The tax break down comes to:

US International Departure Tax $13.70
Italian Security Bag Charge €2.05
Italian Security Charge €1.81
Italian Embarkation Tax €6.63
US International Arrival Tax $13.70
Greek Security Charge €3.20
Greek Passenger Terminal Facilities Charge €11.20
Greek Airport Development Charge €22.00
US Customs Fee $5.00
US Immigration Fee $7.00
USDA APHIS Fee $3.10
US September 11th Security Fee $7.50
US Passenger Facility Charge $9.00

Although generally, on award tickets, you don't pay the PFCs or the US International Departure/Arrival tax... the best way to find out what you were charged is to look at the fare calculation portion of your receipt. It should break down most of the taxes.