Tuesday, November 08, 2005

DDT Byproduct Brings Upheaval to Small Michigan Town

St. Louis, Michigan, a small city 50 miles north of Lansing, has been put on the map because of its problems with toxic waste. The government found old pesticides laced deep into the bottom of the river that cuts through the middle of town and a syrupy ooze of industrial poisons pouring out of the dump where the city's old chemical plant is buried. Every time it solves one problem, another turns up. And now something has bled into the city's drinking water. Federal officials insist the byproduct of DDT production they detected in three of the city's wells in tests over the past year is not dangerous, though many people don't believe them.

"We never drank the water. Everyone always knew it was contaminated," said a resident of St. Louis, "Now they just have proof."

The city is asking the U.S. Environmental Protection Agency to finally dig up all of the old pesticides and flame retardants buried beside the plant. As far as the EPA knows, St. Louis is the only city in the country where para-chlorobenzene sulfonic acid,p-CBSA, a byproduct of the pesticide DDT, has been found in drinking water. The agency told the city in September it had detected low levels of the chemical in wells that supply half of the city's water. No one knows how long it's been there. But the city isn't taking chances. It stopped pumping water from the wells where the EPA found contamination; city officials are thinking about drilling new ones. The schools turned off their drinking fountains and sent workers out to buy truckloads of bottled water. Not that many people drank the city water before mainly because of the chemical plant buried a quarter-mile from the closest city wells. "Who knows if it's safe or not," said another resident, who has lived for a decade in St. Louis without drinking the water. The highest concentrations of p-CBSA found in city wells are 140 times lower than the level the EPA has said could put people's health at risk. But water samples taken over the summer from a monitoring well across the street from the two city wells closest to the plant found concentrations of the chemical that are at least 11 times higher than the agency's safety threshold. The few studies that have been done found that p-CBSA is not harmful in low doses, but did not measure the effects of long-term exposure. Senators Carl Levin and Debbie Stabenow demanded last month that the EPA conduct a more thorough study. The discovery could point to bigger problems ahead: If fast-moving p-CBSA can find an underground channel from the chemical dump to the city's wells, other, more harmful chemicals might follow. That's why the EPA tested for it in the first place. When the Velsicol Chemical plant closed in early 1978, the entire operation was buried where the plant had once been. The company was then required to cover the dump with a layer of clay and surround it with an underground wall to keep the chemicals there from leaking out. This attempt to prevent the spread of chemicals failed miserably. In 1997, the EPA found dangerous levels of DDT in the muck at the bottom of the Pine River that flows through the town. The reparation of this problem dug up even more problems. The worst was a thick ooze of highly concentrated DDT and other toxins seeping out from beneath the plant. That prompted a state and federal investigation of what to do about the leaks from the site. And that's when they found something in the water

Friday, November 04, 2005

125 Years and Still No Relief

It was on the 6th of November in 1880 that Charles Alphonse Laveran discovered the parasite that causes Malaria. After 125 years, it is still one of the world’s most deadly diseases, despite world-wide research to find a cure. To commemorate 125 years since its discovery, an International Conference on Malaria has been organized in New Delhi from November 4th until November 6th, by the Malaria Research Center in collaboration with the National Vector Borne Diseases control program. The Minister for Health and Family Welfare, Dr. Anbumani Ramadoss will open the conference by addressing the challenges in controlling the disease. While eradication of Malaria still remains a big question, containing it, limiting it, and controlling it will be the focus of this conference. Also the immunity the parasite is developing to drugs, DDT, etc. will also be addressed. Various national programs on Malaria aim at conducting basic, applied, and operational research to reduce the number of deaths due to Malaria to the level that it is no more considered a serious public health problem and eventually eradicate it entirely.

For more see: http://pib.nic.in/release/release.asp?relid=13050

Friday, October 28, 2005

DDT Alternatives in Mexico

Public health experts in Mexico, along with the nation's Malaria Control Program (MCP), are searching for new ways to fight malaria without using DDT. A multi-disciplinary team funded by the International Development Research Center (IDRC) is looking at ways to manage the local environment to reduce the incidence and spread of malaria. The team is focusing on the State of Oaxaca which is the main site of malaria outbreaks in Mexico. "We're looking at malaria from many different angles including the molecular biology of the vector and the parasite, community perceptions of malaria, statistical analyses, and a geographic information system (GIS)-based surveillance system,” says Juan Hernandez, Director of Informatics at the National Institute of Public Health. The MCP's long-term goal is to prevent future outbreaks of malaria, without harming the local environment. DDT has been the main tool used in fighting malaria but since it is dangerous to the environment, the MCP has decided against using it. The research team used geographic information system (GIS) tools to analyze different areas in Oaxaca in terms of malaria incidence and frequency, elevation, climate, hydrology, distance to rivers and roads, and short-range human movements. The team found that cases of malaria occurred more frequently in areas with closely clustered villages and in places where health facilities are scarce. The researchers are now focusing on humans as the main vector. A vector is an organism that carries a disease-causing microorganism from one host to another. The researchers have found that mosquitoes merely introduce the disease into the population but without the availability of medical treatment the people with the disease cause it to spread. The MCP is also working on an algae removal strategy, the purpose of which is to reduce the number of disease carrying mosquitoes in the area; they are giving people who have had malaria before malaria medicine to prevent them from relapsing; and they are working on rapid diagnosis of people showing symptoms of malaria to get them treatment more quickly. The rapid diagnosis approach is currently being evaluated in 20 different areas. The new malaria control strategies are working well, between 1998 and 2001 the number of malaria cases had fallen sharply.

Just for Fun: A DDT Limerick

A mosquito was heard to complain
A mosquito was heard to complain
That a chemist had poisoned his brain
The cause of his sorrow
Was paradichloro
Diphenyltrichloroethane.

by
Dr. D. D. Perrin

Friday, October 14, 2005

DDT Linked to Early Miscarriages

A recent study conducted at the Harvard School of Public Health has shown that women with high levels of DDT in their bloodstream are far more likely to miscarry in the early weeks of pregnancy than those with lower levels. The participants in the study were newly married, healthy, nonsmoking textile workers in China, who were trying to get pregnant. The women ranged from ages 20 to 34. Even though DDT was banned decades ago, the chemical residue can be found in most people, no matter how far they lived from where DDT was used or produced. The Chinese women who participated in this study were found to have an average level of DDT residues about ten times higher than those ordinarily found in the United States. The levels were similar to those found in countries where DDT was more recently used. The study found that the women who had the most DDT in their system were more likely to miscarry in the early weeks of pregnancy, before they even knew they were pregnant. The researchers found that for every additional 10 nanograms of DDT per gram of serum, a woman’s chance of early miscarriage rose by about 17 percent. The chance that DDT is linked to infertility was not investigated by this study.

For more information: http://www.sciencedaily.com/releases/2005/09/050912124225.htm
For the full version of the study: http://aje.oxfordjournals.org/cgi/reprint/kwi275?ijkey=h9AKIxsz45iaLkB&keytype=ref

Friday, October 07, 2005

The Beginnings of DDT

In 1948, Dr. Paul Muller received the Nobel Prize for Medicine for his discovery of DDT’s toxic effect on insects. Tiny amounts of this chemical could kill a large amount of insects and studies showed that it was not very toxic for plants or animals. It was first put to use in 1939 to wipe out the Colorado potato beetle that was destroying Switzerland’s potato crop. It was then used successfully to protect soldiers from mosquitoes, body lice, and other disease spreading insects. DDT had proven to be exactly what Muller had been looking for.

Dr. Muller had been working in the dye division of the J. R. Geigy Corporation researching natural products to be used as pigments and tanning agents for leather. He was researching this until 1935 when he was assigned to develop an insecticide. He was looking for a compound that would have a rapid potent toxicity for the most species of insect; that would be stable enough to last long periods of time; and that would cause little or no damage to plants and animals. DDT satisfied all of Muller’s requirements and it was thought to be an ideal insecticide, until people realized it was being overused and because of the chemical’s persistence, there was too much of it in the environment. This created a hazard to animal life and spurred people like Rachel Carson to fight and have DDT banned.