Chlorpyrifos
CAS NO.: 2921-88-2
Chlorpyrifos is a crystalline organophosphate insecticide. Introduced in 1965 by Dow Chemical Company, it is known by many trade names including Dursban and Lorsban. It acts on the nervous system of insects by inhibiting acetylcholinesterase.
Function
The crops with the most intense chlorpyrifos use are cotton, corn, almonds, and fruit trees includingoranges, bananas and apples
| Crop | Pests | Rate of Use | Application |
| Citrus | Red spider | 320-480 mg/kg | Spray |
| Apple trees | Woolly aphid | 200-240 mg/kg | |
| Brassicaceous vegetable | Cabbage caterpillar | 450-542 g/ha. | |
| Rice | Rice leaf folder | 450-600 g/ha. | |
| Rice | Rice planthopper | 468-612 g/ha. |
Note
1. Chlorpyrifos is moderately toxic to humans. Chronic exposure has been linked to neurological effects, developmental disorders, and autoimmune disorders. Exposure during pregnancy retards the mental development of children, and most use in homes has been banned since 2001 in the U.S.
2. As a chemical for farming use, it remains "one of the most widely used organophosphate insecticides", according to the United States Environmental Protection Agency (EPA).
3. This farm chemical is highly toxic to amphibians. A recent study by the United States Geological Survey found that its main breakdown product in the environment, chlorpyrifos oxon, is even more toxic to these animals.
4. The insect killer is very toxic for aquaculture fish and bees.
Technical Parameters
1. Chlopyrifos 48% EC| Testing Items | Standards | Method |
| Appearance | Light-yellow clear liquid | N/A |
| Effective Acid, g/L | ≥480.0 | CIPAC Handbook 1C, 221.b/TC/M/3 |
| PH Value | 4.5~6.5 | MT75 CIPAC 1970 Vol. I p. 1008 |
| Moisture, % | ≤0.3 | MT 30-1 CIPAC 1970 Vol. I |
| Persistent Foam, after 1 min | ＜20mL | MT 47.2, CIPAC Handbook F, p. 52, 1995 |
| Storage Stability at Low Temperature (0℃) | FAO | MT 39.3 CIPAC J, p. 126, 2000 |
| Storage Stability at High Temperature (54℃) | FAO | MT 46.1.1, CIPAC F, p.149 |
| Emulsion Stability | FAO | MT 36.1.1, CIPAC 1, p.910 |
| Items | Specification | Method |
| Appearance | Off-white flowable liquid | N/A |
| Purity, % | ≥ 40.0 | HPLC |
| PH Value | -- | CIPAC MT 75.3 |
| Persistent Foaming, ml | Maximum 60ml after 1 minute | CIPAC MT 47.2 |
| Water, % | ≤25.0 | Karl Fischer |
| Storage Stability at 0℃ | Comply with above | CIPAC MT 39.1 |
| Storage Stability at 54℃ | Comply with above | CIPAC MT 46.3 |
