Last year, the House passed a bill to preempt states from imposing mandatory labeling of genetically engineered food (GMOs). But as Daren Bakst notes, “While it looked like the Senate was going to follow suit, in the last minute, the new Senate bill would actually effectively mandate the labeling of genetically engineered food.”

“In the Senate bill, there would be a national mandatory labeling requirement unless the Secretary of Agriculture determines that there has been substantial participation by labeled foods in voluntary labeling,” says Bakst. “The Secretary has to develop regulations to clarify the process, but there has to be at least 70 percent substantial participation after two years.”

Here is what you should know about GMOs and GMO food labeling:

What are genetically modified organisms (GMOs)?

Genetically modified organisms (GMOs) are organisms (i.e. plants, animals, or microorganisms) in which the genetic material (DNA) has been altered in a way that does not occur naturally by mating and/or natural bination. The technology used for GMOs is sometimes called “modern biotechnology,” “gene technology,” or “genetic engineering.” The process allows selected individual genes to be transferred from one organism into another, also between nonrelated species. Foods produced from or using genetically modified organisms are often referred to as genetically modified (GM) foods or GMO foods.

Why are GM foods produced?

According to the World Health Organization (WHO), GM foods are developed “because there is some perceived advantage either to the producer or consumer of these foods. This is meant to translate into a product with a lower price, greater benefit (in terms of durability or nutritional value) or both.”

Which plants are genetically modified?

The mon genetically modified plants are corn, canola, soybean and cotton. Based on USDA survey data, the adoption of genetically modified crops in 2015 was: soybeans, 94 percent of US crops; cotton, 94 percent, corn 92 percent.

Which foods are made from genetically engineered plants?

According to the FDA, the majority of genetically engineered plants are typically used to make ingredients that are then used in other food products. Such ingredients include “cornstarch in soups and sauces, corn syrup as a general purpose sweetener, and cottonseed oil, canola oil, and soybean oil in mayonnaise, salad dressings, cereals, breads, and snack foods.”

Why do some people oppose GMOS?

GMO critics claim that foods made from GMO crops — which they often refer to as“Frankenfoods” — can cause environmental damage and health problems for consumers.

“The genetic engineering of plants and animals is looming as one of the greatest and most intractable environmental challenges of the 21st Century,” says the Center for Food Safety. The Non-GMO Project says that, “Most developed nations do not consider GMOs to be safe. In more than 60 countries around the world, including Australia, Japan, and all of the countries in the European Union, there are significant restrictions or outright bans on the production and sale of GMOs.”

The Non-GMO project also claims GMO crops pose a threat to farmers:

Because GMOs are novel life forms, panies have been able to obtain patents with which to restrict their use. As a result, panies that make GMOs now have the power to sue farmers whose fields are contaminated with GMOs, even when it is the result of inevitable drift from neighboring fields. GMOs therefore pose a serious threat to farmer sovereignty and to the national food security of any country where they are grown, including the United States.

Are genetically modified foods safe to eat?

In the U.S., the Food and Drug Administration (FDA) regulates the safety of foods and food products from plant sources including food from genetically engineered plants. Foods from genetically engineered plants must meet the same requirements, including safety requirements, as foods from traditionally bred plants. The FDA has found that GMO foods are “generally as nutritious as foods parable traditionally bred plants.”

The European Union (EU) conducted a lengthy study on the biosafety of GMOs and found:

The main conclusion to be drawn from the efforts of more than 130 research projects, covering a period of more than 25 years of research and involving more than 500 independent research groups, is that biotechnology, and in particular GMOs, are not per se more risky than e.g. conventional plant breeding technologies.

Additionally, the World Health Organization, the American Medical Association, the U.S. National Academy of Sciences, the British Royal Society, the American Association for the Advancement of Science, and numerous other organizations have examined the evidence e to the same conclusion about the safety of GMOs.

Do GMO foods need to be labeled?

Because some consumer interests are interested in whether food ingredients are derived from genetically engineered plants, some manufacturers choose to voluntarily label their foods as containing or not containing GMO-based ingredients.

However, many businesses, non-profits, and scientific organization oppose mandated labeling. As the American Association for the Advancement of Science says:

There are several current efforts to require labeling of foods containing products derived from genetically modified crop monly known as GM crops or GMOs. These efforts are not driven by evidence that GM foods are actually dangerous.

[. . .]

It is the long-standing policy of the Food and Drug Administration (FDA) that special labeling of a food is required if the absence of the information provided poses a special health or environmental risk. The FDA does not require labeling of a food based on the specific genetic modification procedure used in the development of its input crops. Legally mandating such a label can only serve to mislead and falsely alarm consumers.