How sustainable is lab-grown meat? That’s the question researchers at the University of California-Davis are asking in a new study.

The study’s abstract says consumer interest in animal cell-based meat, also called cultured or lab-grown meat, continues to grow, with some consumers viewing cultured meat as “a viable environmentally conscious replacement for livestock production.”

The problem, the abstract says, is that not enough research has been done on how sustainable the production of lab-grown meat is. This new study aimed to help answer that question.

The UC-Davis research team conducted a life-cycle assessment of how sustainable the production of lab-grown meat is compared to beef, analyzing the energy needed to produce each product and the greenhouse gas emissions at each production stage.

In an initial pre-print research paper that has not yet undergone peer review, they concluded cultured meat production is not as environmentally friendly as it seems.

“Our findings suggest that cultured meat is not inherently better for the environment than conventional beef. It’s not a panacea,” Edward Spang, one of the paper’s authors and an associate professor in the Department of Food Science and Technology, said in a statement.

One challenge with the production for lab-grown meat is that is requires the use of highly refined or purified growth media, which make animal cells multiply. The researchers say this method is similar to the biotechnology used to make pharmaceuticals.

“If companies are having to purify growth media to pharmaceutical levels, it uses more resources, which then increases global warming potential,” Derrick Risner, the paper’s lead author and a doctoral student in the UC-Davis Department of Food Science and Technology, said in a statement.

Risner said if companies continue to produce cell-cultured meats “using this ‘pharma’ approach,” it will be worse for the environment and more expensive than conventional beef production.

Andrew Noyes, a spokesman for GOOD Meat, a cultivated meat company, said the UC-Davis study is based on a flawed premise.

“The UC-Davis study is largely based on arguments that nutrients fed to cells will continue to be pharmaceutical grade,” he said. “That assumption is flawed and doesn’t align with the vision or actions of this young and rapidly evolving industry. For example, the cost of the nutrients that we feed our cells has fallen in recent years and we have demonstrated success with non-pharma grade ingredients in our R&D efforts.”

For the study, the scientists considered broad environmental impacts and defined global warming potential as the carbon dioxide equivalents emitted for each kilogram of meat produced.

Using this metric, they found that a higher volume of greenhouse gases is emitted in the production of lab-based meat that uses growth media compared to traditional beef.

The global warming potential of lab-based meat, the scientists concluded, ranges from 4 to 25 times greater than the global warming potential of average retail beef.

In their paper, the researchers wrote that in the near term, cultivated meat’s environmental impact is likely to be “orders of magnitude higher” than conventional beef.

The researchers, however, did not rule out the possibility that companies might develop more sustainable production methods in the future.

”It’s possible we could reduce its environmental impact in the future, but it will require significant technological advancement to simultaneously increase the performance and decrease the cost of the cell culture media,” said Spang, the associate professor.

Other authors on the paper include Yoonbin Kim and Justin Seigel of UC-Davis and Cuong Nguyen of the University of California Division of Agriculture and Natural Resources.

The research was funded by the UC-Davis Innovation Institute for Food and Health and the National Science Foundation.