Mumbaikars have a reason to worry as the air they breath in is filled with heavy metals, an analysis conducted by the Brihanmumbai Municipal Corporation (BMC) has revealed.

The data gathered from the air quality monitoring and research laboratory between April 2010 and March 2011 reveal that levels of heavy metals like lead, iron, copper, cadmium, nickel and chromium have risen in one year.

According to a BMC official, though the rise is not alarming as such but has indicated that the quality of air is deteriorating in the megalopolis.

As per the analysis, the levels of iron have recorded a sharp rise at all seven air-monitoring stations--Borivli, Andheri, Khar, Deonar, Maravali, Bhandup and Worli from where the data has been collected.

The highest level of iron was recorded at Maravali in Chembur. In 2009, Maravali recorded 9.9 ?g/m3 (micrograms (one-millionth of a gram) per cubic meter air) of iron in the air and in 2010 this has shot up to 14 ?g/m3.

The presence of the metal has doubled from 0.57 ug/m3 in 2009 to 1.06 ug/m3 in 2010 in Andheri.

In some areas, there has been a marginal drop in the levels of metals. For instance, the levels of lead have dropped in Borivli and Deonar. Copper, too, has shown a dip in Worli and Bhandup.