Monitoring of 15 pesticides in rainwater in Utsunomiya, eastern Japan, 1999-2000

• Published in: Journal of Pesticide Science Vol. 28; no. 1; pp. 1 - 7
• Main Authors: Suzuki, S. (Tochigi-ken. Agricultural Experiment Station, Utsunomiya (Japan)), Otani, T, Iwasaki, S, Ito, K, Omura, H, Tanaka, Y
• Format: Journal Article
• Language: English
• Published: Tokyo Pesticide Science Society of Japan 01.01.2003
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; JAPAN; MONITORING; PESTICIDAL PROPERTIES; PESTICIDES; RAIN; RESIDUES; Japan, Utsunomiya; formulation; shipment amount; spatial variation in deposited amount; pesticide residues in rainwater; Henry's law constant
• ISSN: 0385-1559; 1348-589X; 1349-0923
• DOI: 10.1584/jpestics.28.1

Residues of 15 pesticides in rainwater were investigated monthly from July 1999 to July 2000 at five sampling sites in Utsunomiya, eastern Japan. Additionally, the residues for each precipitation were measured at one site. Among pesticides applied mostly as granular formulations to paddy fields, simetryn, pretilachlor, mefenacet and iprobenfos with small Henry's law constants were infrequently detected. In contrast, the herbicides thiobencarb and esprocarb with large Henry's law constants were frequently detected outside of the application periods, suggesting that the volatilization from water and soil surfaces had continued for a long time. The annual (July 1999-June 2000) deposited amount as an average value among the sampling sites was largest for fenitrothion at 546 mu g/m sub(2), followed by thiobencarb at 196 mu g/m sub(2), esprocarb at 109 mu g/m sub(2), and fenobucarb, diazinon and phthalide at about 40 mu g/m sub(2) each. The relative standard deviations of the deposited amounts among the sampling sites were 30% or less. Fenitrothion, fenobucarb and phthalide were applied mostly as wettable powder, emulsifiable concentrate and dust formulations, allowing the pesticides to easily enter the atmosphere during the spraying or dusting process. The less variable distribution of these three pesticides is ascribable in part to the application of the above three formulations in large quantities. The annual deposited amounts of the other pesticides were about 20 mu g/m sub(2) or less, with marked variation among the sampling sites.