Spider plant leaf
One of the spiderettes I have has a few leaves that turned all white. Is this cause for concern? What could be the reason for this?
As long as the leaf is healthy looking I wouldn't worry. If you plant is a variegated variety it is not uncommon to have some leaves that are all white or all green. There are lot of variegated plants that do this. It is just a sport or anomaly. The all with foliage doesn't photosynthesize light properly. If the majority of the plant produces predominantly all white foliage you might try cutting it back to encourage new growth from the base.
Your plant may be getting to much sunlight.
Here are some links with more information.