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Trace Elements in Abiotic and Biotic Environments
Technetium appears to have low chemical toxicity. No significant changes in the
blood and body were detected in rats, which ingested, for several weeks, food with
99 Tc content up to 15 mg/kg (Desmet and Myttenaere 2011).
The radiological toxicity of Tc (per unit of mass) is a function of compound,
type of radiation, and the isotope’s half-life. All isotopes of Tc must be handled
carefully. The most common isotope, 99 Tc, is a weak β emitter, and such radiation
is stopped by the walls of laboratory glassware. The primary hazard, when working with Tc, is inhalation of dust, resulted in lung contamination, which poses a
significant cancer risk.
Once in the human body, 99 Tc concentrates in the thyroid gland and the gastrointestinal tract. The body, however, constantly excretes 99 Tc, after it is ingested. The
Environmental Protection Agency (EPA 2002) has established a maximum contaminant level of 4 millirem per year, for β particle and photon radioactivity, from
man-made radionuclides in drinking water. As with any other radioactive materials, there is an increased chance that cancer or other adverse health effects may
result from the exposure to 99 Tc radiation, which is carcinogenic within Group 1
(IARC 2012b). 99 Technetium-m labeled human serum albumin (Tc-99m HSA) is
an important radiopharmaceutical for clinical applications, such as cardiac function tests or protein-losing gastroenteropathy assessment.
Trace Elements in Abiotic and Biotic Environments
Technetium appears to have low chemical toxicity. No significant changes in the
blood and body were detected in rats, which ingested, for several weeks, food with
99 Tc content up to 15 mg/kg (Desmet and Myttenaere 2011).
The radiological toxicity of Tc (per unit of mass) is a function of compound,
type of radiation, and the isotope’s half-life. All isotopes of Tc must be handled
carefully. The most common isotope, 99 Tc, is a weak β emitter, and such radiation
is stopped by the walls of laboratory glassware. The primary hazard, when working with Tc, is inhalation of dust, resulted in lung contamination, which poses a
significant cancer risk.
Once in the human body, 99 Tc concentrates in the thyroid gland and the gastrointestinal tract. The body, however, constantly excretes 99 Tc, after it is ingested. The
Environmental Protection Agency (EPA 2002) has established a maximum contaminant level of 4 millirem per year, for β particle and photon radioactivity, from
man-made radionuclides in drinking water. As with any other radioactive materials, there is an increased chance that cancer or other adverse health effects may
result from the exposure to 99 Tc radiation, which is carcinogenic within Group 1
(IARC 2012b). 99 Technetium-m labeled human serum albumin (Tc-99m HSA) is
an important radiopharmaceutical for clinical applications, such as cardiac function tests or protein-losing gastroenteropathy assessment.