In an interview with The Guardian, Nibali was eager to separate two of the four doping positives from his WorldTour team.
Iglinskiy brothers Maxim and Valentin, part of the Astana WorldTour team, both failed tests for EPO this season, with Maxim forming part of Nibali's Tour-winning squad.
In October a third Astana rider, Ilya Davidenok, tested positive for anabolic steroids, followed by the announcement this week that Victor Okishev from the Astana continental team also tested positive for steroids. All four riders are from Kazakhstan.
"This guy (Davidenok) is not from our team," Nibali told The Guardian.
"Astana has a satellite team of youngsters. It's a completely different team. I dug up a little info on him because I didn't even know who he was. I discovered he was racing with the Kazakh national team.
"So only the brothers were really associated with Astana and the Kazakhstan federation has been very tough on them. It's right that they should."
The Italian said he was shocked when he heard about Maxim's positive.
"Apart from the obvious reaction Ã¢â¬â anger Ã¢â¬â my main feeling was that this was unbelievably stupid. It did not make any sense. He had just renewed his contract. He did not have a massive goal to chase.
"Our sponsors in Kazakhstan weren't happy at all. We were in Kazakhstan the week after (at the Tour of Almaty) and there was such a feeling of betrayal because he is a Kazakh rider."
Nibali laments his team - and his Tour victory - being associated with cheats and labelled any rider who attempted to cheat the system as 'stupid'.
"The great things we're trying to achieve can be jeopardised by a single
rider. That's why it's so upsetting. One mistake can ruin so much. But I
believe cycling is the cleanest sport because of all the doping
"Today we have a biological passport, regular doping control, race controls. If you are doping, you will be caught. Even if the technique of doping can be advanced you will still be caught in another four years. It makes me laugh. Risking and cheating today is for stupid people."