The information in this profile may be out-of-date. It was last revised in 1996. EXTOXNET no longer updates this information, but it may be useful as a reference or resource.

Please visit the National Pesticide Information Center (NPIC) to find updated pesticide fact sheets. If you don't find a fact sheet related to your question, feel free to call 1-800-858-7378. NPIC is open five days a week from 8:00am to 12:00pm Pacific Time.


Extension Toxicology Network

Pesticide Information Profiles

A Pesticide Information Project of Cooperative Extension Offices of Cornell University, Oregon State University, the University of Idaho, and the University of California at Davis and the Institute for Environmental Toxicology, Michigan State University. Major support and funding was provided by the USDA/Extension Service/National Agricultural Pesticide Impact Assessment Program.

EXTOXNET primary files maintained and archived at Oregon State University

Revised June 1996


Trade and Other Names: Trade names for products containing methidathion include Somonic, Somonil, Supracide, Suprathion and Ultracide. The compound may be found in formulations with many other pesticides.

Regulatory Status: Methidathion is an highly toxic compound in EPA toxicity class I. Labels for products containing it must bear the Signal Word DANGER. Methidathion is a Restricted Use Pesticide (RUP), except for use in nurseries, and on safflower and sunflowers.

Chemical Class: organophosphate

Introduction: Methidathion is a non-systemic organophosphorous insecticide and acaricide with stomach and contact action. The compound is used to control a variety of insects and mites in many crops such as fruits, vegetables, tobacco, alfalfa, and sunflowers, and also in greenhouses and on rose cultures. It is especially useful against scale insects. It works by inhibiting certain enzyme actions in the target pests. It is available in emulsifiable concentrate, wettable powder, and ultra-low volume (ULV) liquid.

Formulation: It is available in emulsifiable concentrate, wettable powder, and ultra-low volume (ULV) liquid formulations.

Toxicological Effects:

Ecological Effects:

Environmental Fate:

Physical Properties:

Exposure Guidelines:

Basic Manufacturer:

Ciba-Geigy Corporation
P.O. Box 18300
Greensboro, NC 27419-8300


References for the information in this PIP can be found in Reference List Number 5

DISCLAIMER: The information in this profile does not in any way replace or supersede the information on the pesticide product labeling or other regulatory requirements. Please refer to the pesticide product labeling.