How Much Pesticide is on My Plate?

Transcription

1 How Much Pesticide is on My Plate? Dr. Jeff Miller 1

2 The Dirty Dozen, from the Environmental Working Group Dirty Dozen PLUS 51 produce items Potatoes = #12 Beginning Statements 1. We have an emotional attachment to food. 2

3 Beginning Statements 2. Very few people love pesticides. I Pesticides Beginning Statements 3. The internet is full of bad information. Scientific info abounds Everyone has a voice People can say whatever they want Little or no review process Search engines don t search everything on the net Have you heard of the Pacific Northwest Tree Octopus? 3

4 Questionable Online/TV Advice Beginning Statements 1. We have an emotional attachment to food. 2. Nobody loves pesticides. 3. The internet is full of bad information. 4. Risk is inherent with almost everything. We are more willing to accept risk when we understand the benefit. 4

5 What is the true risk of pesticides in our food? 5

6 Food Quality Protection Act (FQPA) Focus on protecting human health, environment. Reasonable certainty of no harm Increased scrutiny of effects on children (10x safety factor). Consider aggregate risk from multiple sources. Registration review every 15 years. Setting Risk Tolerances Under FQPA Residue Tolerances Risk Exposure Pre-FQPA Post-FQPA Adapted from FQPA: The Food Quality Protection Act, NC State University, AG-609 6

7 FQPA Product Reregistration Status Re-registered 5,121 Amended 3,491 Canceled 11,702 Suspended 40 Total products completed 20,354 Products pending action 4,621 Data as of FY2016 How is toxicity measured? Animal, human, environmental studies Exposure Chronic vs acute Dose = concentration x time LD 50 mg/kg, ppm Dermal and oral exposure LC 50 mg/l, ppm, mg/m 3 Inhalation 7

8 EPA Tolerance for Pesticides NOAEL = No Observable Adverse Effect Level ADI = Acceptable Daily Intake Lowest NOAEL of most sensitive test ADI often = NOAEL divided by safety factor (100 or 1000) Includes all circumstances of dietary exposure EPA assumes highest label usage ADI NOAEL 8

9 Pesticide Labels When used according to the label, pesticides will not cause unreasonable harm to the environment. The label is the law as to how a product can be used. ADI NOAEL Product use according to label 9

10 USDA-ARS Pesticide Data Program Established in 1991 Focuses on children s food Not designed for enforce EPA pesticide tolerances Data collected from ~600 sites Test for 450 pesticides, breakdown products ~10,000 samples collected/year 2015 Samples Fresh and processed fruits and vegetables Grains Dairy Meat and poultry Honey Corn syrup Infant formula Fish Nuts Peanut butter Summary of Pesticide Data Program Samples 11,893 10,104 10,619 10,187 % No Detections * 15 % Below Tolerance >99 >99 >99 >99 % Above Tolerance % W/O Tolerance * 3.9 *Could not access data. 10

11 PDP 2015 Chlorothalonil # Samples # (%) Detections Detected Values (ppm) EPA Tolerance (ppm) Apples NT Cucumbers (22) Grapefruit 90 0 NT Nectarines Oranges* (0.1) NT Peaches (0.3) Strawberries* (0.1) NT Watermelon Total 3, *Two detections where no tolerance existed. Of those with tolerance, none exceeded that value. Where do non-tolerance residues come from? Spray drift Planting of crops in field with previous pesticide use Post-harvest transfer of pesticide residue in storage 11

12 PDP 2015 Potato Residues Active Ingredient # Detects % Detects Lowest Detect (ppm) Highest Detect (ppm) EPA Tolerance Azoxystrobin Chlorpropham Clothianidin Difenoconazole Fludioxonil Imidacloprid Metlaxyl/Mefenoxam Pentachloroaniline Thiabendazole Thiamethoxam total samples. None exceeded tolerance. Detection of Pesticides 1950 = 1 ppm 1965 = ppm (1 ppb) 1975 = ppm (1 ppt) 2005 = ppm (1 ppq) ppm = 1 ml/l or 1 mg/kg 1 inch in 16 miles 1 second in 11.5 days 1 minute in two years ppb = 1 µl/l or 1 µg/kg 1 second in 32 years 1 sheet of toilet paper in a roll stretching from New York to London 1 silver dollar in a roll stretching from Detroit to Salt Lake City 1 drop of water in an Olympic size swimming pool 12

13 These data only relate to the presence of pesticide residue, NOT amount. The assumption is that any pesticide residue is bad. All substances are poisons; there is none which is not a poison. The right dose differentiates poison from remedy. - Paracelsus Taken from Casarett & Doull s Toxicology: The Basic Science of Poisons. 13

14 How much do I have to eat to get sick? Max PDP Residue NOAEL Dose Servings equivalent to NOAEL Commodity EWG Rank Residue (ppm) (mg/kg-bw/day) Child Teen Woman Man Apple 4 Diphenylamine ,190 Celery 9 Dicloran ,843 15,686 19,608 27,451 Cucumbers 13 Oxamyl oxime Peach 5 Iprodione ,890 3,779 4,724 6,614 Potato 12 Chlorpropham ,469 2,938 3,672 5,141 Strawberries 1 Captan Sweet bell peppers 11 Acephate = ( ) h 1000 ( ) From R. Krieger, UC Riverside Perspective on Pesticide Residues in Fruits and Vegetables 14

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16 Environmental Working Group Revisited 79% of Society of Toxicology say EWG overstates risks. Website claims one strawberry sample had 20 residues. It was from Mexico. 16

17 Toxicity Values of Common Products Pesticide LD50 (ppm) Product LD50 (ppm) Aldicarb 0.8 Capsaicin 47 Diazinon 300 Caffeine 200 Ethylene glycol 460 Ridomil Gold SL 550 Benadryl 500 Flonase 1000 Malathion 1000 Acetylsalicylic acid 1000 Atrazine 1780 Phosphorous acid >5000 Amoxycillin 2870 Sodium chloride 3320 Accutane 4000 Always follow the label! Use pesticides responsibly. So what do I do now? Speak up in defense of agriculture. 17

18 African Proverb Well fed people have many problems, hungry people have just one. 18