Method Detection Limit: refers to a minimum concentration of an analyte that can be measured above the instrument background noise.

Reporting Limit: the minimum level above which an analyte can be detected and quantified with statistical confidence.

Instrument background noise: Instruments have detectors that convert any target analyte entering the detector into an electrical signal that can be measured. Using a calibration curve, this signal can be converted into a concentration. Instrument noise is due to the normal, random generation of electrical signal from sources other than the target analyte. Some causes are radiation, magnetic fields, loose connections or static. They have nothing to do with the specific sample being analyzed.

MCL: The maximum concentration level or (MCL) is the maximum concentration of a chemical that is allowed in public drinking water systems. The MCL is established by the United States Environmental Protection Agency (EPA).

μg/L: The symbol μg = microgram. One microgram is one millionth of a gram and one thousandth of a milligram. So if the MCL reads 2 μg/L that is 2 micrograms per liter. It is also referred to as parts per billion (ppb). ‍

ND: not detected.