Toxicokinetics of Imidacloprid-Coated Wheat Seeds in Japanese Quail ( Coturnix japonica) and an Evaluation of Hazard.
Environ Sci Technol
; 53(7): 3888-3897, 2019 04 02.
Article
em En
| MEDLINE
| ID: mdl-30802040
Birds are potentially exposed to neonicotinoid insecticides by ingestion of coated seeds during crop planting. Adult male Japanese quail were orally dosed with wheat seeds coated with an imidacloprid (IMI) formulation at either 0.9 or 2.7 mg/kg body weight (BW) (â¼3 and 9% of IMI LD50 for Japanese quail, respectively) for 1 or 10 days. Quail were euthanized between 1 and 24 h postexposure to assess toxicokinetics. Analysis revealed rapid absorption (1 h) into blood and distribution to the brain, muscle, kidney, and liver. Clearance to below detection limits occurred at both dose levels and exposure durations in all tissues within 24 h. Metabolism was extensive, with 5-OH-IMI and IMI-olefin detected at greater concentrations than IMI in tissues and fecal samples. There was no lethality or overt signs of toxicity at either dose level. Furthermore, no evidence of enhanced expression of mRNA genes associated with hepatic xenobiotic metabolism, oxidative DNA damage, or alterations in concentrations of corticosterone and thyroid hormones was observed. Application of the toxicokinetic data was used to predict IMI residue levels in the liver with reasonable results for some field exposure and avian mortality events. It would appear that some affected species of birds are either consuming larger quantities of seeds or exhibit differences in ADME or sensitivity than predicted by read-across from these data.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Triticum
/
Coturnix
Limite:
Animals
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article