Well, it seems that you care a lot about your eyes. So, as a matter of fact, reading in dark environment would inevitable harm our eyes to some extent, and we could easily go tired before long. However, even if we try to read in a dark environment, we would simply not go blind, since our vision is not that fragile. But it would cause dramatic drop in your vision and eye health. So, please try to avoid reading in a dark environment.
Reading in low light doesn't damage your eyes, but it can easily cause eye strain, which including sore eyeballs, headaches, back and neck aches and blurred vision. But if you are comfortable reading in the dark and do not experienced any of the above symptoms of eye strain, it might be fine for you reading in this way.
The possibility of reading in the dark to cause blindness is so small. However, there still exists the possibility. Reading in the dark will make your eye vision get weak. At the same time, your eye nerves will be broken. Once your eye nerves are damaged to death, your eyes may get blind. You'd better not read in the dark which will be bad for your eye vision.