Genuine question. Wouldn't it be more efficient to check the levels of lead in the people periodically? If a sparrow has high levels of lead then you still ne

Genuine question. Wouldn't it be more efficient to check the levels of lead in the people periodically? If a sparrow has high levels of lead then you still need to check the people. It seems like it would be fewer steps, fewer tests, and less messing around by making testing more available to the people.