Associated Press, January 20, 2007

STUDY LINKS CHILD CANCER, AIR POLLUTION

[Rachel's introduction: A study finds that children living within 2 miles of the Houston [Tex.] Ship Channel had a 56 percent higher risk of getting acute lymphocytic leukemia than children living more than 10 miles from the channel.]

HOUSTON -- A new study links the risk of cancer in children with hazardous air pollutants (HAPs).

About The Study Executive Summary Full Study PDF

Hazardous Air Pollutants (HAPs) are a class of 189 chemicals which are known or suspected to have adverse effects on health, according to the Houston [Texas] Health Department. The Health Department reported that there are no national standards regulating acceptable levels of these compounds in the environment.

The study found that cancer risks are greater for children who live close to the Houston Ship Channel and adjacent industrial plants.

The 18-month study examined Harris County, Texas, cancer cases from 1995 to 2003 and emissions including 1,3-butadiene and benzene. It's the first study to identify a possible link between cancer risks and toxic air pollution in Harris County.

The study was conducted by the University of Texas School of Public Health. It was funded by the Houston Department of Health and Human Services and the Centers for Disease Control.

The study found that children living within 2 miles of the Ship Channel had a 56 percent higher risk of getting acute lymphocytic leukemia than children living more than 10 miles from the channel.

It also found that compared with children living in areas with the lowest estimated 1,3-butadiene levels, children living in areas with the highest levels had a 40 percent, 38 percent and 153 percent increased risk of developing any type of leukemia, acute lymphocytic leukemia and acute myeloid leukemia, respectively.

Researchers said that at the suggestion of several environmental scientists, they repeated their analyses for childhood leukemia using the United States Environmental Protective Agency's 1999 National Air Toxics Assessment modeled ambient 1,3-butadiene and benzene levels. In general, they saw a similar pattern.

Among adults, neither proximity to the Houston Ship Channel, nor levels of benzene or 1,3-butadiene was consistently associated with leukemia or lymphoma risk, the study said.

Mayor Bill White said the results will help spur city efforts to clean up the air.

A press release said researchers at the Health Department identified all cancer cases, including adult and childhood cases, diagnosed and reported to the Texas Cancer Registry from 1995-2003. They then used existing air monitoring data collected from 1992-2003 by the Texas Commission on Environmental Quality to estimate ambient census tract levels to benzene and 1,3-butadiene.

They also estimated the risk of developing leukemia and lymphoma associated with residential proximity to the Houston Ship Channel. They assigned cancer cases to a particular census tract based on their residence at diagnosis as reported to the Texas Cancer Registry. Researchers calculated cancer rates separately for adult and childhood cancers for each census tract. They also said they accounted for gender, age, socio-economic status, and ethnicity.

Distributed by Internet Broadcasting Systems, Inc. The Associated Press contributed to this report.