Ultra Carry

For many years now, environmental impact from designated hazardous elements such as Hg, Cr, As, Pb has been a concern. A method for analyzing these and other elements in water has been developed which allows a standard laboratory WDXRF system to attain PPB levels of detection.

Elements such as Cd, Pb, As, Cr and Se have been designated hazardous due to their potential environmental impact. Ecological concerns centering on these elements are due to contamination or poisoning of the flora and fauna through ground and river water.

Contaminates are introduced to lake and river waters, soils or into the water table through industrial waste, chemical pesticides, urban development, spills, etc. Contaminants also find their way into food supplies such as growing or grazing fields via irrigation or from rainfall. Monitoring of contaminate levels can be accomplished through direct plant analysis. This is basically after the fact testing. A more preventative method is through water supply analysis - detect elements of concern prior to plant contamination. The problem with this is that water testing requires many site samples to be taken. In view of this the test method needs to be fast, easy, safe and accurate. Also, working directly with sampled water needing no or little pretreatment would definitely be of benefit. XRF could be an ideal tool for this except for the low levels of determinations required and the concerns of working with liquids in an XRF system (support membrane ruptures).

Typical WDXRF lower limits of detections (LLD) for direct solution analysis are in the low ppm region at best. If a filter type paper is used for drying and concentrating the liquid then these LLDs may be reduced further to the sub ppm levels. This is still high for the required detection of these hazardous elements.

A solution to these many problems and concerns has been developed through a method using a product referred to as Ultra Carry. This method eliminates the liquid concern of support film breaking, achieves the required LLDs, plus no helium atmosphere is required due to dried samples being dried prior to analysis. An added benefit is that without the X-ray absorption of film support, analysis is possible for most elements from B to U.