Manufacturers have until the end of 2021 to comply with a new United States Department of Agriculture (USDA) labelling regulation for food with GMO ingredients.

Although the deadline was drawing closer, the level of compliance was still uncertain, according to a report by Agriculture.

“Nobody knows the answer to that,” Greg Jaffe, who tracks biotechnology for the consumer group Center for Science in the Public Interest, was quoted as saying.

As many as one of every six foods containing GMOs could be exempt from labelling due to loopholes in the USDA regulations, Agriculture reported the Environmental Working Group as saying.

Highly refined sugars and oils from corn, soyabeans, canola and sugar beets were exempted because they did not contain detectable amounts of genetic material although food companies had the option to disclose them, Agriculture said.

The GMO labelling law was directed at grocery products, according to Agriculture, with food sold by restaurants and delicatessens, or served by airlines not required to carry bioengineered labels even if the items were produced with GMOs. Meat, poultry and egg products were also not covered by the labelling law.

Passed by the US Congress in 2016, the National Bioengineered Food Disclosure Law directed the USDA to establish a national mandatory standard for disclosing foods that are or may be bioengineered and this led to the announcement of the National Bioengineered Food Disclosure Standard in December 2018.

Bioengineered foods are defined by the standard as those that contain detectable genetic material that has been modified through certain lab techniques and cannot be created through conventional breeding or found in nature.

The Agricultural Marketing Service (AMS) developed the List of Bioengineered Foods to identify the crops or foods that are available in a bioengineered form throughout the world and for which regulated entities must maintain records. These records will inform regulated entities about whether they must make a bioengineered food disclosure.

The standard requires food manufacturers, importers and certain retailers to ensure bioengineered foods are appropriately disclosed. Regulated entities have several disclosure options: text, symbol, electronic or digital link, and/or text message.

Additional options such as a phone number or web address are available to small food manufacturers or for small and very small packages.