Dear Angelika,

I´m thinking about treating pianos and furniture containing wool felt with a
spray called Bambule Insektenspray. I´m worried about using pyrethrins. The
Bambule spray contains 7 % teetreeoil and neemoil solved (how ever) in
water. This substances are not poison for humans. It is described, that the
insects will stop eating the textile after 5 - 10 min. and that the effect
will stay for a longer time.
You can get it from: www.aries-online.de May be it´s an alternative?

Julia Dummer
Staatliche Museen Kassel
Germany