Stabilization of the avicide 3-chloro-p-toluidine as the beta-cyclodextrin adduct

Stabilization of the avicide 3-chloro-p-toluidine (CPTH) on rice baits by pseudo latex polymeric coating and beta-cyclodextin inclusion was investigated. When CPTH-treated rice baits were exposed to sunlight, the CPTH formed colored compounds, which exacerbated problems with bait acceptance and efficacy. Fluidized bed coating with controlled-release polymeric psuedo latexes (RS, RL, NE) reduced CPTH loss but did not eliminate color formation. Enteric pseudo latex coatings (CAP and 4110) gave mixed results. Coating 4110 reduced CPTH loss but still allowed color formation, whereas CAP allowed more CPTH loss than any other coating as well as increased color formation. Inclusion in beta-cyclodextrin (molar ratio 1:1) led to enhanced retention of CPTH and minimal color formation. The CPT/beta-cyclodextrin adduct increased retention of CPTH from 43 to 70% upon simulated weathering. The retention was independent of the adhesives used for attachment.