Effects of Pesticide Exposure on Learning and Development

Transcription

1 Effects of Exposure on Learning and Development Patricia Moulton, Ph.D., Thomas Petros, Ph.D., Sally Pyle, Ph.D., Ric Ferraro, Ph.D., Patrick Kerr, M.A., Sue Offutt, Ph.D. & Dana Barr, Ph.D. Regional Children s Environmental Health Summit Vail, Colorado September 19, 2006 Funding for this study provided by the National Institute of Environmental and Health Sciences. Research Team UND Faculty CDC Laboratory Phlebotomists Thomas Petros Dana Barr Sandie Antonson Patricia Moulton Charles Dodson Kristi Grove Ric Ferraro Ralph Whitehead Tara Johnso Sally Pyle Dawn Korynta Sue Offutt Naomi Sterf Steve Hawthorne Tara Waldal Ruth Paur Graduate Students Undergraduate Students Holly Dannewitz Cassandra Lee Matt Garlinghouse Silje Lynne Shyla Muse Ashley Olson Matthew Myrvik Bethany Reuter Anna Marie Carlson Christine Wegner Jason Douglas Catherine Woell Patrick Kerr Karyn Plumm Kristi Sather Caitlin Schultz Jen Short 1

2 What are s? Herbicides Insecticides Rodenticides Fungicides Exposure and Children 2

3 Exposure and Cognitive Ability in Children Objectives of Current Study Objective 1 Examine the impact of chronic routine exposure to pesticides on cognitive and motor performance in children between 7 and 12 years of age, including memory performance, executive function performance, motor performance, and performance on school-related achievement tests. Objective 2 Measure the concentration of several pesticides and cholinesterase in the blood or urine in children between 7 and 12 years of age and examine associations between pesticide and cholinesterase concentration and cognitive and motor performance. 3

4 Red River Valley s in North Dakota 4

5 Participants Group= 64 children and their parents living on or next to an active farm or field Group= 68 Children and their parents living at least one mile from an active farm or field Measurements- Children Physiological Height and Weight Blood and Urine- pesticides, cholinesterase, trace minerals Motor Grooved Pegboard Test Benton Visual Retention Test Finger Tapping Test Hand-eye Coordination Test Cognitive Wechsler Intelligence Scale for Children-IV California Verbal Learning Test Children Verbal Fluency Test Continuous Performance Test Wisconsin Card Sorting Test Wechsler Individual Achievement Test- 2 nd ed- Reading & Listening Comprehension 5

6 Measurements- Parents Cognitive Behavioral Wechsler Adult Intelligence Scale-III Child Behavior Checklist Vocabulary & Block Design ADHD Rating Scale-IV Nutritional Status NIH Diet History Questionnaire Food Security module 24-Hour Dietary Recall Developmental Tanner Pubertal Development Test Developmental Milestones Environmental use and exposure questionnaire Surveys on family and child medical history, sleep, occupation, income, education level Measurements- Teachers Behavioral Teacher Report Form for Child Behavior Checklist Teacher Report Form for ADHD Rating Scale-IV 6

7 Intelligence Test Results Child Demographics Average Age Grade 7

8 Child Full-Scale IQ* Male Female Male Female Verbal Comprehension Index** Male Female Male Female 8

9 Verbal Comprehension Subtests Male Female Male Female Similarities** 9.82 (2.60) 9.36 (3.03) (3.21) (4.12) Vocabulary* (2.77) 9.16 (2.69) (2.92) (3.43) Comprehension* 9.87 (2.53) 9.72 (2.69) (2.68) (3.77) Perceptual Reasoning Index/* Male Female Male Female 9

10 Perceptual Reasoning Subtests Male Female Male Female Block Design* (2.37) 9.88 (2.93) (2.77) (2.75) Picture Concepts (2.61) (3.14) (2.63) (2.49) Matrix Reasoning (2.49) (3.03) (2.54) (2.68) Working Memory Index Male Female Male Female 10

11 Working Memory Subtests Male Female Male Female Digit Span 9.77 (2.47) 9.48 (2.60) 9.57 (2.83) 9.85 (2.67) Letter- Number Sequencing 9.79 (2.69) (2.81) (3.04) (2.29) Processing Speed Index** Male Female Male Female 11

12 Processing Speed Subtests Male Female Male Female Coding** 7.85 (2.10) 9.52 (2.42) 8.03 (2.61) 9.45 (2.89) Symbol Search* 9.10 (2.85) (3.01) (2.48) (2.02) Parents Estimated Full Scale IQ Estimated FSIQ DuncanSES HollingsheadSES 12

13 Biological Measurements Cholinesterase Concentrations (Ache) U/ml Male Female Male Female 13

14 Cholinesterase Concentrations (Pche) U/ml Male Female Male Female Acute Analysis (Herbicides) Atrazine Acetochlor Metolachlor** ,4-D 2,4,5-T ng/ml 14

15 Acute Analysis (Other) 0.36 Pyrethroids* Deet** ng/ml Acute Analysis (Organophosphates) Isazaphos Coumaphos Pirmiphos methyl Diazinon Malathion Parathion Chloropyrifos

16 Persistent (Organochlorines) Dieldrin* Hexaclorobenzene Hepatpchlor Mirex Oxychlordane Chlordane Persistent s (Lindane) Betahexachlorocyclohexane* Gammahexachlorocyclohexane ng/g 16

17 Persistent s (DDT) PP DDT DDE OP DDT ng/g Conclusions A significantly lower IQ was found in children living in areas of a great amount of pesticide use. Although, both groups were within the average range on IQ. This difference was independent of parents IQ and their socio-economic status. There is evidence of exposure to pesticides based on biological measurements. However, both groups were found to have been exposed to a number of pesticides. Next step is to run a multiple regression to examine the association between the biological measurements of pesticides and the IQ results along with the other cognitive tasks. 17

18 Significant Cholinesterase Ache Pche Negative Comp Positive PSI Sym Significant Herbicide/Other Atrazine Acetochlor Metolachlor 2,4-D 2,4,5-T Pyrethroids Deet Negative VCI, Sim, Voc Sim Positive BD Symb 18

19 Significant Organophosphate Isazaphos Coumaphos Pirmiphos methyl Diazinon Malathion Parathion Chloropyrifos Negative Voc Positive PRI, BD Significant Organochlorine Dieldrin Hexaclorobenzene Hepatochlor Mirex Oxychlordane Chlordane Negative WMI Positive BD MR BD 19

20 Significant Lindane & DDT Betahexachlorocyclohexane Gammahexachlorocyclohexane PP DDT DDE Negative Voc PRI, PC, MR Positive OP DDT Limitations and Future Directions The measurement of pesticide exposure is complex due to the large number of potential pesticides to measure and the number of variations in exposure. Future studies are needed to further explore the association between particular groups of pesticides and IQ and to examine the longitudinal effects of pesticide exposure. 20

21 For more information contact: Patricia Moulton, Ph.D. Thomas Petros, Ph.D. 21