The Oregon Department of Agriculture (ODA) Pesticides Program, responds to all reports of bee kills or die-offs alleged to be related to pesticides.
I encourage you to report any suspected pesticide issue. I am told that the ODA is very responsive and will conduct an through investication testing for 72 different pesticides.
How to contact ODA
Individuals may file a complaint via"
Email: naturalresource-complaints@oda.oregon.gov
Phone: 503.986.4635
You also can call 211 to report a bee-related incident 24 hours a day
Here is the link.