Investigators and Program Directors

Research Interests

The primary focus of our research is the chemical characterization of trace elements in biological tissues and fluids. Such studies are important for understanding the biochemical role of essential trace elements, and monitoring human exposure to toxic elements such as lead.

Lead is a non-essential, toxic element that adversely affects the neurological development of young children. Measurement of lead in blood is normally used to assess exposure, with graphite furnace atomic absorption spectrometry (GFAAS) the most common analytical method. Once absorbed into the body, lead accumulates in bone where the residence time can be decades. Little is known about the localization of lead in bone or its mode of chemical binding. We are currently assessing the chemical and physiologic distribution of lead in human tibiae and in bones obtained from lead-dosed animals. We have characterized the lead content of these bones using GFAAS equipped with Zeeman background correction. Much of our analytical work requires an understanding of spectroscopy behind the measurement. Our more recent work has focused on producing a set of well-characterized bone lead reference materials that can be used to validate non-invasive in vivo X-ray fluorescence (XRF) techniques for bone lead. To accomplish this goal, we are collaborating with the XRF group located at the Mt. Sinai School of Medicine in New York on arranging interlaboratory studies for bone lead measurements using K-shell XRF techniques.

Aluminum is another non-essential element that also accumulates in bone and is neurotoxic. Although not a major concern for normal healthy individuals, it is a major problem for patients on hemodialysis and others with impaired renal function. Our laboratory has developed analytical methods for measuring traces of Al in bone and serum samples with the goal of characterizing its distribution and mode of chemical binding.

In addition to several Zeeman GFAAS instruments, we also have two inductively coupled plasma-mass spectrometers (ICP-MS) capable of measuring the stable isotopes of more than 70 elements, many at parts-per-trillion levels. This state-of-the-art instrumentation is equipped with Dynamic Reaction Cell (DRC) technology that can be used to achieve high accuracy measurements of trace elements in human body fluids. Our initial efforts have focused on measuring arsenic, mercury, cadmium and lead in whole blood; arsenic, mercury, cadmium, lead, barium, beryllium, cobalt, copper, manganese, molybdenum, antimony, thallium, zinc, and tungsten in urine; and selenium in serum matrices by ICP-MS to support a range of biomonitoring studies. Well-characterized blood, serum and urine reference materials have also been developed and certified for trace element content and these now form the basis of a trace elements proficiency testing program for clinical laboratories.

Contact Information

Phone: 518-474-5475
Fax: 518-473-7586
Fax: 518-473-2895 (alternate fax)
E-Mail: patrick.parsons@wadsworth.org.