A new study conducted by researchers from Sri Lanka, Australia and the UK found that people dying from pesticide poisoning are more likely to develop nerve and nerve/muscle disorder days before they die.
The common class of chemicals, organophosphates is used widely in many insecticides, pesticides and herbicides. Hundreds of thousands of people die every year due to exposure to pesticide, mostly suicide cases, as it is easily available in rural areas.
Lead author of the study, Pradeepa Jayawardane and team found that there are changes in nerves transmission are presented before the development of intermediate syndrome (IMS), which results in muscle weakness in the limbs, neck, and throat and failure of respiratory system.
The findings of the study appear in PLoS Medicine. The researcher says that the result of the study will help in improving the management of patients suffering from pesticide poisoning.
Pradeepa Jayawardane, a clinical pharmacology lecturer at the University of Sri Jayawardenepura in Sri Lanka, along with team of researchers from Sri Lanka, Australia and the UK conducted the study on 78 people admitted in Sri Lankan hospitals with organophosphate poisoning. The scientists found that 10 patients (12.8 percent of patients) were suffering from severe weakness in their neck and limb muscles and 5 of these eventually developed respiratory failures.
Organophosphates poisoning causes respiratory failure, which is the main reason behind the death of many people.
The scientist used repetitive nerve stimulation (RNS) technique, where a series of small electrical shocks was applied to the certain muscles in the arm of the patients and the responses in the muscles that these nerves control were recorded. The researchers found specific changes in nerve transmissions in the ten subjects and 5 of them did eventually developed respiratory failure.
The researchers concluded that, "IMS is a spectrum disorder. At one end of the spectrum the patients demonstrate only the electrophysiological abnormalities without clinically detectable muscle weakness, and at the other end, patients progress to severe muscular weakness with deterioration of electrophysiological measurements and the risk of respiratory failure."
Since the clinical signs of intermediate syndrome emerged after the changes in nerve transmission, the experts advised using the changes as an indicator of future poor outcome.
Aaron said, "If these distinctive electrophysiological changes are subsequently validated in further studies, they should lead to improved diagnostic and prognostic tools for clinical use in organophosphate-poisoned patients".
Due to easily availability and low price, pesticide related deaths, especially among farmers are common in some of the developing countries in Asia. The aid agencies have been trying to ban the pesticide or at least limiting their use.
Organophosphate poisoning can cause 3 syndromes. First one is the cholinergic syndrome which can be fatal and happens immediately after organophosphates are inhaled, swallowed or absorbed through the skin. Second is the intermediate syndrome (IMS), which causes weak muscles and develops between one to four days in some patients. The third one is long-term nerve damage which sometimes develops 2 to 3 weeks after poisoning.
Approximately, every year there are 25 million cases of pesticide poisoning. While most pesticides are applied in developed countries, 80 percent of all poisonings occur in developing countries where regulatory, health, and education systems are weakest.
According to some reports, exposure to excessive levels of organophosphate pesticides may cause runny nose, temporary cough and burning eyes near the time of exposure. And long term exposure may result in lingering effects months or years later.
The continuous symptoms are fatigue, joint and muscle pain, memory problems, headache, respiratory problems, dizziness, gastrointestinal disturbance, atrophy, and antibioticdefine sensitivity 1 to several years after exposure.