Which naturally occurring mineral is known to be toxic and has been used in paint and plumbing?

Lead is the naturally occurring mineral recognized for its toxicity, particularly in contexts related to paint and plumbing. Historically, lead was commonly used in paints due to its properties that enhance color and durability. However, it was later discovered that lead exposure can lead to severe health issues, including neurological impairments, especially in children.

In plumbing, lead was prevalent in pipes and fittings because of its malleability and resistance to corrosion. Despite its advantages, the toxic effects of lead when it leaches into drinking water have prompted significant regulations and initiatives to replace lead plumbing systems in many areas to protect public health.

The other substances mentioned are significant in their own right but do not share the exact same history of widespread use in paint and plumbing that would classify them as the answer to this particular question.