Is sulfur dioxide dangerous to humans?

Yes, in high concentrations it is toxic and irritates the respiratory system. Long-term exposure is linked to respiratory illnesses.

Why is sulfur dioxide used in food?

It acts as a preservative (E220) to prevent browning and spoilage in dried fruits, wine, and some processed foods, though it can cause allergic reactions in some people.

What's the difference between sulfur dioxide and sulfites?

Sulfites are salts derived from sulfurous acid (containing the sulfite ion SO₃²⁻). Sulfur dioxide (SO₂) is the gaseous form, which can dissolve in water to form sulfites. On food labels, 'sulfites' often refer to these preservative compounds.

How can sulfur dioxide emissions be reduced?

Through technology like flue-gas desulfurization (scrubbers) in power plants, using low-sulfur fuels, and industrial process changes.

Is “sulfur dioxide” formal?

Sulfur dioxide is usually technical / scientific / environmental / industrial in register.

How do you pronounce “sulfur dioxide”?

Sulfur dioxide: in British English it is pronounced /ˌsʌlfə daɪˈɒksaɪd/, and in American English it is pronounced /ˌsʌlfər daɪˈɑːksaɪd/. Tap the audio buttons above to hear it.

sulfur dioxide: meaning, definition, pronunciation and examples

UK/ˌsʌlfə daɪˈɒksaɪd/US/ˌsʌlfər daɪˈɑːksaɪd/

Technical / Scientific / Environmental / Industrial

My Flashcards

Quick answer

What does “sulfur dioxide” mean?

A toxic gas with the formula SO₂, produced by burning sulfur or certain fossil fuels.

Audio

Pronunciation

Definition

Meaning and Definition

A toxic gas with the formula SO₂, produced by burning sulfur or certain fossil fuels.

A pungent, colorless gas that is a major air pollutant, causing acid rain and respiratory problems, also used as a preservative and disinfectant in food and winemaking.

Dialectal Variation

British vs American Usage

Differences

The spelling: 'sulphur dioxide' (UK) vs. 'sulfur dioxide' (US). The chemical element itself is spelled 'sulphur' (UK) and 'sulfur' (US).

Connotations

Identical in both variants: negative connotations related to pollution and industrial harm, or neutral in precise scientific/industrial contexts.

Frequency

Equal frequency in relevant technical and environmental discourses in both regions.

Grammar

How to Use “sulfur dioxide” in a Sentence

[Factory/Volcano] emits sulfur dioxide.Sulfur dioxide is released by [process].[Regulation] limits sulfur dioxide.[Substance] contains sulfur dioxide as a preservative.

Vocabulary

Collocations

strong

emit sulfur dioxidesulfur dioxide emissionslevels of sulfur dioxideconcentration of sulfur dioxidereduce sulfur dioxide

medium

release sulfur dioxidesulfur dioxide pollutioncontain sulfur dioxidemeasure sulfur dioxideexposure to sulfur dioxide

weak

produce sulfur dioxidesulfur dioxide gashigh sulfur dioxidesulfur dioxide fromsulfur dioxide in the atmosphere

Examples

Examples of “sulfur dioxide” in a Sentence

verb

British English

The process will sulphurate the ore, releasing sulphur dioxide.
The new scrubbers are designed to desulphurise the flue gas.

American English

The plant must sulfurize the compound under controlled conditions.
The technology effectively desulfurizes the emissions.

adverb

British English

Not typically used as an adverb.

American English

Not typically used as an adverb.

adjective

British English

Sulphur-dioxide-laden air hung over the city.
The sulphur-dioxide emission limits were tightened.

American English

Sulfur-dioxide-rich plumes rose from the volcano.
A new sulfur-dioxide monitoring station was installed.

Usage

Meaning in Context

Business

Discussed in reports on environmental compliance, emissions trading, and corporate sustainability.

Academic

A key subject in chemistry, environmental science, atmospheric studies, and public health research.

Everyday

Mentioned in news about pollution, air quality alerts, or occasionally on food labels (e.g., 'contains sulfites').

Technical

Precise measurements, industrial process controls, regulatory standards, and chemical analysis.

Vocabulary

Synonyms of “sulfur dioxide”

Strong

sulfurous anhydride (technical)

Neutral

SO₂ (the chemical formula)sulphur dioxide (UK spelling)

Weak

pollutant (general)acid gas (descriptive)

Vocabulary

Antonyms of “sulfur dioxide”

clean airfresh airunpolluted atmosphere

Watch out

Common Mistakes When Using “sulfur dioxide”

Misspelling: 'sulphur' (US) or 'sulfur' (UK) in the wrong variety.
Incorrect plural: 'sulfur dioxides' (usually uncountable; the plural refers to multiple instances/types of emissions).
Confusing with carbon dioxide (CO₂) due to similar word structure.

FAQ

Frequently Asked Questions

: Yes, in high concentrations it is toxic and irritates the respiratory system. Long-term exposure is linked to respiratory illnesses.
: It acts as a preservative (E220) to prevent browning and spoilage in dried fruits, wine, and some processed foods, though it can cause allergic reactions in some people.
: Sulfites are salts derived from sulfurous acid (containing the sulfite ion SO₃²⁻). Sulfur dioxide (SO₂) is the gaseous form, which can dissolve in water to form sulfites. On food labels, 'sulfites' often refer to these preservative compounds.
: Through technology like flue-gas desulfurization (scrubbers) in power plants, using low-sulfur fuels, and industrial process changes.
: A toxic gas with the formula SO₂, produced by burning sulfur or certain fossil fuels.
: Sulfur dioxide is usually technical / scientific / environmental / industrial in register.
: Sulfur dioxide: in British English it is pronounced /ˌsʌlfə daɪˈɒksaɪd/, and in American English it is pronounced /ˌsʌlfər daɪˈɑːksaɪd/. Tap the audio buttons above to hear it.

Phrases

Idioms & Phrases

“None. It is a technical compound noun, not used idiomatically.”

Learning

Memory Aids

Mnemonic

Think: SULfur DIOxide = SO₂. The 'DI' in dioxide reminds you there are TWO oxygen atoms (O₂) attached to one Sulfur (S) atom.

Conceptual Metaphor

POLLUTION IS A POISON / INDUSTRY'S BREATH (e.g., 'The plant belched sulfur dioxide into the sky.')

Practice

Quiz

Fill in the gap

The primary source of anthropogenic is the combustion of fossil fuels containing sulfur.

Multiple Choice

What is the primary environmental impact of excessive sulfur dioxide emissions?