Joint Base Langley–Eustis (JBLE) Environmental Management Awareness and Competency (EMAC) Practice Exam 2026 - Free EMAC Practice Questions and Study Guide

Hazardous materials in e-waste are often heavy metals that can leach into soil and water and cause serious health and environmental risks. Lead, mercury, chromium, cadmium, and beryllium are well-known examples found in various electronic components—lead in solder and CRT glass, mercury in switches and backlighting, cadmium in batteries and coatings, chromium in coatings and alloys, and beryllium in certain springs and connectors. These substances are the ones most commonly associated with the hazardous profile of electronic waste and require special handling and recycling to prevent exposure. The other options list substances that aren’t the typical hazardous metals tied to e-waste: ammonia and chlorine are more about cleaning or refrigerants, sodium and potassium are reactive alkali metals not usually present as e-waste hazards, and oxygen and nitrogen are merely common atmospheric components.