Dursban (chlorpyrifos), a pesticide made by the Dow Chemical Company, is the subject of numerous lawsuits. The pesticide is known to be particularly dangerous to children, and has been tied to birth defects and neurological problems. Dursban is so dangerous that many of its uses were banned by the U.S. Environmental Protection Agency (EPA) in 2000. However, its use has not been entirely eliminated.

Plaintiffs in Dursban lawsuits allege that exposure to the pesticide poisoned their children, thus causing nerve damage, including paralysis, as well as birth defects. Other maladies alleged in Dursban lawsuits include cancer, infertility, hepatitis, pancreatitis, paralysis and mental retardation.

Dursban is an organophosphate pesticide that kills by attacking the nervous system. Such chemicals were first developed in the 1930s by the Nazi regime as chemical weapons. Prior to the EPA ban, Dursban was the most popular household pesticide in the U.S., and could be found in over 800 products. In one sampling of American children, more than 90 percent of the study group had chlorpyrifos present in their urine.

Exposure to Dursban from inhalation, skin contact or ingestion impacts the central nervous system, the cardiovascular system and the respiratory system. It usually produces complaints such as initial flu-like illness followed by chronic complaints of fatigue, headaches, dizziness, loss of memory, upper and lower respiratory symptoms, joint and muscle pain and gastrointestinal disturbances.

Severe poisoning will affect the central nervous system, producing lack of coordination, slurred speech, loss of reflexes, weakness, fatigue, muscle contractions, twitching, tremors of the tongue or eyelids, and eventually paralysis of the body extremities and respiratory muscles. Death may be caused by respiratory failure or cardiac arrest.

Studies of pregnant migrant workers and their children have shown that exposure to Dursban caused, among other things, low birth weights, severe and unusual birth defects (primarily to the size and circumference of infants' heads), motor and cognitive delays, attention deficit disorder, and an increased risk of neural tube defects.

In June 2000, after a lengthy review, the EPA reached an agreement with Dow Chemical to banned most home and garden uses of Dursban, citing health risks to children. The EPA directive also restricted its application in agriculture. The agency also required that Dursban use be phased out in areas where children would be most likely to be exposed - schools, daycare centers, parks and recreation areas, stores and malls.

Unfortunately, under the phase out, all stocks of the pesticide were permitted to remain on store shelves until they were used up. As a result, people continued buying Dursban products, often ignorant of their health risks. It's impossible to know how many children were poisoned by Dursban during this time.

The phase-out did not eliminate all agricultural uses of Dursban. It is still widely used in agriculture especially on cotton, corn and almonds crops, as well as fruit trees including oranges and apples

Dow Chemical has faced allegations that it withheld information about Dursban's risks, and marketed it as a safe pesticide, despite knowing the opposite was true. In 1995, for instance, Dow was fined $732,000 for not sending the EPA its reports on 249 Dursban poisoning incidents.

In 2003, Dow agreed to pay $2 million - the largest penalty ever in a pesticide case - to the state of New York. The state had filed suit against Dow for repeatedly violating a 1994 agreement that prohibited advertising that touted the safety of its pesticide products. However, an investigation found that almost immediately after the company entered into the agreement, it once again began to make misleading safety claims in its print, video and internet advertising.