"......... lets say that we have a vegetable that is sprayed with a
pesticide. The pesticide says that after 15 days it gets degraded to non
toxic elements..............."

What this in fact means is that the pesticide will be inactive within about
7 days, the rest of the time is the safety barrier that the company has to
have to allow for people using it stronger than it should be, for adverse
weather conditions etc that may slow down the plants metabolism.

As for washing the veg/fruit this does nothing for systemic sprays, but
with the re introduction of old so called organic sprays then washing is
good as most will remain on the surface.
Also a lot of fruit is either sprayed or dipped after picking to maintain
condition in the box during transit and storage.

Finally...when it comes to buying from local "certified" organic growers
(and many will say that anyone in the UK trying to make a living from
growing Organic should be certified), the organic prices are falling every
year and several large organic growers in the UK have given up as they can't
make it pay any longer even using foreign labour for harvesting.
This is largely due to the imported "Organic" produce being imported from
low wage economies.
Where Spain was one of these a few years ago, now the Spanish growers are
having to use imported labour (Mostly Moroccan) as the Spanish workers are
now to expensive to employ.
In the UK it is getting very hard to find British people to work on the land
and every year many thousands of foreign workers come here to harvest fruit
and veg.
This reminds me of the 50's when we brought in West Indians because the
British wouldn't do jobs like bus driving etc.

--
David Hill
Abacus nurseries
www.abacus-nurseries.co.uk