Toshihiko Seki

Study on Pollution of Organotin Compounds in Sendai Bay

There are two analytical methods for determination of organotin (tributyltin compounds (TBT) and triphenyltin (TPT) in environmental samples. The first method is performed by ECD-GC with a column treated with hydrobromic acid. The second method is performed by FPD-GC of alkylated samples. The analytical operation of the first method was mere simple than that of the second method, while the recovery (above 90%) and reproducibility (CV, below 5%) of the first method were almost same as those of the second method. From the results, we used the first method for analysis of organotin compounds in environmental samples. To clarify the pollution of organotin compounds in Sendai Bay, samples were collected from eight stations in the Bay, and were analyzed. The results showed that the inside of Sendai Port was more polluted with organotin compounds from ship-paints than the outside.

Simplified determination of diphenyl ether herbicides with SEP-PAK cartridge.

Simplified methods with SEP-PAK cartridges (Waters Associates) for the determination of diphenyl ether herbicides (CNP, NIP, X-52) in various samples, i. e. water, fish and river sediment, were developed. 1) A water sample was aspirated through SEP-PAK C18 cartridge. Diphenyl ether herbicides were eluted with n-hexane and subjected to GC analysis. The recoveries of CNP, NIP and X-52 were 88.0-98.5%. 2) In the analysis of fish sample, SEP-PAK AgNO3-coated Florisil, prepared originally, was used for cleaning up instead of glass column packed with AgNO3-coated Florisil. Overall recoveries of diphenyl ether herbicides, CNP, NIP and X-52, in fortified samples were 88.0, 81.2 and 93.4%, respectively. Correlation coefficient between the levels of CNP in actual samples by the proposed method with SEP-PAK cartridge and by the other method by using glass column reported previously was 0.992. 3) In the case of river sediment, SEP-PAK Florisil was used to clean up instead of glass column packed with Florisil. Diphenyl ether herbicides in fortified materials were quantitatively detected. And all over recoveries with this cartridge were 94.5-98.4%. As a result, SEP-PAK cartridges were found to be very useful for their simplicity, rapidity, efficiency and reproducibility, as a pretreatment for the analysis of diphenyl ether herbicides in various samples.