Pyrethroid residues in milk and blood of dairy cows following single topical applications

The presence of the pyrethroid insecticides flumethrin, deltamethrin, cypermethrin and cyhalothrin in milk and blood of 10 cows was determined after single dermal applications of recommended doses. Milk and blood samples were collected every 7 days over a 35 d period and analyzed by high performance liquid chromatography. The highest residues in milk were found on day 28 for flumethrin and day 1 for deltamethrin, cypermethrin and cyhalothrin, while in blood the highest concentrations were present on day 28 for flumethrin and deltamethrin, the first day for cypermethrin, and day 14 for cyhalothrin.

HPLC determination of flumethrin, deltamethrin, cypermethrin, and cyhalothrin residues in the milk and blood of lactating dairy cows

A procedure to determine residue concentrations of synthetic pyrethroid insecticides (flumethrin, deltamethrin, cypermethrin and cyhalothrin) in the milk and blood of lactating dairy cows was developed. Extraction was performed with acetonitrile, n-hexane partitioning, and silica gel column cleanup with n-hexane and diethyl ether. Analysis was carried out by high- performance liquid chromatography and ultraviolet detection. Recovery of the four pyrethroids averaged 78 to 91% with a minimum detectable concentration of 0.001 mg/kg. The method was reproducible and sensitive.

Estudo de possíveis correlações entre miastenia grave e exposiçao crônica a pesticidas em nosso meio

Pós-graduação em Bases Gerais da Cirurgia - FMB