Iran's six saltmen, unique among the world's salt mummies, are endangered after delay in getting to their technologically advanced resting place.

A vacuum chamber in Zanjan was built to preserve the mummies in Iran. It precisely controls humidity and airflow and is provided with a nitrogen-rich mixture deadly to known bacteria and mold.

Iranian, British, German and Austrian researchers had declared that air and humidity are the main enemies of salt mummies.

Despite the positive measures taken for the preservation of the ancient mummies, the timing was askew. The mummies have not been transferred to their new resting place until now.

The tardiness of the measures led to some decomposition of the salt mummies in their nonstandard display cases.

The saltmen were accidentally uncovered by miners in 1993 in Chehrabad Salt Mine, located in the Hamzehlou region of Zanjan province in northwestern Iran.

Three of the saltmen date to the Parthian (247 BCE - 224 CE) and the Sassanid (224 - 651 CE) eras, while all other human remains discovered at the site go back to the Achaemenid Dynasty (550 - 330 BCE).

Salt at the mine preserved the artifacts, as well as the internal organs of the salt men themselves. Fingernails and hair have been found undamaged, which will enable testing to be carried out that could reveal further clues about these ancient individuals.

NAT/JG