When McKay and Sheppard are discussing whether to tell the Hoffans about the Wraith threat, they walk right by a guard. He could've easily informed his superiors about what he heard.
When they are testing the drug's effectiveness on 'Steve', the human volunteer's shirt goes from being buttoned up to unbuttoned in the background. Then, when he enters the cell, it's buttoned up again.
When 'Steve' collapses to the floor in his cell, his coat falls open to reveal his human-coloured midriff.
In the lab scene, at about 8 minutes, the GE logo could be seen on the center plate of the floor-standing fan, even although this is an alien planet.
The wording "Spencer Buffalo, NY" is seen on the microscope in the Hoffan laboratory while Carson is checking out the Wraith biological weapon.
Very briefly, during the lab scene, between 5 and 10 minutes, the brand name "Reznor" (an American-made product) can be seen on the heater hanging from the ceiling.