On the other hand, there are other radioactive elements -- plutonium, uranium, and neptunium -- that are harmful and concern those government officials in charge of guarding public health. If ingested or inhaled, these radioactive materials can penetrate internal tissues and become a health hazard. Moreover, external doses can cause burns to the skin, or worse. As the first line of defense at our nation's borders, Customs is responsible for denying entry to hazardous, radioactive substances and for ferreting out the smugglers and terrorists whose plan is to introduce these deadly substances into our communities.

Earlier this year, at the Olympics in Salt Lake City, Laboratories and Scientific Services (LSS) and the Office of Field Operations worked side-by-side with non-intrusive detection equipment to ensure the safety and security of spectators and participants. The concept of Operation Guardian grew from this positive working relationship.

Operation Guardian is a joint program with the Office of Field Operations that gives LSS scientists an opportunity to utilize their detection equipment at the U.S. borders to assist Customs inspectors in identifying instruments of terror that could be smuggled into the United States. This operation allows LSS scientists to use trace detection equipment to screen mail parcels, sea containers, and air cargo for explosives and chemical, biological, and nuclear materials.

Photo Credit: Aaron Diaz

At the port of Miami, Chemist Charles Rawlinson screens a sea container for radiation using an isotope identifyer

LSS scientists bring high-tech instruments with them when they travel to Operation Guardian assignments. These tools can be easily transported to a specific location of interest in a very short period of time. The isotope identifier not only detects the level of radiation, but also identifies the specific radioisotope. This isotope identification is essential because the information can be used to discriminate between safe and legal radiation sources, such as nuclear medicines, and potential nuclear materials that could be used in "dirty bombs."

Additionally, LSS scientists use other scientific gear that detects trace amounts of dangerous materials by extracting an air sample or by analyzing the surface of a suspect article.

Using this technology, LSS can rapidly and accurately determine whether the article of interest contains dangerous chemicals, narcotics, or explosive materials.

Through Operation Guardian, LSS scientists were able to use their detection gear to analyze, and ultimately discount, the presence of explosive materials in a suspect sea container in Newark, and, in addition, discover a parcel containing radioactive material in Miami.

In November, LSS scientists traveled to six U.S. airports screening air cargo and passenger luggage.

When a radiation source and threat are identified, Customs officers should contact the nationwide response team for further information and technical advice. Members of the response team can be reached 24 hours a day, seven days a week at (407) 975-1780.