Toxicity is the intrinsic ability of a substance to cause toxic or death to other organisms. Pesticides can cause direct or indirect toxic effects on humans, animals, poultry and other animals, causing their physiological functions to be destroyed. This property is called pesticide toxicity. The magnitude of toxicity is indicated by the nature and extent of the damage produced.
Pesticide toxicity grading product determines the use of pesticide products and the level of attention pesticide production, and sales of its users, thus affecting their safety. If the toxicity grading standards of pesticides are set too strict, it will limit the scope of use of many pesticide products, affecting their production, use and sales, and even affect the development of the pesticide industry. If the pesticide toxicity grading standard is too loose, it will cause pesticide production, sales, and users' toxic awareness of pesticides, and even use some highly toxic and highly toxic pesticide products unreasonably for vegetables, fruits, tea and Chinese herbal medicines. Wait, cause poisoning of humans and animals.
1. World Health Organization's pesticide hazard classification
The classification criteria for pesticide hazards recommended by the World Health Organization was adopted at the World Health Legislative Assembly in 1975. It is mainly based on the acute oral and transdermal LD 50 values ​​of the pesticides (rat, the same below). The hazards of pesticide products are graded (?).
Table 1 World Health Organization's pesticide hazard grading standards
Toxicity classification | Level symbol | Half the lethal dose ( mg/kg) | Percutaneous median lethal dose ( mg/kg) | ||
solid | liquid | solid | liquid | ||
I a level | Very toxic | ≤ 5 | ≤ 20 | ≤ 10 | ≤ 40 |
I b level | High toxicity | > 5~50 | > 20～200 | > 10～100 | > 40～400 |
Level II | Moderate poison | > 50～500 | > 200～2000 | > 100-1000 | > 400～4000 |
Level III | Low toxicity | > 500 | > 2000 | > 1000 | > 4000 |
2. US pesticide toxicity classification
The toxicity classification of pesticides in countries all over the world is usually based on the classification criteria of pesticide hazards recommended by the World Health Organization, and is formulated according to the actual situation in the country. Therefore, the toxicity classification and labeling management of pesticide products are not completely the same in each country. For example, the toxicity classification of pesticides in the United States is based on the classification criteria for pesticide hazards recommended by the World Health Organization ( WHO). The results of eye-stimulation and skin irritation tests based on pesticide products are added, and the highly toxic and high-toxic levels are combined into one level. And slightly proposed micro-toxic pesticides (Table 2).
Table 2 US pesticide toxicity grading standards
Toxicity classification | Level symbol | Half of the mouth Lethal dose ( mg/kg) | Percutaneous half Lethal dose ( mg/kg) | Half inhaled Lethal concentration ( mg/L) | Eye irritation | Skin irritation |
Level I | Highly toxic, highly toxic | ≤ 50 | ≤ 200 | ≤ 0.2 | Corrosive, irreversible corneal opacity | Corrosive |
Level II | Moderate poison | 50 to 500 | 200～2000 | 0.2 to 2.0 | 7d recoverable in corneal opacity, continuous stimulation 7d | 72h severe stimulation |
Level III | Low toxicity | 500-5000 | 2000-20000 | > 2.0-20 | No corneal opacity, recoverable stimulus within 7 days | 72h moderate stimulation |
Level IV | Microtoxic | ≥ 5000 | ≥ 20000 | ≥ 20 | No stimulation | 72h mild or moderate stimulation |
3 EU pesticide toxicity classification
European pesticide toxicity grading standards are also developed in accordance with WHO's recommended grading standards, and consider the form of product presence, but only in three levels (Table 3).
Table 3 EU pesticide toxicity grading standards
Level symbol | Acute oral half-lethal dose ( mg/kg) | Acute percutaneous median lethal dose ( mg/kg) | Acute inhalation Lethal concentration ( mg/L) | ||
solid | Liquid 1) | solid | Liquid 1) | Gas and liquefied gas | |
Very toxic | ≤ 5 | ≤ 25 | ≤ 10 | ≤ 50 | ≤ 0.5 |
poisonous | > 5~50 | > 25~200 | > 10～100 | > 50～400 | > 0.5~2 |
harmful | > 50～500 | > 200～2000 | > 100~1000 | > 400～4000 | > 2~20 |
Note: 1) The liquid column of this table includes solid bait or flake pesticide. 2) The gas and liquefied gas columns include powder pesticides with particle diameters not exceeding 50 microns.
4 China's pesticide toxicity grading standards
With reference to international practices, the toxicity classification of pesticides in China is also based on the classification criteria for pesticide hazards recommended by the World Health Organization ( WHO), and takes into account the relevant provisions of previous toxicity classification, combined with the actual situation of pesticide production, use and management in China ( Table 4).
Table 4 Pesticide toxicity grading standards
Toxicity classification | Level symbol | Half-lethal lethal dose ( mg/kg) | Percutaneous half lethal dose ( mg/kg) | Inhaled median lethal concentration ( mg/m 3 ) |
I a level | Very toxic | ≤ 5 | ≤ 20 | ≤ 20 |
I b level | High toxicity | > 5~50 | > 20～200 | > 20～200 |
Level II | Moderate poison | > 50～500 | > 200～2000 | > 200～2000 |
Level III | Low toxicity | > 500～5000 | > 2000～5000 | > 2000～5000 |
Level IV | Microtoxic | > 5000 | > 5000 | > 5000 |
  Â
G70 Eye Slip Lifting Hook,G70 Lifting Hook,G70 Eye Sling Hook,G70 Grab Hook
Shandong Shenli Rigging Co.,LTD. , https://www.liftinghook.nl