The white spikes are the leaf "veins" that are a bit like a skeleton, but the rest of the leaf has not "fleshed"" out, hence why the veins/spikes stick out.
This happens from time to time for whatever reason and I find that the second set of leaves are usually fine, - if not, I toss them.
It is not a light or nutrien/pH problem, just a slight weirdo seed.
As we all know, not all seeds make it and not all seeds are perfect either.