Ministry of Agriculture

Toxicity & Hazard

Hazard Shapes & Symbols

Warning symbols

Visual warning symbols on pesticide labels indicate the kind of harm that can result from pesticide misuse or mishandling. They alert the user to the degree of the hazard (by the shape of the border) and to the type of hazard (by the centre "picture").

Poison symbol Poisonous
The "skull and cross bones" symbol warns that the chemical is poisonous if taken into the body. Keep the product out of reach of children. Use the appropriate safety measures when dealing with poisonous products.
flammable symbol Flammable
The "fire" symbol is a warning that the pesticide is flammable or easily ignited. Keep the pesticide away from heat, sparks, or open flames. Do not smoke while mixing or applying the product.
explosive symbol Explosive
The "exploding grenade" symbol indicates that the pesticide can explode, e.g., pesticide in pressurized cans. Explosive conditions may also be created by using Roundup or Rustler (glyphosate) in a galvanized steel spray tank.
corrosive symbol Corrosive
The "corroded hand" symbol indicates that the pesticide is corrosive to the skin and eyes. The chemical is either acid or alkali (caustic) and can burn the skin. Protect the skin and eyes when using these products.

Toxicity symbols

These symbols relate the oral LD50 value (mg/kg) of a pesticide to its toxicity symbol.

Danger poison symbolDanger Poison
LD50 less than 500 mg/kg indicates high toxicity.
warning poison symbolWarning Poison
LD50 500 to 1,000 mg/kg indicates moderate toxicity.
Caution Poison SymbolCaution Poison
LD50 1,000 to 2,000 mg/kg indicates low toxicity.
LD50 greater than 2,500 mg/kg indicates very low toxicity.

Interpretation of Symbol Combinations

Poisonous Hazard:
danger poison symbol
warning poison symbol
caution poison symbol
Acute oral LD50 < 500 mg/kg 500 - 1,000 mg/kg 1,000 - 2,000 mg/kg
Acute dermal LD50 < 500 mg/kg 500 - 1,000 mg/kg 1,000 - 2,000 mg/kg
Respirator yes advisable in confined spaces advisable in confined spaces
Eye Protection yes yes advisable
Eye Effects corrosive or irreversible severe but reversible irritation
Petroleum Distillates 10% or more 1% to 10% -

Flammability Hazard:
danger flammable symbol
warning flammable symbol
Caution Flammable Symbol
Liquid Products
- Flash Point
< -6°C
-6° to 10°C
(20° to 50°F)
10° to 27°C
(50°to 80°F)
Pressurized Products
- Flame Projection
45 cm
15-45 cm
(6 to 18")
< 15 cm

Explosive Hazard:
Caution Explosive Symbol
All Domestic Aerosols, Pressurized

Corrosive Hazard:
Danger corrosive symbol
Warner corrosive symbol
Caution corrosive symbol
acid or alkali materials 10% or more 5 to 10% 1 to 5%
organic acids 20% or more 5 to 20% 1 to 5%
available chlorine - 10% or more as liquid over 1% as solids
pH - 0.5 or 13.5 0.5 to 2.5 or 11.5 to 13.5
Available chlorine
> 4% and < 10% as liquid
Caution irritant symbol
Available chlorine
> 1% and < 4% as liquid
Caution Symbol

Additional Resources