## trace element

https://doi.org/10.1351/goldbook.T06421
Any element having an average concentration of less than about 100 parts per million atoms ($$\text{ppma}$$) or less than $$100\ \frac{\unicode[Times]{x3BC}\text{g}}{\text{g}}$$.
Source:
PAC, 1979, 51, 2243. (General aspects of trace analytical methods—IV. Recommendations for nomenclature, standard procedures and reporting of experimental data for surface analysis techniques) on page 2246 [Terms] [Paper]