Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Ioxynil

Ioxynil is a colorless crystalline solid with a faint phenolic odor.

CAS 1689-83-4 C7H3I2NO 370.91 g/mol Danger

01 · Identification

What Ioxynil is

Ioxynil is a colorless crystalline solid with a faint phenolic odor. Its molecular formula is C7H3I2NO and its molecular weight is 370.91 g/mol. It melts at 200 °C.

Under the GHS it carries the signal word Danger.

02 · Identifiers

Ioxynil identifiers and molecular data

Ioxynil CAS number and EC number

CAS number1689-83-4
EC number216-881-1
Index number (CLP Annex VI)608-007-00-6

Ioxynil molecular formula and molecular weight

Molecular formulaC7H3I2NO
Molecular weight370.91 g/mol

Other names for Ioxynil

  • ioxynil (ISO)
  • 4-hydroxy-3,5-diiodobenzonitrile

03 · GHS classification

Ioxynil hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Ioxynil pictograms and signal word

Signal wordDanger

Ioxynil hazard class and category

GHS hazard classes Ioxynil falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 3 H301 GHS06
Acute toxicity - dermal GHS chapter 3.1 Category 4 H312 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 3 H331 GHS06
Serious eye damage/eye irritation GHS chapter 3.3 Category 2A H319 GHS07
Specific target organ toxicity - repeated exposure GHS chapter 3.9 Category 2 H373 GHS08
Hazardous to the aquatic environment - acute GHS chapter 4.1 Category 1 H400 GHS09
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 1 H410 GHS09

Ioxynil hazard statements (H-codes)

Hazard statements assigned to Ioxynil
CodeHazard statement
H361d Suspected of damaging the unborn child.
H331 Toxic if inhaled.
H301 Toxic if swallowed.
H312 Harmful in contact with skin.
H373 May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H319 Causes serious eye irritation.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to Ioxynil. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Ioxynil

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Ioxynil issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Ioxynil precautionary statements

CLP Annex VI assigns 20 precautionary statements to Ioxynil. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Disposal

What has to happen to the contents and the empty container.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Ioxynil name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български йоксинил (ISO) 4-хидрокси-3,5-дийодобензонитрил
Spanish español Yoxinilo (ISO) 4-hidroxi-3,5-diyodobenzonitrilo
Czech čeština ioxynil (ISO) 4-hydroxy-3,5-dijodbenzonitril
Danish dansk ioxynil (ISO) 4-hydroxy-3,5-diiodbenzonitril
German Deutsch Ioxynil (ISO) 4-Hydroxy-3,5-diiodbenzonitril
Estonian eesti joksüniil (ISO) 4-hüdroksü-3,5-dijodobensonitriil
Greek ελληνικά ioxynil (ιωξυνίλη) (ISO) 4-υδροξυ-3,5-διιωδοβενζονιτρίλιο
English English ioxynil (ISO) 4-hydroxy-3,5-diiodobenzonitrile
French français ioxynil (ISO) 4-hydroxy-3,5-diiodobenzonitrile
Croatian hrvatski joksinil (ISO) 4-hidroksi-3,5-dijodbenzonitril
Italian italiano ioxinil (ISO) 4-idrossi-3,5-diiodobenzonitrile
Latvian latviešu joksinils (ISO) 4-hidroksi-3,5-dijodbenzonitrils
Lithuanian lietuvių joksinilas (ISO) 4-hidroksi-3,5-dijodbenznitrilas
Hungarian magyar ioxinil (ISO) 4-hidroxi-3,5-dijódbenzonitril
Maltese Malti jossinil (ISO) 4-idrossi-3,5-diiodobenżonitril
Dutch Nederlands ioxynil (ISO) 4-hydroxy-3,5-diiodobenzonitril
Polish polski joksynyl (ISO) 4-hydroksy-3,5-dijodobenzonitryl
Portuguese português ioxinil (ISO) 4-hidroxi-3,5-diiodobenzonitrilo
Romanian română ioxinil(ISO) 4-hidroxi-3,5-diiodobenzonitril
Slovak slovenčina joxynil (ISO) 4-hydroxy-3,5-dijódbenzonitril
Slovenian slovenščina joksinil (ISO) 4-hidroksi-3,5-dijodobenzonitril
Finnish suomi ioksiniili (ISO) 4-hydroksi-3,5-dijodibentsonitriili
Swedish svenska ioxinil (ISO) 4-hydroxi-3,5-dijodbensonitril

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Ioxynil GHS label elements

Everything CLP Annex VI fixes for Ioxynil, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS06 Skull and crossbones pictogramGHS08 Health hazard pictogramGHS09 Environment pictogram

Danger

Ioxynil

  • Suspected of damaging the unborn child.
  • Toxic if inhaled.
  • Toxic if swallowed.
  • Harmful in contact with skin.
  • May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Causes serious eye irritation.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Wash thoroughly after handling.
  • Do not eat, drink or smoke when using this product.
  • Use only outdoors or in a well-ventilated area.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF INHALED:
  • IF IN EYES:
  • Immediately call a POISON CENTER/doctor/
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Get medical advice/attention if you feel unwell.
  • Rinse mouth.
  • If eye irritation persists:
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Wash with plenty of water/
  • Collect spillage.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Ioxynil in the GHS label constructor →

07 · Health hazards

Ioxynil health hazards and exposure limits

Ioxynil hazard summary

A mild skin and eye irritant; Can be absorbed through skin; May be a developmental toxin, based on animal studies; [ICSC] In acute poisoning, workers had vomiting, increase in body temperature, excessive perspiration, elevated thiocyanate in urine, and abnormal liver enzymes; No adverse effects were observed in 90-day 111 ppm oral study with rats; Inhibited oxidative phosphorylation in rat liver mitochondria; [HSDB] See Benzonitrile.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

Ioxynil occupational exposure limits

US occupational exposure limits reported for Ioxynil. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL 5.0 [mg/m3], as CN Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.

08 · Physical and chemical properties

Ioxynil properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Ioxynil boiling point

Property Value Conditions Source
Boiling point 140 °C (284 °F) sublimes, at 0.1 mmHg (reduced pressure) HSDB

Ioxynil melting point

Property Value Conditions Source
Melting point 200 °C (392 °F) TECHNICAL PRODUCT HSDB
212.5 °C (414.5 °F) range, midpoint shown HSDB

Ioxynil solubility

Property Value Conditions Source
Solubility SOLUBILITY IN WATER @ 20-25 °C: 22%; 14%; 10.7% LITHIUM SALT HSDB
SLIGHTLY SOL IN CHLOROFORM; SOL IN ETHER HSDB
SOLUBILITY IN WATER: 0.005% @ 20 °C; IN CYCLOHEXANONE: 14%; IN DIMETHYLFORMAMIDE: 74% at 20 °C HSDB

Ioxynil vapor pressure

Property Value Conditions Source
Vapor pressure 0.0000277 mmHg at 105 °C HSDB
7501 mmHg below this value, at 20 °C HSDB
1.4e-7 mmHg Haz-Map

Ioxynil corrosivity

Property Value Conditions Source
Corrosivity Non-corrosive HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Handling and storage

Ioxynil storage and handling

Ioxynil safe storage

Provision to contain effluent from fire extinguishing. Separated from strong oxidants and food and feedstuffs.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

Planning storage for a mix of chemicals? Check Ioxynil in the storage compatibility matrix →

10 · Questions

Ioxynil — frequently asked questions

What is the CAS number of Ioxynil?

The CAS number of Ioxynil is 1689-83-4. Its EC number is 216-881-1.

What is the chemical formula of Ioxynil?

The molecular formula of Ioxynil is C7H3I2NO and its molecular weight is 370.91 g/mol.

What does a Ioxynil label have to show?

Under CLP Annex VI the label for Ioxynil carries the pictograms Skull and crossbones, Health hazard and Environment and the signal word is Danger.

Is Ioxynil flammable?

CLP Annex VI assigns Ioxynil no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.

Is Ioxynil a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Ioxynil. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the exposure limit for Ioxynil?

The US occupational exposure limit reported for Ioxynil is 5.0 [mg/m3], as CN (Haz-Map, Information on Hazardous Chemicals and Occupational Diseases). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.

What is the boiling point of Ioxynil?

The boiling point reported for Ioxynil is 140 °C (284 °F), sublimes, at 0.1 mmHg (reduced pressure) (HSDB).

What is the melting point of Ioxynil?

The melting point reported for Ioxynil is 200 °C (392 °F), TECHNICAL PRODUCT (HSDB).

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