Anyone still using Bordeaux mixture? Now that is a rather nasty throwback to times gone by!
I couldn't disagree more - it is a very simple poison and utterly predictable in its original form of colloidal copper made from copper sulphate and slaked lime solutions mixed as needed and used immediately - though that's before they messed with it to make it more "convenient" ie. easier to sell at a higher price (but with different ingredients that can be used as a powder in water).
It has been used safely since 1840 - unlike the modern chemicals that are too complicated to ever be fully tested for the unpredictable and insidious effects that always appear -
despite following the instructions, but only 40 or 50 years later.
Actually calling it a poison is moot - copper is an essential element in mammalian metabolism - the easiest copper sulphate to find is sold as a food additive for livestock.
It is a trace element but one of the most important 4 - so you'd have to be very determined to harm yourself with the mix** - it is incredibly bitter. However if you see that blue colour on your tomatoes then just polish it off on your sleeve - if you can't taste what's left it can't harm you. If you managed to make yourself sick then you really deserved that Darwin award.
**Reminds me of the cartoon of an arm emerging from a meat grinder, still holding the handle - labelled as "the world's most determined suicide".
Humans' broad diet generally provides enough (about 1 or 2mg a day on average), but livestock (on a monotonous diet) need supplements.
Massive use can harm earthworms, but that's why they should invert the normal practice - if they ban it, the ban should be for farmers
NOT hobbyists. While they are at it they could ban the ready made powder for novices to dilute,
not the use of the real thing.
On a personal note - I don't understand why people spray their potatoes for blight - you simply need to dig them up as soon as they are hit, use the crop as earlies and buy maincrop ones as you need them - leaving lots of space for properly tasty stuff that is too expensive (or often impossible) to buy from the shops.
Cheers.
PS. all the Dithiocarbamates and anything else with a name containing "thi" (mancozeb=dithane and vice versa) are dodgy and overdue for banning - but what you really notice is that they all make your tomatoes taste of rotting cabbage!