Concentrations of Manganese in Tufted Titmouse Feathers near Metal Processing Plants.

Simple Summary: Steel production emits manganese and other heavy metals into the environment, where these byproducts can lead to health problems in humans and other animals. Birds have historically been used to detect harmful chemicals in the air, and in this paper, we show that this role continues into the present day. Feathers of a small terrestrial songbird, the Tufted Titmouse, were collected from live birds captured both near (0.3 km) and far (4.0 km) from steel production facilities in western Pennsylvania, USA. Tail feathers from birds living near the facilities had significantly higher amounts of manganese embedded in their structure compared to the feathers of birds living farther away. This shows that manganese is present in the environment, is localized at industrial sites, is encountered by birds, and is sequestered in their tissues. Animals could suffer ill health if exposures are high enough. Feather data cannot be used to assess the magnitude of this health risk since metals laid down within feathers are no longer circulating in the birds' bodies. However, our data do suggest that the environmental monitoring of manganese should continue, as inadvertent exposure is still occurring. Human industry and land use has led to the anthropogenic release of manganese (Mn) into the air and soil near manufacturing centers. Overexposure to Mn can cause considerable health problems in birds. We studied whether the concentration of Mn in bird feathers correlates with the distance to point sources of Mn air emissions. Feathers were collected from Tufted Titmice (Baeolophus bicolor) at two sites in western Pennsylvania, USA. One site was in proximity (0.3 km) to a steel plant with documented Mn releases, and the other site was in a different town about 4.0 km away from other steel plants with documented Mn releases. Using the microwave plasma–atomic emission spectrometer (MP–AES), we found that tail feathers collected from nearest to a steel plant had a significantly higher concentration of Mn compared to the samples from the site further from the emission source. A body mass index was calculated for each set of birds; however, the indices did not vary significantly. This is the first published study of Mn sequestration in Tufted Titmouse feathers. This study develops our general understanding of the potential use of bird feathers as non-invasive bioindicators of environmental metal exposure. [ABSTRACT FROM AUTHOR]