Skip to main content

Mandatory Biotech Labeling in California: The Impact of Prop 37

On Election Day, California voters will be asked to decide whether to require labeling of genetically engineered (GE) food sold in California. The GE labeling initiative will appear on the ballot as Proposition 37. If successful, the California Right to Know Genetically Engineered Food Act (the Act) will require clear and conspicuous labeling on GE food.[1] The Act will also further prohibit GE foods from bearing labels that imply the food is "natural," "naturally made," "naturally grown," "all natural" or similar terms.[2] Enforcement of the Act would be achieved through private right of action, which would permit citizens to seek injunctions against companies that violate the Act and enable recovery of reasonable attorney's fees and investigatory expenses.

Effective July 1, 2014, GE labeling would be required on foods that have been or may have been "entirely or partially produced with genetic engineering."[3] "Genetically engineered" is defined by the Act as "any food that is produced from an organism or organisms in which the genetic material has been changed" by either using in vitro recombinant DNA techniques or fusing cells in a way that would not occur in nature.[4] Processed foods that have been genetically engineered would have to bear the statement: "Partially Produced with Genetic Engineering" or "May be Partially Produced with Genetic Engineering".[5] While the presence of GE ingredients trigger labeling of the food, the Act does not require the listing or identification of the particular GE ingredients on the label.

There are several notable exemptions set forth in the Act at section 110809.2. Processed foods that contain GE ingredients present at less than 0.5% where there are not more than 10 such ingredients are exempt from GE labeling but only until July 1, 2019. Processed foods that contain GE processing aids or enzymes are exempt from the GE labeling requirements of the Act. Foods that are intended for immediate human consumption or sold in a restaurant or other similar facility are exempt. Foods from animals (e.g., milk, meat and cheese) that ate GE feed are exempt. Finally, alcoholic beverages, organic foods, and medical foods are expressly exempt.

The law's supporters emphasize that its purpose is to allow consumers to make informed choices about whether to buy GE food.[6] Despite failed efforts to institute similar requirements at the national level and in other states, supporters cite to data that suggests consumers would like to see this information included on the label. A 2010 poll found that 93% of those surveyed supported including GE information on labels.[7] While most of the study's participants went on to say that they would still be willing to consume GE fruit, vegetable and grains, nearly 80% admitted that they were either unsure or did not believe GE products were safe.

GE food is believed to be present in 70-80% of all processed foods in the U.S. In a 1992 policy statement and 2001 draft guidance, the U.S. Food and Drug Administration (FDA) communicates their position that GE food is safe. FDA also says in these documents that it "has no basis for concluding that bioengineered foods differ from other foods in any meaningful or uniform way."[8]

Critics of GE food insist that mandatory labeling is necessary because the safety of such food is unknown and there may be unintentional consequences that have not been adequately considered. Many fear that these products could cause increased and unpredictable allergies. Others suggest that GE foods may cause unforeseen environmental impacts, such as creation of pesticide resistant weeds and cross-contamination of non-GE crops.

Opponents of the law have started their own website, "No on 37" to emphasize the substantial costs and inconsistencies imposed by the law.[9] Specifically, the site criticizes the fact that labeling would be required for fruit juice and prepared foods, but not on foods served at restaurants or for bottled wine made from GE grapes. Moreover, labeling requirements might effectively require the use of more costly non-GE products due to consumer preference –even though there may be no safety nor any other benefit to using the more costly product. Opponents see the initiative as politically motivated to benefit producers of non-GE foods.

Although the Act would only impose obligations on products sold in California, if passed, it is expected to have an impact on food producers throughout the country. National food producers would have to either use the same labeling elsewhere or create special labeling for products sold in California.

[2] Section 110809.1.

[3] Section 110809(a).

[4] Section 110808(c)(1).

[5] Section 110809(a)(ii).

[6] See "Yes on 37" at,

[7] National Survey of Healthcare Consumers: Genetically Engineered Food, Thomson Reuters (October 2010), available at,

[8] Food and Drug Administration, Guidance for Industry: Voluntary Labeling Indicating Whether Foods Have or Have Not Been Developed Using Bioengineering; Draft Guidance (2001), available at,

[9] See "No on 37" at,