A friend of mine had a similar problem when he, a Brit, was studying in the States. He was in the smoking area of a gay bar, when he asked a friend "shall I chuck this cigarette in the bin, or what?" (I.e. "are you going to come over here to take a drag of this cigarette before it's over, or should I throw it away?"). Unfortunately, a common British slang word for cigarette is also a slur for gay people (it is a slur in the UK too, but the cigarette slang word is common enough that if someone hears the F word, they are far less likely to assume it's in a slur context)

On the bright side, apparently my friend hooked up with the guy who punched him, after my friend admonished him for being so rude as to punch a person in a country without free healthcare. Apparently Southern English accent gets you far in the States