Levels of radiofrequency (RF) electromagnetic fields emitted from an increasing number of mobile phone base stations in Bangkok and some other provinces are between 500 and 1,000 times lower than the harmful levels, according to the Department of Medical Sciences yesterday.
It was responding to inquires recently submitted by consumers who were worried about a rise in the number of mobile phone base stations, citing results of a survey conducted by the Bureau of Radiation and Medical Devices between fiscal year 2019 and 2020 in Bangkok, five surrounding provinces and 16 other provinces in the Central Plains region.
Department director-general Supakit Sirilak said the total number of base stations rose from 115,684 in 2017 to 170,577 in 2019, citing figures provided by the National Broadcasting and Telecommunications Commission.
The survey found that the levels of electromagnetic (EM) waves in frequencies between 950MHz and 2100MHz ranged from 0.000255–0.01776 watts per square metre, which is between 500 and 1,000 times lower than the maximum levels still considered safe under a standard set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP), Dr Supakit said.
According to the ICNIRP standard, EM waves emitted from 950MHz frequency base stations must not exceed 4.5W/m2, while ones emitted from 1800MHz and 2100MHz base stations must not exceed 9W/m2 and 10W/m2, respectively, he said.
People living near mobile phone base stations are therefore assured they are safe from any possible health risks of exposure to EM waves, Dr Supakit said.
The International Agency for Research on Cancer reportedly said RF electromagnetic fields are classified as possibly carcinogenic to humans (Group 2B), a category used when a causal association is considered credible, but when chance, bias or confounding cannot be ruled out with reasonable confidence, Dr Supakit said.
Pickled vegetables, gasoline and gasoline vapour are also in Group 2B, he said.
The director-general said the World Health Organization in 2018 confirmed that exposure to EM fields from the mobile phone system is not harmful to humans.
Although these readings of EM waves are considered safe levels, the bureau will continue monitoring and assessing their health risks, he said.