DDT Conference Receives National Endorsement
The consensus statement drafted by a panel of experts who convened at Alma College in March 2008 to review the link between DDT and human health has received significant national exposure.
After a review of nearly 500 epidemiological studies, the conference researchers developed a consensus statement calling for increased efforts to reduce exposure to DDT and to develop alternatives to using DDT for malaria control.
The consensus statement has been published in Environmental Health Perspectives, the premier academic journal in environmental health. Articles about the statement have appeared in the online versions of Environmental Health News and Scientific American.
DDT conference participants in March 2008.
“This is great news,” says Ed Lorenz, director of Alma College’s public affairs program. “Alma College and the greater Alma community have participated in a remarkable public health event, whose merit has now been endorsed by a peer reviewed academic process.”
The consensus statement emerged from the Eugene Kenaga International DDT Conference, jointly organized by the Pine River Superfund Citizen Task Force and Alma College’s Public Affairs Institute and Center for Responsible Leadership. More than 200 participants attended the conference, which was held near St. Louis, Mich. where a chemical plant leaked massive levels of DDT into the Pine River. In 1983, the area was named a Superfund site by the U.S. Environmental Protection Agency.
Conference Participants Were Engaged
The scholars acknowledge that the use of DDT has prevented millions of infections and deaths of insect-borne diseases, especially malaria. Yet, substantial exposure to DDT poses serious health risks for human populations and the environment, says Lorenz.
“Millions of people die each year from malaria, most of whom are under the age of five,” says Lorenz. “However, the conference scholars have documented in numerous human health studies what can be called a ‘deepening understanding of the effects of DDT use on humans.’ The collective wisdom of the experts at the Kenaga Conference was that world policymakers need to use extreme caution when considering easing restrictions on DDT use.”
Conference participants were engaged from the moment they arrived on the Alma College campus, according to Alma College students who served on the conference planning committee.
“It went leaps and bounds beyond what any of us expected, not only in the response from the local community but also in the response from the environmental and health experts from the U.S. and abroad,” says Rachel Naiukow, a 2008 graduate. “They all concluded from the beginning that they wanted something big to emerge. The publishing of the consensus statement is phenomenal, but I also hope that the statement will result in policy that will benefit the global community.”
“It was great to have a big idea and goals and see them transform into reality,” says 2009 graduate Drew Emge, who has been accepted into the master’s degree program at the London School of Hygiene and Tropical Medicine. “The conference exceeded all my expectations and was a tremendous learning experience.”
Indoor Spraying Puts People At Risk
In regions where malaria is endemic, the synthetic pesticide is now sprayed inside buildings and homes to repel and kill the mosquitoes that spread the disease, according to lead author Brenda Eskenazi, UC Berkeley professor of epidemiology and maternal and child health at the School of Public Health. This is being done despite a “paucity of data” on the human health impacts of DDT exposure at such high levels, according to the experts from fields ranging from environmental health to cancer biology.
"We have to put our concerns in the context of people dying of malaria," says Eskenazi. "We know DDT can save lives by repelling and killing disease-spreading mosquitoes. But evidence suggests that people living in areas where DDT is used are exposed to very high levels of the pesticide. The only published studies on health effects conducted in these populations have shown profound effects on male fertility.
“Clearly, more research is needed on the health of populations where indoor residual spraying is occurring, but in the meantime, DDT should really be the last resort against malaria rather than the first line of defense,” she says.
The researchers noted that the majority of studies on DDT have focused on the impact on wildlife and the environment. Of the studies published on human health, almost all have dealt with populations exposed to low, background levels of DDT. Nevertheless, some of those studies have suggested links between DDT and cancer risk, diabetes, developmental problems in fetuses and in children, and decreased fertility.
"Any studies conducted up to now on the human health effects from DDT exposure may not be relevant to the populations currently exposed to the pesticide through indoor residual spraying," said Eskenazi, who has published research on the negative impact of DDT exposure to a child's neurodevelopment.
More Training, Monitoring Needed
Moreover, most of the studies on DDT and human health were done in developed countries where the pesticide was banned in the 1970s, the researchers said.
"DDT is now used in countries where many of the people are malnourished, extremely poor and possibly suffering from immune-compromising diseases such as AIDS, which may increase their susceptibility to chemical exposures" says co-author Jonathan Chevrier, UC Berkeley post-doctoral researcher in epidemiology and in environmental health sciences.
DDT has been banned in the United States since 1972. To date, more than 160 countries have signed the Stockholm Convention on Persistent Organic Pollutants, an international treaty banning DDT and 11 other persistent organic pollutants, except when needed for malaria control.
In cases where DDT must be used, the Stockholm Convention requires an implementation and management plan to minimize the pesticide's exposure to humans and its release into the environment. However, the authors noted, little oversight exists to ensure that those plans are being carried out properly.
"There are anecdotal reports of people failing to remove their clothes and cooking utensils from their homes before DDT spraying," said Chevrier. "More training and monitoring is needed to prevent such instances."
Alma College and the Pine River Superfund Citizen Task Force were the 2008 recipients of the Jimmy and Rosalyn Carter Partnership Award for Campus-Community Collaboration, the premier community service award by Michigan Campus Compact for higher education and community collaboration.
Posted: Tue, May 5th, 2009 at 3:24PM