Basophilic stippling of red blood cells can indicate exposure to which of the following?

Basophilic stippling of red blood cells is a microscopic finding that indicates the presence of ribosomal RNA in the red blood cells, which is typically associated with certain types of toxicity or metabolic disturbances. Lead poisoning is the most classic condition in which basophilic stippling occurs.

When lead interferes with heme synthesis, it causes disturbances in erythropoiesis, leading to the retention of ribosomal RNA and resultant stippling. This finding is an important marker for diagnosing lead poisoning, as these stippled red blood cells can often be seen in a peripheral blood smear of affected individuals.

In contrast, while other conditions like iron deficiency anemia and sickle cell disease can produce distinctive changes in red blood cell morphology (such as microcytic anemia in iron deficiency and sickle-shaped cells in sickle cell disease), they do not typically show basophilic stippling. Therefore, when assessing for exposure to lead, the presence of basophilic stippling serves as a strong indicator of lead toxicity.