Photodegradation of fenitrothion and fenitrothion microcapsule on soil and glass surfaces was studied using the corresponding ¹⁴C-labeled preparations.
Upon exposure to sunlight, fenitrothion was degraded with the half-lives of 2 days, 2.3 weeks and 5.7 weeks on Ushiku and Ikeda soil, and on glass surface, respectively, while fenitrothion microcapsule with the half-lives of 5.5-6.5 weeks on any medium tested. The microscopic observation of the microcapsule and separate analysis of photoproducts inside/outside the microcapsule indicated that fenitrothion was photodecomposed not only inside the microcapsule but also outside the microcapsule following destruction of the wall material with subsequent elution of fenitrothion. Fenitrothion microcapsule was photodegraded in the same way as fenitrothion through oxidation of P=S to P=O, isomerization, cleavage of the P-O-aryl or P-O-methyl linkage.

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Photodegradation of fenitrothion, fenitrothion microcapsule and chlordane in water was studied, using the corresponding ¹⁴C-labeled preparations. The half-life values under sunlight were 1.1-2.6 days for fenitrothion and 3.7-5.1 days for fenitrothion microcapsule, indicating that microencapsulation retarded the fenitrothion photolysis rate by 1.9-4.4 times. Chlordane was stable to photolysis, more than 78% of the applied ¹⁴C being recovered as unchanged parent compound after 14 days. The microscopic observation of the microcapsule and separate analysis of photodegradation products inside/outside the microcapsule indicated that fenitrothion was photodecomposed not only inside the microcapsule but also outside the microcapsule following destruction of the wall material with subsequent elution of fenitrothion into the surrounding water. Fenitrothion microcapsule was photodegraded in the same way as fenitrothion through oxidation of P=S to P=O, oxidation of the aryl methyl group to the carboxyl group, reduction of the nitro group to the amino group, coupling of the carboxyl group with the amino group leading to the formation of the dimeric compound, isomerization, cleavage of the P-O-aryl or P-O-methyl linkage, substitution of the nitro group by the hydroxyl group and photomineralization of the aromatic ring to carbon dioxide.

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In this paper a method for the quantative analysis of the absorption of treated timber with Chrome-Copper-Arenic preservative (CCA), by X-ray fluorescence analyser was reported.
The analytical method from treated wood for X-ray fluoresence analysis were as follows. The sawdust was firstly dried by the oven and was grounded by a ball mill and then was redried overnight. The grounded powder was pressed for the tablet.
On the all of data obtained, there were not so muth difference in the analytical-valuecs between atomic absorption spectrophotometry method and X-ray fluoresence method.
Samles of solution could be directly in a Mylar cell.
The results obtained indicate that the X-ray fluoresence analysis can be used for the quality control of treating solution and treated wood in the treatmentf indnctrv with CCA.

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