Which compound of lead found in old manuscripts poses the greatest health risk?

The compound of lead found in old manuscripts that poses the greatest health risk is Lead carbonate (white lead).

- Lead carbonate, commonly known as white lead, was historically used as a pigment in paints and inks found in old manuscripts.
- This compound is highly toxic due to its solubility in acidic environments, such as the human stomach, which facilitates the release of lead ions into the body.
- Once absorbed, lead interferes with multiple physiological systems including the nervous, hematopoietic, and renal systems.

- Unlike lead sulfide, which is relatively insoluble and less bioavailable, lead carbonate readily dissolves, making it more easily absorbed through ingestion or inhalation of dust particles.
- Similarly, lead oxide and lead phosphate have lower solubility and bioavailability compared to lead carbonate.

- The chronic exposure to lead carbonate can lead to lead poisoning (plumbism), with symptoms ranging from abdominal pain, anemia, and nephropathy to severe neurological impairments, especially in children.

Key points:
- Lead carbonate (white lead) is commonly found in old manuscripts as a pigment.
- It has high solubility and bioavailability, making it the most hazardous lead compound in this context.
- Exposure can cause serious systemic toxicity, particularly affecting the nervous system.
- Other lead compounds such as lead sulfide, lead oxide, and lead phosphate are less soluble and pose lower health risks.

Reference: Harrison’s Principles of Internal Medicine, 20th Edition, Volume 2, Chapter 69: Heavy Metal Poisoning / Lead Toxicity