What is the ruling on eating foods harmful to health, such as chips and soft drinks? Is a person sinful for doing so? Is using sanitary pads forbidden because they pollute the environment? And must a person who suffers from urinary incontinence perform istinja' for every prayer, or only wudu'?

Soft drinks and chips are permissible unless their harm is proven. If their harm is proven and a person insists on consuming them, then he is sinful. Sanitary pads are permissible and not forbidden on the grounds of polluting the environment. The proof for this is what Abu Dawud and Al-Tirmidhi narrated from Abu Sa'id Al-Khudri that the Messenger was asked about a well into which menstrual cloths, dog meat, and putrid things were thrown. He said: "Indeed, water is pure; nothing makes it impure." A person afflicted with incontinence must perform ablution (istinja') before every prayer, unless the incontinence stops.