UN/NA Number Reference
DOT Class 6.1 Toxic Substance placard

UN 1704: Tetraethyl dithiopyrophosphate

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1704 is assigned the proper shipping name Tetraethyl dithiopyrophosphate in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 6.1 Toxic Substance material, Packing Group II. Required label(s): 6.1.

Packing group indicates the degree of danger within a hazard class: PG I is high danger, PG II medium, PG III low. The proper shipping name, hazard class, UN number, and packing group together form the basic shipping description that must appear on shipping papers and, where required, on the package and placard.

Emergency Response (ERG Guide 153)

Hazards: TOXIC. Combustible. Corrosive. Causes burns. Toxic fumes when heated.

Fire: Small: dry chemical, CO2, water spray. Large: water spray, foam.

Spill: Do not touch. Stop leak if safe. Use water spray to reduce vapor.

Chemical and Physical Properties

Tetraethyl dithiopyrophosphate is an organic phosphate pesticide which acts as an inhibitor of cholinesterase, and as such it is highly toxic by all routes of exposure. It is a colorless to pale yellow mobile oil with an odor of garlic. It may be found as a liquid or as a dry mixture where the liquid is absorbed onto a dry carrier.

CAS Number: 3689-24-5
Molecular Formula: C8H20O5P2S2
Molecular Weight: 322.3 g/mol
Color / Form: COLORLESS OIL
Odor: Possesses a garlic odor
Boiling Point: 277 to 282 F
Flash Point: Not combustible (EPA, 1998)
Specific Gravity: 1.196 (sinks in water)
Vapor Pressure: 0.00017 mmHg at 68 F
Water Solubility: less than 0.1 mg/mL at 64 F
Log P: log Kow = 3.99

Regulatory Data

CERCLA RQ (40 CFR 302.4)
100 lb
EPCRA TPQ (40 CFR 355)
500 lb
OSHA PEL
TWA 0.2 mg/m 3 [skin]
NIOSH REL
TWA 0.2 mg/m 3 [skin]
IDLH
10 mg/m 3
RCRA Waste Code(s)
[object Object], [object Object]

A release of this material at or above its CERCLA reportable quantity (100 lb) requires immediate notification to the National Response Center at 800-424-8802.

Special Provisions

49 CFR 172.102 special provision codes for this entry: IB2, T7, TP2. These codes modify the general requirements (packaging, quantity limits, exceptions) for this specific material. Look up each code in 49 CFR 172.102 for the full text.

Need the full interactive record? Open UN 1704 in the SpillNerd lookup tool for the live database entry with placard graphics, GHS pictograms, full segregation tables, and synonym search. For another material, use the UN number and chemical lookup.

Reference data compiled from the DOT Hazardous Materials Table (49 CFR 172.101), the 2024 Emergency Response Guidebook, and public chemical databases (PubChem, NIOSH, EPA). Always verify the correct shipping description against the current regulation and the manufacturer's SDS Section 14 before shipping.