Baton Rouge – The federal Agency for Toxic Substances and Disease Registry has updated the Department of Health on two new developments in the on going investigation of human dioxin exposure in Calcasieu Parish.

One update involves a follow-up to an investigation of blood-level dioxins of selected individuals, mostly from the Mossville community. The second is a comparison study of blood-level dioxins found in people in Calcasieu and Lafayette parishes. These investigations were prompted by findings in 1998 that showed some residents of Mossville had blood dioxin above the level used for comparison purposes (35 parts per trillion).

As a follow-up to the earlier exposure investigation, ATSDR returned to Mossville and Calcasieu and took additional blood samples from 22 individuals who participated in the first round of testing. Analysis of these new blood samples shows that 64 percent of the individuals had lower blood dioxin levels than previously noted. Thirty-two percent of those tested had levels greater than before, while 4 percent (one person) had the same level of dioxin in his/her blood. The average blood dioxin level for the 22 individuals is only slightly decreased from the earlier testing.

The second ATSDR update involved the comparison study of Calcasieu and Lafayette parish residents. In this study, blood was drawn from 414 volunteers, 294 people from Calcasieu and 120 individuals from Lafayette. The ages of the participants ranged from 15 to 91 years of age. The purpose of the study was to compare blood dioxin levels from citizens who lived in a highly industrialized community to those who did not. The belief was that exposure to industrial emissions would cause higher levels of dioxin in the blood.

Preliminary findings from this comparison study show that people who live in Calcasieu and Lafayette have similar dioxin levels. In addition, the study found that in Calcasieu, there was no difference in dioxin levels between people who live closer to industry than those who lived farther away. Dioxin levels by age group are similar in both parishes, but older people are more likely to have higher levels than younger residents. This is consistent with national findings that show older people higher dioxin levels. Most people in both parishes have levels below ATSDR’s best estimate of background/comparison levels.

Dioxin and dioxin-like compounds are formed by burning chlorine-based chemicals with hydrocarbons. The major environmental sources of dioxin-like compounds are the result of the combustion of chlorinated compounds and other substances (such as household garbage). Elevated levels of dioxin-like compounds are known to cause a skin disorder called chloracne and increases in liver enzymes. Research shows that 95 percent of human exposure to these compounds comes from food sources. Minute quantities can be found throughout the environment and enter the food chain after being absorbed by plants and animals.

LDH Secretary David Hood said he was pleased that federal officials have alerted the state health department of these findings.

"In 1999, we began working with state and federal agencies to better understand human exposure to dioxin," Hood said. "Our initial public health response focused on the small community of Mossville, where we conducted several subsequent studies to try and answer questions residents had at the time. Without a doubt, this new information is compelling. I suspect these studies will prompt more questions from citizen in both communities, and we will continue to work with our federal partners to address concerns."

In early 2000, DHH’s Office of Public Health undertook the following public health actions: 1) Identify and reduce current dioxin exposures; 2) conduct a residential needs assessment in Mossville to gather information about demographics, occupation, lifestyle and residential history; 3) identify clinical resources in the area; 4) perform a cancer statistics review of Calcasieu Parish and Mossville residents to identify any elevated cancer rates; and 5) provide environmental health education to residents of Mossville and their health care providers.

To date, LDH has completed all but the first action. Hood added that LDH and its Office of Public Health will continue to work with ATSDR to analyze this new information and make further public health recommendations.

"This latest information from the ATSDR is valuable when it comes to the next steps necessary to identify or reduce dioxin exposures," Hood said. "I am also encouraged that ATSDR believes that blood dioxin at these levels should not cause health effects. But, they have cautioned us that further analysis is needed before anyone can draw definitive conclusions from the findings."

Hood added that ATSDR stated it will return to Louisiana in the summer to present the final result of these investigations.

"At that time, I hope that we will receive some clear understanding of what these findings mean, and if these levels of dioxin are much different than levels found in other communities," he said.