Tumbleweed writes

Plants are full of insecticides but I suppose you eat them all the time.
Seems daft to me. FWIW when tested using the same mechanisms as for man-made
pesticides, 50% of the naturally evolved pesticides tested were found to
cause cancer including chemicals in brocolli, lettuce and coffee.

See ames evidence to congress (well some committee, anyway).

====== a reply I wrote recently

Very many plants are toxic. I have read that some 15% of the drymatter
of typical plants comprises toxins (but I find this hard to believe).

Most toxins seem to be directed primarily at insects. That's hardly
surprising as they are the major pest of plants.

Typically only a small range of insects will feed on any given plant,
they will die or not thrive on another species simply because they are
not adapted to cope with toxins other than that of their selected plant.

Some insects concentrate the plant toxin to render themselves poisonous.

Some toxins found in plants:

Curcubin - squash/courgettes (killed a numebr in NZ a few yrs ago).
Solanin - members of the potato family.
Mustard oil - brassicae

A few plants I have forgotten the toxin name:
celery
cottonseed
red kidney beans

Note that many edible plants are packed with toxins, it makes them easy
to grow because they have few pests.

Plants also arrange for a number of physical barriers, hairs and sticky
gums for example.

Capsicain (sp) - the 'hot' bit of chillies is not hot to birds.

Many tree leaves (eg oaks) pack their leaves with tannins, that bind
protein so it cannot be digested. This drastically reduces or stops
growth in many pests.

NB

One I forgot, which is well documented, is phytoestrogens.

These are very common in plants and in some members of the legume family
are at high enough levels to cause serious effects on breeding.

It's long been known that feeding ewes on clovery swards at tupping time
can result in a near total failure to conceive because the ewes do not
cycle, effectively the phytoestrogen level in the feed acting in the
same way as 'the pill'. What this level of oestrogens does to the ram I
do not know.

Basically, in the few hundred million years animals have been eating
plants, one ought to expect a wide, varied and devious range of
mechanical and chemical armaments to have been evolved, together with
countermeasures.

Nature rarely disappoints.

======================

There is no reason to believe that naturally occurring pesticides will
be safe to humans (and rather the contrary) and of course none have been
tested and approved in the way that pesticides are.

Either the tests are wrong, or plants are just as dangerous as the man-made
chemicals you complain about and are actually more dangerous than ones that
havent been shown to cause cancer.

Indeed.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
Note: soon (maybe already) only posts via despammed.com will be accepted.