Despite nationwide remediation efforts, lead poisoning still poses a significant public health problem. Recent data indicates that nearly 1.5 million preschool children have lead in their blood at nearly two times the upper limit recommended by Environmental Protection Agency and the Centers for Disease Control. Children may come in contact with lead in the soil, paint, water and food. Traditional methods are not sensitive enough to allow detection of lead amounts in the blood at new federally mandated levels and major efforts to increase the conventional technology's sensitivity have fallen short of expectations, Los Alamos researchers say. To achieve increased sensitivity in a reliable, economically feasible system, Los Alamos researchers have developed a selective laser technology known as resonant laser ablation and combined it with mass spectrometry to measure lead in environmental and biomedical samples.
Laser ablation uses short pulses of high peak power to rapidly heat and vaporize a sample.
Coupled with a mass spectrometer that measures the resultant molecular ionization, the new technology offers quick, noninvasive sample analysis in the parts per billion range, much more sensitive than the federal agencies require. The emergency response team needs to calculate a range of risk factors, including how the toxic plume may disperse and what potential dose and toxic concentrations might be expected. A new software program running on a hand-held calculator provides the answers. The program, called GAUS1, analyzes how plumes of gases and particles disperse in the atmosphere, settle on the ground and get lifted back into the air under different weather conditions. GAUS1 includes more parameters for meteorological and source conditions than are available with mainstream computing systems.