This is the VOA Special English SCIENCE REPORT.
American scientists have found that the chemical D-D-T increases the risk of pregnant women giving birth too soon. They say the use of D-D-T in the United States may have caused many premature births during the Nineteen-Sixties. Premature births can cause health problems in babies and increase the risk of death.
D-D-T is a chemical used to kill insects. The United States banned it in Nineteen-Seventy-Two because of its unknown health effects on people. Other industrial countries have also restricted or banned the chemical. But it is still used in many developing countries to control mosquitoes that carry the disease malaria. Malaria affects as many as five-hundred-million people around the world each year. D-D-T is said to be effective in controlling the disease.
D-D-T is part of the World Health Organization’s program to end malaria in twenty-five countries. So there are concerns about its effects in those countries.
Scientists have long suspected a link between premature births and D-D-T. But evidence from earlier studies was not strong.
The new study was carried out by three federal health agencies and the University of North Carolina. Researchers studied blood samples from almost two-thousand-four-hundred American women who had babies between Nineteen-Fifty-Nine and Nineteen-Sixty-Six.
D-D-T is a compound of several chemicals and agents. One chemical remains in human tissue after many years. It is called D-D-E. Researchers tested the blood samples for levels of D-D-E.
Among the mothers studied, more than five-hundred-eighty babies were either born premature or weighed less than most babies. The mothers of these babies had higher levels of D-D-E in their blood. Scientists say that these women were exposed to higher levels of D-D-T in the environment. Some researchers say other chemicals that are less harmful than D-D-T can be used to control malaria. But other experts say no other pesticides are as effective and cost as little. They say banning its use now would be harmful to developing countries where malaria is widespread.
Experts say D-D-T could be restricted under a United Nations treaty on harmful chemicals if more evidence is found that it is dangerous to people.
This VOA Special English SCIENCE REPORT was written by Cynthia Kirk.