Exposure to pyrethroid insecticides among pregnant women and their child in Rio de Janeiro City - Results from a birth cohort (PIPA Project)

Abstract

Background/aims: Pyrethroid insecticides are largely used in Brazil, one of the world's largest consumers of pesticides. We investigated the exposure of pregnant women and their child at the time of birth and 3rd month of life to pyrethroids and its association with sociodemographic variables, self-reported diseases, and childbirth outcomes in the City of Rio de Janeiro. Few studies investigate levels of pyrethroid in neonates.Methods: We performed a cross-sectional analysis of data from Rio birth cohort (PIPA study). Pregnant women at 3rd trimester who received antenatal care at the Federal University of Rio de Janeiro’s Maternity School. Mother’s sociodemographic, daily habits, existing disease and some birth outcomes about child was collected. Mother's (n=138), newborn's (n=29) and 3-month old child's (n=46) urine samples was analyzed for detection of pyrethroid metabolites 3-PBA and 4-FPBA using liquid chromatography coupled to mass spectrometry. We did a descriptive analysis of the excretion profile of pyrethroids from mothers and their children.Results: From all samples, 70% of woman, 28% of newborns, 30% of 3 months old children showed urinary concentrations of pyrethroid metabolites. Pyrethroid metabolites geometric mean (GM) was 0,78 ng mg-1 for mothers, 0,16 ng mg-1 for newborns and 0,89 ng mg-1 at 3rd month old. Mother’s pyrethroid levels doesn’t seem to have relationship with child’s pyrethroid levels at follow up. Pregnant women with diabetes excreted higher levels of pyrethroids in the urine (p<0,01); newborns small for gestational age (SGA) excreted higher levels of pyrethroids in the urine (p=0,01); similarly, cephalic perimeter and Apgar was associated with pyrethroid exposure in 3rd month old babies (p=0,02; p=0,02).Conclusions: Newborns (28%) presented pyrethroids metabolites in urine even at birth. Pyrethroid exposure appears to be related with diabetes in mothers, withsize for gestational age in newborns and with cephalic perimeter and Apgar in 3 months old child.