An analytical method for an insecticide Fipronil and its metabolite MB 46513 remaining in agricaitunil products has been established which uses GC-ECD and GC/MS for their determination and continuation, respectively. In this method, target compounds are extracted with acetone from agricultural products, concentated, and finally re-extracted with n-hexane. When the sample contains lipid in large quantity, it is first delipidated by partition with acetonitrile, cleaned up with Florisil column, and finally determined by GC-ECD. In the case of vegetables and fruits, which contain lipids in small quantity, the sample is cleaned up with a Florisil column and determined by GOECD. The detection limit of this method is 0.001 micro g/g for both of these kind of samples, the recovery of Fipronil is over 85%, and the C. V. of the recovery is less than 7%. For MB-46513. the recovery is over 63% and its C. V. is less than 9%. This method was applied to 17kinds of agricultural products and no Fipronil and MB46513 were detected.

A method by GC/MS has been established for the determination of dimethenamid and cyhalofop-butyl in agricaltural products. Dimethenamid and cyhalofop-butyl were extracted with acetone, concentrated, and re - extracted with n - hexane. The extracts were cleaned up acetonitrile partitioning and florisil column, then determined by GC/MS-SIM. This method was featured of recovery over 75% and it's C.V. below 6%. The detection limits for dimetenamid and cyharofop-butyl were 0.001 micro g/g and 0.002 micro g/g, respectively.

In Nagano Prefecture, the sudden death of many wild birds became appearent in 1997. In order to investigate the cause, the authors developed a simultaneous analytical method using GC/MS. The method was applied to investigate the reason of sudden wild bird death in 3 cases that happened in 1998. Therefore, the every cause was cleared as following. 1) In the case of Komagane City, seeds of buckwheat were found in the residues of their stomachs, and the buckwheat was subjected to analyses. A high concentration of highly toxic insecticide, Methomyl, was detected. The authors presumed that was the cause of birds' death. 2) In the case of Saku City, some flesh, probably from apples was found in the birds' stomachs. The result of flesh analysis was the highly toxic insecticide, EPN, detected in a high concentration. The authors assumed that was the cause of death. 3) In the case of Asashina Village, fish, shrimp, rice, among others were found in the birds' stomachs. The result of their analysis was the highly toxic insecticide, Benfuracarb, detected in a high concentration. The authors assumed that was the cause of death.

A micro analytical method has been established for aliphatic lower primary and secondary amines in environmental water and sediment. Amines were distilled and allowed to react with benzenesulfonyl chloride under an alkaline condition. The derivatized compounds were extracted with benzene under an acidic condition and subjected to a determination by GC/MS. This method has been successfully applied for a simultaneous determination of primary and secondary amines with recovery over 80%, except for methylamine, and C.V. below 7%, except for methyl and dimethyl amines; moreover, the detection limit were 0.1 micro g/L for all of the amines determinated. This method is excelent also in sensitivity, is sufficiently applicable to environmental samples.