I don't know - I haven't got a Mac to test it on. :)
The Friendly Manual doesn't mention any "qualifiers" at all for "-f macho", so there probably aren't any. Apparently "-f macho" knows the names ".text", ".data", ".rodata", ".bss"... and that's all(?). I would have thought it would accept qualifiers similar to "-f elf" (alloc, exec, write, etc.), but apparently not... I think the qualifiers you're trying to use are for "-f obj", and while Nasm may not complain in "-f elf", I don't think they're doing anything for ya. Same for "-f win32", but I'm less sure of that...
I'd tell ya to ask around the Mac site, but I suppose they'll just tell ya not to use assembly language. Sigh. I may have to acquire an accursed Mac, just to test this stuff. :(
Good Luck,
Frank