1.   After testing the substance, experts determined it was drywall material, authorities said.

2.   Glazier said that local officials had begun testing the substances and that so far all results had been negative.

3.   Gomez said the principal called HISD police, who had the substance tested.

4.   Hazmat officials responded and took the substance to be tested.

5.   It tests DNA as any substance would be tested for conductivity, by applying an electrical potential across it and seeing how much current flows.

6.   Now, the FBI is testing the substance to determine what it is.

7.   Police and medical officials quickly quarantined the office at the Hart Building, about a block northeast of the Capitol, while the substance was tested.

8.   State Health Commissioner Dr. Jan Carney said the substance was being tested out of an abundance of caution.

9.   The fFN Elisa tests a substance called fetal fibronectin to help determine whether a woman will give birth prematurely.