Genetically modified foods - Safety concern

Safety concern: That long-term potential risks to the environment and human health are unknown.

When: A Boston College professor dubbed genetically modified crops "Frankenfood" in a 1992 New York Times letter to the editor, responding to the FDA's decision to exempt them from case-by-case review. In 1994, tomatoes became the first genetically engineered whole product to go on the market.

Why: The FDA found that genetically engineered tomatoes were as safe as other tomatoes, but not without protest from environmental and consumer groups like the Pure Food Campaign.

The FDA has evaluated more than 50 bioengineered foods it has found as safe as their conventional food counterparts. But the European Union has not approved a genetically modified crop in 10 years, although escalating food prices have led some countries to reconsider their stance on genetically modified crops, which are often resistant to disease and produce high yield rates.