Five-Year Soil Concentrations of Seven Termiticides in Two Mississippi Soil Types

Abstract

Two Mississippi soil types were treated with seven termiticides representing six active ingredients. Soil locations and types were Gulfport, MS (Poarch fine sandy loam) and Mississippi State University (Faulkner silt loam). Active ingredients used in the study are cypermethrin-D, permethrin-Dr, chlorpyrifos, isofenphos, fenvalerate, cypermethrin-Pr, and bifenthrin. The lowest registered label concentration was used for the treatments. Treatments were applied to the outside and inside walls of test foundations. Test foundations were covered after treatment to provide a simulated crawl space area and the areas were sampled independently of each other. Treated soils were sampled on day of treatment and at 3, 6, 9, 12, 18, 24, 36, 48, and 60 months post treatment, with the exception of isofenphos. This treatment was not sampled at 24 and 36 months. Soil samples were extracted with acetone and analyzed by gas liquid chromatography. Initial soil residue concentrations for all products were high and related to the dilution rate at which the compounds were mixed. Dilutions varied from a low of 0.06% (bifenthrin) to a high of 1.0% (chlorpyrifos). The products showed a gradual decline over time, with the exception of isofenphos. Most of the isofenphos degraded within the first 9 months.