Environmental Protection Agency (EPA) Lead Risk Assessor Practice Exam

What are the first organs to be affected by lead ingestion?

1. The heart and liver

2. The lungs and kidneys

3. The digestive system

4. The nervous system

The correct answer is: The nervous system

Lead ingestion primarily affects the nervous system, particularly in young children, who are at the greatest risk due to their developing brains and nervous systems. Lead can disrupt normal neurological function, leading to a range of adverse effects, including cognitive deficits, behavioral issues, and in severe cases, encephalopathy. This susceptibility occurs because lead can disrupt neurotransmitter systems, interfere with calcium metabolism, and affect neurodevelopment during critical growth periods. While other organs such as the digestive system, kidneys, and heart may also be affected by lead exposure, the nervous system is the most critical and vulnerable during the initial phase of lead ingestion, especially in children. Research has shown that even low levels of lead exposure can have significant detrimental effects on an individual's neurodevelopment, making this organ system the primary concern for health professionals assessing lead risks.