wax and steryl esters accounted for 63.7% of roe lipids followed by phosphatidylcholine (PC), which comprised 20.3%. Wax esters were rich in saturated fatty alcohols, monounsaturated fatty acids, and long chain omega3 highly unsaturated fatty acids (HUFA). The fatty acid distribution in roe total and neutral lipids was similar to that of wax esters, while in polar lipids, the omega3 HUFA predominated. Avgotaracho provides significant amounts of protein, fat, alpha-tocopherol, ascorbic acid, and PC, certain amounts of squalene and phytosterols, and cholesterol at levels comparable to hens' eggs. Total, polar, and neutral lipids of avgotaracho exhibited a strong inhibition of platelet activating factors and thrombin, with polar lipids being more active. The results obtained indicate that avgotaracho is a food of high nutritive value, rich in protein and lipids with a healthy lipid profile in terms of omega3/omega6 ratio and major fatty acid classes, while the antiplatelet activity of its oil indicates a putative antithrombotic potential.     

Phytotoxic Effect of Landfill Leachate with Different Pollution Indexes on Common Bean

The degradation of methyl orange (MO) in aqueous solution by microwave irradiation in the presence of granular-active carbon (GAC) was investigated. It was found that a synergistic rather than an additive effect of microwave irradiation and GAC contributes to the high-degradation efficiency. The ultraviolet and visible spectrum (UV–vis), infrared spectroscopy (IR), and scanning electron microscopy (SEM) measurements were conducted to trace the MO degradation process. It was demonstrated that the decrease in performance of GAC after repetitive use is largely attributed to the adsorption of some intermediate products on the surface of GAC. The regeneration of the spent GAC under microwave radiation was also investigated. The results show that the activity of spent GAC can be effectively recovered by microwave radiation and 74.1 % of its initial activity remains after six reaction cycles.     

Contribution of lipid oxidation products to acrylamide formation in model systems

The reactions of asparagine with methyl linoleate ( 1), methyl 13-hydroperoxyoctadeca-9,11-dienoate ( 2), methyl 13-hydroxyoctadeca-9,11-dienoate ( 3), methyl 13-oxooctadeca-9,11-dienoate ( 4), methyl 9,10-epoxy-13-hydroxy-11-octadecenoate ( 5), methyl 9,10-epoxy-13-oxo-11-octadecenoate ( 6), 2,4-decadienal ( 7), 2-octenal ( 8), 4,5-epoxy-2-decenal ( 9), and benzaldehyde ( 10) were studied to determine the potential contribution of lipid derivatives to acrylamide formation in heated foodstuffs. Reaction mixtures were heated in sealed tubes for 10 min at 180 degrees C under nitrogen. The reactivity of the assayed compounds was 7 > 9 > 4 > 2 > 8 approximately 6 > 10 approximately 5. The presence of compounds 1 and 3 did not result in the formation of acrylamide. These results suggested that alpha,beta,gamma,delta-diunsaturated carbonyl compounds were the most reactive compounds for this reaction followed by lipid hydroperoxides, more likely as a consequence of the thermal decomposition of these last compounds to produce alpha,beta,gamma,delta-diunsaturated carbonyl compounds. However, in the presence of glucose this reactivity changed, and compound 1/glucose mixtures showed a positive synergism (synergism factor = 1.6), which was observed neither in methyl stearate/glucose mixtures nor in the presence of antioxidants. This synergism is proposed to be a consequence of the formation of free radicals during the asparagine/glucose Maillard reaction, which oxidized the lipid and facilitated its reaction with the amino acid. These results suggest that both unoxidized and oxidized lipids are able to contribute to the conversion of asparagine into acrylamide, but unoxidized lipids need to be oxidized as a preliminary step.     

Ion chromatographic determination of the decomposition products of tecnazene solution irradiated by ultraviolet light: inorganic and organic anions.

Ion chromatographic (IC) methods using sodium hydroxide and methanol gradients were used for the determination of small inorganic and organic anions as decomposition products of a tecnazene solution in water irradiated by UV light. After 60 min of UV irradiation, >99% of the tecnazene was decomposed, and 11 organic and 3 inorganic anions were identified and quantified. A fourth inorganic anion, carbonate, was not quantified due to likely losses as carbon dioxide. The final content of chloride, total nitrogen, and total carbon released from the saturated tecnazene solution after 60 min of UV irradiation were 108, 85, and 38%, respectively. These results suggest that other products rich in carbon and/or nitrogen (such as phenolic compounds and nitrobenzenes) were formed during the UV irradiation of the tecnazene solution. The results obtained indicate several decomposition pathways of tecnazene in water solutions, for example, ring opening reactions, dechlorination, and replacement of the ring nitro group. The determination of nonionic decomposition products from the latter two possibilities is the subject of further study.