Our Family Farms

GMO Purple Tomato Update

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By Dr. Ray Seidler, Our Family Farms Advisory Board Member

I recently received an email from one of OFF’s special friends, Anna Cassilly, who said:  Gardeners can now grow a genetically modified (GM) purple tomato”.

“Too much of a good thing?”

In September, 2022, the US Department of Agriculture declared that a genetically engineered purple tomato (produced by Norfolk Plant Sciences, UK) is not subject to regulation because the USDA did not identify any potential plant pest risks associated with the plant.       

In July 2023 the Food and Drug Administration (FDA) declared they had no further questions concerning the purple tomato i.e., they concluded that when consumed as food by humans, this GMO product posed no safety risks. In 2024 GMO purple tomato seeds went on sale to individual stores including gardeners in the United States. It is the first genetically modified food crop to be directly marketed to home gardeners.

Following these decisions, the company is ready to introduce a variety of genetically modified (GM) purple tomato products (ketchup, salsa, tomato sauce?). These facts are very disturbing.

How will you know if YOUR purple tomato is GM? How will you know if those purple seeds are GM? Might the GM tomato cross pollinate with other tomato varieties you are also growing? Do you save tomato seeds from your garden for replanting? Would the GM purple tomato hybridize with your other tomato plants?

The GM Purple Tomato has purple flesh, skin, and seeds, not just purple skin seen in natural purple hybrid tomato varieties. However, the very dark purple interior will flag that it is a GM tomato. The dark purple appearance of the GM tomato reflects the hyped-up concentrations of the pigmented anthocyanin chemicals that are produced throughout the entire tomato fruit. There is no defined maximum daily dose nor regulatory recommendations of maximum daily intake of antioxidants like anthocyanin. It is widely believed that a little bit of anthocyanin can be very beneficial to human health. But a lot? How much is too much? Here is what scientists have discovered about dosing on anthocyanin.

A half cup of the GM purple tomatoes contains some 40 times more than the entire average daily human consumption of anthocyanins. Isn’t more better?  NO!  The natural dark fruits and vegetables like dark grapes, blueberries, black beans, and plums contain anthocyanins on a weight basis in the range of 12 to 500-fold less than the GM purple tomato.

Forty milligrams (40mg) per day of anthocyanins taken as pill supplements might be a concern to Harvard scientists. However, it  would be easy to consume 500mg of anthocyanins found in 100gm (3.5 ounces) of the fresh GM purple tomato.

Scientists from Copenhagen, Denmark from the Centre for Clinical Intervention Research have declared, “Antioxidant supplements (pills) do not possess preventive effects and may be harmful with unwanted consequences to our health, especially in well-nourished populations."  No large scale long term safety studies have been published on GM tomatoes.

It is easy to consume too much antioxidants by taking pills since there are no regulations on advertisements and hype. What about purple tomatoes with some 3-10-times the amount of anthocyanins as contained in most supplements

In some cases, supplementation trials (with pills) of antioxidants have been associated with adverse effects, including increased mortality or stroke and liver damage. Animal studies indicate that high dose polyphenol supplements may damage your kidneys, cause tumors, or unbalance your thyroid hormones. Concerns regarding effects and interactions with medications also arise with the promotion of polyphenol consumption (like anthocyanin) at levels far above natural occurrence.

A conventionally bred dark tomato called Sun Black contains only 7 mg of total anthocyanins per 100 gm fresh tomato, which is very likely, based upon visual examination, to be typical of other dark conventionally bred tomatoes. 

Do you know that Jackson County Oregon is only 1 of 8 U.S. counties that has a special ordinance that prohibits the planting of Genetically modified (GM) seeds thanks to local voters and Our Family Farms? OFF reminds you that through passage of Ordinance 15-119 ten years ago, we are protected from GM plants being grown in this county. Actual purple tomatoes however, may be found for sale in local markets.  

OFF needs your help to tell us if you see any of these seed packets or tomatoes for sale anywhere in Jackson County. A seed packet might be labeled, “contains bioengineered  ingredients." The seeds will be dark purple. If you encounter a purple colored tomato, it may not be genetically engineered. Fortunately, you can look at the small sticker attached to the tomato. These price lookup codes (a series of numbers) can be found attached to each tomato being sold in a store. Any number that begins with a 9 is organic and cannot be genetically engineered.

If you encounter a likely GM seed or GM purple tomato please let us know at [email protected]

GMWATCH authors have recently taken a deep dive into the safety issues associated with purple GM tomatoes.