A group of Japanese researchers said they have recorded abnormalities in electrocardiograms and increased incidents of miscarriages in mice that breathed in harmful particles present in diesel-fuel exhaust fumes.

The results of the research, which were revealed Friday, come as the government is trying to devise measures to reduce diesel emissions.

Conducted by researchers from the National Institute for Environmental Studies, the University of Tokyo and the Tokyo University of Agriculture and Technology, the study's results will be reported at a meeting of the Japan Society of Atmospheric Environment that begins Wednesday in Urawa, Saitama Prefecture.

The findings will also be discussed at a conference of the Japan Society of Veterinary Science in Osaka Prefecture, held from Oct. 7 to Oct. 9. The team recorded the ECGs of a group of mice that breathed DEP air for nine months, 12 hours a day.

Among 15 mice that breathed the dirty air, abnormal ECGs were recorded in four, compared with only one in 15 mice that breathed clean air.

The team also had the mice breathe DEP air for a year. Seven out of 15 that lived in air with 0.3 mg of DEPs per cubic meter of air had abnormal ECGs, as did nine mice out of 15 in environments with 3 mg of DEPs per cubic meter.

The team mated female mice that had breathed DEP air for three and half months with males that had breathed clean air. The experiment resulted in an increase in miscarriages and offspring deaths during birth.

Increased incidence of miscarriage and newborn deaths also occurred when females that had breathed clean air were mated with males from DEP environments.

U.S. research has suggested that people who live in areas with high densities of airborne particulate matter, much of which is DEPs, have a greater chance of dying from heart disease.