A new study conducted by Johns Hopkins University found ethylene oxide (EtO) levels within Louisiana’s Cancer Ally average twice the threshold level set by the EPA for unacceptable cancer risks.

 

Airborne EtO is dangerous for long-term exposure at any level above 11 parts per trillion (ppt), according to the study. That threshold is very low, which says a great deal about the toxicity levels of this gas, notes science and technology news site Futurism.

"We expected to see [EtO] in this area," said study senior author Peter DeCarlo, an associate professor at the university's Department of Environmental Health and Engineering, according to Johns Hopkins’ news site, the Hub. "But we didn't expect the levels that we saw, and they certainly were much, much higher than EPA's estimated levels.

“We saw concentrations hitting 40 parts per billion, which is more a thousand times higher than the accepted risk for lifetime exposure.”

For many years, the 85-mile stretch of chemical plants located in southeastern Louisiana and stretching from Baton Rouge to New Orleans has been nicknamed “Cancer Alley.” Home to approximately 83 chemical plants and 45,000 residents, who are predominantly low-income black families, pollution from the plants has been blamed for high rates of cancer in the region.

Previous data has revealed that people living in the region “have a 95 percent greater chance of developing cancer than the average American,” says a Grist article published by DeSmog.

EtO is used in the production of commercial chemicals and for the sterilization and fumigation of medical equipment and in food safety, according to the study.

“EtO is extremely carcinogenic relative to other common hazardous VOCs (volatile organic compounds), and so even low levels of chronic EtO exposure pose substantial risks: the chronic EtO exposure concentration that corresponds to the upper limit of EPA’s acceptable cancer risk range … is 10.9 ppt,” the study states. “The cancer potency of EtO and how it should be regulated are currently hotly contested, both in courts and in the public square: industry groups dispute the accuracy of EtO’s toxicity, while environmental advocates think that EtO regulations need to be even tighter.”

The problem with measuring EtO levels is that the gas is difficult to detect or measure in the air through traditional monitoring methods that attempt to collect samples on-site and bring them back to a lab for analysis. Studies have shown that the compound concentrations change over time, so traditional measurement techniques are unlikely to reflect the correct exposure levels for those living near testing sites.

"There is just no available data, no actual measurements of [EtO] in air, to inform workers and people who live nearby what their actual risk is based on their exposure to this chemical," DeCarlo said in the Hub article.

In conducting the research for the study, the John Hopkins University team developed a way to directly measure EtO in the air at these facilities: a mobile lab.

“We went out to answer the question: How much ethylene oxide is in the air in this region and are the levels of concern for people's health?” said lead author Ellis Robinson, an assistant research engineer at Johns Hopkins. “Making it happen involved cutting-edge analytical equipment, analyzing data for about a month.”

When the teams’ measurements were compared with those able to be detected with the EPA's current screening tools, their own measurements were significantly higher.

“Our findings have really important implications for community residents, especially infants and children,” said Keeve Nachman, associate professor of environmental health and engineering and the co-director of the Risk Sciences and Public Policy Institute, according to the Hub. “[EtO] has been shown to directly damage DNA, meaning that exposures that occur in early life are more dangerous.”

“Our study demonstrates the need for more accurate measurements to help identify locations to install monitors for more long-term monitoring and so we can best protect the health of people who are living in those areas,” DeCarlo continued in the Hub article.

According to Reuters, the EPA said it would review the results of the study.

The Agency also “added that it had already taken steps to reduce pollution” in the area, which include “setting new standards for chemicals manufacturing and by conducting research into sources of EtO.”