Organophosphate Toxicity

Excerpt

Organophosphates encompass a diverse group of chemical compounds and are formed through esterification between phosphoric acid and alcohol. Currently, organophosphates have common applications in pesticides and herbicides, as well as nerve agents in chemical warfare. Therefore, most patients exposed to organophosphates typically encounter these compounds through the use of insecticides and herbicides. When introduced into the body, organophosphates inhibit the enzyme acetylcholinesterase (AChE), resulting in an overabundance of the neurotransmitter acetylcholine. This surplus of acetylcholine in the body manifests with cholinergic toxidrome, which includes effects on nicotinic and muscarinic receptors, as well as the central nervous system (CNS). The onset of symptoms, which varies based on the specific compound, frequently occurs within minutes, and resolution can take several weeks.

Although developed nations have experienced a decline in organophosphate poisoning cases due to stricter regulations on the use of these chemicals, developing countries have continued to grapple with clinical concerns related to this condition in recent years. Pesticides are frequently used as a means of self-harm due to their lethality and widespread availability in the developing world. Therefore, developing nations that heavily depend on agriculture and often have less stringent pesticide regulations result in the majority of cases of organophosphate toxicity. Research indicates that deliberate poisoning leads to a higher mortality rate than accidental exposure to these compounds. Respiratory failure resulting from bronchorrhea and bronchospasm is the leading cause of death in cases of organophosphate toxicity. Chronic toxicity and neurological complications, such as the intermediate syndrome, are also well documented. In industrial or developed nations, healthcare professionals must possess the capability to recognize this toxicity, given the potential for its utilization as a weapon in acts of warfare and terrorism. Antidotal therapy and comprehensive supportive care are necessary for the effective treatment of organophosphate toxicity to prevent morbidity and mortality.

History of Organophosphates Use

The first organophosphate insecticide was developed in the mid-1800s, but it only gained widespread usage after World War II. Initially, in the 1930s, these compounds were used as insecticides before finding application as neurotoxins by the German military. The organophosphate chemicals sarin and VX were utilized by the Japanese cult Aum Shinrikyo in 1994 and 1995, marking the initial reported instances of VX's use as a terrorist agent. In February 1997, the first reported murder involving VX occurred with the assassination of Kim Jong-nam at a Malaysian airport. In March 2018, the poisoning of Sergei and Yulia Skripal took place in England, leading to the hospitalization of a police officer who was also poisoned during this assassination attempt. The compound used in this event was the organophosphorus agent known as Novichok.