Environment | Daily Report

Drew from Zhrodague/FlickrIs toxic waste causing the birth defects and infant deaths in Kettleman City?

Something’s happening to the babies of Kettleman City.

Since the state started tracking birth defects in 1988, only one birth defect was detected in 20 years.

But that has changed.

According to a story in the current issue of Mother Jones, in the last two years and 10 months, 11 babies have been born with serious birth defects. Three died. A fourth was stillborn.

Birth defects include cleft lips and palates, as well as more serious maladies, including severe allergies, seizures and enlarged heads.

Despite Kettleman City's remote setting amid almond groves and tomato fields, its residents are exposed to a startling array of toxic chemicals [PDF]. Nearly 100 trucks spewing diesel fumes roll through town daily on Highway 41, and many more come by on Interstate 5. More than half of Kettleman City's labor force consists of farmworkers who are routinely exposed to toxic pesticides, and residents can smell the chemicals sprayed on the fields that border the town on three sides. Kettleman City's two municipal wells are contaminated with naturally occurring arsenic and benzene. And there are projects in the works to build a massive natural gas power plant nearby, as well as to deposit 500,000 tons per year of Los Angeles sewage sludge on farmland a few miles from the town.

But Kettleman City residents’ are most concerned about a hazardous-waste dump three miles from town. The dump, which is owned by Waste Management Inc., is the largest toxic-waste dump west of Alabama.

Last year, more than 350,000 tons of toxic waste was dumped at the site, including tens of thousands of pounds of asbestos, pesticides, caustics, petroleum products and more than 11,000 tons of material contaminated by polychlorinated biphenyls.

However, making a connection between the cluster of birth defects and any one cause – or even the large number of possible culprits existing in and around Kettleman City – is notoriously difficult.

For instance, if epidemiologists are looking for a cancer cluster, they have to show that: 1) there are a large number of cases of one kind of cancer, as opposed to several different kinds; 2) it is a rare type of cancer in the cluster, not a common kind; and 3) there is an increased number of cases of a certain type of cancer in an age group that usually does not get that type of cancer.

The same is true for other diseases and, in the case of Kettleman City, birth defects.

Dr. Rick Kreutzer, who heads California's Division of Environmental and Occupational Disease Control, says that even though the most common defect is a cleft palate, the differences in the other defects indicate that there is no single cause. "We don't really expect that we're going to find that one big thing," he says.

As a result, scientists are calling for new ways to analyze these clusters, including an approach called “cumulative impacts,” which examines the multitude of environmental concerns in a community and the variety of different ways the body handles these assaults.

"We think of biology more as a network now," says Amy D. Kyle, a UC Berkeley public health researcher and cumulative-impacts advocate. "There are lots of things going in your body at the same time, things get turned on and off, they can be interfered with to varying degrees by different chemical stressors. It's not like a road from A to B – it's more like traffic. If you have a crash, it doesn't stop all traffic. The whole system readjusts itself in ways that aren't linear. [In biology], the outcome depends on what else is going on – how old you are and what your other susceptibilities are, and the likelihood that multiple things can perturb these same pathways is greater than what we thought."

The state is investigating the Kettleman City situation.