What is the measure used for lead concentration in the soil?

The measure used for lead concentration in the soil is generally expressed in micrograms per parts per million (ppm), which indicates how much lead is present in a given mass of soil. This measurement is particularly relevant for soil analysis because it provides a clear indication of contaminant levels in relation to the total weight of the soil sample.

Parts per million is a common unit in environmental science, allowing for easy assessment of how contaminants like lead can potentially affect human health and the ecosystem. This unit reflects not only the concentration of the lead but also helps in understanding its potential impact, as lower concentrations may still represent significant environmental or health concerns depending on the context.

The other measurement options, while relevant in various contexts (such as milligrams per liter for water or micrograms per cubic meter for air quality), do not accurately describe soil lead concentration. Milliliters per gram is not a standard unit for measuring concentrations and would be unsuitable in this context.