Is benzidine a toxic chemical?
No information is available on the acute (short-term) effects of benzidine in humans by inhalation exposure but benzidine is considered to be very acutely toxic to humans by ingestion. Chronic (long-term) exposure to benzidine in humans may result in injury to the bladder.
Why is benzidine a carcinogen?
Studies on Mechanisms of Carcinogenesis Benzidine is metabolized by cytochrome P450 enzymes (via N-oxidation) to form electrophilic compounds that can bind cova- lently to DNA (Choudhary 1996).
What is a benzidine reagent?
Benzidine is a grayish-red, yellowish or white colored, very toxic, crystalline aromatic amine that darkens when exposed to air and light. Benzidine has been widely used for the detection of blood and as a reagent in the manufacture of dyes.
What is the Colour of benzidine?
|Appearance||Grayish-yellow, reddish-gray, or white crystalline powder|
|Melting point||122 to 125 °C (252 to 257 °F; 395 to 398 K)|
|Boiling point||400 °C (752 °F; 673 K)|
What is benzidine test for blood?
Medical Definition of benzidine test : a sensitive test for the presence of blood (as in urine or feces) based on the production of a blue color upon contact with a solution of benzidine, hydrogen peroxide, and glacial acetic acid.
What is the limitations of benzidine test?
Benzidine-based tests (e.g., Hematest) have been virtually eliminated from use because of their excessive sensitivity, which results in a high frequency of false-positive reactions, as well as the carcinogenicity of the reagent.
What is benzidine test used for?
The benzidine test is most commonly used for the detection of blood in the feces, and was therefore singled out for investigation.
How is benzidine test done?
of glacial acetic acid in a clean test-tube, thus obtaining a 0-5 per cent, solution of benzidine hydrochloride. Then either the examining finger of a rectal glove or a clean orange-stick dipped in a faecal specimen is smeared on white filter-paper, and a little of the benzidine solution is poured over the smear.
What are the acute effects of benzidine in humans?
Acute Effects: No information is available on the acute effects of benzidine in humans via inhalation exposure. Benzidine is considered to be very acutely toxic to humans by ingestion. Symptoms of acute ingestion exposure include cyanosis, headache, mental confusion, nausea, and vertigo.
How are people exposed to benzidine-based dyes?
Inhalation and accidental ingestion are the main ways people can be exposed to benzidine-based dyes in the United States. As benzidine-based dyes were removed from both industrial and consumer markets and replaced with other types of dyes, the potential for exposure has declined.
Is there any benzidine in the United States?
Benzidine is no longer produced in the United States, although benzidine-based dyes may be imported into this country. No information is available on the acute (short-term) effects of benzidine in humans by inhalation exposure but benzidine is considered to be very acutely toxic to humans by ingestion.
What was benzidine used for in the past?
In the past, large amounts of benzidine were used to produce dyes for cloth, paper, and leather. It was also used in clinical laboratories for detecting blood, as a rubber-compounding agent, and in the manufacture of plastic films. However, benzidine has not been sold in the United States since the mid-1970s,…