German doctors said on Monday that tests on Russian opposition figure Alexei Navalny indicate poisoning with some kind of cholinesterase inhibitor, although the specific substance is not yet known.
Here are five facts about cholinesterase inhibitors:
- Cholinesterase inhibitors are a group of chemical compounds used in everything from chemical weapons, to pesticides designed to kill bugs, and human medicines designed to alleviate symptoms of Alzheimer's and other types of dementia.
- Cholinesterase is an enzyme that is critical for the normal function of the nervous system in humans, other vertebrates, and in insects.
- Chemicals that block, or inhibit, cholinesterase can cause overactivity of a wide variety of bodily functions, leading to multi-system acute effects that can be lethal.
- Certain pesticides, such as organophosphates and carbamates, work by inhibiting cholinesterase. These chemicals can also be poisonous to humans in some situations.
- Human exposure to cholinesterase inhibiting chemical pesticides can result from inhalation, ingestion, or eye or skin contact during their manufacture, mixing, or application.
(Reporting writing by Kate Kelland, editing by Giles Elgood)
