Acetaldehyde

from source

C2H4O · 44.05 g/mol

acetic aldehyde · ethanal · ethyl aldehyde · Acetic ethanol

What is Acetaldehyde?

What alcohol first turns into as the body breaks it down, and a large part of a hangover. Acetaldehyde (C2H4O, 44 g/mol) is an aldehyde found in everyday food and flavor. Found in coffee, wine, beer, and spirits. from source

CategoryFood & flavor

Chemical familyAldehydes

LeaderboardsBiggest Deadliest

Fig. 1 · 2D structure RDKit

SMILESCC=O

Where you'll find it

Coffeewhat else is in it →Winewhat else is in it →Beerwhat else is in it →Spiritswhat else is in it →

Curated by MoleculeFinder from source

The dose makes the poison inferred

A reported rat oral LD50 for Acetaldehyde is 661 mg/kg, the dose lethal to half the animals tested. Scaled by body mass alone:

your weight154 lb

46.3 g

a median lethal dose scaled to 154 lb (46,270 mg)

“The dose makes the poison” is a cross-species estimate shown as neutral science, not a threshold anyone should act on. Real toxicity depends on the person, not body mass alone.

Toxicity & hazards

Toxicity · LD50

661 mg/kg · low toxicity · LD50 rat oral from source

The dose lens above scales this to a body weight.

6 more reported values

1,930 mg/kgLD50 · oral · rat
212 mg/kgLD50 · iv · mouse
500 mg/kgLD50 · other · mouse
560 mg/kgLD50 · other · mouse
640 mg/kgLD50 · other · rat
3,540 mg/kgLD50 · dermal · rabbit

DangerFlammableToxicIrritantHealth hazardH224, H302, H311, H315, H317, H319, H332, H335, H336, H341, H350, H351, H360, H361, H370, H372, H402from source

Compare with

Acetaldehyde vs Formaldehyde

Sources & methodology

PubChem CID: 177
Wikidata: Q61457
Structure: PubChem → RDKit
LD50: PubChem
Everyday relationships: MoleculeFinder editorial curation
Data refreshed: October 19, 2026

How MoleculeFinder sources and labels its data