Chemical Datasheet
HYDROQUINONE |
|
Chemical Identifiers
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| CAS Number | UN/NA Number | DOT Hazard Label | USCG CHRIS Code |
|---|---|---|---|
|
|
||
| NIOSH Pocket Guide | International Chem Safety Card | ||
Hydroquinone
|
|||
NFPA 704
| Diamond | Hazard | Value | Description | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Health
|
2 | Can cause temporary incapacitation or residual injury. | |||||||||
Flammability
|
1 | Must be preheated before ignition can occur. | ||||||||||
Instability
|
0 | Normally stable, even under fire conditions. | ||||||||||
Special
|
(NFPA, 2010)
General Description
Light colored crystals or solutions. May irritate the skin, eyes and mucous membranes. Mildly toxic by ingestion or skin absorption.
Hazards
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The
Hazard fields
include
special hazard alerts
air and water
reactions, fire hazards, health hazards, a reactivity profile, and
details about
reactive groups assignments
and
potentially incompatible absorbents.
The information in CAMEO Chemicals comes from a variety of
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Reactivity Alerts
none
Air & Water Reactions
Darkens on exposure to air and light. Miscible in water. Solutions become brown in air due to oxidation. Oxidation is very rapid in the presence of alkali.
Fire Hazard
Dust cloud may explode if ignited in an enclosed area. It can react with oxidizing materials and is rapidly oxidized in the presence of alkaline materials. Oxidizes in air. (EPA, 1998)
Health Hazard
This material is very toxic; the probable oral lethal dose for humans is 50-500 mg/kg, or between 1 teaspoon and 1 ounce for a 150 lb. person. It is irritating but not corrosive. Fatal human doses have ranged from 5-12 grams, but 300-500 mg have been ingested daily for 3-5 months without ill effects. Death is apparently initiated by respiratory failure or anoxia. (EPA, 1998)
Reactivity Profile
HYDROQUINONE is a slight explosion hazard when exposed to heat. Incompatible with strong oxidizing agents. Also incompatible with bases. It reacts with oxygen and sodium hydroxide. Reacts with ferric salts (NTP, 1992). Hot and/or concentrated NaOH can cause hydroquinone to decompose exothermically at elevated temperature. (NFPA Pub. 491M, 1975, 385)
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents
No information available.
Response Recommendations
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The
Response Recommendation fields
include isolation and evacuation distances, as well as recommendations for
firefighting, non-fire response, protective clothing, and first aid. The
information in CAMEO Chemicals comes from a variety of
data sources.
Isolation and Evacuation
Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:
IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.
SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.
FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.
SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.
FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
Firefighting
Wear self-contained (positive pressure if available) breathing apparatus and full protective clothing.
For small fires use dry chemical, carbon dioxide, water spray or foam. Move container from fire area if you can do so without risk. This compound is a slight fire or explosion hazard. (EPA, 1998)
For small fires use dry chemical, carbon dioxide, water spray or foam. Move container from fire area if you can do so without risk. This compound is a slight fire or explosion hazard. (EPA, 1998)
Non-Fire Response
Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:
Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent dust cloud. For Asbestos, avoid inhalation of dust. Cover spill with plastic sheet or tarp to minimize spreading. Do not clean up or dispose of, except under supervision of a specialist.
SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area.
SMALL SPILL: Pick up with sand or other non-combustible absorbent material and place into containers for later disposal.
LARGE SPILL: Dike far ahead of liquid spill for later disposal. Cover powder spill with plastic sheet or tarp to minimize spreading. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2024)
Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent dust cloud. For Asbestos, avoid inhalation of dust. Cover spill with plastic sheet or tarp to minimize spreading. Do not clean up or dispose of, except under supervision of a specialist.
SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area.
SMALL SPILL: Pick up with sand or other non-combustible absorbent material and place into containers for later disposal.
LARGE SPILL: Dike far ahead of liquid spill for later disposal. Cover powder spill with plastic sheet or tarp to minimize spreading. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2024)
Protective Clothing
Excerpt from NIOSH Pocket Guide for Hydroquinone:
Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.
Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.
Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.
Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.
Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.
Provide: EYEWASH (>7%) - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection. (>7%) (NIOSH, 2024)
:Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact.
Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact.
Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated.
Remove: WHEN WET OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced.
Change: DAILY - Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premises.
Provide: EYEWASH (>7%) - Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substances; this is irrespective of the recommendation involving the wearing of eye protection. (>7%) (NIOSH, 2024)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Signs and Symptoms of Acute Hydroquinone Exposure: Signs and symptoms of acute exposure to hydroquinone may be severe and include dyspnea (shortness of breath), a sense of suffocation, increased respiratory rate, and respiratory failure. Pallor (paleness of the skin), cyanosis (blue tint to skin and mucous membranes), and cardiovascular collapse may occur. Neurologic effects include headache, tinnitus (ringing in the ears), dizziness, delirium, muscle twitching, tremor, and convulsions. Nausea, vomiting, and the production of green to brown-green urine may also occur. Hydroquinone may be irritating and corrosive to the skin, eyes, and mucous membranes. Jaundice (yellow tint to skin) may be noticed.
Emergency Life-Support Procedures: Acute exposure to hydroquinone may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.
Inhalation Exposure:
1. Move victims to fresh air. Emergency personnel should avoid self-exposure to hydroquinone.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Transport to a health care facility.
Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self- exposure to hydroquinone.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Remove contaminated clothing as soon as possible.
4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
5. Wash exposed skin areas twice with soap and water.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Transport to a health care facility.
Ingestion Exposure:
1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen.
2. IMMEDIATELY give the victims water or milk: children up to 1 year old, 125 mL (4 oz or 1/2 cup); children 1 to 12 years old, 200 mL (6 oz or 3/4 cup); adults, 250 mL (8 oz or 1 cup). Water or milk should be given only if victims are conscious and alert.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Vomiting may be induced with syrup of Ipecac. If elapsed time since ingestion of hydroquinone is unknown or suspected to be greater than 30 minutes, do not induce vomiting and proceed to Step
5.Ipecac should not be administered to children under 6 months of age.Warning: Ingestion of hydroquinone may result in sudden onset of seizures or loss of consciousness. Syrup of Ipecac should be administered only if victims are alert, have an active gag-reflex, and show no signs of impending seizure or coma. If ANY uncertainty exists, proceed to Step
5.The following dosages of Ipecac are recommended: children up to 1 year old, 10 mL (1/3 oz); children 1 to 12 years old, 15 mL (1/2 oz); adults, 30 mL (1 oz). Ambulate (walk) the victims and give large quantities of water. If vomiting has not occurred after 15 minutes, Ipecac may be readministered. Continue to ambulate and give water to the victims. If vomiting has not occurred within 15 minutes after second administration of Ipecac, administer activated charcoal.
5. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.
6. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults.
7. Transport to a health care facility. (EPA, 1998)
Emergency Life-Support Procedures: Acute exposure to hydroquinone may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.
Inhalation Exposure:
1. Move victims to fresh air. Emergency personnel should avoid self-exposure to hydroquinone.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Transport to a health care facility.
Dermal/Eye Exposure:
1. Remove victims from exposure. Emergency personnel should avoid self- exposure to hydroquinone.
2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.
3. Remove contaminated clothing as soon as possible.
4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.
5. Wash exposed skin areas twice with soap and water.
6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
7. Transport to a health care facility.
Ingestion Exposure:
1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen.
2. IMMEDIATELY give the victims water or milk: children up to 1 year old, 125 mL (4 oz or 1/2 cup); children 1 to 12 years old, 200 mL (6 oz or 3/4 cup); adults, 250 mL (8 oz or 1 cup). Water or milk should be given only if victims are conscious and alert.
3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.
4. Vomiting may be induced with syrup of Ipecac. If elapsed time since ingestion of hydroquinone is unknown or suspected to be greater than 30 minutes, do not induce vomiting and proceed to Step
5.Ipecac should not be administered to children under 6 months of age.Warning: Ingestion of hydroquinone may result in sudden onset of seizures or loss of consciousness. Syrup of Ipecac should be administered only if victims are alert, have an active gag-reflex, and show no signs of impending seizure or coma. If ANY uncertainty exists, proceed to Step
5.The following dosages of Ipecac are recommended: children up to 1 year old, 10 mL (1/3 oz); children 1 to 12 years old, 15 mL (1/2 oz); adults, 30 mL (1 oz). Ambulate (walk) the victims and give large quantities of water. If vomiting has not occurred after 15 minutes, Ipecac may be readministered. Continue to ambulate and give water to the victims. If vomiting has not occurred within 15 minutes after second administration of Ipecac, administer activated charcoal.
5. Activated charcoal may be administered if victims are conscious and alert. Use 15 to 30 g (1/2 to 1 oz) for children, 50 to 100 g (1-3/4 to 3-1/2 oz) for adults, with 125 to 250 mL (1/2 to 1 cup) of water.
6. Promote excretion by administering a saline cathartic or sorbitol to conscious and alert victims. Children require 15 to 30 g (1/2 to 1 oz) of cathartic; 50 to 100 g (1-3/4 to 3-1/2 oz) is recommended for adults.
7. Transport to a health care facility. (EPA, 1998)
Physical Properties
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The
Physical Property fields
include properties such as vapor pressure and
boiling point, as well as explosive limits and
toxic exposure thresholds
The information in CAMEO Chemicals comes from a variety of
data sources.
Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
| Chemical Formula: |
|
Flash Point:
329°F
(EPA, 1998)
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature:
960°F
(USCG, 1999)
Melting Point:
338 to 340°F
(EPA, 1998)
Vapor Pressure:
4 mmHg
at 302°F
(EPA, 1998)
Vapor Density (Relative to Air):
3.81
(EPA, 1998)
- Heavier than air; will sink
Specific Gravity:
1.332
at 59°F
(EPA, 1998)
- Denser than water; will sink
Boiling Point:
545 to 549°F
at 760 mmHg
(EPA, 1998)
Molecular Weight:
110.11
(EPA, 1998)
Water Solubility:
10 to 50 mg/mL
at 68°F
(NTP, 1992)
Ionization Energy/Potential:
7.95 eV
(NIOSH, 2024)
IDLH:
50 mg/m3
(NIOSH, 2024)
AEGLs (Acute Exposure Guideline Levels)
No AEGL information available.ERPGs (Emergency Response Planning Guidelines)
No ERPG information available.PACs (Protective Action Criteria)
| Chemical | PAC-1 | PAC-2 | PAC-3 |
|---|---|---|---|
| Hydroquinone (123-31-9) | 3 mg/m3 | 20 mg/m3 | 120 mg/m3 |
(DOE, 2024)
Regulatory Information
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The
Regulatory Information fields
include information from
the U.S. Environmental Protection Agency's Title III Consolidated List of
Lists,
the U.S. Cybersecurity and Infrastructure Security Agency's Chemical Facility
Anti-Terrorism Standards,
and the U.S. Occupational Safety and Health Administration's
Process Safety Management of Highly Hazardous Chemicals Standard List
(see more about these
data sources).
EPA Consolidated List of Lists
| Regulatory Name | CAS Number/ 313 Category Code |
EPCRA 302 EHS TPQ |
EPCRA 304 EHS RQ |
CERCLA RQ | EPCRA 313 TRI |
RCRA Code |
CAA 112(r) RMP TQ |
|---|---|---|---|---|---|---|---|
| Hydroquinone | 123-31-9 | 500/10000 pounds | 100 pounds | 100 pounds | 313 |
(EPA List of Lists, 2024)
CISA Chemical Facility Anti-Terrorism Standards (CFATS)
No regulatory information available.OSHA Process Safety Management (PSM) Standard List
No regulatory information available.Alternate Chemical Names
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This section provides a listing of alternate names for this chemical,
including trade names and synonyms.
- AIDA
- ALPHA-HYDROQUINONE
- ARCTUVIN
- BENZENE, P-DIHYDROXY-
- 1,4-BENZENEDIOL
- BENZOHYDROQUINONE
- BENZOQUINOL
- 1,4-BENZOQUINOL
- BETA-QUINOL
- BLACK AND WHITE BLEACHING CREAM
- BQ(H)
- DIAK 5
- DIHYDROQUINONE
- DIHYDROXYBENZENE
- 1,4-DIHYDROXYBENZENE
- ELDOPAQUE
- ELDOQUIN
- HE 5
- HYDROQUINOL
- HYDROQUINOLE
- HYDROQUINONE
- 4-HYDROXYPHENOL
- NCI-C55834
- P-BENZENEDIOL
- P-DIHYDROQUINONE
- P-DIHYDROXYBENZENE
- P-DIOXOBENZENE
- P-DIOXYBENZENE
- P-HYDROQUINONE
- P-HYDROXYPHENOL
- P-PHENYLENEDIOL
- P-QUINOL
- PARA-DIHYDROXYBENZENE
- PARA-DIOXYBENZENE
- PARA-HYDROQUINONE
- PHIAQUIN
- PYROGENTISIC ACID
- QUINNONE
- QUINOL
- TECQUINOL
- TENOX HQ
- TEQUINOL
- USAF EK-356
Web site owner:
Office of Response and Restoration,
National Ocean Service,
National Oceanic and Atmospheric Administration.
USA.gov.
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