EPA’s Analysis of Florida Drywall Samples and Review of Analytical Results from the Florida Department of Health
The U.S. Environmental Protection Agency's assessment supports the test results reported by the Florida Department of Health on the Florida drywall samples. The EPA measurements confirm that these drywall samples contain only background concentrations of naturally-occurring radionuclides. Phosphogypsum contamination is not indicated.
In particular, the levels of radium-226 found in these samples were generally more than a factor of 10 lower than those found in phosphogypsum (10 to 35 pCi/g), but comparable to levels found in other commonly used building materials, such as brick or concrete. Thus, within the limited sample of drywall assayed, there does not appear to be any radiological concern.
Sample Receipt and Login
The EPA National Air and Radiation Environmental Laboratory (NAREL) received 21 drywall samples from the Florida Department of Health (FDOH), Bureau of Radiation Control on July 23, 2009, at 8:50 AM. The samples were received in good condition with no visible damage to the shipping box. After completing all safety and contamination checks, the samples were removed from the shipping box. Two portions for each sample were received: (1) prepared sample in a plastic container for gamma analysis (approximately 200-400 g); (2) remaining sample as an unprepared 6” x 12” block of drywall.
The sample IDs on the containers were compared to the sample IDs on the letter and spreadsheet report received with the samples, and there were no discrepancies. The NAREL Sample Prep Lab staff verified the weights of the sample portions prepared for gamma analysis, and then transferred the samples to the Counting Room. The remaining portion of each sample was retained in the Sample Prep Lab.
The following table contains a reference between the NAREL sample number and the sample identifications provided by the client.
A9.06050X-1 & 2
A9.06051Y-1 & 2
A9.06052Z-1 & 2
A9.06053A-1 & 2
A9.06054B-1 & 2
A9.06055C-1 & 2
A9.06056D-1 & 2
NAREL Sample No.
FDOH ID#/ CPSC ID#