Author Interviews, Nature, OBGYNE, Pediatrics, Toxin Research / 05.09.2017
Adverse Birth Outcomes and Agricultural Pesticide Use in the San Joaquin Valley of California
MedicalResearch.com Interview with:
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Dr. Larsen[/caption]
Ashley Larsen, PhD
Assistant professor
Bren School of Environmental Science & Management
University of California, Santa Barbara
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The relationship between pesticides and adverse birth outcomes has been recognized as an important question for quite some time, and there have been many good studies on the topic. Since randomly exposing people to different levels of pesticides is clearly unethical, researchers focused on the health consequences of non-occupational pesticide exposure often have to choose between detailed studies that follow a couple hundred or couple thousand individuals through pregnancy or larger scale studies that use easier to observe, but less accurate metrics of pesticide exposure (e.g. nearby crops or crop types). Here we tried to provide complementary insight by bridging the gap between detail and scale using detailed pesticide use data and individual birth certificate records for hundreds of thousands of births in an agriculturally dominated region of California. While we found negative effects of pesticide use on birth outcomes including low birth weight, preterm birth and birth abnormalities, these effects were generally in the magnitude of a 5-9% increase in probability of an adverse outcome, and only observed for individuals exposed to very high levels of pesticides.
Dr. Larsen[/caption]
Ashley Larsen, PhD
Assistant professor
Bren School of Environmental Science & Management
University of California, Santa Barbara
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: The relationship between pesticides and adverse birth outcomes has been recognized as an important question for quite some time, and there have been many good studies on the topic. Since randomly exposing people to different levels of pesticides is clearly unethical, researchers focused on the health consequences of non-occupational pesticide exposure often have to choose between detailed studies that follow a couple hundred or couple thousand individuals through pregnancy or larger scale studies that use easier to observe, but less accurate metrics of pesticide exposure (e.g. nearby crops or crop types). Here we tried to provide complementary insight by bridging the gap between detail and scale using detailed pesticide use data and individual birth certificate records for hundreds of thousands of births in an agriculturally dominated region of California. While we found negative effects of pesticide use on birth outcomes including low birth weight, preterm birth and birth abnormalities, these effects were generally in the magnitude of a 5-9% increase in probability of an adverse outcome, and only observed for individuals exposed to very high levels of pesticides.
Dr. Leland McClure[/caption]
Leland McClure, PhD
Director in Medical Affairs for Quest Diagnostics
Fellow of the American Board of Forensic Toxicology
MedicalResearch.com: What is the background for this study?
Dr. McClure: Quest Diagnostics is the leading provider of diagnostic information services, providing clinical lab testing to about one in three American adults each year. As a result, we've amassed the largest private clinical laboratory database in the United States, based on 20 billion data points from lab testing. Quest uses this data (in de-identified, HIPAA compliant form) to perform research -- called Quest Diagnostics Health Trends(TM) -- to reveal insights on important health issues to inform clinical patient management and health policy. Other Health Trends reports have focused on diabetes, pregnancy and influenza, among others.
Prof. Claire Roberts[/caption]
Professor Claire Roberts PhD
Robinson Research Institute
Adelaide University
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Roberts: Our research aimed to identify novel risk factors for the four main complications of pregnancy;
Dr. Lori Hoepner[/caption]
Lori A. Hoepner, DrPH
Department of Environmental Health Sciences
Columbia University
New York, NY 10032
MedicalResearch.com: What is the background for this study?
Dr. Hoepner: The Columbia Center for Children’s Environmental Health was funded starting in 1998. Pregnant African American and Dominican mothers residing in Northern Manhattan and the South Bronx were enrolled from 1998 to 2006, and mothers and their children have been followed since this time. We collected urine samples from the pregnant mothers in their third trimester and from the children at ages 3 and 5. At ages 5 and 7 we measured the height and weight of the children, and at age 7 we also measured body fat and waist circumference.
MedicalResearch.com: What are the main findings?
Dr. Hoepner: We found a significant association between increased prenatal exposure to Bisphenol A (BPA) and increases in childhood body fat measures of waist circumference and percent body fat at age 7. Our research builds on earlier findings of an association between prenatal exposure to BPA and body fat in children up to age 4, and this is the first study to report an association at age 7.
Dr. Debra Silverman[/caption]
Dr. Debra Silverman Sc.D
Branch Chief and Senior Investigator in the Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology & Genetics
National Cancer Institute
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Silverman: We know that bladder cancer mortality rates have been elevated in northern New England for at least five decades. Incidence patterns in Maine, New Hampshire and Vermont are similar—about 20% higher than those for the United States overall. Elevated rates have been observed in both men and women, suggesting the role of a shared environmental etiologic factor.
A unique feature of northern New England is that a high proportion of the population uses private wells as their primary source of drinking water. The well water may contain low-to-moderate levels of arsenic. There are two possible sources of this arsenic contamination:
Dr. Steven Hicks[/caption]
Steven Daniel Hicks, M.D., Ph.D.
Penn State Hershey Medical Group Hope Drive, Pediatrics
Hershey, PA 17033
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Hicks: This research was inspired by results of the CHARGE study (examining environmental influences on autism) which showed that specific pesticides (including pyrethroids) increased the risk of autism and developmental delay, particularly when mothers were exposed in the 3rdtrimester.
We recognized that the department of health sprayed pyrethroids from airplanes in a specific area near our regional medical center every summer to combat mosquito borne illnesses. We asked whether children from those areas had increased rates of autism and developmental delay. We found that they were about 25% more likely to be diagnosed with a developmental disorder at our medical center than children from control regions without aerial spraying of pyrethroids.
