Dust levels in the air in Bulgaria have remained above the norm throughout January, owing to the fog that has enveloped the country several times this month, the executive environmental agency said Tuesday.
From January 9 to 10, the levels of dust in the air in capital Sofia were four times the norm of 50 milligrammes of dust particles per cubic metre.
And in the second biggest city of Plovdiv, further south, dust pollution was six times the norm last week, reaching the highest levels in two years, data showed.
That has led to a two-fold increase in the number of patients being treated for breathing ailments over the past six weeks, Plovdiv hospital chief Goergy Blagoev told 24 Hours newspaper.
Authorities blamed the air pollution on thick fog that entraps dust emitted by industry, coal-fired heating plants and traffic.
Sofia is especially prone to fog as it is situated in a low field surrounded by mountains.
