2-Chlor-4-nitrotoluol

TERRESTRIAL FATE: The estimated Koc of approximately 1,391(1,SRC) indicates that 2-chloro-4-nitrotoluene would probably have slow soil mobility(2,SRC). No data are available regarding biodegradation or other chemical processes in soil(SRC).

AQUATIC FATE: If released to water, volatilization may be a significant loss process; however, the reaction may be slow (half-life of 32 hrs from a model river)(1,SRC). Based on the estimated Koc of about 1,391, 2-chloro-4-nitrotoluene may partition from the water column to sediment(SRC). Based on an estimated BCF of 173(1,SRC), 2-chloro-4-nitrotoluene may bioconcentrate in aquatic organisms(SRC). Photolysis in water may be significant; 2-chloro-4-nitrotoluene does absorb UV light >290 nm(2). However, no rate data were located. Hydrolysis is not expected to be an important fate process in aquatic systems(SRC).

ATMOSPHERIC FATE: Vapor-phase 2-chloro-4-nitrotoluene is degraded slowly in the ambient atmosphere by reaction with photochemically formed hydroxyl radicals; the half-life for this reaction in typical air can be estimated to be about 48 days(1,SRC). Photolysis in air may be significant; 2-chloro-4-nitrotoluene does absorb UV light >290 nm(2). However, no rate data were located.

Initial Medical Exam: A complete history & physical exam: ... Exam of blood, nervous system, GI system, & cardiovascular system should be stressed. Skin should be exam for evidence of chronic disorders. ... A complete blood count should be performed, including red cell count, a white cell count, a differential count of stained smear, as well as hemoglobin & hematocrit. Periodic Medical Exam: The ... /initial med exam/ should be repeated on an annual basis. Methemoglobin determinations should be performed if overexposure is suspected or signs & symptoms of toxicity occur. /Nitrotoluene/

... The onset of symptoms of methemoglobinemia is insidious and may be delayed up to 4 hours; headache is commonly the first symptom and may become quite intense as the severity of methemoglobinemia progresses. ... Cyanosis develops early in the course of intoxication, first the lips, the nose, and the ear lobes, and is usually recognized by fellow workers ... Until the methemeglobinemia concentration approaches approximately 40%, the individual usually feels well, has no complaints, and will insist that nothing is wrong. ... Over 40% ... weakness and dizziness; at up to 70% ... there may be ataxia, dyspnea on mild exertion, tachycardia, nausea, vomiting, and drowsiness. /Nitrotoluene/

Based on an estimated log Kow of 3.247(2), the bioconcentration factor (BCF) for 2-chloro-4-nitrotoluene can be estimated to be about 173 from a recommended regression-derived equation(1,SRC). This BCF value suggests that bioconcentration in aquatic organisms may be important(SRC).

The Henry's Law constant for 2-chloro-4-nitrotoluene can be estimated to be approximately 4.06X10-5 atm-cu m/mole at 25 °C using a chemical structure estimation method(2,SRC). This value of Henry's Law constant suggests that volatilization from water may be slow but possibly significant(1). Based on this value, the volatilization half-life of 2-chloro-4-nitrotoluene from a model river 1 m deep flowing 1 m/sec with a wind velocity of 3 m/sec has been estimated to be approximately 32 hrs(1,SRC).

THE COMPARATIVE TOXICITY OF 2-CHLORO-4-NITROTOLUENE (CNT) WAS INVESTIGATED IN STARLINGS, CHICKENS AND RATS. ADULT STARLINGS, 4-WK OLD NEW HAMPSHIRE CHICKENS & MALE SPRAGUE DAWLEY RATS WERE GAVAGED WITH DIFFERENT DOSES OF CNT SUSPENDED IN 2.5% CARBOXYMETHYL CELLULOSE. STARLINGS WERE FOUND TO BE EXTREMELY RESISTANT TO CNT TOXICITY, NO MORTALITY WAS OBSERVED AT THE 4000 MG/KG DOSE. THE APPROXIMATE LD50 DOSE OF CNT IN CHICKENS WAS BETWEEN 100 & 500 MG/KG. THE LD50 DOSE IN RATS WAS 2520 MG/KG. SINCE THE AMINO DERIVATIVE OF THE RELATED CMPD, 3-CHLORO-P-TOLUIDINE, IS MORE TOXIC IN STARLINGS, CHICKENS AND RATS THAN ITS NITRO DERIVATIVE, IT THEN INDICATES THAT THE BASAL ACTIVITY OF NITRO-REDUCTASE IN THESE ANIMALS IS PROBABLY ONE OF THE IMPORTANT DETERMINANTS FOR CNT TOXICITY.

THE LD50 INTRAGASTRIC DOSE WAS REDUCED FROM 2520 MG/KG TO 1790 MG/KG IN RATS PRETREATED WITH PHENOBARBITAL (75 MG/KG IP ONCE A DAY FOR 7 DAYS).

The rate constant for the vapor-phase reaction of 2-chloro-4-nitrotoluene with photochemically produced hydroxyl radicals has been estimated to be 3.35X10-13 cu cm/molecule-sec at 25 °C which corresponds to an atmospheric half-life of about 48 days at an atmospheric concn of 5X10+5 hydroxyl radicals per cu cm(1,SRC). Photolysis may be significant; 2-chloro-4-nitrotoluene does absorb UV light >290 nm(2). However, no rate data were located. Halogenated aromatics and nitro aromatics are generally resistant to hydrolysis(3); therefore, hydrolysis is not expected to be significant(SRC).