Yes, of course. That was my point. That the heuristic of "developed country" is not effective just because it's sometimes right. Also take a look at the number

Yes, of course. That was my point. That the heuristic of "developed country" is not effective just because it's sometimes right. Also take a look at the number of contaminants in the water for each those cities in your source. It's not zero for any of them.