This is from Igor b's links that he posted. Translated to English , so there might be some errors. If you use his links directly you will see the photos, references to medical research and sourced information. It should be of interest to those that favour outsiders using a gas grenade also , or force. The dilated pupils are another example of how some sort of toxins were involved, please enjoy this rather detailed explanation and research by Igor b.
Four of the top five tourists (Doroshenko, Krivonischenko, Slobodin, Dyatlov) had dilated pupils. Only in Kolmogorova the state of the pupils is not described. (For obvious reasons, the state of the pupils is not described in the four found in the stream, so we are not talking about them).
10 years ago, questions of statistics of signs of death from hypothermia interested an expert from Khabarovsk Rybalkin R.V.:
"On the frequency of occurrence and probability of signs of death from cold"http://www.forens-med.ru/book.php?id=1891
He did a great job of studying 100 cases of death from cold and freezing.
Interesting things have come to light. For example, it turned out that the “pose of a chilled person”, which was considered almost mandatory for a frozen person, was met only in 2% of cases.
But the main thing is the pupils. Of the 100 examined, 13 were sober and all had constricted pupils. 87 of the frozen ones were drunk and they all had dilated pupils.
Thus, if the cause of death is freezing and the person was sober, the pupils will definitely be constricted (100%).
The examination established the absence of alcohol among tourists. And according to a number of other signs and evidence of Yu. Yudin, there is no reason to doubt their sobriety. Then the most likely cause of dilated pupils is the preliminary poisoning of tourists.
There is still no doubt about freezing as the cause of death. This is indicated by the main, "reinforced concrete" signs of freezing observed in the dead:
Cerebral edema 99%
Juiciness, plethora of the soft integument of the skull 91%
Plethora of heart cavities 95%
Lungs on a dark red section 98%
Vishnevsky's spots 95%
But the version with a certain chemical effect, as the cause initiating the tragedy, receives weighty evidence.
The rest of the versions are inconsistent, because. cannot make pupils dilated when they should be narrow .
Why did the medical examiner overlook this?
The forensic expert Vozrozhdenny could experience a lack of information and accumulated statistical data on this issue at that time.
Modern "invited" experts - because of the lack of practice in this particular type of expertise.
There may be misconceptions that the pupils of the frozen were dilated, allegedly due to darkness. This is not true.
Pupils cease to react to light at the last stage of freezing, even during life. After death, the width of the pupils is controlled by completely different processes.
The pupils are constricted, do not react to light.
The reaction to light is sharply weakened or lost.
The pupils do not care - it is dark or light, the eyelids are open or closed, however, in sober people they will be narrowed in 100% of cases, and in drunken people they will be expanded in 100% of cases.
Lighting conditions do not affect this attribute. Otherwise, it would turn out that all drunk people always freeze only in the dark, and all sober people always only in the light.
Returning to the question of abnormally dilated pupils in those who are frozen sober:
It is safe to say that the answer to the death of the Dyatlovites lies in the cause of dilated pupils .
And the pupils are really very dilated:
( In Igor's b link there is a photo of the dilated eye pupil of Dyatolv)
100% the presence of constricted pupils in frozen sober people was confirmed in another work:
"Death from hypothermia" V.P. Desyatov, 1977
In the corpses of persons who died from cooling while sober, the pupils, according to our observations, turned out to be constricted, while in the case of severe intoxication preceding death, the pupils were dilated in 59%.
In this case, not even all drunks had dilated pupils. Apparently 41% of drunks with narrow pupils were slightly drunk.
But the tourists weren't drunk at all.
First, the medical examiner revived established the absence of alcohol.
Secondly, in the same work by Desyatov, the difference between sober and drunkards is indicated by the color of the mucous membrane of the eyelids:
On non-frozen corpses of persons who died of cold sober, the mucous membrane of the eyelids in all cases was pale pink.
The forensic expert Vozrozhdenny described the color of the mucous membrane of the eyelids only in three: Doroshenko, Krivonischenko, Kolmogorova.
... the pupils are dilated , the mucous membrane of the eyelids is pale pink .
... the pupils are dilated , the mucous membrane of the eyelids is pale gray .(in this case, the pale gray color can be caused by the so-called "weathering", because Krivonischenko was lying face up and was almost not covered with snow)
The mucous membrane of the eyelids is reddish in color.
The reason for the expansion of the pupils could be the wolverine's chemical weapon:
Sometimes the cause of mydriasis (dilated pupils) can be hidden in acute poisoning of the body and its intoxication. And the development of dilated pupils is largely facilitated by the conditions of a professional activity related to the use of toxic chemicals.