A new scientific analysis has found the incorrect application (and in some cases, completely dangerous) of insecticides onto local fruit orchards is associated with a rise in acute encephalitis syndrome (AES), which causes inflammation of the brain. The chemical spraying appears connected to the deaths of 13 children in a rural Bangladesh. The incident occurred during harvest time back in 2012; the results of the case have been published in July 2017.
Acute encephalitis syndrome leads to headache, fever, confusion, drowsiness, and fatigue. It can also be associated with seizures or convulsions, tremors, hallucinations, stroke, and memory problems; and sometimes death. There are various causes, from bacterial to viral, as well as chemical.
The researchers report that each of the death happened with 20 hours of the symptoms appearing. Laboratory testing reveals the children eat the fruit lychee, in the Dinajpur District in northern Bangladesh. The data correlates with similar deaths from eating the fruit, following pesticide spraying, in India.
According to the lead researcher in a communication sent to Digital Journal, Dr. M. Saiful Islam the deaths: “were most likely due to an exposure to multiple, highly toxic agrochemicals…These deaths occurred at a time when lychee was being harvested and consumed across Bangladesh. If the seeds were the cause, then we would expect to see cases scattered across the country, not just in a certain small area.”
The laboratory analysis was undertaken at the Institute of Epidemiology, Disease Control and Research in Bangladesh and at the U.S. Centers for Disease Control and Prevention. The digital testing, using chemical analysis, found the presence of endosulfan. Endosulfan is an off-patent organochlorine insecticide and acaricide that is being phased out globally. Endosulfan is acutely neurotoxic to both insects and mammals, including humans.
The tests required to detect the chemical are a combination of gas chromatography and mass spectrometry. Gas chromatography is used for separating and analyzing compounds that can be vaporized without decomposition. Testing includes assessing the purity of a particular substance, and the speed of testing has been advanced in recent years through the use of digital flowmeters, which can also provide portable testing solutions (such as the type manufactured by the companies Sigma or Merck). Mass spectrometry is an analytical technique that ionizes chemical species and sorts the ions based on their mass-to-charge ratio. The mass spectrum indicates the masses within a sample. The technology has also undergone an advance recently through the use of digital imaging, to enhance speed and accuracy.
The researchers will conduct follow-up studies undertaking liver and brain biopsies. In the meantime, they indicate that the case is strengthened for endosulfan to receive a worldwide ban. The findings have been published in the American Journal of Tropical Medicine and Hygiene. The research is titled “Outbreak of Sudden Death with Acute Encephalitis Syndrome Among Children Associated with Exposure to Lychee Orchards in Northern Bangladesh, 2012.”
