2,5-dichloronitrobenzene

H350: May cause cancer [Danger Carcinogenicity]

P203, P280, P318, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for 1.1% (1 of 94) of reports.

H302 (98.9%): Harmful if swallowed [Warning Acute toxicity, oral]

H317 (43.6%): May cause an allergic skin reaction [Warning Sensitization, Skin]

H319 (93.6%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H341 (46.8%): Suspected of causing genetic defects [Warning Germ cell mutagenicity]

H411 (53.2%): Toxic to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

H412 (42.6%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P203, P261, P264, P264+P265, P270, P272, P273, P280, P301+P317, P302+P352, P305+P351+P338, P318, P321, P330, P333+P317, P337+P317, P362+P364, P391, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 94 reports by companies from 9 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 94 reports by companies.

There are 8 notifications provided by 93 of 94 reports by companies with hazard statement code(s).

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.

H302: Harmful if swallowed [Warning Acute toxicity, oral]

H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H351: Suspected of causing cancer [Warning Carcinogenicity]

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

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

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

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

P203, P260, P261, P264, P270, P271, P280, P301+P317, P304+P340, P308+P316, P318, P319, P321, P330, P403+P233, P405, and P501 (click each P-code to see the statement)

H316: Causes mild skin irritation [Warning Skin corrosion/irritation]

H317: May cause an allergic skin reaction [Warning Sensitization, Skin]

H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]

P203, P260, P261, P264, P264+P265, P270, P271, P272, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P308+P316, P318, P319, P321, P330, P332+P317, P333+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)

P203, P260, P264, P264+P265, P270, P280, P301+P317, P305+P351+P338, P318, P319, P330, P337+P317, P405, and P501 (click each P-code to see the statement)

Fresh air, rest.

Rinse and then wash skin with water and soap. Refer for medical attention .

Rinse with plenty of water (remove contact lenses if easily possible).

Rinse mouth. Refer for medical attention .

Use water spray, dry powder, foam, carbon dioxide.

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance, protective clothing, protective gloves and face shield. Do NOT let this chemical enter the environment. Sweep spilled substance into sealable containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. 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 soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

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.

Separated from bases, strong oxidants and food and feedstuffs. Store in an area without drain or sewer access. Provision to contain effluent from fire extinguishing.

A harmful concentration of airborne particles can be reached quickly when dispersed, especially if powdered.

The substance may have effects on the liver and kidneys, resulting in impaired functions. This substance is possibly carcinogenic to humans.

NO open flames.

PREVENT DISPERSION OF DUST! STRICT HYGIENE!

Use ventilation (not if powder).

Protective gloves.

Wear safety spectacles.

Do not eat, drink, or smoke during work.

Yellow solid; [ICSC] Yellow crystals; [Sigma-Aldrich MSDS]

YELLOW FLAKES.

Plates or prisms from alcohol, plates from ethyl acetate

In water, 95 mg/L at 25 °C

In water, 92.1 mg/L at 20 °C

Soluble in ethanol, ether, benzene, carbon disulfide; slightly soluble in carbon tetrachloride

Solubility in water, g/100ml at 20 °C: 0.01 (very slightly soluble)

1.669 at 22 °C

Density: 1.479 g/cu cm at 75 °C

1.67 g/cm³

Relative density of the vapour/air-mixture at 20 °C (air = 1): 1.00

Relative vapor density (air = 1): 6.6

0.00505 [mmHg]

0.00383 mm Hg at 25 °C

Vapor pressure, Pa at 25 °C: 0.5

log Kow = 3.09

Henry's Law constant = 1.5X10-5 atm-cu m/mol at 25 °C

When heated to decomposition it emits very toxic fumes of /hydrogen chloride and nitrogen oxides/.

pH = 6.9 (80 mg/L water) at 20 °C

6.6 (Air = 1)

Index of refraction: 1.4390 at 75 °C

log Kow = 2.93 at 25 °C (OECD TG 107)

Crystal structure

Formula unit

Nuclear quadrupole resonance spectroscopy

Optical coefficient

Quadrupole coupling

Refractive index

Space group

Surface tension

Unit cell

Unit cell parameter

Nitrogen Compounds -> Nitros, Aromatic

1,4-Dichloro-2-nitrobenzene

Group 2B: Possibly carcinogenic to humans

Volume 65: (1996) Printing Processes and Printing Inks, Carbon Black and Some Nitro Compounds

Volume 123: (2020) Some Nitrobenzenes and Other Industrial Chemicals

2020 online

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

Redness.

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.

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

IARC Carcinogen - Class 3: Chemicals are not classifiable by the International Agency for Research on Cancer.

LD50 Mouse oral 2850 mg/kg

LD50 Rat oral 1210 mg/kg

LD50 Rat dermal > 2,000 mg/kg

/SRP:/ Immediate first aid: 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 if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the 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. /Poisons A and B/

/SRP:/ 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 needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures 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 ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/

/SRP:/ 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 as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/

/OTHER TOXICITY INFORMATION/ 1,4-Dichloro-2-nitrobenzene is mildly irritating to eyes and non-irritating to skin. When tested in animals the product has been proved to be a non-sensitizer; however, there are indications of skin sensitization in man.

/LABORATORY ANIMALS: Acute Exposure/ No effect has been observed following 7-hour inhalation exposure of rats to air saturated with 1,4-dichloro-2-nitrobenzene (47.6 mg/cu m (nominal concentration) and 2 to 39 mg/cu m (measured concentration)).

/LABORATORY ANIMALS: Acute Exposure/ 1,4-Dichloro-2-nitrobenzene given orally to cats causes methemoglobin formation (a maximum of 9.1 % was observed after 24 hours at 250 mg/kg body weight).

/LABORATORY ANIMALS: Acute Exposure/ Following oral administration to rats the value for the acute toxicity (LD 50) was 2503 mg/kg body weight; another study yielded a LD 50 value of 1210 mg/kg body weight. Disturbance of equilibrium and palmospasms have been observed as symptoms of acute intoxication.

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ The repeated oral administration of subacute doses (10, 50 and 250 mg/kg body weight and day) to rats by gavage for 28 days causes increased liver weights and bilirubin values. In male animals at 250 mg/kg body weight and day decrease in the weight of testes, lack of mature sperma and signs of germinal epithel lesions, and in female animals from 50 mg/kg body weight and day onward ulcera of the forestomach have been observed. The no-observed-effect level (NOEL) was 10 mg/kg body weight and day.

For more Non-Human Toxicity Excerpts (Complete) data for 1,4-Dichloro-2-nitrobenzene (12 total), please visit the HSDB record page.

EC50; Species: Chlorella pyrenoidosa (Green Algae) exponential growth phase, 2 X10+8 cells/mL; Conditions: freshwater, static, 25 °C, pH 6.6; Concentration: 2100 ug/L for 96 hr (95% confidence interval: 1500-2800 ug/L); Effect: growth, general />98% purity formulation/

LC50; Species: Daphnia magna (Water Flea) age <24 hr; Conditions: freshwater, static, 20 °C, pH 8.2, hardness 250 mg/L CaCO3. dissolved oxygen >6.5 mg/L; Concentration: 11000 ug/L for 48 hr (95% confidence interval: 5600-18000 ug/L) />98% purity formulation/

LC50; Species: Daphnia magna (Water Flea) age <24 hr; Conditions: freshwater, static, 20 °C, pH 8.2, hardness 250 mg/L CaCO3. dissolved oxygen >6.5 mg/L; Concentration: 3800 ug/L for 21 days (95% confidence interval: 3600-4000 ug/L) />98% purity formulation/

LC50; Species: Poecilia reticulata (Guppy) age 3-4 weeks; Conditions: freshwater, static, 25 °C, pH 8.2, hardness 250 mg/L CaCO3; Concentration: 4900 ug/L for 14 days />98% purity formulation/

For more Ecotoxicity Values (Complete) data for 1,4-Dichloro-2-nitrobenzene (6 total), please visit the HSDB record page.

/AQUATIC SPECIES/ Following the exposure of algae (Chlorella pyrenoidosa) for 96 hours to 2.1 mg/L, 50% inhibition of growth has been observed... For water fleas (Daphnia magna), 48-hr EC50 value (immobilization) amounts to 11 mg/L and the 21-day EC50 value to 3.8 mg/L. In a semi-static 21-day reproduction test the lowest concentrations at which the population growth rate and mean length of the animals significantly (p<0.01) decreased were 1.8 mg/L and 3.2 mg/L respectively. For fish (Leuciscus idus), the value of acute toxicity (96-hr LC50) in an open system under semi-static conditions is 6.3 mg/L and the corresponding value (48-hr LC50) in a closed system under static conditions is 4.5 mg/L. The lowest 96-hr LC0 was 3.15 mg/L. In the prolonged fish toxicity test under semi-static conditions a 14 day LC50 value of 4.9 mg/L has been found for Poecilia reticulata.

/PLANTS/ 1,4-Dichloro-2-nitrobenzene at concentrations > 42.2 mg/L is phytotoxic (6-day EC50; reduction in fresh weight) to higher plants (seedlings of cucumber and bean).

The substance is toxic to aquatic organisms. The substance may cause long-term effects in the aquatic environment. It is strongly advised not to let the chemical enter into the environment.

1,4-Dichloro-2-nitrobenzene's production and use in the manufacture of dyestuff intermediates, pesticides and UV absorbents may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 0.00383 mm Hg at 25 °C indicates 1,4-dichloro-2-nitrobenzene will exist solely as a vapor in the atmosphere. Vapor-phase 1,4-dichloro-2-nitrobenzene 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 320 days. 1,4-Dichloro-2-nitrobenzene absorbs UV light above 290 nm and therefore is photodegraded in sunlight. If released to soil, 1,4-dichloro-2-nitrobenzene is expected to have low mobility based upon an estimated Koc of 590. Volatilization from moist soil surfaces is expected to occur based upon a Henry's Law constant of 1.5X10-5 atm-cu m/mole. Photodegradation is expected to occur on surfaces exposed to sunlight. Utilizing the Japanese MITI test, 4% of the theoretical BOD was reached in four weeks indicating that biodegradation is not an important environmental fate process in soil or water. If released into water, 1,4-dichloro-2-nitrobenzene is expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is expected to be an important fate process based upon this compound's Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 4.4 and 36 days, respectively. An observed BCF range of 18-118 in carp and rainbow trout suggest bioconcentration in aquatic organisms is low to moderate. Photodegradation in water is expected to occur; an estimated direct photolysis half-life of 34 days can be made for a model body of water 500 cm deep. Abiotic hydrolysis does not occur in the environment. Occupational exposure to 1,4-dichloro-2-nitrobenzene may occur through dermal contact with this compound at workplaces where 1,4-dichloro-2-nitrobenzene is produced or used. 1,4-Dichloro-2-nitrobenzene is not contained in consumer products; therefore, exposure to the general population will not occur via contact with consumer products. (SRC)

1,4-Dichloro-2-nitrobenzene's production and use in the manufacture of dyestuff intermediates, pesticides and UV absorbents(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 590(SRC), determined from a structure estimation method(2), indicates that 1,4-dichloro-2-nitrobenzene is expected to have low mobility in soil(SRC). Volatilization of 1,4-dichloro-2-nitrobenzene from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 1.5X10-5 atm-cu m/mole(3). 1,4-Dichloro-2-nitrobenzene is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.00383 mm Hg at 25 °C(4). 1,4-Dichloro-2-nitrobenzene absorbs UV light above 290 nm and will photodegrade in sunlight(4). Utilizing the Japanese MITI test, 4% of the theoretical BOD was reached in four weeks(5) indicating that biodegradation is not an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 590(SRC), determined from a structure estimation method(2), indicates that 1,4-dichloro-2-nitrobenzene is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 1.5X10-5 atm-cu m/mole at 25 °C(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 4.4 and 36 days, respectively(SRC). According to a classification scheme(5), observed BCF values of 18-118, measured in carp and rainbow trout(6,7), suggests the potential for bioconcentration in aquatic organisms is low to moderate(SRC). 1,4-Dichloro-2-nitrobenzene has an epilson of 0.00126 at 300 nm in aqueous solution(8) which indicates the compound may be susceptible to direct photolysis(SRC); an approximated quantum yield of 0.01 can be used to estimate a half-life of 34 days in a model sunlit body of water with a 500 cm depth(2). In an aqueous hydrolysis test (OECD Test guideline 111), benzene, 1,4-dichloro-2-nitro was stable to abiotic hydroylsis at pHs 4, 7 and 9 at 25 °C(8). Utilizing the Japanese MITI test, 4% of the theoretical BOD was reached in four weeks(6) indicating that biodegradation is not 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), 1,4-dichloro-2-nitrobenzene, which has a vapor pressure of 0.00383 mm Hg at 25 °C(2), expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1,4-dichloro-2-nitrobenzene 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 320 days(SRC), calculated from its rate constant of 5X10-14 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 1,4-Dichloro-2-nitrobenzene absorbs UV light above 290 nm and therefore is photodegraded in sunlight(2).

AEROBIC: 1,4-Dichloro-2-nitrobenzene, present at 100 mg/L, reached 4% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test which suggests the compound is not readily biodegradable(1).

The rate constant for the vapor-phase reaction of 1,4-dichloro-2-nitrobenzene with photochemically-produced hydroxyl radicals has been estimated as 5X10-14 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 320 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Using sunlight as the irradiation source, 1,4-dichloro-2-nitrobenzene had an epilson of 0.00126 at 300 nm in aqueous solution(2) which indicates the compound may be susceptible to direct photolysis(SRC); an approximated quantum yield of 0.01 can be used to estimate a half-life of 34 days in a model sunlit body of water with a 500 cm depth(2). In an aqueous hydrolysis test (OECD Test guideline 111), 1,4-dichloro-2-nitrobenzene was stable to abiotic hydroylsis at pHs 4, 7 and 9 at 25 °C(2).

BCF values of 18-103 were measured for 1,4-dichloro-2-nitrobenzene in carp (Cyprinus carpio) at concentrations of 5-50 ug/L over a 6-week exposure period(1). A mean 1,4-dichloro-2-nitrobenzene BCF of 118 was measured in rainbow trout over a 36-day exposure period(2). According to a classification scheme(3), these BCF values suggest the potential for bioconcentration in aquatic organisms is low to moderate(SRC). In a static container 3-day exposure test, a BCF of 1047 was measured in guppies (Poecilla reticulata)on a fat-weight basis(4).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 1,4-dichloro-2-nitrobenzene can be estimated to be 590(SRC). According to a classification scheme(2), this estimated Koc value suggests that 1,4-dichloro-2-nitrobenzene is expected to have low mobility in soil. 1,4-Dichloro-2-nitrobenzene did not leach in column leachate tests designed to assess leaching potential from wastes in landfill sites(3).

The Henry's Law constant for 1,4-dichloro-2-nitrobenzene is 1.5X10-5 atm-cu m/mole(1). This Henry's Law constant indicates that 1,4-dichloro-2-nitrobenzene is expected to volatilize from water surfaces(2). 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)(2) is estimated as 4.4 days 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)(2) is estimated as 36 days(SRC). 1,4-Dichloro-2-nitrobenzene's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 1,4-Dichloro-2-nitrobenzene is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.00383 mm Hg at 25 °C(3).

EC50; Species: Chlorella pyrenoidosa (Green Algae) exponential growth phase, 2 X10+8 cells/mL; Conditions: freshwater, static, 25 °C, pH 6.6; Concentration: 2100 ug/L for 96 hr (95% confidence interval: 1500-2800 ug/L); Effect: growth, general />98% purity formulation/

LC50; Species: Daphnia magna (Water Flea) age <24 hr; Conditions: freshwater, static, 20 °C, pH 8.2, hardness 250 mg/L CaCO3. dissolved oxygen >6.5 mg/L; Concentration: 11000 ug/L for 48 hr (95% confidence interval: 5600-18000 ug/L) />98% purity formulation/

LC50; Species: Daphnia magna (Water Flea) age <24 hr; Conditions: freshwater, static, 20 °C, pH 8.2, hardness 250 mg/L CaCO3. dissolved oxygen >6.5 mg/L; Concentration: 3800 ug/L for 21 days (95% confidence interval: 3600-4000 ug/L) />98% purity formulation/

LC50; Species: Poecilia reticulata (Guppy) age 3-4 weeks; Conditions: freshwater, static, 25 °C, pH 8.2, hardness 250 mg/L CaCO3; Concentration: 4900 ug/L for 14 days />98% purity formulation/

For more Ecotoxicity Values (Complete) data for 1,4-Dichloro-2-nitrobenzene (6 total), please visit the HSDB record page.

/AQUATIC SPECIES/ Following the exposure of algae (Chlorella pyrenoidosa) for 96 hours to 2.1 mg/L, 50% inhibition of growth has been observed... For water fleas (Daphnia magna), 48-hr EC50 value (immobilization) amounts to 11 mg/L and the 21-day EC50 value to 3.8 mg/L. In a semi-static 21-day reproduction test the lowest concentrations at which the population growth rate and mean length of the animals significantly (p<0.01) decreased were 1.8 mg/L and 3.2 mg/L respectively. For fish (Leuciscus idus), the value of acute toxicity (96-hr LC50) in an open system under semi-static conditions is 6.3 mg/L and the corresponding value (48-hr LC50) in a closed system under static conditions is 4.5 mg/L. The lowest 96-hr LC0 was 3.15 mg/L. In the prolonged fish toxicity test under semi-static conditions a 14 day LC50 value of 4.9 mg/L has been found for Poecilia reticulata.

/PLANTS/ 1,4-Dichloro-2-nitrobenzene at concentrations > 42.2 mg/L is phytotoxic (6-day EC50; reduction in fresh weight) to higher plants (seedlings of cucumber and bean).

The substance is toxic to aquatic organisms. The substance may cause long-term effects in the aquatic environment. It is strongly advised not to let the chemical enter into the environment.

1,4-Dichloro-2-nitrobenzene's production and use in the manufacture of dyestuff intermediates, pesticides and UV absorbents may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 0.00383 mm Hg at 25 °C indicates 1,4-dichloro-2-nitrobenzene will exist solely as a vapor in the atmosphere. Vapor-phase 1,4-dichloro-2-nitrobenzene 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 320 days. 1,4-Dichloro-2-nitrobenzene absorbs UV light above 290 nm and therefore is photodegraded in sunlight. If released to soil, 1,4-dichloro-2-nitrobenzene is expected to have low mobility based upon an estimated Koc of 590. Volatilization from moist soil surfaces is expected to occur based upon a Henry's Law constant of 1.5X10-5 atm-cu m/mole. Photodegradation is expected to occur on surfaces exposed to sunlight. Utilizing the Japanese MITI test, 4% of the theoretical BOD was reached in four weeks indicating that biodegradation is not an important environmental fate process in soil or water. If released into water, 1,4-dichloro-2-nitrobenzene is expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is expected to be an important fate process based upon this compound's Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 4.4 and 36 days, respectively. An observed BCF range of 18-118 in carp and rainbow trout suggest bioconcentration in aquatic organisms is low to moderate. Photodegradation in water is expected to occur; an estimated direct photolysis half-life of 34 days can be made for a model body of water 500 cm deep. Abiotic hydrolysis does not occur in the environment. Occupational exposure to 1,4-dichloro-2-nitrobenzene may occur through dermal contact with this compound at workplaces where 1,4-dichloro-2-nitrobenzene is produced or used. 1,4-Dichloro-2-nitrobenzene is not contained in consumer products; therefore, exposure to the general population will not occur via contact with consumer products. (SRC)

1,4-Dichloro-2-nitrobenzene's production and use in the manufacture of dyestuff intermediates, pesticides and UV absorbents(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 590(SRC), determined from a structure estimation method(2), indicates that 1,4-dichloro-2-nitrobenzene is expected to have low mobility in soil(SRC). Volatilization of 1,4-dichloro-2-nitrobenzene from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 1.5X10-5 atm-cu m/mole(3). 1,4-Dichloro-2-nitrobenzene is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.00383 mm Hg at 25 °C(4). 1,4-Dichloro-2-nitrobenzene absorbs UV light above 290 nm and will photodegrade in sunlight(4). Utilizing the Japanese MITI test, 4% of the theoretical BOD was reached in four weeks(5) indicating that biodegradation is not an important environmental fate process in soil(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 590(SRC), determined from a structure estimation method(2), indicates that 1,4-dichloro-2-nitrobenzene is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 1.5X10-5 atm-cu m/mole at 25 °C(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 4.4 and 36 days, respectively(SRC). According to a classification scheme(5), observed BCF values of 18-118, measured in carp and rainbow trout(6,7), suggests the potential for bioconcentration in aquatic organisms is low to moderate(SRC). 1,4-Dichloro-2-nitrobenzene has an epilson of 0.00126 at 300 nm in aqueous solution(8) which indicates the compound may be susceptible to direct photolysis(SRC); an approximated quantum yield of 0.01 can be used to estimate a half-life of 34 days in a model sunlit body of water with a 500 cm depth(2). In an aqueous hydrolysis test (OECD Test guideline 111), benzene, 1,4-dichloro-2-nitro was stable to abiotic hydroylsis at pHs 4, 7 and 9 at 25 °C(8). Utilizing the Japanese MITI test, 4% of the theoretical BOD was reached in four weeks(6) indicating that biodegradation is not 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), 1,4-dichloro-2-nitrobenzene, which has a vapor pressure of 0.00383 mm Hg at 25 °C(2), expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1,4-dichloro-2-nitrobenzene 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 320 days(SRC), calculated from its rate constant of 5X10-14 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 1,4-Dichloro-2-nitrobenzene absorbs UV light above 290 nm and therefore is photodegraded in sunlight(2).

AEROBIC: 1,4-Dichloro-2-nitrobenzene, present at 100 mg/L, reached 4% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test which suggests the compound is not readily biodegradable(1).

The rate constant for the vapor-phase reaction of 1,4-dichloro-2-nitrobenzene with photochemically-produced hydroxyl radicals has been estimated as 5X10-14 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 320 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Using sunlight as the irradiation source, 1,4-dichloro-2-nitrobenzene had an epilson of 0.00126 at 300 nm in aqueous solution(2) which indicates the compound may be susceptible to direct photolysis(SRC); an approximated quantum yield of 0.01 can be used to estimate a half-life of 34 days in a model sunlit body of water with a 500 cm depth(2). In an aqueous hydrolysis test (OECD Test guideline 111), 1,4-dichloro-2-nitrobenzene was stable to abiotic hydroylsis at pHs 4, 7 and 9 at 25 °C(2).

BCF values of 18-103 were measured for 1,4-dichloro-2-nitrobenzene in carp (Cyprinus carpio) at concentrations of 5-50 ug/L over a 6-week exposure period(1). A mean 1,4-dichloro-2-nitrobenzene BCF of 118 was measured in rainbow trout over a 36-day exposure period(2). According to a classification scheme(3), these BCF values suggest the potential for bioconcentration in aquatic organisms is low to moderate(SRC). In a static container 3-day exposure test, a BCF of 1047 was measured in guppies (Poecilla reticulata)on a fat-weight basis(4).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 1,4-dichloro-2-nitrobenzene can be estimated to be 590(SRC). According to a classification scheme(2), this estimated Koc value suggests that 1,4-dichloro-2-nitrobenzene is expected to have low mobility in soil. 1,4-Dichloro-2-nitrobenzene did not leach in column leachate tests designed to assess leaching potential from wastes in landfill sites(3).

The Henry's Law constant for 1,4-dichloro-2-nitrobenzene is 1.5X10-5 atm-cu m/mole(1). This Henry's Law constant indicates that 1,4-dichloro-2-nitrobenzene is expected to volatilize from water surfaces(2). 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)(2) is estimated as 4.4 days 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)(2) is estimated as 36 days(SRC). 1,4-Dichloro-2-nitrobenzene's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 1,4-Dichloro-2-nitrobenzene is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.00383 mm Hg at 25 °C(3).

SURFACE WATER: 1,4-Dichloro-2-nitrobenzene was not detected (detection limit of 0.07 ng/L) in water samples collected from open waters of the North Sea in July 1993(1). 1,4-Dichloro-2-nitrobenzene was not detected (detection limit of 10 ng/L) in water samples collected from the Elbe River in Germany in 1992/1993(2).

1,4-Dichloro-2-nitrobenzene was detected in zebra mussels (Dreissena polymorpha) collected from the Rhine-Meuse delta in 1994 at concentrations of 0.021-0.030 mg/kg wet weight(1).

Occupational exposure to 1,4-dichloro-2-nitrobenzene may occur through dermal contact with this compound at workplaces where 1,4-dichloro-2-nitrobenzene is produced or used(SRC). 1,4-Dichloro-2-nitrobenzene is not contained in consumer products(1); therefore, exposure to the general population will not occur via contact with consumer products(SRC).

For indirect exposure to 1,4-dichloro-2-nitrobenzene via the environment, the daily intake through drinking water is estimated to be 2.6X10-5 mg/kg/day and through fish is calculated as 1.2X10-3 mg/kg/day(1).

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. 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 soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Do not transport with food and feedstuffs.

UN Hazard Class: 6.1; UN Pack Group: II