• Mohineesh Chandra All India Institute of Medical Sciences (AIIMS), New Delhi.
  • Jaya Raj All India Institute of Medical Sciences (AIIMS), New Delhi
  • Tirath Das Dogra SGT University, Budhera, Gurgao, India
  • Avinash Chandra Rajvanshi NICFS, Rohini, New Delhi-India
  • Anupuma Raina All India Institute of Medical Sciences (AIIMS), New Delhi


The best poisons usually have three things in common: Small effective dose, also called Median lethal dose 50 (LD50), ease of administration
and rapid and definitive action. Median LD50 is usually an initial screening step in the assessment and evaluation of the toxic characteristic of a
substance. It is the amount (dose)of a chemical, calculated as per the concentration of chemicals, which produce death in 50% of the population of
test animals to which it is administered by any of the methods such as oral, dermal inhalation or intravenous. Determination of this test examines
the relationship between dose and the most extreme response-death. The more potent or toxic the chemical, lower the LD50 and the smaller the
dose needed to cause death. LD50 figures are frequently used as a general indicator of a substance’s acute toxicity. The present study was designed
to evaluate the LD50 of triazophos (TZ), an organophosphorus pesticide in Wistar rats. A single oral dose of TZ was dissolved in Dimethyl sulfoxide
(DMSO) and administered orally at a concentration of 35, 55, 90 and 100 mg/kg respectively to experimental animals. LD50 of the TZ in DMSO
was found to be 72.44 mg/kg. Single dose of TZ at 35 mg/kg did not reveal any toxic signs or behavioral alterations, hence it is considered as No
Observed Adverse Effect Level (NOAEL). LD50 is a standard measurement of acute toxicity. Knowledge of LD50 is very important for toxicologists
to correlate or to identify a substance or any poison and to measure the short-term poisoning potential (acute toxicity) for drugs, food poisonings
and accidental domestic poisonings cases etc. The knowledge gained from dose-response studies in animals is used to set standards for human

Keywords: Preservative, Organophophorus, Triazophos, Butylatedhydroxyanisole, Lethal dose 50, No observed adverse effect level.

Author Biographies

Mohineesh Chandra, All India Institute of Medical Sciences (AIIMS), New Delhi.
Jaya Raj, All India Institute of Medical Sciences (AIIMS), New Delhi
Department of Forensic Medicine & Toxicology
Anupuma Raina, All India Institute of Medical Sciences (AIIMS), New Delhi


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How to Cite
Chandra, M., J. Raj, T. D. Dogra, A. C. Rajvanshi, and A. Raina. “DETERMINATION OF MEDIAN LETHAL DOSE OF TRIAZOPHOS (TZ) WITH DMSO IN WISTAR RAT”. Asian Journal of Pharmaceutical and Clinical Research, Vol. 7, no. 4, Sept. 2014, pp. 64-67,
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