In article ,
Spider wrote:

"moghouse" wrote in message
...

I have noticed that runner bean flowers have an allergic effect on
bees - it brings them out in hives.

(sorry, I'll get my coat)

:~) Behive yourself!

Buzz off!

I have heard, David, of people getting a reaction to courgette leaves, but I
don't know whether it's a toxin or not. Maybe it's just the prickliness of
the fruit causing soreness, worsened by the sun? Sometimes, it's as simple
as a concealed nettle. Have you checked?

I did check up on the, er, literature, and the situation is roughly
as follows.

There is a continuous gradation from plants like giant hogweed, rue
and the sumachs (where almost everyone will react to the sap), through
grasses (where many people react) to things like runner beans (where a
few people do). But there are hundreds of widespread UK plants that
fairly often cause reactions.

There is a similar gradation to the sensitivity of people, as with
bee stings, from life-threatening reactions down to trivial and very
temperary rashes. And not everyone reacts consistently between plants.
Runner beans, courgettes and hops cause reactions precisely because
their stems are abrasive, and so can get small amounts of sap through
the skin. More toxic plants cause the problem less often because
they are not.

Perhaps the main reason that this doesn't show up more is that most
saps won't get through most people's skin in most places. I have
reacted to hops when they abraded me in the inside of the elbow, but
no UK sap that I know of will get through the horny skin on my hands.



Regards,
Nick Maclaren.