Prenatal Exposure to the Herbicide 2,4-D Is Associated with Deficits in Auditory Processing During Infancy

Details

• Personal Author:
  Chen M ; Ji C ; Li M ; Lozoff B ; Meeker JD ; Shao J ; Silver MK ; Xia Y
• Description:
  INTRODUCTION: Despite widespread use, many herbicides and fungicides are not well studied for neurological effects. Fetal and infant brains are rapidly developing, yet the effects of early-life exposure to these classes of pesticides on visual and auditory function are unknown. Here we examined the effects of prenatal herbicide and fungicide exposure on infant grating visual acuity (VA) and auditory brainstem response (ABR). METHODS: 9 herbicides and 13 fungicides were measured in umbilical cord blood plasma from a cohort of infants in Fuyang County, China (n = 232). Grating VA and ABR latencies for waves I, III, V were measured at 3 time points: 6 weeks, 9 months, and 18 months. Outcomes included VA score, ABR wave V latency and ABR central conduction time (CCT wave V- wave I). Pesticides were analyzed as 3-level ordinal (non-detect ND/medium/high), or dichotomous (ND/detect), depending on detection rates. Linear mixed models were used to evaluate relations between pesticides and VA and ABR outcomes. RESULTS: 2,4-dichloroacetic acid (2,4-D), prometryn, simazine, and tetrahydrophthalimide (THPI, a metabolite of captan) were detected in 27%, 81%, 17%, and 16% of samples, respectively. Infants prenatally exposed to 2,4-D had slower auditory response times at 6 weeks. Infants with cord levels of 2,4-D > 1.17 ng/mL had wave V latencies that were 0.12 (95% CI: 0.03, 0.22) ms slower (p = 0.01) and overall CCTs that were 0.15 (95% CI:0.05, 0.25) ms slower (p = 0.003) than infants with non-detectable 2,4-D in their cord blood. No other statistically significant findings were observed for the other herbicides and fungicides or for the grating VA outcome. CONCLUSIONS: Prenatal exposure to the herbicide 2,4-D was associated with slower auditory signal transmission in early infancy. ABR latencies reflect auditory pathway maturation and longer latencies may indicate delayed auditory development. Description provided by NIOSH
• Subjects:
  • Environmental Exposure
  • Eye
  • Fungi
  • Fungicide, Industrial
  • Herbicides
  • Infant, Newborn
  • Occupational Health
  • Pregnancy
  • Risk Assessment
  • Risk Factors
  More +
• Keywords:
  • In utero exposure
  • Prenatal exposure
  • Pregnancy
  • Herbicides
  • Exposure levels
  • Risk factors
  • Auditory system
  • Children
  • Fungicides
  • Neurological system
  More +
• ISSN:
  0013-9351
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Michigan ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  486-494
• Volume:
  172
• NIOSHTIC Number:
  nn:20055277
• Citation:
  Environ Res 2019 May; 172:486-494
• Contact Point Address:
  John D. Meeker, Department of Environmental Health Sciences, University of Michigan, 1835 SPH I, 1415 Washington Heights, Ann Arbor, MI 48109, USA
• Email:
  meekerj@umich.edu
• CAS Registry Number:
  • (2,4-Dichlorophenoxy)acetic acid (CAS RN 94-75-7)
  • Captan (CAS RN 133-06-2)
  • Prometryn (CAS RN 7287-19-6)
  • Simazine (CAS RN 122-34-9)
  • Tetrahydrophthalimide (CAS RN 27813-21-4)
• Federal Fiscal Year:
  2019
• Performing Organization:
  University of Michigan, Ann Arbor
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Environmental Research
• End Date:
  20280630
• Download URL:
  https://stacks.cdc.gov/view/cdc/217618/cdc_217618_DS1.pdf
• File Type:
  [PDF - 1.25 MB]
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:fbca55390d850ac6fe357d4d5551de1443c0477c89f48d368dafb08c518ed1af43e76f8994ac11093bfb1d8d40bf9ac35a1a819d5b431d30912ccafe979e09e1