Diazinon

MedEd Pesticide lists Diazinon as an insecticide in the organophosphate class.

MedEd Pesticide Summarizes Diazinon at a Glance

Type

Insecticide

Chemical class

Organophosphate

CAS number

333-41-5

Formula

C12H21N2O3PS

Molar mass

304.35 g/mol

EU status

Not approved as an active substance in the EU.

US status

Registered with EPA. 15 active products contain Diazinon.

MedEd Pesticide Summarizes Diazinon’s Toxicity Records

MedEd Pesticide holds 269 toxicity records for Diazinon, from 7 sources. The headline values are below.

Oral LD50 in ratsAcute, swallowed

Lowest reported 66 mg/kg, median 183 mg/kg, from 2 records.

Dermal LD50Acute, skin contact

Lowest reported 180 mg/kg, median 1890 mg/kg, from 2 records.

Lowest NOAELLong term, mammals

0.0037 mg/kg-day in dog, 52 weeks. Source: ToxRefDB.

EPA signal wordsActive US products

Danger 0, Warning 7, Caution 8.

See all 269 Diazinon toxicity records in the explorer. The records come from EPA’s Toxicity Values Database, and the methodology explains their limits.

MedEd Pesticide Reports Diazinon’s EU Safety Reference Values

MedEd Pesticide takes these values from the EU, which sets them when it assesses an active substance. They are expressed per kilogram of body weight.

ADIAcceptable daily intake

0.0002 mg/kg bw/dayThe amount a person can take in every day over a lifetime without appreciable health risk.

ARfDAcute reference dose

0.025 mg/kg bwThe amount that can be taken in over a short period, such as one meal or one day, without appreciable health risk.

AOELAcceptable operator exposure level

0.0002 mg/kg bw/dayThe level of exposure for people who apply the pesticide at which no adverse effect is expected.

MedEd Pesticide Lists Diazinon’s EU Hazard Classification

MedEd Pesticide lists the harmonised EU hazard statements for Diazinon below.

• H302 Harmful if swallowed
• H400 Very toxic to aquatic life
• H410 Very toxic to aquatic life with long-lasting effects

MedEd Pesticide takes EU status, reference values and hazard classification from the EU Pesticides Database. MedEd Pesticide takes US status from EPA’s Pesticide Product Information System (dated 2026-10-13) and chemical identity from PubChem. Retrieved 2026-10-16. Values and approvals change, so check the source for the current entry. See the methodology and the glossary, or compare Diazinon with another pesticide.

MedEd Pesticide. (2026). Diazinon. https://mededpesticide.org/pesticides/diazinon/ (accessed Month Day, Year)