A research on a treatment system of human excreta provided for the use in mountainous areas was carried out. The system was composed of two treatment processes, an anaerobic digestion and a seepage spray process. Vertical distributions of chemical components were observed in the anaerobic digestion tank, because the top of the tank was covered with water permeable phase and rain water was penetrated into the tank. Comparing the amount of inflow into and of evapotranspiration from the system, about 70% of the inflow was overflowed from the seepage spray tank, under the assumption that the whole rain water fallen on the system was permeated into it.

Many complaints have been made about bad smelling and tasting food and accidents resulting in the death of animals in Nagano Prefecture. The method of headspace SPME-GC/MS has been found very effective as a screening method to investigate the cause of these complaints and accidents. This method is characterized mainly in that the operation is simple without using any solvents for extraction, causing no environmental pollution; the extraction may be carried out in a short time with a small quantity of sample in low concentration, preventing reagent contamination, the whole extract may be injected, leading to high sensitivity, and the fiber may be used repeatedly, making the analytical cost inexpensive. This paper describes representative examples of cases in which the relevant causes have been solved.

An investigation was made to find analytical method for anilazine and propazine remaining in agricultural products. Since anilazine was found to be decomposed enzymatically when applied on cabbage, radish, etc., phosphoric acid was added to the sample to suppress the enzymatic activity before subjecting the sample to an extraction with acetone. The extract was re-extracted into n-hexane, cleaned up with a Florisil column, and finally subjected to a determination with ECD-GC. Propazine was found to be insusceptable to any enzymatic decomposition, but it was subjected to the same acetone extraction and n-hexane re-extraction as with anilazine, separated from anilazine with a Florisil column, and subjected to a determination with NPD-GC. The detection limits of these methods are 0.01 micro g/g for both anilazine and propazine. The addition-recovery experiments conducted resulted in recoveries of over 79 and 82% with coefficient of variation of less than 5.6 and 5.5% for alilazine and propazine, respectively (n=5). The present methods were applied to actual agricultural products, with neither anilazine nor propazine detected (n=22).