---
title: "Dihydrogen monoxide parody"
chunk: 1/2
source: "https://en.wikipedia.org/wiki/Dihydrogen_monoxide_parody"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:26:44.581138+00:00"
instance: "kb-cron"
---

The dihydrogen monoxide parody involves referring to water (H2O) by its unfamiliar chemical systematic name "dihydrogen monoxide" (DHMO) and describing some properties of water in a particularly concerning manner – such as its ability to accelerate corrosion (rust) and cause suffocation (drowning) – often calling for it to be banned, regulated strictly, or labeled as a hazardous chemical. 
The motivation behind the parody is to play into chemophobia, and to demonstrate how exaggerated analysis, information overload, and a lack of scientific literacy can lead to misplaced fears.
Occasionally, reports also reference its widespread contamination of rivers or municipal water supplies. The parody has also involved other uncommon chemical nomenclatures for water such as "hydrogen hydroxide", "dihydrogen oxide" and "hydric acid".

== History ==
In 1983, on April Fools' Day, an edition of the Durand Express, a weekly newspaper in Durand, Michigan, reported that "dihydrogen oxide" had been found in the city's water pipes, and warned that it was fatal if inhaled, and could produce blistering vapors.
The first appearance of the parody as "dihydrogen monoxide" on the Internet was attributed to the "Coalition to Ban Dihydrogen Monoxide", a parody organization at the University of California, Santa Cruz following on-campus postings and newsgroup discussions in 1990. This new version of the parody was created by housemates while attending UC Santa Cruz, in 1990, revised by Craig Jackson in 1994, and was published in Analog Science Fiction and Fact in March 1996. It received widespread public attention in 1997 when Nathan Zohner, a 14-year-old student, gathered petitions to ban "DHMO" as the basis of his science project, titled "How Gullible Are We?"
Jackson's original site included the following warning:

A mock material safety data sheet has also been created for DHMO.

== Molecular terminology and naming conventions ==
The water molecule has the chemical formula H2O, meaning the molecule is composed of two hydrogen atoms and one oxygen atom. Literally, the term "dihydrogen monoxide" means "two hydrogen, one oxygen": the prefix di- in dihydrogen means "two", the prefix mono- in monoxide means "one", and "oxide" designates oxygen in a compound (the consecutive o's that would occur in "monooxide" are combined into one).
Using chemical nomenclature, other names for water include hydrogen oxide, hydrogen hydroxide, which characterises it as a base, and several designating it as an acid, such as hydric acid or hydroxyl acid. The term used in the original text, hydroxyl acid, is a non-standard name.
Under the 2005 revisions of IUPAC nomenclature of inorganic chemistry, there is no single correct name for every compound. The primary function of chemical nomenclature is to ensure that each name refers, unambiguously, to a single substance. It is considered less important to ensure that each substance should have a single unambiguous name, although the number of acceptable names is limited. Water is one acceptable name for this compound, even though it is neither a systematic nor an international name and is specific to just one phase of the compound (its liquid form). The other IUPAC recommendation is oxidane.

== Public use ==