抄録
Influence of pesticide and fertilizer on the ground water was investigated in vegetable field zone at Kakamigahara Heights located in the central Japan. Though organic bromine compounds have rarely been found in ground water, in this study, 1,2-dibromoethane derived from pesticide was found. Water samples from 9 locations in vegetable field zone were collected 12 times during 16 months, and 1,2-dibromoethane was always observed at 7 locations. Its mean value at each location ranged from 0.15 μg/1 to 0.28 μg/1. Though the pesticide containing 1,2-dibromoethane was used in the limited period, 2 weeks in a year, observed annual variation of 1,2-dibromoethane was small. Br- ion derived from decomposition of 1,2-dibromoethane raised Br/Cl ratio in the ground water and then, including sorrounding area, the locations where 1,2-dibromoethane was detected higher ratio as compared with those not detected. Of major components in the ground water, Ca2+, Mg2+, NO3-, and SO42- ions showed high concentations affected by fertilizer, but those annual variations were small, similar to that of 1,2-dibromoethane.
