According to a first-time standardized international study led by a team including an Indiana-based researcher exposure to trace metal found in household dust could affect human health.

The study, also known as the DustSafe program, had people from 35 countries vacuum their homes and send their dust to universities in the U.S., the U.K., Australia and Hong Kong, where it was tested for possible toxic trace metals. The goal was to determine the source of the trace metals and the home residential environment conditions associated with increased exposure risk.

Gabe Filipelli, professor of earth sciences at Indiana University-Purdue University Indianapolis and executive director of IU’s Environmental Resilience Institute, led the U.S. arm of the project.

The researchers tested dust for arsenic, copper, chromium, manganese, nickel, lead and zinc.

They found that sources of contaminants included soil that gets tracked in by shoes, lead from emissions and paints, and building materials in older homes.

They also found that exposure to contaminants through dust affects all people, no matter where they live, but local environmental factors and contamination histories can make a difference.

Communities can be affected by mining and smelting activities, which can cause high lead levels. Additionally, inner city areas can be affected by emission sources and peeling paint.

Although most global averages of trace metals were within the acceptable range, some homes exceeded the normal range. Household dust in Australia was found to have lead-related risks and in the US chromium-related risks were found.

Homes constructed with metal had the highest concentration of manganese, which is an additive to steel. Metal, asbestos and timber homes had higher concentrations of lead, likely due to paints or wood treatment. Wooden floors were also linked to higher concentrations of arsenic and lead.

The research also showed that older homes had higher levels of all metals except for chromium, and these homes are likely to have residues from traffic and industrial pollutants, peeling paints, pest treatments and other chemicals.

Additionally, the study found arsenic concentrations to be 19% higher in recently renovated homes.

Homes associated with crafts such as jewelry making, woodwork, modeling and mineral collection were linked to higher lead concentrations.

Exposure to trace metal has been associated with health impacts such as obesity, hypertension and type-2 diabetes and may be significant in the development of Parkinson’s disease.

Data from the study is available here.