Placing the laptop on the lap for long hours is not ggood for the skin and can lead to a condition known as 'toasted skin syndrome'.
A study published in the journal Pediatrics says that placing the laptop next to skin for long periods of time can lead to "toasted skin syndrome," an unusual-looking mottled skin condition caused by long-term heat exposure.
It has been said that the condition could be caused by overuse of heating pads and other heat sources that usually aren't hot enough to cause burns.While it is harmless, it can lead to permanent skin darkening. In rare cases, this condition could cause damage leading to skin cancers.
Well, it is better to place a carrying case or other heat shield under the laptop when holding the laptop in your lap.