This was the conclusion of a final study by the Philippine Nuclear Research Institute (PNRI) which utilized state-of-the-art equipment, including a rare device that was used to determine the extent of the world’s worst nuclear accident in Chernobyl in 1986.
Teofilo Garcia, PNRI senior science specialist, told local reporters in a briefing that vegetable, soil and water samples tested had lead content way below the average tolerable limits.
He said another study done at the former US naval base in Subic also yielded negative results on radioactivity.
Garcia said the latest PNRI study covered the former ammunition dumpsite of the US Air Force here, which the Clark Development Corp. (CDC) initially feared could be the most probable contaminated site in the ecozone.
In its latest study completed last month, the PNRI used an instrument called the gamma ray spectrometer which Garcia said is one of the few existing equipment of its kind in the world.
He said the Vienna, Austria-based International Atomic Energy Agency donated the equipment, which is known to be quite sensitive and capable of distinguishing between natural and man-made radionuclides.
"The same instrument was used in the Chernobyl accident in Ukraine in the former USSR (Union of Soviet Socialist Republics) in 1986," Garcia said.
The PNRI used it to detect traces of Cesium-137, a man-made form of radioactive gamma ray.
Tests revealed that soil samples had only 0.98 to 4.64 becquerel or bq. (unit of measurement for gamma ray) per kilogram, while vegetable samples from a 10-hectare farm in the ecozone had 0.07 to 1.34 bq. per kilogram. These were way below the national Cesium-137 average range of .09 to 12.77 bq. per kilogram for soil and 0.7 to 1.33 bq. per kilogram for plants.
Using standards of the Bureau of Soils and Water Management, the PNRI also measured lead levels and concluded that soil and vegetable samples from the control site here were safe from lead.
"Results of the analysis are within background values and thus, do not pose any hazard to public health," Garcia said.
Garcia recalled that the PNRI conducted two other studies on radioactivity here in 1997 and 1998, virtually covering the entire 4,500-hectare ecozone.
Both studies also revealed no radioactive danger in any part of the ecozone.
In these studies, the PNRI used a mobile gamma ray spectrometer to detect any radioactive elements in the air as well as in water from wells.
The studies covered three former US military landfills, two igloo armories, an abandoned military hospital, two incinerators, the Mimosa resort and the Philippine Air Force housing areas, the Heroes cemetery, the former motorpool area, the CDC’s main office area, the firing range and the road networks.