Two recently released studies show that pollution affects fetuses. In April, the Journal of Epidemiology and Community Health published a study by the University of Medicine and Dentistry of New Jersey study. The study is based on nearly 336,000 births in New Jersey between 1999 and 2003 and regular monitoring of air pollution around the state
The study suggests traffic pollution and restricted fetal growth may be linked. There is a significant increase in chances of delivering a small weight baby every time pollution levels rise during the first three and third trimesters of pregnancy, according to the study.
In February, Chinese officials announced to state run media that birth defects are increasing and the major cause is pollution from coal. A by the National Population and Family Planning Commissions released in 2007 found birth defects increased almost 40 percent from 2001 to 2006, during the country's expansive economic growth.
Columbia University's Center for Children's Environmental Health released results of a six year study in the Chinese city, Chongqing last October that showed pollution from coal-fired plant affect birth weight, height, and motor development skills of babies born in area.
"The number of newborns with birth defects is constantly increasing in both urban and rural areas," Jiang Fan, vice minister of the National Population and Family Planning Commission said.
"It was clear that the pollutants caused damage to the DNA," said Tang Deliang, a co-author of the study.
Older studies showed similar results
In 2001, the American Journal of Epidemiology published a study by the UCLA School of Public Health and the California Birth Defects Monitoring Program (CBCMP). The research team looked at information on over 9,000 babies born from 1987 to 1993 in Los Angeles, Orange, San Bernardino, and Riverside counties from the CBCMP.
According to the team's research, women exposed to high ozone and carbon monoxide levels may be up to three times as likely to have baby with heart defects. The increased risk occurs during second month of pregnancy.
"The greater a woman's exposure to one of these two pollutants in the critical second month of pregnancy, the greater the chance that her child would have one of these serious cardiac birth defects," said Beate Ritz, a UCLA epidemiologist, who led the study.
"We're not sure carbon monoxide is the culprit because it could be just a marker for something else in tailpipe exhaust," said Gary Shaw of the CBCMP, who also worked on the research.
In 1990, the New York Times published an article about the Texas city of Pampa, and the high number of Down's Syndrome babies born there during the 1980s. The Texas Department of Health and the Federal Centers for Disease Control reported in 1986 that the Down's Syndrome rate in Pampa was "significantly more than expected."
A few years later, a lawyer who sued the Hoechst Celanese chemical plant for a 1987 explosion found evidence that the plant had toxins contaminating the region's main source of drinking water.
The prominent pediatrician, Dr. Gerald H. Holman, a former associate dean of the Texas Tech Medical School in Amarillo, released a report in 1990 that supported the lawyer's findings. The report said that "'in all medical probability" the high number of Down Syndrome births is "'is related to the environmental pollutants from the Celanese site."
The national rate of Down Syndrome births, according to the New York Times article, is one in 1,550 for very young women, and one in 1,000 for women in their late 20's and early 30's. The number of Down Syndrome births in Pampa, population 20,000, in the 1980s was 347 to 484 a year.
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