Children studying in East Liverpool,Ohio, who are exposed to higher levels of Manganese (Mn), had scored lower in IQ tests, found environmental health researchers at the University of Cincinnati (UC) Collage of Medicine.
The team of researchers studied blood and hair samples of 106 children who are aged between 7 and 9, from East Liverpool and other neighboring communities, who were enrolled in the study . It found that higher level of Mn in hair samples was mainly associated with considerable decrease in IQ levels, processing speed and memory power.
Manganese is a chemical element with an atomic number 25, and is often found in minerals in combination with iron. It has a major role in brain growth and development. However, if expose excessively may lead to result in neurotoxicity. Manganese is widely used in the production of steels, batteries, and fertilizers.
Erin Haynes, the lead author of the study, took up the study when he was approached by some officials from East Liverpool school districts in 2013 which witnessed lower academic performance by their students. Another reason for the study was the local knowledge that Mn concentrations in the area are high. The Mn concentrations in the East Liverpool school have surpassed the levels prescribed by US Environmental Protection Agency (EPA) for over a decade.
"There are socio-economic issues at play, however, they are also compounded by potentially significant environmental exposures," said Haynes. "Children may be particularly susceptible to the neuro-toxic effects of ambient Mn exposure, as their brains are undergoing a dynamic process of growth and development," he explained.
The students were also put to neuro-psychological test. Haynes and his team found the levels of Mn in children were double and further investigation was taken up study the link between Mn exposure and child cognition abilities.
Marietta , Ohio, was the original location of the Communities Activity Researching Exposture Study (CARES) which was started in 2008 on community concern about exposture to mangnaese from nearby metallurgical manufacturing company. "Mariette and East Liverpool have higher levesl of ambients Mn in the country," said Haynes.