1. Critical thinking in food safety
                                                   
Critical thinking in food safety
Thomas J. Montville

2. This lecture will help you …
gain confidence in “sorting out the numbers.”
sort and evaluate claims and counter claims.
help you be a defacto spokesperson (for something).
Montville, IFT 2004

3. You will be (are) a defacto spokesperson – FS/Nutrition
Food companies are filling our food with cancer causing poisons.
Food is cheap because all large food companies are getting huge government subsidies.
Natural food is healthier and more nutritious than food made by Agribuisness.
etc., etc.
Montville, IFT 2004

4. You will be (are) a de facto spokesperson – FS/Nutrition
Food companies are filling our food with cancer causing poisons.
Food is cheap because all large food companies are getting huge government subsidies.
Natural food is healthier and more nutritious than food made by Agribuisness.
etc., etc. ?

5. What’s the harm in misrepresent in facts?
False sense of security- can cause bigger problems
Bigger risks ignored – or incurred.
We drink bottled water due to worries about municipal water (pesticides, cancer, heavy metals).
But bottled has few standards,
Wastes water in manufacturing
May have BPA.
Bigger problems than water; obesity. Focuses on food, rather than exercise.
Increased costs
Unnecessary, and Ineffective Testing (McDonalds)
Organic food costs 67% more
Environmental damage of packaging vs. additives
Biotech foods – cheaper (at least on the surface), may be better for the environment. (Nuclear power vs coal)

6. Are we spending enough on food safety?
How much are we spending?
USDA $797 million
FDA $ 90 million
Industry $ 90 million**
Total $997~ 1,000 million
What’s the first two things you should as about these numbers?
Google Guess
Montville, IFT 2004

7. Are we spending enough on food safety?
Total spent $997~ 1,000 million
Basis of comparison
Population of U.S. (300 million) $ 3 per person
# Illness (76 million) ~ $ 12 per illness
# Death (5,000) ~ $ 20 per death
$ Value of Food Industry $ 3.2 trillion
109/1012 = x/ % of food dollars
Is this enough?
Google Guess
Montville, IFT 2004

8. Regulations result from
“the facts” derived from “the best science available”
economics
practicality
compromise
politics
Montville, IFT 2004

9. The problem with “facts”….
fact can be very dull (Inconvenient Truth)
facts require interpretation
Try to get at the data underneath “the facts”.
Beware of statistics – try to get at the underlying numbers
*Beware of ratios:
The increased use of food additives, has caused the % of childhood deaths caused by cancer has increased steadily over the last 100 years.
*Beware of % and “fold.”
The data: Incidence of cancer increased from 1 in 1,000,000 to 2 in 1,000,000.
The buzz: 2-fold increase in cancer. Cancer up 100%.

10. Look for the grain of truth. Take it with a grain of salt.
Montville, IFT 2004

11. Therefore % due to cancer .
Stats based on ratios can change because of numerator (top) or denominator (bottom).
Examine % of children dying of cancer. Absolute number (cases/100,000 deaths) Infectious disease , infant mortality , industrial accidents , malnutrition 
Absolute number (cases/100,000 deaths) of cancer cases remains unchanged.
Therefore % due to cancer .
Montville, IFT 2004

12. An important digression on “number literacy”
One can’t explain what one doesn’t understand.
Montville, IFT 2004

13. Think through the premise Homework #1
In Defense of Food, Michael Pollon stated that the average American consumes 300 more calories per day than they did in 1980.
Is this credible?
(3,500 calories = 1 pound)
Montville, IFT 2004

14. Think through the premise Homework #2
It has been stated* that the American diet is so bad that the average American has gained 10 pounds since *Do not link this to the previous example.
Is the weight gain a credible number?
Does it constitute a real problem?
How many excess calories per day would it take to cause this weight gain?
Is there a non-dietary solution to this problem?
Montville, IFT 2004

15. Homework # 3, a premise that looks good on the surface.
In Defense of Food, Michael Pollon suggests that many of our problems due to the low cost of food. The US pay 10% of income on food while the French and Italians pay 15%. We’d be healthier if we increased the amount we paid for food by 50%.
What do you think of this? Please do some research and use facts to support your opinion.
Montville, IFT 2004

16. Approximate
And identify or qualify your statement as “an approximate” or “within an order of magnitude.”
Montville, IFT 2004

17. Cheat Approximate Scientific Units
(It’s better to have an approximation that you understand than an exact number that is incomprehensible.)
30 grams ~ 1 ounce
500 g ~ 1 pound;
1,000 grams (1 kilo) ~ 2 pounds
(These are “off” by 10%)
1 liter ~ 1 quart
1 meter ~ 1 yard ~ 3 feet.
Altitude of San Madres is 3000 meters ~ 9,000 feet.
1 nautical mile ~ 1 statute (regular) mile

18. Understanding the language.
ppm is tiny – 1 inch in 16 miles
 ppb is tinier- 1 cent in ten million dollars
“fecal coliform” is not “feces”
Montville, IFT 2004

19. Eating Bread Causes Cancer
False reasoning:
Furfural causes cancer
Bread contains furfural
Eating Bread Causes Cancer
Montville, IFT 2004

20. Does eating bread cause cancer?
1 slice white bread contains 167 µg (micrograms)
of furfural.
Rodent carcinogenic dose of furfural = 197 mg (milligrams)/kg (kilogram) body wt/day = 197,000 µg/kg/day. (1 mg = 1,000 ug)
Equivalent human dose, 70 kg (150 lb) person
= 197,000 x 70 ÷ = ,600 slices of bread
(dose) x (weight in kg) ÷ (amount per slice of bread) = slices of bread
Montville, IFT 2004

21. T
One (political) case studies from the annals of the FDA’s Food Advisory Committee
Note: An expert need not be a toxicologists, but must know how to think.
Montville, IFT 2004

22. Patulin in Apple Juice Would limiting patulin in apple juice to 50 ppb protect public?
U.S. apple industry in favor of this regulation. (Why?) Several issues-
-Does the public need to be protected?
-How much of the population should be protected?
-Will 50 ppm be enough? (Why not “zero?”)
Montville, IFT 2004

23. Case Study 1
Patulin in Apple Juice Would limiting patulin in apple juice to 50 ppb protect public?
NoOservableEffectLevel (NOEL) = 0.3 mg/kg bw per week
Add 100-fold safety factor
Provisional Max Tolerated Daily Intake (PMTDI) = 0.43ug/kg bw per day
Montville, IFT 2004

24. Case Study 1
Patulin in Apple Juice Would limiting patulin in apple juice to 50 ppb protect public?
NoOservableEffectLevel (NOEL) = 0.3 mg/kg bw per week
Add 100-fold safety factor
Provisional Max Tolerated Daily Intake (PMTDI) = 0.43ug/kg bw per day
If a juice is 100% over the PMTDI, is it really dangerous?
Montville, IFT 2004

25. Case Study 1 Patulin Data Analysis
Juice Samples from Current Production
Age Group
Ave. Juice Intake
(g/person/d)
Ave Patulin Exposure
(µg/kg-bw/d)
90th %
Juice Intake (g/p/d)
Patulin Exposure
(µg/kg bw/d)
All ages
200
0.094
250
0.22
1 -2 years
216
0.58
434
1.3
<1 year
128
0.50
372
1.1
Ae Group
Mean Apple Juice Intake (g/p/d)
Mean Patulin Exposure (µg/kg bw/d)
90th Percentile Apple Juice Intake (g/p/d)
90th Percentile Apple Patulin Exposure (µg/kg bw/d)
0.031
0.078
0.17
0.42
0.13
0.38
Remember, PMTDI = 0.43 ug/kg bw/d
Is a regulation needed?
Remember, PMTDI

26. Case Study 1 Patulin Data Analysis Without regulation All age groups
90% of population consumes < 0.22 ug/kg bw/day
No need for regulation
1-2 year olds
90% of population consumes < 15 ounces juice
consumes ~ 1.3 ug/kg per day
Regulation needed

27. Food Advisory Committee Concerns
Case Study 1
Food Advisory Committee Concerns
Advisory Committee:
Input data
15 ounces seemed “low”
What is consumption beyond 90% of the population?
Is it enough to protect 90% of the children?
Mix of “regular” and “baby food” apple juice?
Montville, IFT 2004

28. Case Study 1 Patulin Data Analysis
Exclude Data for Juice Samples with Patulin > 50 ug/kg d
Age Group
Ave. Juice Intake
(g/person/d)
Ave Patulin Exposure
(µg/kg bw/d)
90th %
Juice Intake (g/p/d)
Patulin Exposure
All ages
200
250
1 -2 years
216
434 (15 ounces)
<1 year
128
372
OK?
Mean Apple Juice Intake (g/p/d)
Mean Patulin Exposure (µg/kg bw/d)
90th Percentile Apple Juice Intake (g/p/d)
90th Percentile Apple Patulin Exposure (µg/kg bw/d)
434

29. Case Study 1 Patulin Data Analysis No Juice Samples Excluded
Samples > 50 ug/kg Excluded REVISED AFTER FAC CONCERNS
Age Group
Ave. Juice Intake
(g/person/d)
Ave Patulin Exposure
(µg/kg bw/d)
90th %
Juice Intake (g/p/d)
Patulin Exposure
All ages
200
250
1 -2 years
216
434
<1 year
128
372
Mean Apple Juice Intake (g/p/d)
Mean Patulin Exposure (µg/kg bw/d)
90th Percentile Apple Juice Intake (g/p/d)
90th Percentile Apple Patulin Exposure (µg/kg bw/d)
Montville, IFT 2004

30. Case Study 1 Patulin Data Analysis
With regulation excluding juice with >50 ppb
1-2 year olds:
90% of population consumes < 0.67 ug/kg per day
(still higher than 0.43 ug/kg per day PMDTI)

31. FDA Regulatory Conclusion: 50 ppb in juice gives adequate protection
Case Study 1
Data interpreted three ways!
FDA Regulatory Conclusion:
50 ppb in juice gives adequate protection
• “All Age” lifetime consumption gives 400-fold safety factor.
• 1-2 year old exposure slightly > PTDI,
but has 64-fold safety factor.
1- 2 year old exposure levels occur for limited part of
lifetime, therefore acceptable.
Testing methodology would not support limit <50 ppb.

32. Food Fads, Facts, and Politics
How to Sort Them Out
                                                   
Montville, IFT 2004

33. How to sort it out Consider the source
“Peer-reviewed” scientific literature, popular press or web site?
Credentials of the scientist – have they ever published anything in the field? (Check Google Scholar)
Follow the money (or agenda) ((Not always bad, if drug company won’t fund the research, who will?)) (((I’ve taken money from the food industry.)))

34. How to sort it out 2. Look for qualifiers and generalizations:
might, can, possibly, potential, up to, etc
Montville, IFT 2004

35. How to sort it out 3. Beware of Emotional Anecdotes
Montville, IFT 2004

37. How to sort it out 4. Correlation is not causation
There is a high correlation between eating pickles and dying.
Everyone who has ever eaten a pickle died.
Montville, IFT 2004

38. 5. Be number literate How to sort it out
It’s mostly addition, subtraction multiplication, and division.
Montville, IFT 2004

39. “The dose makes the poison.” Dose = concentration x intake
Montville, IFT 2004

40. Too much of a “safe” thing can kill you.
“Woman dies from drinking tap water”
Excessive water consumption can cause hyponatraemic encephalopathy.
Montville, IFT 2004

41. A little bit of poison can cure you.
Before After

42. Beware of the 6. Precautionary Principle
“If we’re not 100% sure, let’s wait.”
Also stated:
“Absence of (harmful) evidence  absence of risk.”
but
Zero risk does not exist.
ipods, cell phones, computer screens

43. The “Precautionary Principle”
Ignores potential benefits of new technology.
Diverts resources from real problems to hypothetical ones.
Makes hypothetical concerns more important than concrete benefits.
Montville, IFT 2004

44. What drives people crazy?
Concern = control x risk
(Risk = hazard x probability)
Montville, IFT 2004

45. Causes of concern New, Unknown Not dread Voluntary Dread Involuntary
What, me worry?
Old, Known
Montville, IFT 2004

46. Unknown Not Dread Dread Known Anthrax (you) Anthrax (me) DNA Research
Nuclear Power
Herbicides, DDT
Cycling
Skiing
Food Irradiation
Anthrax
(you)
Hair dyes
Jogging
BST
Not Dread
Dread
Anthrax
(me)
Smoking
Crime
Motorcycles
Firefighting
Known
Montville, IFT 2004

47. Loss of Life Expectancy – Bernard Cohen, J. Health Physics
THOUSANDS OF DAYS
Montville, IFT 2004

48. Loss of Life Expectancy – Bernard Cohen, J. Health Physics
Montville, IFT 2004

49. Homework #4
Identify either something that causes concern but shouldn’t or doesn’t cause concern, but should. Discuss why.
Montville, IFT 2004

50. Take-home messages: Examine the underlying data.
Be number literate.
Examine the underlying data.
Understand the process.
People overreact to dread-unknown risk,
while ignoring “every day” established risk. (We drive down the road while talking on our cell phone as we check our hair in the mirror and eat our egg McMuffin®.)
Montville, IFT 2004