The bracket on the left is stamped and lined with lead to shield from X-rays and gamma radiation. The replacement on the right has been injection molded of lead-free Trilliant HC PbF from PolyOne Corp. The tungsten-filled plastic performs as well or better than lead. Brass inserts also trim assembly time.

High-energy-electromagnetic radiation poses a great health hazard to those who must work around scanners, test and measurement instruments, fluoroscopes and X-ray machines, collimators, and other equipment. X-rays and gamma radiation are the most prevalent forms of this radiation.

Lead has traditionally been used to shield healthcare practitioners and patients from potential X-ray exposures. The material has been selected for shielding tasks for many years because of its physical properties, ease of casting and fabrication, and malleability.

Despite its usefulness, the U.S. Department of Health and Human Resources and the EPA have determined that lead is probably a human carcinogen and would like to see it replaced. Lead also ranks second on the U.S. Governments Hazardous Substances Priority List and the EPA has listed lead as a toxic chemical. Europe's RoHS Regulations also ban lead for certain electrical and electronic applications. Possible health complications from lead include behavioral problems, learning disabilities, seizures, and in extreme instances, even death.

The X-ray shield was injection molded with Trilliant HC PbF and shows detail that would otherwise be secondary manufacturing operations.

Fortunately, there are safe and effective alternatives to lead. The Specialty Engineered Materials Business Unit from our company has introduced Trilliant HC PbF (lead free) tungsten-filled plastic compounds for healthcare X-ray shielding. Tungsten has a density of 19.25 g/cc making it one of the densest naturally occurring elements. It is nontoxic and nonreactive and can be effectively blended with plastics in high concentrations (up to 90% by weight) to produce a compound with shielding attenuations equal to or better than lead. It has also been used in the healthcare industry for many years as a radiopacifier for catheters. It is safe, effective, and tried in the healthcare industry. Tungsten has been blended with PA11, and 12, PA12 based elastomers, PE, TPU, TPEs, and many other materials.

And because the material is injection moldable, it allows greater design flexibility through the consolidation of parts which reduces system costs. Further advantages come from using this environmentally friendly material because it is reusable and, unlike lead, can be disposed of through normal channels. In addition, parts made with Trilliant HC PbF are less prone to damage than lead versions thereby generating fewer service and field replacement issues.

Trilliant HC PbF and Trilliant HC are supported by the company's product stewardship program which includes facilities certification for Food, Drug & Medical Products Good Manufacturing Practices compliance by yearly audits, screening of raw materials for adherence to U.S. Pharmacopeia Class VI standards, random testing for heavy metals, and review of all new product formulations to determine compliance standards.