HERBICIDE TOXICITY AND HAZARDS 



E.H. Wheeler 

 Professor of Entomology 

 Leader, Pesticide Chemicals Program 



(Adapted from article by Dr. J.E. Dewey, 

 Volume 4 (No. 10), December, 1968). 



in Cornell Newsletter, 



Many users of herbicides have not realized that herbicides are 

 pesticides and that they can be highly toxic. Many users treat her- 

 bicides as though they were no more toxic than drinking water. Be- 

 cause of this total disregard for possible toxicity, many needless 

 accidents have occurred. 



Even materials like 2,4-D and 2,4,5-T are not free from hazard, 

 as well illustrated by deaths resulting from the ingestion of com- 

 mercial formulations and sickness following inhalation and excessive 

 contact as reported by the National Clearinghouse for Poison Con- 

 trol Centers 



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rther illustration of the hazards of herbicides, con- 

 at and Diquat, These materials have been widely used 

 with reckless abandon. The oral LDrn to rats is 150 

 g respectively. Other things being equal, these levels 

 sidered only moderately toxic. Unfortunately, in the 

 e materials, other things do not appear to be equal, 

 es in which these materials have been taken orally by 

 tremely small quantities taken into the lungs have 



unknown lung deterioration. Once this action is ini- 

 ppears that death is almost certai n and that there is 

 i dote . Death may result in a few days , a week, or 2 

 dependi ng on the dose. 



From a practical point of view this means that care should be 

 taken not to breathe the mist of these sprays. Breathing the mist 

 or drift is believed to be more serious than low level ingestion. 

 Masks should be worn to remove droplets and particulate matter 

 from the air inhaled. Drift may he more a hazard to others than to 



