Rumour has it it's going to be a good autumn for blackberries, and certainly they are beginning to ripen on Tooting Common. We walked the dog there in the rain today and saw one forager deep in the undergrowth with his Tupperware, taking advantage of the lack of competition.
I eat blackberries straight from the bush and always have done. Almost everything we touch is covered in bacteria, nearly all of it harmless, and if London is polluted I am breathing it in every day. However, if you are concerned simply wash your fruit well at home, or leave to stand in cold water with a little salt added, then rinse.
Blackberrying gives you free, organic berries with no 'food miles' attached, packed with antioxidants, fibre and vitamins C, K, folic acid and manganese, that can be eaten quickly and so keep their nutrients intact. More importantly for me, it's the chance to connect physically with the seasons in a really rewarding and memorable way.