Too much exposure to environmental manganese may up cancer mortality rates

Washington, July 11 : A Wake Forest University Baptist Medical Center researcher says that the presence of manganese in the environment can correlate with cancer mortality at any place.

Dr. John Spangler, a professor of Family and Community Medicine at Wake Forest Baptist, came to this conclusion following the observations made during an ecological study, the first of its kind in the world, which showed that groundwater and airborne manganese in North Carolina correlates with cancer mortality at the county level.

He says that groundwater manganese appears to be positively associated with total cancer, colon cancer and lung cancer death rates, while airborne manganese concentrations appear to be inversely associated with total cancer, breast cancer and lung cancer death rates.

"People need manganese in trace amounts, but if you get too much of it, manganese can be dangerous. It''s my hope that the impact of this study will be to spark additional interest and research. This really just raises the concern that something may be going on and argues for further research into these issues," Spangler said.

Using data from the North Carolina State Center for Health Statistics, North Carolina Geological Survey, U. S. Geological Survey, and U. S. Census for his ecological study, Spangler determined that airborne manganese was associated at the county level with an 14 percent decrease in total cancer deaths, a 43 percent decrease in breast cancer deaths and a 22 percent decrease in lung cancer deaths.

He also found that there was up to a 28 percent increase in county-level colon cancer deaths, and a 26 percent increase in lung cancer deaths at the county level related to elevation of manganese in groundwater as opposed to air.

"That''s pretty astounding. These are the first data we know of to document a potential relationship between environmental manganese and population-level cancer death rates," Spangler said.

"The positive association between groundwater manganese and specific cancer mortality rates might be a function of the high concentrations measures, while the inverse relationship between air manganese and death rates might point toward adequate (e. g. healthy) county-level manganese exposures," he added.

Given that manganese is gradually replacing lead in gasoline globally, Spangler reckons that its levels in the environment are increasing, and may worsen the groundwater concentration numbers in the future.

He says that the effects of these ecological findings should be confirmed at the individual level or in animal models.

A research article describing his study has been published in the online edition of the journal Biological Trace Element Research. (ANI)