CDPH Lead Inspector/Assessor California State Practice Exam

What unit of measurement is used for lead in soil?

1. Micrograms per square foot (μg/f2)

2. Milligrams per kilograms (mg/Kg)

3. Parts per billion (ppb)

4. Milligrams per square meter (mg/m2)

The correct answer is: Milligrams per kilograms (mg/Kg)

The unit of measurement that is most commonly used for lead in soil is milligrams per kilogram (mg/Kg). This measurement indicates the concentration of lead present in a given mass of soil, providing a clear understanding of lead contamination levels. Using mg/Kg allows for consistent comparison since it reflects the weight of lead relative to the weight of soil, which is important for assessing health risks related to soil contamination. While other options like micrograms per square foot and parts per billion are relevant in different contexts, they are not standard for reporting lead levels in soil. For instance, parts per billion is often used in water quality assessments, while milligrams per square meter pertains to surface area contexts, which do not apply as effectively to measuring soil contamination. Therefore, mg/Kg is the most appropriate and standard measurement in the context of lead concentration in soil.