Pyrethroids: a new threat to marine mammals?
The present study constitutes the first investigation to demonstrate pyrethroid bioaccumulation in marine mammals, despite the assumption that these insecticides are converted to non-toxic metabolites by hydrolysis in mammals. Twelve pyrethroids were determined in liver samples from 23 male franciscana dolphins from Brazil. The median concentration values for total pyrethroids were 7.04 and 68.4 ng/g lw in adults and calves, respectively. Permethrin was the predominant compound, contributing for 55% of the total pyrethroids. Results showed a distinct metabolic balance of pyrethroids through dolphin life. High loads are received at the beginning of their lives and, when they reach sexual maturity, these mammals seem to degrade/metabolize pyrethroids. Maternal transfer of these compounds was also evaluated through the analysis of breast milk and placenta samples. Pyrethroids were detected in both matrices, with values between 2.53-4.77 ng/g lw and 331-1812 ng/g lw, respectively. Therefore, for the first time, a study shows mother-to-calf transfer of pyrethroids by both gestational and lactation pathways in dolphins.
Radioisotope Laboratory Eduardo Penna Franca-LREPF, Biophysics Institute Carlos Chagas Filho-IBCCF, Federal University of Rio de Janeiro-UFRJ, Brazil.
Mariana B
MB
Alonso
Maria Luisa
ML
Feo
Cayo
C
Corcellas
Lara G
LG
Vidal
Carolina P
CP
Bertozzi
Juliana
J
Marigo
Eduardo R
ER
Secchi
Manuela
M
Bassoi
Alexandre F
AF
Azevedo
Paulo R
PR
Dorneles
João Paulo M
JP
Torres
José
J
Lailson-Brito
Olaf
O
Malm
Ethel
E
Eljarrat
Damià
D
Barceló
D000818:Animals; D001938:Brazil; D004289:Dolphins / Q000378:metabolism; D004784:Environmental Monitoring; D005260:Female; D007306:Insecticides / Q000378:metabolism* / Q000633:toxicity; D008297:Male; D008895:Milk, Human / Q000378:metabolism; D011247:Pregnancy; D011722:Pyrethrins / Q000378:metabolism* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000378:metabolism* / Q000633:toxicity
D007306:Insecticides; D011722:Pyrethrins; D014874:Water Pollutants, Chemical