Research Methods in Toxicology and Insecticide Resistance ...

Toxicology (derived from two Greek words, “toxicos” = poisonous and “logos”
= study) is a very broad fi eld of study involving multidisciplinary sciences
related to adverse chemical effects on living organisms—including humans.
It has many defi nitions. Generally, toxicology can be defi ned as “the study of
adverse, deleterious, and/or poisonous effects of chemicals on living organisms” or
“the study of symptoms, mechanisms/mode of action, treatments, and detection of
poisoning; and cause of resulting death.”
A brief history
According to popular Chinese mythology, Shennong, “the divine farmer” (about 2696
BC), is credited for bringing agriculture to ancient China (Wu 1982). He is also known
as the father of Chinese medicine for writing a treatise “On Herbal Medical Experiment
Poisons.” He was noted for tasting 365 herb species, from which he eventually
died, probably as a result of a fatal dose.
In 399 BC, the Athenian philosopher Socrates was tried and found guilty for two
charges, related to Greek gods and deities, brought against him. He was sentenced
to death and executed by drinking a liquid containing hemlock, a poisonous alkaloid
from the plant Cornium maculatum (Apiaceae), for teaching radical ideas to Athenian
youths (Stone 1988). Then, in AD 50–400, the Romans used poisons to carry out many
executions and assassinations.
Abu Ali Sina, also known as Avicenna (AD 980-1036), was a Persian scholar and
philosopher. He wrote more than 400 treatises related to various aspects of human
logic, diseases, health, pharmacology, and physiology (Nasr 2007). Two of his outstanding
works were “The Canon of Medicine” and “The Book of Healing.” He was
responsible for limiting the spread of infectious diseases by introducing quarantine.
Through his knowledge of Islamic alchemy, chemistry, and pharmacology, he was an
authority on poisons and antidotes.
Moses Maimonides (AD 1200) of Jewish descent was born in Spain. He worked
as a rabbi, philosopher, and physician in Spain, Morocco, and Egypt. He wrote ten
medical works in Arabic, one of which was a fi rst-aid book for poisonings titled
“Treatise on Poisons and Their Antidotes.” This is an early textbook dealing with
medical toxicology (Rosner 2002).
Phillip von Hohenheim, better known as “Paracelsus” (1493-1541), was born a
Swiss and worked in Austria as a Renaissance physician, alchemist, astrologer, and
botanist. He is noted for his statement in German, “Alle Ding’ sind Gift, und nichts
ohn’ Gift; allein die Dosis macht, daß ein Ding kein Gift ist” (translated as “All
things are poison and nothing is without poison, only the dose permits something
not to be poisonous”). He was the fi rst to explain the dose-response relationship of
toxic substances—toxicity of a poison expressed as “lethal dose” (LD). For that, he
is sometimes known as “the father of toxicology” (Madea et al 2007).
Mathieu Orfi la (1787-1853) was born in Spain and worked as a French chemist
and toxicologist. He played a major role in forensic toxicology, and was credited with
being the founder of toxicology as a distinct scientifi c discipline, which he established
in 1815 (Bertomeu-Sánchez and Nieto-Galan 2006).
Research methods in toxicology and insecticide resistance monitoring of rice planthoppers 3