Curiously only find spurious technical data about this chemical, and only recently in the UK.
Did find it being classed as a new variant of the previously banned herbicide, 2,4-D.
What lethal dose studies I could find though make me wonder though: From the above news nothing is really mentioned of health problems of the associated animals? Same as with the studies very little effects noted.
So just because it is present doesn't really give to much to do anything about it.
Which would lead me to say that the above stated Zucchini{Courgette} is probably fine to eat {its a fruit} unlike the majority of the susceptible & questionable veggies are roots/tubers or foliage.