Benzoyl chloride appears as a colorless fuming liquid with a pungent odor. Flash point 162°F. Lachrymator, irritating to skin and eyes. Corrosive to metals and tissue. Density 10.2 lb / gal. Used in medicine and in the manufacture of other chemicals.
When 14C-labeled benzoyl chloride was applied to the dorsal musculature of a male Wistar rat through a small incision, only traces of radioactivity were found in the urine and feces. At 3 days post-application, most of the radioactivity remained at the site of application. The benzoyl chloride appeared to react mostly by acylation of nucleophilic groups and very little hydrolyzed to benzoic acid.
/After/ a single oral dose of labelled benzoyl chloride (9-13 mg/kg bw) administered to rats,/ ... over 90% of the metabolites in the urine were identified as benzoic acid and hippuric acid.
IDENTIFICATION AND USE: Benzoyl chloride is a transparent, colorless liquid, or slightly brown liquid with a penetrating odor. It is used for for acylation (introduction of benzoyl group into alcohols, phenols, and amines). It is also used in the manufacture of benzoyl peroxide and of dye intermediates, and in organic analysis for making benzoyl derivates for identification purposes. HUMAN STUDIES: Benzoyl chloride has a corrosive effects on the skin, eyes, and mucous membranes by inhalation. It can cause cough, labored breathing, nausea, and sore throat after inhalation. Redness and irritant pain on contact with the eye and skin. Burning sensation, nausea and vomiting upon ingestion. Three cases of lung cancer have been reported among workers engaged in production of benzoyl chloride. ANIMAL STUDIES: Benzoyl chloride was found to be corrosive to rabbit eyes. In male rats exposed to benzoyl chloride by inhalation signs of intoxication included inactivity, piloerection, unkempt fur, and difficulties in breathing up to 19 days post exposure in all rats. Rats that died during the test showed dark red colored lungs always with emphysema, some rats showed lung edema. Rats that survived showed no pathologic findings up to 0.708 mg/L. At higher concentrations lungs showed emphysema and were mottled, some showed enlarged adrenals. Benzoyl chloride was found to induce tumors in mice following inhalation exposure. Benzoyl chloride was positive in the bacterial gene mutation assay, preincubation method in Escherichia coli WP2uvrA/pKM101 with and without activation at concentrations up to 1000 ug/plate. Benzoyl chloride was not mutagenic in Salmonella typhimurium strains His g46, His c3076, His d3052, TA1535, TA1536, TA1537, TA98 or TA100, nor in Escherichia coli strains Wp2 and Wp2 uvra- with or without metabolic activation. Benzoyl chloride was weakly mutagenic to Salmonella strain TA98 in the absence of metabolic activation. ECOTOXICITY STUDIES: In a 96 hr lethality study with the Zebrafish (Brachydanio rerio) no toxicity was found at 7.5 mg/L and all the fish died at 10 mg/L. Benzoyl chloride reacted with water to give benzoic acid and hydrogen chloride, causing a decrease in pH to 5.2 in freshwater and 7.2 in salt water. However, the biological oxygen demand of the benzoic acid was a far more serious effect. In the saltwater test of grass shrimp this was believed to be the major cause of mortality since dissolved oxygen levels plunged below 1 mg/L in direct correspondence to initial benzoyl chloride concentration.
Evaluation: There is limited evidence in humans for the carcinogenicity of ... benzoyl chloride. ... There is inadequate evidence in experimental animals for the carcinogenicity of benzoyl chloride. Overall evaluation: Combined exposures to alpha-chlorinated toluenes and benzoyl chloride are probably carcinogenic to humans (Group 2A). /alpha-Chlorinated toluenes & benzoyl chloride/
The absorption and excretion of (14)C-benzoyl chloride was studied in male and female Holtzman albino rats. Following single oral doses of 9 to 13 mg/kg, benzoyl chloride was rapidly absorbed from the gastrointestinal tract and efficiently eliminated in the urine (90%) and feces (2%) within 48 hours. ... After 72 hours, the total radiocarbon residue in tissues was approximately 1.5% of the dose; fat liver, and kidneys contained the highest residue levels.
Only a small amount of radioactivity was found in the urine and the feces after application of 10 uL labeled benzoyl chloride through a small incision on the dorsal musculature of male Wistar rats, measured over a period of 15 days. Organ distribution of radioactivity 3 days after application of 10 uL labeled benzoyl chloride through a small incision on the dorsal musculature of male Wistar rats: brain< heart< kidneys< lungs< spleen< skin/muscle.