Molecular Formula | C10H19O6PS2 |
Molar Mass | 330.36 |
Density | 1.2076 |
Melting Point | 2.85°C |
Boling Point | 156°C |
Flash Point | -18°C |
Water Solubility | 0.0145 g/100 mL |
Solubility | Slightly soluble in water, miscible with acetone, with cyclohexane, with ethanol (96 per cent) and with vegetable oils. |
Vapor Presure | 7.95 at 25 °C (gas saturation method-GC, Kim et al., 1984) |
Appearance | liquid |
Specific Gravity | 1.23 (25℃) |
Exposure Limit | NIOSH REL: TWA 10 mg/m3, IDLH 250 mg/m3; OSHA PEL: TWA15 mg/m3; ACGIH TLV: TWA 10 mg/m3. |
Storage Condition | APPROX 4°C |
Stability | Stable. Incompatible with oxidizing agents, metals. |
Refractive Index | nD25 1.4985 |
Physical and Chemical Properties | Density 1.2076 melting point 2.85°C boiling point 156°C water solubility 0.0145g/100 mL |
Use | Is a low toxicity of non-systemic insecticide, acaricide, widely used in agriculture and horticulture, can also be used as a family health medication |
Risk Codes | R22 - Harmful if swallowed R50/53 - Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. R67 - Vapors may cause drowsiness and dizziness R65 - Harmful: May cause lung damage if swallowed R38 - Irritating to the skin R11 - Highly Flammable R43 - May cause sensitization by skin contact |
Safety Description | S2 - Keep out of the reach of children. S24 - Avoid contact with skin. S60 - This material and its container must be disposed of as hazardous waste. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. S62 - If swallowed, do not induce vomitting; seek medical advice immediately and show this container or label. S46 - If swallowed, seek medical advice immediately and show this container or label. S37 - Wear suitable gloves. S16 - Keep away from sources of ignition. |
UN IDs | UN 2783 |
RTECS | WM8400000 |
HS Code | 29309090 |
Hazard Class | 6.1(b) |
Packing Group | III |
Toxicity | LD50 in female, male rats (mg/kg): 1000, 1375 orally (Gaines) |
Henry's Law Constant | (x 10-9 atm?m3/mol):4.89 at 25 °C (wetted-wall column, Fendinger and Glotfelty, 1990) |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
(IARC) carcinogen classification | 2A (vol. 30, sup 7, 112) 2017 |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
original drug | malathion, also known as marathon, English malathion, molecular formula C10H19O6PS2, pure product is colorless or light oily liquid at room temperature, with garlic smell, industrial product with dark brown and strong smell. Low volatility, melting point 2.85 ℃. Slightly soluble in water, miscible with most organic solvents. Unstable, it is easy to hydrolyze and fail when the PH is below 5.0 and above pH 7.0, and it decomposes rapidly when the PH is above 12, which can also promote the decomposition of iron, aluminum and metal. Unstable to light and heat. Malathion has good contact and certain fumigation, non-systemic insecticide and acaricide. After entering the insect body, it is oxidized into malafoxine, which can play a more toxic role. When entering warm-blooded animals, it is hydrolyzed by carboxylesterase that is not in the insect body, thus losing its toxicity. Malathion has low toxicity, short residual effect period, and is effective against both pricking mouthpart and chewing mouthpart pests. It is suitable for controlling Lepidoptera, Coleoptera and other insects on crops such as tobacco, rice, cotton, soybeans, vegetables, fruit trees, trees, tea and mulberry. It can also be used to control warehouse pests. |
usage | 1. control of wheat crop pests control armyworms, aphids and wheat leaf bees, spray with 1000 times of 45% emulsifiable concentrate. 2. Prevention and control of legume crop pests. Soybean heartworms, soybean bridge-building insects, pea elephants, peas, tube aphids, and yellow striped jumpers are sprayed with 1000 times of 45% emulsifiable concentrate, and the spray volume per mu is 75-100kg. 3. Control of rice pests Control of rice leafhoppers and rice planthoppers, spray with 1000 times of 45% emulsifiable concentrate, spray 75-100kg per mu 4. Control of cotton pests Control of cotton leaf jumping insects, blind bugs, spray with 1500 times of 45% emulsifiable concentrate. 5. Prevention and control of fruit tree pests All kinds of spiny moths, nest moths, powder scale insects and aphids on fruit trees are sprayed with 1500 times of 45% emulsifiable concentrate. 6. Prevention and control of tea tree pests. Tea weevil, long white mealybug, turtle shell mealybug, tea cotton mealybug, etc. are sprayed with 500-800 times of 45% emulsifiable concentrate. 7. Control of vegetable pests Prevention and control of Pieris rapae, aphid, yellow striped beetle, etc., spray with 1000 times of 45% emulsifiable concentrate. 8. Prevention and control of forest pests, such as inchworm, pine caterpillar, poplar moth, etc., 150-200 ml of 25% oil per mu, ultra-low capacity spray. 9. Control of Health Pests Flies Use 250 times of 45% EC as 100-200 ml/m2. Bedbugs should be treated with 160 times of 45% emulsifiable concentrate at 100-150 ml/m2. Cockroaches are treated with 250 times of 45% emulsifiable concentrate at 50 ml/m2. |
organophosphorus insecticide | parathion, methyl parathion, methamidophos, acephate, isocarbophos, carol, dimethoate, omethoate, internal phosphorus absorption, dichlorvos, malathion, phoxphos, monocrotophos, chlorpyrifos, triazofos, methyl isosphos, trichlorfons, furfurfurs, triphons, triphons, triphons, triphons, phons, f, control of phosphorus (Suhua 203), isopropyl. The main species is chlorpyrifos. At present, the biggest bottleneck restricting the production and development of chlorpyrifos in China is not overcapacity but a large amount of salt-containing wastewater that is difficult to treat during the synthesis of its special intermediate sodium trichloropyridinol. Therefore, the focus of future development will be It is to synthesize sodium trichloropyridinol through the hydrolysis and acidification route of tetrachloropyridine. |
toxicity | acute oral LD50 of male rats is 1634 mg/kg, female is 1751.5 mg/kg; The acute percutaneous LD50 of rats is 4000~6150 mg/kg, and the acute percutaneous LD50 of rabbits is 4100 mg/kg (contact 24 hours). It has a stimulating effect on the eyes and skin. After feeding rats with industrial products containing 0.1% lathion in the feed for 2 years, their weight increased normally. LC50 to carp is 9.0mg/L(48h), which is highly toxic to bees. |
use | low toxicity, broad spectrum insecticide and acaricide. It has the effects of contact killing, stomach poison, weak fumigation, and no absorption. Due to its strong killing power, rapid action and long-term use, many pests have developed resistance. It can be used to control rice, wheat, cotton, vegetables, tea, fruit tree pests, such as aphids, rice planthoppers, rice leafhoppers, rice thrips, rice borers, scale insects, red spiders, golden crustaceans, leaf traps, leaf jumping Insect, cotton leaf curl, armyworm, vegetable borer, tea green leafhopper, fruit tree heartworm. It can be used for hygiene to kill mosquitoes, fly larvae and bed bugs, and can also be used for food pests. Malathion is a high-efficiency and low-toxicity insecticide and acaricide with a wide range of control. Not only used in rice, wheat, cotton, and because of low toxicity, short residual effect, but also used in vegetables, fruit trees, tea, and warehouse insect control. Mainly control rice planthoppers, rice leafhoppers, cotton aphids, cotton red spiders, wheat armyworms, pea elephants, soybean heartworms, fruit tree red spiders, aphids, powder scale insects, nest moths, vegetable yellow striped jumps, vegetable leaf insects, A variety of scales on tea trees, as well as mosquitoes, fly larvae and bed bugs. It is a low-toxic non-systemic insecticide and acaricide. It is widely used in agriculture and gardening. It can also be used as a household hygiene drug. Pesticide residue analysis standard. Pesticide. |
Production method | Synthesis of dimethyl dithiophosphate from phosphorus pentasulfide and methanol, and then addition with diethyl maleic acid to obtain malathion. Diethyl maleate (380kg in 100%) is put into a 1000L glass-lined reaction pot for stirring, the temperature is controlled below 45 ℃, and 350kg of phosphorus pentasulfide is put into the pot. Slowly add methanol dropwise, control the temperature to 48-55 ℃, and add 250kg of methanol in about 2 hours. After addition, keep 65-75 ℃ for 8h. The reaction produces hydrogen sulfide and escapes methanol vapor. The methanol is refluxed through the condenser, and the hydrogen sulfide is absorbed by lye. This process is carried out under negative pressure. After the reaction is completed, cool to 40-50°C, and let it stand and delaminate to precipitate impurities. The upper crude oil is successively washed with water, alkali and water, and then dehydrated in a vacuum dehydration pot. The water in the crude oil is evaporated for 1.5-2h below 85 ℃ (vacuum degree 93.3kPa) to obtain malathion crude oil. Raw material consumption quota: maleic anhydride 430kg/t, phosphorus pentasulfide 470kg/t, ethanol 420kg/t, methanol 390kg/t. Esterification consists of maleic acid (or anhydride) and ethanol catalyzed by sulfuric acid to generate diethyl maleic acid. Benzene is used as solvent, and benzene, ethanol, and water are used for azeotropic dehydration to facilitate the esterification reaction. Synthesis of O,O-dimethyldithiophosphoric acid (see the preparation method of dimethoate for details) and diethyl maleate are added to obtain malathion. The ratio of O,O-dimethylthiophosphoric acid to diethyl maleic acid is 1:1.15, the reaction temperature is 55 ≤ 70 ℃, and the reaction time is about 7h. |
category | pesticide |
toxicity classification | highly toxic |
acute toxicity | oral-rat LD50: 290 mg/kg; Oral-mouse LD50:190 mg/kg |
flammability hazard characteristics | open flame is combustible; heat decomposes toxic phosphorus oxide and sulfur oxide gas |
storage and transportation characteristics | warehouse ventilation and low temperature drying; Store separately from oxidants and food additives |
fire extinguishing agent | water, foam, carbon dioxide, sand. |
occupational standard | TWA 10 mg/m3; STEL 20 mg/m3 |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |
immediate life-threatening and health concentration | 250 mg/m3 |