dc.description.abstract | Human poisoning with chemicals, including drugs, is emotive because of the real possibility that it often
culminates in death. In acute poisoning, clinical symptoms such as vomiting, delirium, diarrhoea,
convulsions, et cetera, are very dramatic, yet the onlookers with no medical background can only watch
helplessly as the poisoned patient writhes in pain, crying for assistance, fearful of impending end result.
In the case of self-poisoning, the victim aims to send a protest message usually to immediate relatives and
friends, leaving them nursing a guilty conscience. Conversely, chronic poisoning is insidious, occurs over
a long period and is rarely accompanied by dramatic episodes characteristic of acute poisoning. Often, it
is mistaken for a disease. Several examples of chronic poisoning abound. Lead poisoning, common
among workers in the paint industry, occurs over a long period and leads to impairment of neurocognitive
functions. In the 1950s, a neurologic disease occurred in the Japanese village of Minamata. It is only later
that the causative agent was identified to be methylmercury formed in sea water by metabolic action of
aquatic organisms on elemental mercury discharged from a nearby factory. Bioaccumulation of
methylmercury then occurred in fish which were eventually eaten by humans. Thallium poisoning is
characterized by alopecia often seen one to two weeks later when the patient is about to be discharged
from hospital. Thus, in chronic poisoning, it is difficult to establish definitive cause-effect relationship
particularly for purpose of litigation. | |