Environmental Protection Agency (EPA) Lead Risk Assessor Practice Exam

What is considered the strongest predictor for a child's blood lead level (BLL)?

1. Soil composition

2. Dust exposure

3. Water quality

4. Air pollution

The correct answer is: Dust exposure

Dust exposure is recognized as the strongest predictor for a child's blood lead level (BLL) due to its direct and frequent association with lead contamination in the home environment. Lead-based paints, which were commonly used in homes built before 1978, can degrade over time, creating lead dust that settles on surfaces and can be ingested or inhaled by young children. This is particularly concerning because children are more likely to put their hands, toys, or other objects that have come into contact with dust in their mouths. While soil composition, water quality, and air pollution can also contribute to lead exposure, they are generally less significant when it comes to the immediate and day-to-day risk a child faces within their home environment. Soil may contain lead from external sources, such as nearby industrial activity or deteriorating lead-based paint, but the exposure is typically lower and less frequent compared to the consistent presence of lead dust in homes. Water quality can be a factor, especially in older plumbing systems that may leach lead, but it usually provides a less immediate risk than dust. Air pollution containing lead is also a concern, but its impact tends to be less direct and not limited to the home compared to the occupational and recreational environments where children play and live. Thus