Consumers Misperceptions on Food Safety Relating to MRLs and Pesticides
Kevin Armbrust and Danesha Seth Carley
Critical Thinking Skills in Science
- Gather all information before forming an opinion
- Understand all terms and concepts
- Question the methods
- How was information acquired?
- Question the source
- Hidden biases and assumptions?
- Question the conclusions
- Are they drawn from facts?
- Other interpretations possible?
- Tolerate Uncertainty
- Uncertainty is inherent in risk assessment
- Examine the big picture relationships and systems
Cognitive Biases affecting Public Perception of Pesticide Risk
- Availability of information bias – assign importance to that which comes readily to mind.
- Example: News report on people getting cancer from pesticides; therefore this must be a frequent occurrence.
- Representativeness bias – two similar things are more closely correlated than they are.
- Example: This fungicide can cause cancer in lab tests, therefore its metabolites must cause cancer.
- Anchoring bias: basing risk on the first piece of information you are given.
- Example: I heard on the news this pesticide causes cancer; so if I am exposed to it in any way I will get cancer.
Impacts of Pesticide Safety Misperceptions
- Detections of chlorothalonil metabolites in groundwater resulted in the use being banned in Costa Rica and parts of Europe.
- Pesticides banned for perceived environmental and human health issues can negatively impact trade of imported crops where the use is legal.
- No evidence chlorothalonil metabolites are toxic. Exposure does not equal a toxic effect.
- Detections in breast milk are an artifact of the analytical method, suggest the body is conducting normal metabolic processes to excrete chemical agents.
- Metabolite residues in groundwater from local use are unrelated to parent chemical residues on imported food commodities.
How to people perceive risk?
- Experts base risk on quantitative measures.
- e.g. probability of occurrences
- Lay people have a broader definition of risk in assigning importance:
- Immediacy (will it happen now or later?)
- Catastrophic potential (how many people killed at once?)
- Voluntariness (Do they have a choice?)