2,4-Dinitrophenol

H300: Fatal if swallowed [Danger Acute toxicity, oral]

H311: Toxic in contact with skin [Danger Acute toxicity, dermal]

H331: Toxic if inhaled [Danger Acute toxicity, inhalation]

H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

H400: Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

P260, P261, P262, P264, P270, P271, P273, P280, P301+P316, P302+P352, P304+P340, P316, P319, P321, P330, P361+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

H201 (40.8%): (Deleted) Explosive; mass explosion hazard [Danger Explosives]

H300 (53.1%): Fatal if swallowed [Danger Acute toxicity, oral]

H301 (46.9%): Toxic if swallowed [Danger Acute toxicity, oral]

H311 (98%): Toxic in contact with skin [Danger Acute toxicity, dermal]

H331 (95.9%): Toxic if inhaled [Danger Acute toxicity, inhalation]

H372 (38.8%): Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

H373 (61.2%): May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]

H400 (100%): Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

P210, P230, P240, P250, P260, P261, P262, P264, P270, P271, P273, P280, P301+P316, P302+P352, P304+P340, P316, P319, P321, P330, P361+P364, P370+P380, P372, P373, P391, P401, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 49 reports by companies from 12 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

P262, P264, P270, P280, P301+P316, P302+P352, P316, P321, P330, P361+P364, P405, and P501 (click each P-code to see the statement)

H410: Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

P273, P391, and P501 (click each P-code to see the statement)

H201: (Deleted) Explosive; mass explosion hazard [Danger Explosives]

H310: Fatal in contact with skin [Danger Acute toxicity, dermal]

H315: Causes skin irritation [Warning Skin corrosion/irritation]

H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]

H361: Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]

H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]

H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]

P203, P210, P230, P240, P250, P260, P262, P264, P270, P280, P301+P316, P302+P352, P308+P316, P316, P318, P319, P321, P330, P332+P317, P361+P364, P362+P364, P370+P380, P372, P373, P401, P405, and P501 (click each P-code to see the statement)

Fresh air, rest.

Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer immediately for medical attention .

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rest. Refer immediately for medical attention.

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: DO NOT INDUCE VOMITING. Phenols are very toxic poisons AND corrosive and irritating, so that inducing vomiting may make medical problems worse. IMMEDIATELY call a hospital or poison control center and locate activated charcoal, egg whites, or milk in case the medical advisor recommends administering one of them. If advice from a physician is not readily available and the victim is conscious and not convulsing, give the victim a glass of activated charcoal slurry in water or, if this is not available, a glass of milk, or beaten egg whites and IMMEDIATELY transport victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, assure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· For corrosives, in case of contact, immediately flush skin or eyes with running water for at least 30 minutes. Additional flushing may be required.

· Removal of solidified molten material from skin requires medical assistance.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

Excerpt from ERG Guide 113 [Flammable Materials (Wet / Desensitized Explosive)]:

CARGO FIRE: DO NOT fight fire when fire reaches cargo! Cargo may EXPLODE! Stop all traffic and clear the area for at least 1600 meters (1 mile) in all directions and let burn. Do not move cargo or vehicle if cargo has been exposed to heat.

TIRE OR VEHICLE FIRE: Use plenty of water - FLOOD it! If water is not available, use CO2, dry chemical or dirt. If possible, and WITHOUT RISK, use unmanned master stream devices or monitor nozzles from maximum distance to prevent fire from spreading to cargo area. Pay special attention to tire fires as re-ignition may occur. Stand by, at a safe distance, with extinguisher ready for possible re-ignition. (ERG, 2024)

Use water in large amounts. In case of fire: keep drums, etc., cool by spraying with water. Combat fire from a sheltered position.

If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use foam, dry chemical, or carbon dioxide. /Dinitrophenol solutions/

If material on fire or involved in fire: Dangerously explosive. Do not fight fires in a cargo of explosives. Evacuate area and let burn. /Dinitrophenol, dry or wetted with less than 15% water by weight)

If material on fire or involved in fire: Dangerously explosive. Flood with water. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. /Dinitrophenol, wetted with at least 15% water/

Wear positive pressure self-contained breathing apparatus when fighting fires involving this material.

The primary hazard is from blast effect where the entire load can explode instantaneously and not from flying projectiles and fragments. /Dinitrophenol, dry/

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Ventilate closed spaces before entering, but only if properly trained and equipped.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· Do not touch damaged containers or spilled material unless wearing appropriate protective clothing.

· Stop leak if you can do it without risk.

· Prevent entry into waterways, sewers, basements or confined areas.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· DO NOT GET WATER INSIDE CONTAINERS.

· All equipment used when handling the product must be grounded.

· Do not touch or walk through spilled material.

Small Spill

· Flush area with large amounts of water.

Large Spill

· Wet down with water and dike for later disposal.

· KEEP "WETTED" PRODUCT WET BY SLOWLY ADDING FLOODING QUANTITIES OF WATER.

Excerpt from ERG Guide 113 [Flammable Materials (Wet / Desensitized Explosive)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area immediately for at least 100 meters (330 feet) in all directions.

LARGE SPILL: Consider initial evacuation for 500 meters (1/3 mile) in all directions.

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.

· For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.

· For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind direction, as necessary.

· 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.

· Isolate spill or leak area immediately for at least 100 meters (330 feet) in all directions.

· Consider initial evacuation for 500 meters (1/3 mile) in all directions.

Evacuate danger area! Consult an expert! Personal protection: complete protective clothing including self-contained breathing apparatus. Do not allow to dry out. Do NOT let this chemical enter the environment. Sweep spilled substance into containers. Carefully collect remainder. Store and dispose of according to local regulations.

Evacuate persons not wearing protective equipment from area of spill or leak until clean-up is complete. Remove all ignition sources. Wet spilled material with water. Collect powdered material in the most convenient and safe manner and deposit in sealed containers. Ventilate area after clean-up is complete. It may be necessary to contain and dispose of this chemical as a hazardous waste. Keep dinitrophenol out of a confined space, such as a sewer, because of the possibility of an explosion, unless the sewer is designed to prevent the build-up of explosive concentrations. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Contact your Department of Environmental Protection of your regional office of the federal EPA for specific recommendations.

Environmental considerations: Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be contained with a flexible impermeable membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder. /Dinitrophenol solutions/

Environmental considerations: Water spill: use natural barriers or oil spill control booms to limit spill travel. use surface active agent (e.g., detergent, soaps, alcohols), if approved by EPA. Inject "universal" gelling agent to solidify encircled spill and increase effectiveness of booms. If dissolved in region of 10 ppm or greater concentration, apply activated carbon at ten times the spilled amount. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates. /Dinitrophenol solutions/

Environmental considerations - land spill: dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Cover solids with a plastic sheet to prevent dissolving in rain or fire fighting water. /Dinitrophenol, wetted with at least 15% water/

Environmental considerations - water spill: Use natural deep water pockets, excavated lagoons, or sand bag barriers to trap material at bottom. If dissolved in region of 10 ppm or greater concentration, apply activated carbon at ten times the spilled amount. Remove trapped material with suction hoses. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates. /Dinitrophenol, wetted with at least 15% water/

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number P048, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Dinitrophenol: Incinerate (1800 °F, 2.0 sec minimum) with adequate scrubbing equipment for the removal of NOx. Dinitrophenol ... /is a/ waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration. /Dinitrophenol/

A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.

Chemical Treatability of 2,4-Dinitrophenol; Concentration Process: Biological Treatment. Chemical Classification: Phenol; Scale of Study: Respirometer Study; Type of Wastewater Used: Synthetic Wastewater; Results of Study: Max oxygen uptake was 27.7 ppm of aeration.

For more Disposal Methods (Complete) data for 2,4-Dinitrophenol (8 total), please visit the HSDB record page.

If material not on fire and not involved in fire: Keep sparks, flames, and other sources of ignition away. Keep material wet. Wet spilled material before picking it up. Do not attempt to sweep up dry material. /Dinitrophenol, dry or wetted with less than 15% water by weight/

Excerpt from ERG Guide 113 [Flammable Materials (Wet / Desensitized Explosive)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material.

SMALL SPILL: Flush area with large amounts of water.

LARGE SPILL: Wet down with water and dike for later disposal. KEEP "WETTED" PRODUCT WET BY SLOWLY ADDING FLOODING QUANTITIES OF WATER. (ERG, 2024)

Fireproof. Store in an area without drain or sewer access. Provision to contain effluent from fire extinguishing. Cool. Separated from combustible substances, reducing agents and food and feedstuffs.

/Dinitrophenol/ ... should be stored in a cool ventilated place away from area of acute fire hazard and away from powerful oxidizing agents. /Dinitrophenol/

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE.

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

0.13 [mg/m3]

1.4 [mg/m3]

8.3 [mg/m3]

Acute Oral: 0.01 mg/kg/day (L168)

Small Fire

· Dry chemical, CO2 or water spray.

Large Fire

· Dry chemical, CO2, alcohol-resistant foam or water spray.

· If it can be done safely, move undamaged containers away from the area around the fire.

· Dike runoff from fire control for later disposal.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Do not get water inside containers.

· Cool containers with flooding quantities of water until well after fire is out.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

CARGO Fire

· DO NOT fight fire when fire reaches cargo! Cargo may EXPLODE!

· Stop all traffic and clear the area for at least 1600 meters (1 mile) in all directions and let burn.

· Do not move cargo or vehicle if cargo has been exposed to heat.

TIRE or VEHICLE Fire

· Use plenty of water - FLOOD it! If water is not available, use CO2, dry chemical or dirt.

· If possible, and WITHOUT RISK, use unmanned master stream devices or monitor nozzles from maximum distance to prevent fire from spreading to cargo area.

· Pay special attention to tire fires as re-ignition may occur. Stand by, at a safe distance, with extinguisher ready for possible re-ignition.

A nuisance-causing concentration of airborne particles can be reached quickly when dispersed.

The substance may be irritating to the eyes and skin.

Repeated or prolonged contact with skin may cause dermatitis. The substance may have effects on the metabolism. This may result in cataract, cardiovascular disorders and nervous system impairment.

Wear goggles, self-contained breathing apparatus, and rubber overclothing (including gloves). (USCG, 1999)

Wear appropriate chemical protective clothing. /Dinitrophenol solutions/

Wear appropriate chemical protective gloves, boots, and goggles. /Dinitrophenol, wetted with at least 15% water/

Respirator Selection: Where there is potential for exposure to dinitrophenol, use a NIOSH/MSHA approved supplied-air respirator with a full facepiece operated in the positive pressure mode, or with a full facepiece, hood, or helmet in the continuous flow mode; or use a NIOSH/MSHA approved self-contained breathing apparatus with a full facepiece operated in pressure-demand or other positive pressure mode.

People exposed to the solid or to a strong soln should wear protective clothing, hand protection and, in confined spaces, the use of respiratory protective equipment. /Dinitrophenol/

NO open flames, NO sparks and NO smoking. Do NOT expose to friction or shock. Use non-sparking handtools. Prevent deposition of dust. Closed system, dust explosion-proof electrical equipment and lighting.

PREVENT DISPERSION OF DUST! STRICT HYGIENE!

Use local exhaust or breathing protection.

Protective gloves. Protective clothing.

Wear safety goggles.

2,4-dinitrophenol appears as solid yellow crystals. Explosive when dry or with less than 15% water. The primary hazard is from blast of an instantaneous explosion and not flying projectiles and fragments. slightly soluble in water and soluble in ether and solutions of sodium or potassium hydroxide.

Yellow crystals with a sweet, musty odor; [CHRIS]

CRYSTALS WITH CHARACTERISTIC ODOUR.

Pale yellow platelets or leaflets from water

Yellowish to yellow orthorhombic crystals

SWEET, MUSTY ODOR

BITTER TASTE

Sublimes (when carefully heated) (NTP, 1992)

Sublimes

234 to 237 °F (NTP, 1992)

114.8 °C

less than 1 mg/mL at 67.1 °F (NTP, 1992)

Soluble in ethanol, ethyl ether, benzene, methanol

Solubility at 15 °C (g/100 g solution): ethyl acetate 15.55; acetone 35.90; chloroform 5.39; pyridine 20.08; carbon tetrachloride 0.423; toluene 6.36

Soluble in aqueous alkaline solutions

In water, 5,600 mg/L at 18 °C; 43,000 mg/L at 100 °C

In water, 2,790 mg/L at 20 °C

Solubility in water, g/l: 6 (poor)

>27.6 [ug/mL] (The mean of the results at pH 7.4)

1.68 at 68 °F (USCG, 1999) - Denser than water; will sink

1.683 g/cu cm at 24 °C

Relative density (water = 1): 1.68

1.683 @ 24°C

6.35 (NTP, 1992) - Heavier than air; will sink (Relative to Air)

6.35 (Air = 1)

Relative vapor density (air = 1): 6.36

0.00039 [mmHg]

3.9X10-4 mm Hg at 20 °C

log Kow = 1.67

1.67 (estimated)

Henry's Law constant = 8.6X10-8 atm-cu m/mole at 25 °C

Appear to be stable in acid solution, but are susceptible to decomposition by UV radiation in alkaline solutions. /Dintrophenols/

When heated to decomposition it emits toxic fumes of /nitroxides/.

May explosively decompose on shock, friction, or concussion.

648.0 KG CAL/G MOL WT @ 20 °C

pH range: 2.6 Colorless, 4.4 Yellow

Negative

Agilent XCT

Electrospray ionization

ammonia (10nM)

Highly flammable. Slightly soluble in water.

Nitro, Nitroso, Nitrate, and Nitrite Compounds, Organic

Phenols and Cresols

Highly Flammable

Explosive

Strong Oxidizing Agent

2,4-DINITROPHENOL may explode if subjected to heat or flame. May explode if allowed to dry out. Forms explosive salts with alkalis and ammonia. Incompatible with heavy metals and their compounds. Also incompatible with strong oxidizing agents, strong bases and reducing agents. Reacts with combustibles. (NTP, 1992)

Contact with reducing agents, combustibles may cause fire and explosions. Forms shock-sensitive explosive salts with ammonia, strong bases, and most metals. May accumulate static electrical charges /which/ may cause ignition of its vapors.

Dinitrophenol forms explosive salts with alkali or ammonia and should not be heated with them in closed vessels ...

Acute 2,4-dinitrophenol poisoning (from ingestion) involves uncoupling of oxidative phosphorylation, which presumably reduces body's reservoirs of high-energy phosphate. This stimulates oxidative metabolism and, in turn, the heat production of the body. Oxygen consumption, body temperature, respiration and heart rate are all increased. 2,4-Dinitrophenol has been suggested to bind serum proteins such as transthyretin. In fact it was proposed as a therapeutic agent for the prevention/inhibition of amyloid diseases through stabilization of the native fold of transthyretin. (T21, A126, A127)

2,4-Dinitrophenol

2 x 10 ^-3 mg/kg-day

Semi-Volatile Organic Compound (SVOC)

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

No indication of carcinogenicity to humans (not listed by IARC).

2,4-DNP can cause cataracts following ingestion of a small dose for short or long periods. This condition could lead to blindness in both eyes. Breathing in, swallowing, or having skin contact with large amounts of DNP can lead to death.(L168)

The substance can be absorbed into the body through the skin and by ingestion.

Oral (L170); inhalation (L170) ; dermal (L170)

See Ingestion.

MAY BE ABSORBED! Redness. Roughness. Yellow staining of the skin. Further see Inhalation.

Yellow vision. Redness. Conjunctivitis.

Nausea. Sweating. Severe thirst. Fever. Increased heart rate. Vomiting. Shock or collapse.

Dermal contact may results in redness, roughness, yellow staining of the skin. Nausea, vomiting, palpitations, collapse, sweating occur after inhalation or ingestion. (L170)

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

Nephrotoxin - The chemical is potentially toxic to the kidneys in the occupational setting.

Methemoglobinemia - The presence of increased methemoglobin in the blood; the compound is classified as secondary toxic effect

Other Poison - Uncoupler

Dermatotoxin - Skin burns.

2 x 10^-2 mg/kg-day

PDF Document

Inadequate information to assess carcinogenic potential

ATSDR Final

IRIS Current

PPRTV Current

LCLo (dog) = 300 mg/m3/30 min

LD50: 14-43 mg/kg (Oral, Human) (T30)

Lethal doses for orally ingested 2,4-dinitrophenol in humans have been reported to be 14 to 43 mg/kg ... .

Fatal dose in adults is about 1 to 3 g by mouth; 3 g has also proved fatal in divided doses over a period of 5 days. /Dinitrophenol/

LD50 Rat oral 30 mg/kg

LD50 Rat male weanling oral 71 mg/kg

LD50 Rat ip 28.5 to 35 mg/kg /From table/

LD50 Rat ip 20 mg/kg

For more Non-Human Toxicity Values (Complete) data for 2,4-Dinitrophenol (12 total), please visit the HSDB record page.

There is no specific antidote for 2,4-DNP poisoning. Symptomatic treatment includes replacing oxygen and fluids, controlling temperature by administering sponge baths and ice packs, and using a fan to promote air flow and evaporation. In fully conscious patients, administer cold, sugar-containing liquids by mouth as tolerated. In cases of skin contact, bathe and shampoo contaminated skin and hair promptly. (L179)

2,4-DNP appears to markedly increase the rate of ethanol metabolism in rat liver slices by 100-160% and in rats in vivo by 20-30%. Because 2,4-DNP uncouples mitochondrial electron transport from oxidative phosphorylation, the oxidation of NADH to NAD+ is accelerated in the mitochondria. Reoxidation of NADH rather than the activity of alcohol dehydrogenase is the rate-limiting step in the metabolism of ethanol, and, therefore, the metabolic effect of 2,4-DNP enhances the clearance of ethanol. Because 2,4-DNP is known to augment the rate of respiration and perspiration, .2.7-8.2% of the initial dose of ethanol was also eliminated by expiration and cutaneous evaporation in the rat.

In isolated perfused rat livers, 2,4-DNP caused a depletion of the mitochondrial calcium pool, without altering the extramitochondrial calcium pool. Because 2,4-DNP uncouples oxidative phosphorylation from electron transport by dissipating the electrochemical potential, which provides the energy for the accumulation of calcium in the mitochondrial matrix, only the calcium pool in the mitochondria was affected. 2,4-DNP also caused a rapid increase in NAD, along with a decrease in NADH, a rapid decrease in protein thiol content, but only a slow decrease in nonprotein thiol (e.g., reduced glutathione [GSH]), and an increase in cytoplasmic calcium concentration in isolated rat intestinal cells. This DNP-induced protein thiol loss and/or increase of cytoplasmic calcium concentration induced cell rounding and decreased cell viability. Incubation of salicylate and 2,4-DNP with intestinal cells caused a reduction in the 2,4-DNP-induced increase in cytosolic free calcium concentration by complexation, which facilitated the release of calcium from cells. Salicylate also inhibited DNP-induced cell rounding and increased cell viability in the small intestine.

Salicylate (aspirin), which also uncouples oxidative phosphorylation in mitochondrial preparations (although at much higher concentrations than 2,4-DNP), partially inhibited a protein thiol loss induced by 2,4-DNP, but not nonprotein thiol loss by 2,4-DNP in the small intestine of rats. Although DNP inhibits the absorption of the hydrophilic drug, cefmetazole, incubation of DNP and salicylate removed this inhibitory effect in the small intestine. By preventing the DNP-induced protein thiol loss in the small intestine, salicylate appears to enhance diffusivity of cefmetazole in the small intestines. However, salicylate at very high doses can also increase respiratory rates and produce hyperthermia in humans, and possibly exaggerate these signs in persons acutely exposed to 2,4-DNP.

Pretreatment of rats with haloperidol significantly diminished the hyperpyrexia and lethality of 2,4-DNP by interfering with the uncoupling of oxidative phosphorylation by 2,4-DNP. The protection by haloperidol may have occurred by an indirect action on the mitochondrial membrane.

For more Interactions (Complete) data for 2,4-Dinitrophenol (15 total), please visit the HSDB record page.

LC50; Species: Lepomis macrochirus (bluegill); Concentration: 620 ug/L for 96 hr /Conditions of bioassay not specified in source examined/

LC50; Species: Salmo salar (Atlantic salmon); Concentration: 700 ug/L for 96 hr /Conditions of bioassay not specified in source examined/

LC50; Species: Mysidopsis bahia (Mysid shrimp); Concentration: 4850 ug/L for 96 hr /Conditions of bioassay not specified in source examined/

LC50; Species: Herring embryo; Concentration: 5,500 ug/L for 96 hr /Conditions of bioassay not specified in source examined/

For more Ecotoxicity Values (Complete) data for 2,4-Dinitrophenol (50 total), please visit the HSDB record page.

/BIRDS and MAMMALS/ In a study where bobwhite quail were exposed to 2,4-DNP in the diet, 1 of 6 hens in a group consuming 56.1 mg/kg/day died on the eighth and final day of exposure. Necropsy revealed a marked scarcity of subcutaneous fat, reduced visceral fat, and possibly some shrinkage of leg and breast muscles.

/BIRDS and MAMMALS/ Bobwhite quail were exposed to 2,4-dinitrophenol (DNP) in a respirometer designed to continuously monitor exchange of O2 and CO2, from which metabolic rates (MR) were estimated. After 14-16 days of acclimation to the system (temperature 22 °C, light cycle 8L:14D), hens received feed amended with 0, 625 ppm, or 1250 ppm DNP ad libitum for eight days, followed by 2-5 days of 0 ppm feed. The 625 ppm treatment produced dark period MR 31-41% higher than corresponding control values, and light period MR 23-32% higher than controls. The 1250 ppm treatment produced dark period MR 48-77% higher than control values, and light period MR 41-67% higher than control. Over the eight days of testing, the 625 ppm treatment hens expended 32% more energy than the control hens and hens consuming 1250 ppm feed expended 60% more energy than control hens and lost most of their body fat. In general, the risk of being unable to meet energy demands for survival or reproduction would probably be substantially increased by the observed elevation in MR.

/BIRDS and MAMMALS/ Ducklings fed 2,4-dinitrophenol at a concentration of 2,500 ppm developed cataracts within 24 hr ... Chickens were also susceptible. Cataract was observed in duckling only 3.5 hr after crop intubation. With no further dosing, the lesion cleared within 3 days.

/BIRDS and MAMMALS/ The effects of pharmacologically elevated metabolism on respiratory adjustments were studied in chickens. Adult female white leghorn chickens were decerebrated and allowed to recover from anesthesia. In experiment 1, birds were injected with 2.5 mg/kg 2,4-dinitrophenol. Respiratory and cardiovascular measurements were monitored continuously. After steady state conditions were reestablished, another 2.5 mg/kg 2,4-dinitrophenol injection was given and measurements were taken again. Injections and measurements continued until no further oxygen consumption increase occurred. Some birds received a single 5 mg/kg 2,4-dinitrophenol injection. Measurements were repeated every 5 minutes. In experiment 2, birds had control measurements and arterial blood samples taken at approximately 20 °C. Birds were cooled to 2 °C. After a steady respiratory response was established, measurements were taken. Successive 2,4-dinitrophenol doses caused a progressive oxygen consumption increase in the decerebrated chickens; a 7.5 to 10 mg/kg dose of 2,4-dinitrophenol elicited the maximal oxygen consumption response, approximately 275% of control values. A single 5 mg/kg 2,4-dinitrophenol injection increased oxygen consumption and the respiratory exchange ratio and increased minute ventilation. Ventilation significantly increased within 10 seconds of the start of 2,4-dinitrophenol injection. A steady state was reached approximately 10 minutes after the start of injection. Birds hyperventilated about 45 minutes after injection when the temperature reached approximately 42.3 °C. The respiratory and cardiovascular effects of the increased metabolism during cold exposure was similar to the initial elevated metabolism responses elicited by 2,4-dinitrophenol. Oxygen consumption increased to approximately 185% of control values; V1 increased in a way that oxygen extraction remained unchanged. /It was concluded/ that 2,4-dinitrophenol induced hyper metabolism in the decerebrated chicken is an acceptable model to study respiratory control and gas exchange during exercise in birds.

For more Ecotoxicity Excerpts (Complete) data for 2,4-Dinitrophenol (19 total), please visit the HSDB record page.

1.30e+02

1.60e+03

3.90e+01

5.00e+00

4.40e-02

2.00e-03

Volatile

3.80e+02

4.90e+03

1.20e+02

The substance is very toxic to aquatic organisms. It is strongly advised not to let the chemical enter into the environment.

2,4-Dinitrophenol's production and use in the manufacture of dyes and diaminophenol or its use as an indicator may result in its release to the environment through various waste streams; its former use as a pesticide resulted in its direct release to the environment. If released to air, a vapor pressure of 3.9X10-4 mm Hg at 20 °C indicates 2,4-dinitrophenol will exist solely as a vapor in the atmosphere. Vapor-phase 2,4-dinitrophenol will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 24 days. 2,4-Dinitrophenol may react with nitrate radicals in the atmosphere. 2,4-Dinitrophenol does absorb light at wavelengths >290 nm and therefore may be susceptible to direct photolysis by sunlight. If released to soil, 2,4-dinitrophenol is expected to have very high mobility based upon measured Koc values of 13.5 and 16.6. The pKa of 2,4-dinitrophenol is 4.09, indicating that this compound will exist almost entirely in anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts, as is evident by the measured Koc values. Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Utilizing the Japanese MITI test, 0% of the theoretical BOD was reached in 4 weeks indicating that biodegradation is not an important environmental fate process. However, the biodegradation half-life of 2,4-dinitrophenol in an acidic soil was reported as 32.1 days and the biodegradation half-life in a basic soil was reported as 4.6 days. If released into water, 2,4-dinitrophenol is not expected to adsorb to suspended solids and sediment based upon the measured Koc values. The biodegradation half-life of 2,4-dinitrophenol was reported as 68 days and 2.8 days in aerobic and anaerobic waters, respectively. Volatilization from water surfaces is not expected to be an important fate process based upon its anionic state. BCFs of <0.4-0.7 and <3.7 were measured in carp (Cyprinus carpio) suggesting bioconcentration in aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process since 2,4-dinitrophenol lacks functional groups that hydrolyze under environmental conditions. Occupational exposure to 2,4-dinitrophenol may occur through inhalation and dermal contact with this compound at workplaces where 2,4-dinitrophenol is produced or used. Monitoring data indicate that the general population may be exposed to 2,4-dinitrophenol via inhalation of ambient air, ingestion of drinking water, and dermal contact with products containing 2,4-dinitrophenol. (SRC)

2,4-Dinitrophenol's production and use in the manufacture of dyes and diaminophenol or its use as an indicator(1) may result in its release to the environment through various waste streams(SRC). Its former use as a pesticide(2) resulted in its direct release to the environment(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), a Koc values of 13.5(2) and 16.6(3), indicate that 2,4-dinitrophenol is expected to have very high mobility in soil(SRC). The pKa of 2,4-dinitrophenol is 4.09(4), indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(5). This can be seen in the measured Koc values(SRC). 2,4-Dinitrophenol is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.9X10-4 mm Hg at 20 °C(6). A 0% of theoretical BOD using activated sludge in the Japanese MITI test(7) suggests that biodegradation is not an important environmental fate process in soil(SRC). However, the biodegradation half-life of 2,4-dinitrophenol in an acidic soil was reported as 32.1 days and the biodegradation half-life in a basic soil was reported as 4.6 days(8).

TERRESTRIAL FATE: 2,4-Dinitrophenol is a moderately weak acid that is expected to be highly labile (leachable and plant available) in high-pH soils. The adsorption and degradation behavior of 2,4-dinitrophenol in two sludge-amended, calcareous soils was determined and used to explain 2,4-dinitrophenol uptake by plants grown in the soils in the greenhouse. The 2,4-dinitrophenol adsorption was minor in both soils and was only slightly affected by sludge. The 2,4-dinitrophenol degradation was rapid in both soils and was unaffected by sludge. Thus, despite limited soil adsorption, plant uptake of 2,4-dinitrophenol was minor in all crops and plant parts owing to rapid soil 2,4-dinitrophenol degradation. Even if a municipal sludge highly contaminated with 2,4-dinitrophenol was identified (an unlikely occurrence), concerns over possible plant contamination should not limit sludge applications to calcareous soils at agronomic rates. Rapid degradation will minimize opportunities for plant uptake of 2,4-dinitrophenol from contaminated soils or leaching of 2,4-dinitrophenol to groundwater given careful water management.

AQUATIC FATE: Based on a classification scheme(1), a Koc values of 13.5(2) and 16.6(3), indicate that 2,4-dinitrophenol is not expected to adsorb to suspended solids and sediment(SRC). A pKa of 4.09(4) indicates 2,4-dinitrophenol will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process(SRC). According to a classification scheme(5), BCFs of <0.4-0.7 and <3.7(6), suggest the bioconcentration in aquatic organisms is low(SRC). The biodegradation half-life of 2,4-dinitrophenol was reported as 68 days and 2.8 days in aerobic and anaerobic waters, respectively(7).

AQUATIC FATE: ... The high solubility of 2,4-dinitrophenol in water (5,600 mg/L at 18 °C) and its presence in solution primarily as an anion strongly favor a partitioning tendency toward water rather than air.

For more Environmental Fate (Complete) data for 2,4-Dinitrophenol (6 total), please visit the HSDB record page.

AEROBIC: 2,4-Dinitrophenol, present at 100 mg/L, reached 0% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test(1). It is reported that nitrophenols can inhibit aerobic microbial growth by uncoupling the metabolic process of oxidative phosphorylation(2). Static incubation of 5 and 10 mg/L of 2,4-dinitrophenol seeded with settled domestic wastewater resulted in 60 and 68% degradation, respectively, in 7 days(3). Oxygen uptake by mixed cultures of phenol adapted microorganisms suggests that 2,4-dinitrophenol was slowly degraded under aerobic conditions(4-5). Possible biotransformation processes of 2,4-dinitrophenol are: reduction of the nitro group, hydroxylation of the aromatic ring and displacement of the nitro group by a hydroxy group(6). A pure culture of the fungus Fusarium oxysporum was found to reduce 2,4-dinitrophenol to 2-amino-4-nitrophenol and 4-amino-2-nitrophenol(6). Nitrite release has been observed during the metabolism of 2,4-dinitrophenol by pure cultures of Nocardia alba, Arthrobacter and Corynebacterium simplex(6). The biodegradation half-life of 2,4-dinitrophenol in an acidic soil was reported as 32.1 days and the biodegradation half-life in a basic soil was reported as 4.6 days(7). The half-life for 2,4-dinitrophenol was measured in field studies to be 3-263 days at an application rate of 1.5 kg/ha, however degradation was not specified as abiotic or biodegradation(8).

The half-life of 2,4-dinitrophenol in an aquifer slurry was about 5 days under both methanogenic and sulfate-reducing conditions, but was not biodegraded under nitrate-reducing conditions(1). An activated sludge previously adapted to mineralize low concentrations of dinitrophenols resulted in 95% biodegradation of 10 mg/L of 2,4-dinitrophenol in about 4 hours, but when the substrate concentration was increased to 75 mg/L no degradation was observed over 25 hours(2). The biodegradation half-life of 2,4-dinitrophenol was reported as 68 days and 2.8 days in aerobic and anaerobic waters, respectively(3).

AEROBIC: Biodegradation studies of 2,4-dinitrophenol showed slow oxidation by cultures adapted to phenol, or dinitrophenol derivatives.

PURE CULTURE: ... Arthrobacter simplex, Pseudomonas, and Arthrobacter were able to metabolize 2,4-dinitrophenol and 2,4,6-trinitrophenol, forming nitrite.

The rate constant for the vapor-phase reaction of 2,4-dinitrophenol with photochemically-produced hydroxyl radicals has been estimated as 6.6X10-13 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 24 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 2,4-Dinitrophenol will form formic, acetic, glyoxylic and oxalic acid when ozonated, all these products are biodegradable to methane(2). 2,4-Dinitrophenol may react with nitrate radicals in the atmosphere(1). 2,4-Dinitrophenol is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). 2,4-Dinitrophenol does absorb light at wavelengths >290 nm(4) and therefore may be susceptible to direct photolysis by sunlight(SRC).

BCF values of <0.4-0.7 and <3.7 were measured in carp (Cyprinus carpio) exposed over a 6 week incubation period at 2,4-dinitrophenol concentrations of 50 and 5 ug/L, respectively(1). According to a classification scheme(2), these BCFs suggest the potential for bioconcentration in aquatic organisms is low(SRC).

2,4-Dinitrophenol has a measured Koc of 13.5 in alluvial sandy loam (7.8% clay, 30% silt, 62.2% sand, 1.1% organic matter, pH 8.1)(1). 2,4-Dinitrophenol also has a measured Koc of 16.6(2). According to a classification scheme(3), these Koc values suggest that 2,4-dinitrophenol is expected to have very high mobility in soil. The pKa of 2,4-dinitrophenol is 4.09(4), indicating that this compound will exist almost entirely in anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(5). This can be seen in the measured Koc values(SRC).

A pKa of 4.09(1) indicates 2,4-dinitrophenol will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process(SRC). 2,4-Dinitrophenol is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.9X10-4 mm Hg(2).

During 1980, 2,4-dinitrophenol was detected in sediment/water/soil samples at Love Canal(1). 2,4-Dinitrophenol has been monitored at USEPA STORET stations, 812 samples, 0.4% positive(2).

GROUNDWATER: 2,4-Dinitrophenol was detected in groundwater of Ville Mercier, Quebec, Canada at 1.5 and 11.3 ug/L(1). 2,4-Dinitrophenol was identified, not quantified, in groundwater outside of the Lipari landfill, NJ(2). 2,4-Dinitrophenol was detected in the Biscayne Aquifer, FL at 14 ug/L(3). 2,4-Dinitrophenol was detected at concentrations of 4.2-33 ug/L in groundwater at a former munitions plant in Saxony, Germany(4).

DRINKING WATER: 2,4-Dinitrophenol was identified, not quantified, in drinking water of the US(1).

SURFACE WATER: 2,4-Dinitrophenol was detected in the Potomac River, Virginia at a concentration of <10 ug/L(1). 2,4-Dinitrophenol was identified, not quantified, in 3 out of 812 USEPA STORET stations(2). 2,4-Dinitrophenol was detected in water samples from the Huaihe River, China in the summer of 2002 at a concentration of 0.10-0.40; concentrations of 0.13-0.23, and 0.13-0.20 ug/L at Xiao Zui, Huaihe River bridge, and Hongguang Chemical plant, respectively, were also reported(3). Two drinking water catchment basins in southern Portugal were tested for 2,4-dinitrophenol from Feb to Oct 2003 with water concentrations averaging 1-2 and 1-5 mg/L in Santa Clara and Roxo, respectively(4).

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number P048, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Dinitrophenol: Incinerate (1800 °F, 2.0 sec minimum) with adequate scrubbing equipment for the removal of NOx. Dinitrophenol ... /is a/ waste chemical stream constituent which may be subjected to ultimate disposal by controlled incineration. /Dinitrophenol/

A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.

Chemical Treatability of 2,4-Dinitrophenol; Concentration Process: Biological Treatment. Chemical Classification: Phenol; Scale of Study: Respirometer Study; Type of Wastewater Used: Synthetic Wastewater; Results of Study: Max oxygen uptake was 27.7 ppm of aeration.

For more Disposal Methods (Complete) data for 2,4-Dinitrophenol (8 total), please visit the HSDB record page.

/GUIDE 113: FLAMMABLE SOLIDS - TOXIC (WET/DESENSITIZED EXPLOSIVE)/ Fire or Explosion: Flammable/combustible material. May be ignited by heat, sparks or flames. DRIED OUT material may explode if exposed to heat, flame, friction or shock; treat as an explosive (GUIDE 112). Keep material wet with water or treat as an explosive (Guide 112). Runoff to sewer may create fire or explosion hazard. /Dinitrophenol, wetted with not less than 15% water/

/GUIDE 113: FLAMMABLE SOLIDS - TOXIC (WET/DESENSITIZED EXPLOSIVE)/ Health: Some are toxic and may be fatal if inhaled, swallowed or absorbed through skin. Contact may cause burns to skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may cause pollution. /Dinitrophenol, wetted with not less than 15% water/

/GUIDE 113: FLAMMABLE SOLIDS - TOXIC (WET/DESENSITIZED EXPLOSIVE)/ Public Safety: CALL Emergency Response Telephone Number. ... Isolate spill or leak area immediately for at least 100 meters (330 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Ventilate closed spaces before entering. /Dinitrophenol, wetted with not less than 15% water/

/GUIDE 113: FLAMMABLE SOLIDS - TOXIC (WET/DESENSITIZED EXPLOSIVE)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. /Dinitrophenol, wetted with not less than 15% water/

For more DOT Emergency Guidelines (Complete) data for 2,4-Dinitrophenol (16 total), please visit the HSDB record page.

UN 0076; Dinitrophenol, dry or wetted with less than 15% water, by mass[United Nations; Recommendations on the Transport of Dangerous Goods. Model Regulations. Vol. I, 16th Revised Edition (2009). Available from, as of November 22, 2010: http://www.unece.org/trans/danger/publi/unrec/rev16/16files_e.html]

UN 1320; Dinitrophenol, wetted with not less than 15% water, by mass[United Nations; Recommendations on the Transport of Dangerous Goods. Model Regulations. Vol. I, 16th Revised Edition (2009). Available from, as of November 22, 2010: http://www.unece.org/trans/danger/publi/unrec/rev16/16files_e.html]

UN 1599; Dinitrophenol solution[United Nations; Recommendations on the Transport of Dangerous Goods. Model Regulations. Vol. I, 16th Revised Edition (2009). Available from, as of November 22, 2010: http://www.unece.org/trans/danger/publi/unrec/rev16/16files_e.html]

Hazard Class or Division: 1.1D; Dinitrophenol, dry or wetted with less than 15% water, by mass[United Nations; Recommendations on the Transport of Dangerous Goods. Model Regulations. Vol. I, 16th Revised Edition (2009). Available from, as of November 22, 2010: http://www.unece.org/trans/danger/publi/unrec/rev16/16files_e.html]

For more Shipping Name/ Number DOT/UN/NA/IMO (Complete) data for 2,4-Dinitrophenol (6 total), please visit the HSDB record page.

49 166 26; Dinitrophenol solution (shipped water wet with at least 15% water)

49 214 25; Dinitrophenol solution

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Flammable Solid Poison

Unbreakable packaging. Put breakable packaging into closed unbreakable container. Do not transport with food and feedstuffs. Marine pollutant.

Symbol: T, N; R: 23/24/25-33-50; S: (1/2)-28-37-45-61

UN Hazard Class: 4.1; UN Subsidiary Risks: 6.1; UN Pack Group: I