Air Pollution Linked to Childhood Cancers
Children may be affected by the exposure of certain compounds in car exhaust even before birth.
Scientists said mothers who had a higher exposure to traffic pollution while pregnant were more likely to have children who developed cancers like acute lymphoblastic leukemia and a type of eye cancer, according to the American Association of Cancer Research in Washington, D.C..
The researchers studied 3,950 children born between 1998 and 2007 who were part of the California cancer registry. In order to assess traffic pollution, scientists estimated the amount of traffic within a 1,500 meter radius of each child's home during every trimester of the mother's pregnancy and for one year after the child was born. Factors like traffic volume, road geometry, emission rates and weather were all assessed to calculate the exposure to car pollutants from the first utero stage through the baby's first year of life.
The risk of a child developing certain cancers was greater with each increase of 53 parts per billion of carbon monoxide pollution, according to study author Julia Heck, of the department of epidemiology at the University of California Los Angeles' Jonsson Comprehensive Cancer Center. Each increase heightened the risk of developing retinoblastoma (an eye cancer) by 14 percent, and also increased the risk of cancer in organs such as ovaries and testicles by 17 percent, Heck told Bloomberg News.
Researchers established that the pollution had a high correlation with increased cancer risk across each trimester and during the first year of a child's life. However they were unable to determine during which period of development the exposure to pollution created the most harm.
"Much less is known about exposure to pollution and childhood cancer than adult cancers," Heck said in a statement. "Our innovation in this study was looking at other more rare types of childhood cancer, such as retinoblastoma, and their possible connection to traffic-related air pollution."
Previous studies have linked pollution exposure to polycyclic aromatic hydrocarbons (PAHs) found in cigarette smoke and car exhaust during pregnancy, to obesity in children later on. Other studies have also tied pollution exposure to behavioral problems in children.
The latest findings give researchers reason to further investigate the potential risks of traffic pollution. While it is difficult to avoid air pollution, especially in urban areas, pregnant woman should try to limit their exposure to factors that can contribute to childhood cancer, such as smoking.
This article was adapted from Time Health.