1,1-Dichloropropane

112.99

112.99

201-165-3

SR71OVZ2OZ

0723

1993|1992

DTXSID9058818

Liquid|Colorless watery liquid

0

2.3 (calculated)

1,1-dichloropropane is a colorless watery liquid with a sweet odor. Sinks in water. Produces irritating vapor. (USCG, 1999)

1.1321 g/cm³ @ Temp: 20 °C

<25 °C

88.1 °C @ Press: 760 Torr

45 °F

n20/D 1.4275(lit.)

organic solvents: soluble(lit.)

Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Storage class (TRGS 510): Flammable liquids.

Vapour pressure, kPa at 25°C: 8.7

Relative vapour density (air = 1): 3.9

LD50 orally in rats: 6.5 g/kg (Smyth et al.)

Flammable limits in air: 3.4% - 14.5% (est)

vol% in air: 3.44.5

Sweet

Henry's Law constant = 3.76X10-3 atm-cu m/mol at 25 °C (est)

Sinks in water. Produces irritating vapor|Hydroxyl radical reaction rate constant = 8.48X10-13 cu cm/molec-sec at 25 °C (est)

Highly flammable.

Halogenated Organic Compounds

Highly Flammable

Halogenated aliphatic compounds, such as 1,1-DICHLOROPROPANE, are moderately or very reactive. Halogenated organics generally become less reactive as more of their hydrogen atoms are replaced with halogen atoms. Low molecular weight haloalkanes are highly flammable and can react with some metals to form dangerous products. Materials in this group are incompatible with strong oxidizing and reducing agents. Also, they are incompatible with many amines, nitrides, azo/diazo compounds, alkali metals, and epoxides.

1035 °F (USCG, 1999)|557 °C

-6667 Btu/lb = -3704 cal/g

The vapour is heavier than air and may travel along the ground; distant ignition possible.

Critical temperature: 266.1 °C; critical pressure = 38.3 atm

II

3.1

UN 1993 3/PG 2

3

20/21/22-36/37/38-40-11

16-26-36/37/39-45

TX9450000

F,Xn

Separated from strong oxidants, strong bases and food and feedstuffs. Cool. Well closed. Keep in a well-ventilated room.

Stable under recommended storage conditions.

P210-P261-P281-P305 + P351 + P338

H225-H315-H319-H332-H335-H351

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.|Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material. Contaminated packaging: Dispose of as unused product.

Incompatible materials: Strong oxidizing agents, strong bases.

USEPA; Ambient Water Quality Criteria Doc: Dichloropropenes and Dichloropropanes (1980)

Special Hazards of Combustion Products: Emits fumes of phosgene (USCG, 1999)|Highly flammable. Heating will cause rise in pressure with risk of bursting. Gives off irritating or toxic fumes (or gases) in a fire. Vapour/air mixtures are explosive.

|Danger|H225 (92.68%): Highly Flammable liquid and vapor [Danger Flammable liquids]|P201, P202, P210, P233, P240, P241, P242, P243, P261, P264, P271, P280, P281, P302+P352, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P308+P313, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P403+P235, P405, and P501|Aggregated GHS information provided by 41 companies from 2 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H225: Highly Flammable liquid and vapor [Danger Flammable liquids]|P201, P202, P210, P233, P240, P241, P242, P243, P261, P264, P271, P273, P280, P281, P302+P352, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P308+P313, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P403+P235, P405, and P501

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet). FIRE: If tank, rail car or tank truck 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, 2016)

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material. LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2016)

Rubber gloves, self-contained breathing apparatus, coveralls or laboratory coat. (USCG, 1999)|Eye/face protection: Face shield and safety glasses. Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).|Skin protection: Handle with gloves.|Body Protection: Complete suit protecting against chemicals. Flame retardant antistatic protective clothing. The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.|Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multipurpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).|Breakthrough times for dichloropropane on chlorinated polyethylene are less (usually significantly) than one hour as reported by two or more testers.

A very dangerous fire hazard when exposed to heat, flame, or oxidizers.

Explosive limits , vol% in air: 3.4-14.5

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.|Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up: Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapors accumulating to form explosive concentrations. Vapors can accumulate in low areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.|Precautions for safe handling: Avoid contact with skin and eyes. Avoid inhalation of vapor or mist. Use explosion-proof equipment. Keep away from sources of ignition - No smoking. Take measures to prevent the build up of electrostatic charge.|Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.|Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.|SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

An eye irritant.

Evacuate danger area! Personal protection: filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Ventilation. Collect leaking liquid in sealable containers. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Do NOT wash away into sewer.

Separated from strong oxidants, strong bases and food and feedstuffs. Cool. Well closed. Keep in a well-ventilated room.

No indication can be given about the rate at which a harmful concentration of this substance in the air is reached on evaporation at 20 °C.

The substance is irritating to the eyes and skin.

NO open flames, NO sparks and NO smoking. Closed system, ventilation, explosion-proof electrical equipment and lighting.

PREVENT GENERATION OF MISTS!

Use ventilation, local exhaust or breathing protection.

Protective gloves.

Wear safety spectacles.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 1,000 lb or 454 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

URBAN/SUBURBAN: 1,1-Dichloropropane was detected, not quantified in ambient air samples from Hoboken, NJ in March of 1976(1).

IDENTIFICATION AND USE: 1,1-Dichloropropane is a liquid. It is used as a solvent for pesticide formulations. HUMAN STUDIES: Inhalation of a high vapor concentration can result in gasping, refusal to breathe, coughing, substernal pain, and extreme respiratory distress at vapor concentration over 1500 ppm. Irritation of eyes and upper respiratory mucosa appears promptly after exposure to concentrated vapors. Lacrimation and headache are prominent. Coma may occur rapidly. Inhalation of a low vapor concentration may cause central nervous depression and moderate irritation of respiratory system. Headache is frequent. Dermal exposure causes severe skin irritation with marked inflammatory response of epidermis and underlying tissues. Oral exposure may lead to acute gastrointestinal distress with pulmonary congestion and edema, as well as central nervous depression, perhaps even in the absence of impaired oxygen uptake. Exposure by any route may cause possible late injuries to liver, kidneys and heart. After inhalation exposures, malaise, headache, chest and abdominal discomfort and irritability have been reported to persist for several weeks and perhaps for several years. ANIMAL STUDIES: It was tested externally on eyes of rabbits and rated 2 on scale of 1-10 according to degree of injury observed after 24 hr, paying particular attention to condition of cornea. Most severe injuries have rated 10.

LD50 Rat oral 6500 mg/kg|LD50 Rabbit skin 14 g/kg

1,1-Dichloropropane's production and use as a laboratory chemical and a chemical intermediate(1,2) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 61(SRC), determined from a structure estimation method(2), indicates that 1,1,-dichloropropane is expected to have high mobility in soil(SRC). Volatilization of 1,1,-dichloropropane from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 3.8X10-3 atm-cu m/mole(SRC), based upon its vapor pressure, 68.3 mm Hg(3), and water solubility, 2,700 mg/L(4). 1,1,-Dichloropropane is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). 1,1-Dichloropropane was degraded by an anaerobic enrichment culture able to reductively dechlorinate 1,2-dichloropropane(5); however, biodegradation is not expected to be an important environmental fate process in soil(SRC).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 61(SRC), determined from a structure estimation method(2), indicates that 1,1,-dichloropropane is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 3.8X10-3 atm-cu m/mole(SRC), derived from its vapor pressure, 68.3 mm Hg(4), and water solubility, 2,700 mg/L(5). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 3 hrs and 4 days, respectively(SRC). According to a classification scheme(6), an estimated BCF of 14(SRC), from an estimated log Kow of 2.25(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Alkyl halides are susceptible to neutral and basic hydrolysis, but additional halides on a carbon atom markedly decreases the hydrolysis rate(7). 1,1-Dichloropropane was degraded by an anaerobic enrichment culture able to reductively dechlorinate 1,2-dichloropropane(8); however, biodegradation is not expected to be an important environmental fate process in water(SRC).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,1,-dichloropropane, which has a vapor pressure of 68.3 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1,1,-dichloropropane is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 19 days(SRC), calculated from its rate constant of 8.5X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 1,1,-Dichloropropane does not contain chromophores that absorb at wavelengths >290 nm(4) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of 1,1,-dichloropropane with photochemically-produced hydroxyl radicals has been estimated as 8.5X10-13 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of 19 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Alkyl halides are susceptible to neutral and basic hydrolysis, but additional halides on a carbon atom markedly decreases the hydrolysis rate(2). The hydrolysis half-life of analogous n-propyl chloride is 69 days at pH 7 and 25 °C(2), suggesting that half-life of 1,1-dichloropropane would be much longer and, therefore, not an important environmental fate process(SRC). 1,1,-Dichloropropane does not contain chromophores that absorb at wavelengths >290 nm(3) and, therefore, is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 14 was calculated in fish for 1,1,-dichloropropane(SRC), using an estimated log Kow of 2.25(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 1,1,-dichloropropane can be estimated to be 61(SRC). According to a classification scheme(2), this estimated Koc value suggests that 1,1,-dichloropropane is expected to have high mobility in soil(SRC).

The Henry's Law constant for 1,1-dichloropropane is estimated as 3.8X10-3 atm-cu m/mole(SRC) derived from its vapor pressure, 68.3 mm Hg(1), and water solubility, 2,700 mg/L(2). This Henry's Law constant indicates that 1,1-dichloropropane is expected to volatilize from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 3 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 4 days(SRC). 1,1-Dichloropropane's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of 1,1-dichloropropane from dry soil surfaces may exist(SRC) based upon its vapor pressure(1).

DRINKING WATER: 1,1-Dichloropropane was detected at a total concentration of 2.5 ug/L in samples from 21 public drinking water fountains in Torino, Italy, tested in December 1994. It was not detected in May 1995 samples from 10 fountains(1).|SURFACE WATER: In a USGS survey of the Delaware River estuary and selected New Jersey tributaries, May 1980 to Jan 1981, 1,1-dichloropropane was only detected in September 1980 in the vicinity of Philadelphia, PA at 3.0-5.0 ppb(1).

Occupational exposure to 1,1-dichloropropane may occur through inhalation and dermal contact with this compound at workplaces where 1,1-dichloropropane is produced or used. The general public is not expected to be exposed to 1,1-dichloropropane. (SRC)|Inhalation of vapor, ingestion, eye, and skin contact.

(36)Chloride labeled chloropropanes such as 1,1-dichloropropane were enzymatically dechlorinated by enzyme system located in rabbit, rat, and guinea pig liver microsomes. System required NADPH and oxygen and was inducible by phenobarbital or benzo(a)pyrene but not methylcholanthrene. The optimum pH of the system was 8.2.

INHALATION: May cause some central nervous system depression. EYES: May cause some pain and irritation. SKIN: Mild irritation. (USCG, 1999)

Call a doctor. INHALATION: Remove to fresh air. If breathing has stopped, give artificial respiration. EYES: Flush with running water for 15 minutes. SKIN: Wash thoroughly with soap and water. INGESTION: Gastric lavage or emesis and catharsis. (USCG, 1999)

Fresh air, rest.

First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again.

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

Immediate first aid: Remove patient from contact with the material. Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Dichloropropane, dichloropropene, and related compounds/|Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Cover skin burns with dry sterile dressings after decontamination ... . /Dichloropropane, dichloropropene, and related compounds/|Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Dichloropropane, dichloropropene, and related compounds/|1. FLUSH contaminating fumigants from the skin and eyse with copious amounts of water or saline for at least 15 minutes. Some fumigants are corrosive to the cornea and may cause BLINDNESS. Specialized medical treatment should be obtained promptly following removal of toxicant by copious flushing with clean water. Skin contamination may cause BLISTERING and deep chemical burns. Absorption of some fumigants across the skin may be sufficient to cause systemic poisoning in the absence of fumigant inhalation. For all these reasons, decontamination of eyes and skin must must be IMMEDIATE and THROUGH. 2. REMOVE victims of fumigant inhalation to FRESH AIR immediately. Even though initial symptoms and signs are mild, keep the victim quiet, in a semi-reclining position. Minimum pohysical activity limits the likehood ofpulmonary edema. 3. If victim is not breathing, clear the airway of secretions and RESUSCITATE with positive poressure oxygen apparatus. If this is not available, use chest compression to sustain respiration. If victim is pulseless, employ cardiac resuscitation. 4. If PULMONARY EDEMA is evident, there are several measures avilable to sustain life. Medical judgement must be relied upon, however, in the management of each case. The following procedures are generally recommended: A. Put the victim in a SITTING position with a backrest. B. Use intermittent and/or continuous positive pressure OXYGEN to relieve hypoxemia. ... C. Slowly administer FUROSEMIDE, 40 mg, or SODIUM ETHACRYNATE, 50 mg, to reduce venous load by inducing diuresis. ... D. Morphine in small doses (5-10 mg), slowly, iv to allay anxiety and promote deeper respiratory excursions. E. Administer AMINOPHYLLINE (0.25-0.50 gm) slowly, iv. ... F. Digitalization may be considered, but there is a serious risk of arrhythmias in an anoxic and toxic myocardium. G. TRACHEOSTOMY may be necessary in some cases to facilitate aspiration of large amounts of pulmonary edema fluid. H. Epinephrine, atorpine, and expectorants are generally not helpful, and may complicate treatment. I. Watch for RECURRENT PULMONARY EDEMA, even up to 2 weeks after the initial episode. Limit victim's physical activity for at least 4 weeks. Severe physical weakness usually indicates persistent pulmonary injury. Serial pulmonary function testing may be useful in assessing recovery. 5. Combat SHOCK by placing victim in the Trendelenburg position and administering plasma, whole blood, and/or electrolyte and glucose solutions intravenously, with great care, to avoid pulmonary edema. Central venous pressure should be monitored continously. Vasopressor amines must be given with great caution, because of the irritability of the myocardium. 6. Control CONVULSIONS. Seizures are most likely to occur in poisonings by methyl bromide, hydrogen cyanide, acrylonitrile, phosphine, and carbon disulfide. ... /Fumigant poisoning/|For more Antidote and Emergency Treatment (Complete) data for 1,1-Dichloropropane (6 total), please visit the HSDB record page.

/SIGNS AND SYMPTOMS/ 1A) Inhalation, high vapor concentration: gasping, refusal to breathe, coughing, substernal pain, and extreme respiratory distress at vapor concentration over 1500 ppm. Irritation of eyes and upper respiratory mucosa appears promptly after exposure to concentrated vapors. Lacrimation and headache are prominent. Coma may occur rapidly. B) Inhalation, low vapor concentration: central nervous depression and moderate irritation of respiratory system. Headache is frequent. 2) Dermal: severe skin irritation with marked inflammatory response of epidermis and underlying tissues. 3) Oral: acute gastrointestinal distress with pulmonary congestion and edema. Central nervous depression, perhaps even in the absence of impaired oxygen uptake. 4) By any route, possible late injuries to liver, kidneys and heart. 5) After inhalation exposures, malaise, headache, chest and abdominal discomfort and irritability have been reported to persist for several weeks and perhaps for several years.

The substance can be absorbed into the body by inhalation.

Dizziness.

Redness. Pain.

Redness. Pain.

SRP: Contaminant of 1,2-dichloropropane.

Purge-and-trap analysis using fused silica capillary column gas chromatography/mass spectrometry was evaluated for the analysis of priority pollutants. Using EPA volatile organic performance evaluation samples, WP006 & WP007 as unknown test materials, satisfactory precision (8.5%) & excellent accuracy (98.5% & 102% recoveries) were achieved. The capillary column was much faster than the packed column (13 min compared to 33 min) & overcame difficulties normally encountered with samples having excessive complexity, very large concn spread among components, or high concn of high-boiling components.