The photo taken on Sunday shows the terrible air condition in Beijing. (Photo source: CNS)

(ECNS) �C A new study conducted by a Tsinghua University research team has detected more than 1,300 species of microbes in Beijing smog, the Legal Evening News reported.

Most of the microbes are harmless and common in soil and water, but a smaller number of bacteria might cause allergies or respiratory diseases, it said.

Whether the "harmful" microbes are alive or dead or if a low proportion could affect human health remains to be seen, according to the research.

Zhu Ting, a researcher with the team, said the air samples they tested were taken in January 2013.

Zhu and his team used genome analysis on the smog samples. "In this way we can figure out which species are harmful and which are not."

Zhu said it's the first analysis in the world of microbes in air at the species level. "We have published the study methods and released the research data for further study," he said.

The study was published in "Environmental Science & Technology" in January 2014.