Date of Award

Spring 2016

Project Type


Program or Major


Degree Name

Master of Science

First Advisor

Sterling A Tomellini

Second Advisor

Howard Mayne

Third Advisor

W. Rudolf Seitz


Quantitation of total mercury has been of great interest not only in environmental fields, but also in medical research. This is because mercury (Hg) is one of the most toxic elements, and is also a well–known global pollutant. Researchers strive to understand how toxic elements bioaccumulate in both aquatic ecosystems and terrestrial systems, along with these effect on human health. Numerous studies and analytical methods have been published for the assessment of mercury in many different sample matrices. Accurate analysis of these complex matrices is dependent on accurate and reliable analytical standards. However, the standards preparation step is time consuming. This stability study is to extend the storage lifetime of the mercury intermediate standards, provide high recoveries, and minimize the mercury memory effect which will improve the applicability of biomonitoring studies for human health risk assessment related to mercury exposure. This approach can save time, and reduce cost if the storage lifetime of the standards can be sufficiently predicted. Three preservative solution combinations were investigated: 1% (v/v) nitric acid with 1% (v/v) sulfamic acid and 1% hydrochloric acid; 2% (v/v) nitric acid with 1% (v/v) sulfamic acid; and 5% (v/v) nitric acid with 1% (v/v) sulfamic acid. Standards were stored in sealed polypropylene containers at 3 temperatures (-28°C, 1°C, and room temperature). The use of 1% (v/v) nitric acid, 1% (v/v) sulfamic acid preservative solution, and 1% (v/v) hydrochloric acid in mercury intermediate standards stored in the refrigerator provided the best performance for up to 90 days. The results were in good agreement with the certified quality control values.