Where does approximately 90% of inorganic lead accumulate in the body?

Inorganic lead primarily accumulates in the bone, where approximately 90% of it is found. This accumulation occurs because lead has a strong affinity for skeletal tissue, which serves as a reservoir for the metal. When lead is ingested or inhaled, it enters the bloodstream and gradually deposits in the bones, where it can remain for long periods, potentially causing long-term health issues. This process can lead to chronic exposure effects, even after initial exposure has ceased, as lead can persist in the bones and be released back into circulation during periods of physiological stress, such as pregnancy or osteoporosis.

Other options might involve some lead accumulation, but they represent far less significant sites. The liver and spleen are involved in the metabolism and filtration of various substances, including toxins, but they do not hold the majority of the body's lead burden. White blood cells might also contain trace amounts of lead as they participate in systemic responses, but again, they do not accumulate lead to the extent that bones do. Thus, when assessing lead accumulation in the body, bone is the most relevant and critical factor.