Module 3 Home

Biological Lab

Social Science Issue

Process of Science

Web Exercise

As you learned in Module 3 - Social Science, some people are concerned about the risks involved in creation of genetically modified organisms. As is turns out, risk evaluation is best performed using the same hypothesis-driven approaches used in answering other scientific questions (see Module 2 - Process of Science and Module 2 - Web for background on hypotheses)

Note: the following discussion is condensed from some excellent resources available through USDA-University of Florida and University of Nebraska. For a more detailed exploration of these topics, go to: USDA: The Science behind Risk Assessment and UNL AgBiosafety for Educators

Example questions whose answers involve risk-assessment: Is genetically engineered food dangerous to human health? Does over-use of antibiotics lead to antibiotic resistant bacteria? When is the next big hurricane going to strike?

Definitions of terms used during Risk Assessment: Hazard - inherent ability of a substance or activity to cause harm Exposure - probability and/or amount of contact between the hazard and the thing it harms Risk - potential harm as determined by: the degree of the hazard the amount of exposure

Stages of science-based risk assessment identify a potential hazard quantitate the risk associated with the hazard explore the consequences associated with the hazard Science-based risk assessment is based on factual information rather than feelings or rumors. Consequently, the actual risk associated with a given hazard is often very different than what we might perceive it to be. For example, many people fear flying in airplanes, when driving a car is actually far more dangerous. Science-based assessment of risk is similar to scientific analysis of anything else. Review of what science is and what it can do

Example of science-based risk assessment From: Technical report on the FSA project “Evaluating the risks associated with using GMOs in human foods (British Food Standards Agency) Hypothesis: Bacteria living in the human intestine can move transgenes from food to human cells. Experimental Approach: Two microbes that live in the human gut, Salmonella typhimurium and Lactabacillus, were engineered with a transgene similar to that found in genetically modified soy, and incubated with intestinal cells grown in culture After incubation, the intestinal cells were analyzed for presence of the transgene. None of the intestinal cells were found to contain the transgene. Conclusion: No evidence was found to support the hypothesis that intestinal microflora can directly or indirectly transfer genes from genetically modified food to cells in the intestinal epithelium.