I feel compelled to ask, how is it that you imagine Colombo to be some sort of version of Los Angeles circa 1970? The way you make it sound, all of us are walking around choking in a cloud of toxic smog...
Funny, because I live in central colombo and both walk around AND drive around in an open topped car on occasion, I've never actually had "clouds of toxic black smoke" spewn in my face.
Perhaps you unknowingly suffer from the disease Imaginationicus Overactivus?