農藥溶劑更換對哺乳動物口服急毒性差異之評估

Safety evaluation in rats of alternative solvents for pesticides formulated with emulsifiable concentrate

蔡孟君(Tsai, M. C.) ； 黃振聲(Hwang, J. S.) ； 陳家鐘(Chen, C. C.) ； 王順成(Wang, S. C.) ； 廖俊旺(Liao, J. W.)

《植物保護學會會刊》 46卷3期 (2004/09) Pp. 267-280

https://doi.org/10.6715/PPB.200409_46(3).0006

摘要

乳劑農藥成品常含有溶劑作為載體，大部份溶劑具有低閃火點，在製造儲存及運送過程中易起火燃燒，同時具揮發性，容易造成急性中毒。為探討農藥二甲苯（xylene）溶劑更換其他有機溶劑後，對哺乳動物口服急毒性之差異，選擇已知口服急毒性較低之殺蟲劑，分別以xylene及Solvesso-100（S-100）為溶劑，配製成賽滅寧（cypermethrin）5 % EC、百滅寧（permethrin）10 % EC、芬化利（fenvalerate） 20 % EC及陶斯松（chlorpyrifos）40.8 % EC等四種乳劑，比較溶劑不同之乳劑對大鼠口服急毒性影響。結果顯示，xylene及S-100溶劑經餵飼大鼠後，造成俯臥不動、 抽搐、遲鈍、活動力減少等中毒症狀及死亡，並測得xylene及S-100溶劑對大鼠口服急毒性LD_(50)值，分別為4,945及3,670 mg/kg。依據液體藥劑之口服急毒性等級，xylene及S-100溶劑對大鼠口服急毒性均大於2,000 mg/kg，屬於「輕毒性（slightly hazardous）」等級；而單一溶劑之S-100口服急毒性則比xylene稍強。另比較農藥乳劑含xylene（X）及S-100（S）二種溶劑對大鼠口服急毒性，賽滅寧5 % EC之LD50值分別為＞ 5,329（X）及3,678 mg/kg（S）；百滅寧10 % EC分別為＞5,000（X）及5,454 mg/kg（S）；芬化利20 % EC分別為4,016（X）及3,944 mg/kg（S），均屬於「輕毒性」等級；陶斯松40.8 % EC之LD_(50)值分別為306（X）及280 mg/kg（S），屬於「中等毒性（moderately hazardous）」等級。以上結果顯示，除賽滅寧成品（S）及陶斯松40.8 % EC（X & S）之LD_(50)值與原文獻資料值稍強外，其餘乳劑之LD_(50)值雖稍有差異，但毒性等級分類並無增強。又以S-100配製之百滅寧10 % EC、賽滅寧5 % EC及芬化利20 % EC對大鼠之口服急毒性比xylene乳劑稍強，但毒性等級均相近。由於Solvesso系列溶劑具有理化性及安定性較佳，並且在對動物毒性未增強前題下，可作為農藥乳劑載體較佳選擇之一。

關鍵字

農藥乳劑 ； 二甲苯 ； Solvesso ； 口服急毒性 ； 大鼠

並列摘要

Emulsifiable concentrate (EC) pesticides comprise one of the general formulations for pesticides. However, the lower flash point of solvents may cause it to ignite during processing, storage, and transportation. Potential symptoms of acute overexposure are sometimes found in farmers and workers. The objective of this study was to evaluate the acute oral toxicity (oral LD_(50)) in Sprague-Dawley (SD) rats of pesticides formulated with xylene and Solvesso-100 emulsifiable concentrate. Insecticides, including 5 % cypermethrin, 10 % permethrin, 20 % fenvalerate, and 40.8 % chlorpyrifos, with lower acute oral toxicities, were chosen and formulated using xylene or S-100. For assessment of acute oral toxicity, SD rats were gavaged by gastric tube with different doses of EC-formulated pesticides. Results indicated that the LD_(50) values of xylene (X) and S-100 (S) were 4945 and 3670 mg/kg, respectively. Both of these two solvents are classified as slightly hazardous. The LD_(50) value of S-100 was lower than that of xylene. The LD50 values of 5 % EC cypermethrin, 10 % permethrin, 20 % EC fenvalerate, and 40.8 % EC chlorpyrifos formulated with xylene (X) and S-100 (S) were 5329 (X) and 3678 mg/kg (S), ＞ 5000 (X) and 5454 mg/kg (S), 4016 (X) and 3944 mg/kg (S), and 306 (X) and 280 mg/kg (S), respectively. Generally, the oral LD50 values of S-100-formulated pesticides showed a slight decrease compared with the xylene-formulated pesticides. However, the S-100-formulated pesticides did not exhibit significant enhancement of toxic effects in rats. The Solvesso solvent is more stable and may be a good substitute for xylene in EC-formulated pesticides.

並列關鍵字

emulsifiable concentrate pesticides ； xylene ； Solvesso ； acute oral toxicity ； rats