Substance profile
1-Naphthol
1-Naphthol is yellow monoclinic needles from water with a phenolic odor.
01 · Identification
What 1-Naphthol is
1-Naphthol is yellow monoclinic needles from water with a phenolic odor. Its molecular formula is C10H8O and its molecular weight is 144.17 g/mol. It boils at 288 °C, melts at 96 °C.
Under the GHS it carries the signal word Danger.
02 · Identifiers
1-Naphthol identifiers and molecular data
1-Naphthol CAS number and EC number
1-Naphthol molecular formula and molecular weight
Other names for 1-Naphthol
- 1-naphtol
03 · GHS classification
1-Naphthol hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
1-Naphthol pictograms and signal word
1-Naphthol hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Acute toxicity - oral GHS chapter 3.1 | Category 4 | H302 | GHS07 |
| Acute toxicity - dermal GHS chapter 3.1 | Category 4 | H312 | GHS07 |
| Skin corrosion/irritation GHS chapter 3.2 | Category 2 | H315 | GHS07 |
| Serious eye damage/eye irritation GHS chapter 3.3 | Category 1 | H318 | GHS05 |
| Specific target organ toxicity - single exposure GHS chapter 3.8 | Category 3 | H335 | GHS07 |
1-Naphthol hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H312 | Harmful in contact with skin. |
| H302 | Harmful if swallowed. |
| H335 | May cause respiratory irritation. |
| H315 | Causes skin irritation. |
| H318 | Causes serious eye damage. |
This page lists only the codes assigned to 1-Naphthol. 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 1-Naphthol
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 1-Naphthol 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
1-Naphthol precautionary statements
CLP Annex VI assigns 13 precautionary statements to 1-Naphthol. 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.
Prevention
What to do before and during handling so the hazard never happens.
Response
What to do once exposure, spillage or fire has already happened.
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
1-Naphthol 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 | 1-нафтол |
| Spanish español | 1-Naftol |
| Czech čeština | 1-naftol |
| Danish dansk | 1-naphtol |
| German Deutsch | 1-Naphtol |
| Estonian eesti | 1-naftool |
| Greek ελληνικά | 1-ναφθόλη |
| English English | 1-naphtol |
| French français | 1-naphtol |
| Croatian hrvatski | 1-naftol |
| Italian italiano | 1-naftolo |
| Latvian latviešu | 1-naftols |
| Lithuanian lietuvių | 1-naftolis |
| Hungarian magyar | 1-naftol |
| Maltese Malti | 1-naftol |
| Dutch Nederlands | 1-naftol |
| Polish polski | 1-naftol 1-hydroksynaftalen |
| Portuguese português | 1-naftol |
| Romanian română | 1-naftol |
| Slovak slovenčina | 1-naftol |
| Slovenian slovenščina | 1-naftol |
| Finnish suomi | 1-naftoli |
| Swedish svenska | 1-naftol |
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
1-Naphthol GHS label elements
Everything CLP Annex VI fixes for 1-Naphthol, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
1-Naphthol
- Harmful in contact with skin.
- Harmful if swallowed.
- May cause respiratory irritation.
- Causes skin irritation.
- Causes serious eye damage.
- Wash … thoroughly after handling.
- Do not eat, drink or smoke when using this product.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF ON SKIN:
- IF IN EYES:
- Immediately call a POISON CENTER/doctor/…
- Call a POISON CENTER/doctor/… if you feel unwell.
- Get medical advice/attention.
- Rinse mouth.
- If skin irritation occurs:
- Remove contact lenses, if present and easy to do. Continue rinsing.
- Wash with plenty of water/…
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open 1-Naphthol in the GHS label constructor →
07 · Health hazards
1-Naphthol health hazards and exposure limits
1-Naphthol hazard summary
Toxic by ingestion or skin absorption; [Hawley] A skin and respiratory tract irritant; May cause severe damage to eyes; [eChemPortal: ESIS] An irritant; A severe eye irritant which may cause serious injury; May be absorbed through skin; May cause kidney injury; Effects in high-dose animal studies include impaired liver function tests and CNS injury; [MSDSonline] May cause skin irritation and eye injury; [Ullmann] Toxic by ingestion; Alpha isomer is more toxic than beta isomer; Lethal human dose = 50-500 mg/kg (beta-Naphthol); Acute effects include liver and kidney injury, hemolytic anemia, and lens opacities; [HSDB]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
08 · Physical and chemical properties
1-Naphthol 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.
1-Naphthol boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 288 °C (550.4 °F) | HSDB | |
| 282.5 °C (540.5 °F) | at 760 mmHg | DOE PAC | |
| 279.5 °C (535.1 °F) | range, midpoint shown, at 760 mmHg | HMDB |
1-Naphthol melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 96 °C (204.8 °F) | HSDB | |
| 94.5 °C (202.1 °F) | range, midpoint shown, at 760 mmHg | HMDB |
1-Naphthol density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.0954 g/cm³ | at 98.7 °C | HSDB |
| 1.0989 g/cm³ | at 99 °C | DOE PAC |
1-Naphthol solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Very soluble in ethanol and ether, soluble in acetone | HSDB | |
| Freely soluble in benzene, chloroform and alkali hydroxide solutions | HSDB | ||
| In water, 866 mg/L at 25 °C | at 25 °C | HSDB |
1-Naphthol vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 1.7 mmHg | at 110 °C, extrapolated to solid-phase | HSDB |
| 1.7 mmHg | at 100 °C | DOE PAC | |
| 0.000274 mmHg | Haz-Map |
1-Naphthol flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | 153 °C (307.4 °F) | open cup | HSDB |
1-Naphthol autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | 541.7 °C (1007.1 °F) | HSDB |
1-Naphthol odor threshold
| Property | Value | Conditions | Source |
|---|---|---|---|
| Odor threshold | Recognition: 0.0030-0.0052 mg/cu m | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
1-Naphthol fire and explosion behaviour
These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.
1-Naphthol fire potential
Combustible when exposed to heat or flame.
Source: Hazardous Substances Data Bank (HSDB)
10 · Handling and storage
1-Naphthol storage and handling
1-Naphthol storage conditions
Keep in dark places.
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check 1-Naphthol in the storage compatibility matrix →
11 · Questions
1-Naphthol — frequently asked questions
What is the CAS number of 1-Naphthol?
The CAS number of 1-Naphthol is 90-15-3. Its EC number is 201-969-4.
What is the chemical formula of 1-Naphthol?
The molecular formula of 1-Naphthol is C10H8O and its molecular weight is 144.17 g/mol.
What does a 1-Naphthol label have to show?
Under CLP Annex VI the label for 1-Naphthol carries the pictograms Corrosion and Exclamation mark and the signal word is Danger.
Is 1-Naphthol flammable?
CLP Annex VI assigns 1-Naphthol 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. The flash point reported for it is 153 °C (307.4 °F), open cup (HSDB).
Is 1-Naphthol a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for 1-Naphthol. 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 boiling point of 1-Naphthol?
The boiling point reported for 1-Naphthol is 288 °C (550.4 °F) (HSDB).
What is the melting point of 1-Naphthol?
The melting point reported for 1-Naphthol is 96 °C (204.8 °F) (HSDB).
How should 1-Naphthol be stored?
Keep in dark places. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to 1-Naphthol
Keep going: substances starting with 0–9, or search the whole database by name, CAS number, pictogram or signal word.