it could be a number of issues, first it was basting spray..a petroleum based product..there will be issues...

secondly, if the fabric was not PREwashed, the chemicals on that fabric can/will react to the chemicals in the basting spray...

after that, it could be brand, age, how heavy she sprayed, so many things...

basting spray is just never a good thing...

Glad I never use it! Won't start now!