FDA Approves Lab-Grown Pork Without Long-Term GMO Growth Hormone Studies

Mission Barns has received an FDA approval for its lab-grown pork product, which will be sold at Fiorella restaurants in San Francisco and Sprouts Farmers Market grocery store. The FDA did not test the product, but relied upon the company to present its science, methodology and the FDA has “no questions.”

The FDA approval letter states:

“We have no questions at this time regarding Mission Barns’ conclusion that foods comprised of or containing cultured pork cell material resulting from the production process defined in CCC 000008 are as safe as comparable foods produced by other methods. However, as you are aware, it is Mission Barns’ continuing responsibility to ensure that foods it markets are safe, wholesome, and in compliance with all applicable legal and regulatory requirements, including those administered by FSIS. Should new production procedures, cell lines, or substances employed during production be used that could be relevant to the safety of the food, we strongly recommend that Mission Barns contact FDA.”

The FDA relied entirely upon the scientific evaluation provided by Mission Barns in its approval and has no further questions. The final product has trace amounts of metal, including nickel (0.06 ppm), Vanadium (0.02 ppm), and molybdenum (0.01 ppm). The reported levels by Mission Barns are far below the levels typically found in traditional pork (0.201 ppm nickel, 0.034 ppm vanadium). Nickel is an allergen that affects 10-20% of the population with contact dermatitis. Vanadium has gastrointestinal and renal toxicity at much higher doses.

The FDA’s response to Mission Barns’ scientific data states:

“Mission Barns utilized in silico bioinformatics tools and conducted a literature search to evaluate the allergenicity potential of a genetically engineered recombinant porcine growth factor used during the production process. The firm states that the modification, which increases the recombinant growth factor’s affinity for its cognate cell surface receptor, is not expected to alter the allergenic potential of the modified protein compared to the growth factor that naturally occurs in pork.”

Mission Barns is comparing genetically modified growth hormones with an altered amino acid sequence to naturally occuring growth hormones (IGF-1 and somatotropin) that are naturally created by the pig. The data provided to the FDA that posits there are no health concerns regarding the use of this hormone rely on predictive models rather than human clinical trials.

Growth hormones are prohibited in hogs and pigs. The USDA states, “Hormones are not allowed in raising hogs or poultry. Therefore, the claim “no hormones added” cannot be used on the labels of pork or poultry unless it is followed by a statement that says “Federal regulations prohibit the use of hormones.”

Since the growth hormone is used in vitro to grow cells and not used on live animals, it is not bound by the USDA hormone ban. New GMOs that are introduced in food products are overseen by the FDA, but submission of testing data is voluntary. The FDA states, “In 2024, the FDA issued a guidance for industry that describes how firms can voluntarily engage with the FDA before marketing food from genome-edited plants.”

GMO seeds are regulated by the USDA and may be regulated as the seeds are directly sold to the general public. This genetically modified hormone is used during Mission Barns’ production of lab-grown pork, so it falls fully under the FDA’s jurisdiction. The company supplied this information voluntarily during the regulation process and the FDA said it has no questions or concerns about the safety of the product.

The Endocrine Society defines Endocrine-disrupting chemicals (EDCs) as “an exogenous chemical, or mixture of chemicals, that can interfere with any aspect of hormone action.”

The Endocrine Society states, “Non-monotonic dose responses (NMDR) occur when the slope of the curve relating dose and effect changes sign at some point within the range of the doses examined. This phenomenon is particularly common in the case of hormones and EDCs. The presence of NMDR has been extensively demonstrated in animal and cellular models and the diverse and complex molecular mechanisms underlying NMDR are beginning to be demonstrated. Importantly, current epidemiological studies are starting to reveal their existence in human populations as well.”

The FDA evaluation states that Mission Barns’ testing data shows the growth hormone is present in the harvested cell material at “very low or undetectable levels.” This is lower than the amount of natural growth hormone detected in traditionally produced pork, but this is a novel genetically-modified hormone and there are no long-term studies measuring dietary responses to modified proteins. 

The Endocrine Society states, “The existence of NMDR in evaluations of EDCs has significant consequences on regulatory toxicology, because it does not guarantee that the lack of adverse effects at high doses also confirms safety at low doses.” The Endocrine Society adds, “The existence of NMDR raises the possibility that reduced exposure may have uncertain effects on risk, making it very difficult to predict a safe level of exposure.”

Lab-grown meat is a technology and product supported by Bill Gates and others for the potential to reduce greenhouse gases and prevent climate change. A 2023 preprint study of the environmental impacts of lab-grown meat found “The fossil fuel depletion for scenarios with purified growth medium components were approximately 3 to 17 times greater than the reported high for boneless beef.”

The study’s authors note the potential harm of not purifying the growth medium to remove endotoxins. They write, “In cell culture the presence of endotoxin can have a wide variety of effects. For example, at an endotoxin concentration as low as 1 ng/ml it reduced pregnancy success rates by 3 to 4-fold during in vitro fertilization of human IVF embryos (Dawson, 1998; Fishel et al., 1988; Snyman & van der Merwe, 1986).”

The HighWire reported last year about the USDA’s approval of “Piggy Sooy,” a soybean genetically modified with pork proteins.