Residues and fate of endosulfan on field-grown pepper and tomato

✍ Scribed by Antonious, George F.; Byers, Matthew E.; Snyder, John C.

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 234 KB
• Volume: 54
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1096-9063(199809)54:1<61::aid-ps780>3.0.co;2-m

✦ Synopsis

Endosulfan (Thiodan 3 EC), a mixture of aand b-isomers, was sprayed on 92-day-old Ðeld-grown pepper and tomato at the recommended rate of 0É61 kg AI ha~1. Plant tissue samples were collected at 1 h to 14 days after application and analysed to determine the content and dissipation rate of endosulfan isomers (a-and b-endosulfan) and the major metabolite, endosulfan sulfate. Analysis of samples was accomplished using gas chromatography-mass selective detection (GC-MSD). The results indicated the formation of endosulfan sulfate as a residue component on the plant tissues and also the relatively higher persistence of the b-isomer as compared to the a-isomer on pepper fruits. The initial total residues (a-and b-endosulfan isomers plus endosulfan sulfate) were higher on leaves than on fruits. On pepper fruits, the a-isomer, which is the more toxic to mammals, dissipated faster than the less toxic b-isomer. Total residues (a-and b-endosulfan isomers plus the sulfate metabolite) on tomato leaves revealed longer persistence 4É6 days) compared to the total residues detected (t 1@2 on pepper leaves 2É0 days) 3È14 days following spraying. Persistence of the (t 1@2 b-isomer on pepper fruits was high 3È14 days following spraying compared to on tomato fruits. This long persistence increases risk of exposure of the consumer. In addition, the longer persistence of the total residues on tomato foliage should be considered of importance for timing the safe entry of tomato harvesters due to the high mammalian toxicity of endosulfan.

1998 Society of Chemical ( Industry