2,4-D LV6 ester is actually a clue as to the source. Ester formulations are more prone to thermal vaporization during hot summer days than amine formulations and can drift as a vapor rather than a droplet particulate. There have been cases of 2,4-D ester vapor drift vine damage at vineyards from a suspected source miles away. I boom spray my pastures with a 2,4-D amine formulation in the early spring with the separation between the pasture and raised bed garden being less than 5 ft, without sign of chemical damage. My point is that it can be done without crop damage.
There's a famous saying in the field of toxicology "Dose makes the poison." An example would be salt, where a little on your food is perfectly safe but in excessive amounts is can kill you like a poison. There was also an incident where a radio station had a challenge for a prize involving bottled water. One contestant drank so much water that it impacted their electrolyte balance resulting in their death. OK, these are chosen actions by those involved, but there are also involuntary body burdens of radioisotopes that are detectable in your body; those being Carbon-13 and Potassium-40.
I mention this to make the point that there is a significant difference between detection of the material and effect caused by the material when modern analytical tools are employed. To many people, myself included, just stating that something was detected without specifying levels detected is a "red flag" warning to the veracity of the statement. If I read a report where the results were 50 ppt of a regulated material was detected and the legal limit was 1 ppm, I'd shrug my shoulders and look for a situation where action resources would be better applied.
Here's a story that is pretty well written about pesticide contamination:
https://www.latimes.com/california/story/2024-06-14/the-dirty-secret-of-californias-legal-weed
When you have testing done on your produce, quality test results should state the level detected, the uncertainty of the numerical value, and detection limit for the protocol employed.