ABC of Safety in the Biological Sciences



CONGO RED (Colour Index No. 22120 (C32H22N6O6S2Na2)

Cotton red B, cotton red C, direct red C, direct red R, direct red Y, congo, atlantic congo red, atul congo red, benzo congo red, diacotton congo red, trisulfon congo red, vondacel red CL, cotton red L.
Brownish­red powder. Disazo group of dyes.
Heating produces toxic fumes of nitrogen and sulphur.
This dye is highly toxic and a mutagen. Staff who are pregnant should not handle this powder. It is an eye, skin and mucous membrane irritant and can be absorbed through the skin and mucous membranes into the body. Repeated or prolonged skin contact may cause dermatitis. Prolonged eye exposure can cause conjunctivitis.
Use a fume hood.
Highly toxic.
Avoid inhalation or ingestion of the powder.
Mutagen, do not allow staff who are pregnant to handle this powder.
Keep away from heat.
Avoid skin or eye contact.
Wash hands thoroughly after handling.
Use a fume hood to keep the level of exposure as low as possible. Wear protective clothing. A long sleeved laboratory coat or gown, rubber gloves, safety goggles and a face mask as a minimum standard.
Skin ­ remove contaminated clothing and immediately wash the affected area with soap or mild detergent and large amounts of water until all evidence of the dye has been removed (approximately 15 minutes). If irritation persists or dermatitis develops seek medical attention. Wash contaminated clothing before re­use.
Eyes ­ immediately wash the affected eye with large amounts of water until all evidence of the dye has been removed (approximately 15 minutes). If irritation or pain persist seek immediate medical attention.
Inhalation ­ remove from the area of exposure to fresh air. If breathing has ceased apply artificial respiration. Give oxygen if necessary. Keep warm and allow to rest. Seek immediate medical attention.
Ingestion ­ if the victim is conscious wash the mouth thoroughly with water and give a large amount of water to drink. Seek immediate medical attention.
Store in a cool, dry atmosphere away from heat.
Leather gloves, heavy face shield and laboratory coat. Work from behind a barricade (body shield or wall). Avoid unnecessary heat, friction or impact.
Absorb the liquid with paper or vermiculite. If it is a solid, dampen then brush on to paper with great care. Place in a plastic bag and remove outside for burning.
Sponge up with water, followed by decontamination with 10% ammonium ceric nitrate solution. 'Kill', by adding to a greater stoichiometric amount of ammonium ceric nitrate solution with agitation sufficient to provide suspension of all solids. Cool the reaction. The organic azides and heavy metal azides are explosive. Alkali and alkaline earth azides are not considered explosives under normal laboratory conditions. Keep the stock of azides very low. Stamp the date of receipt upon the package.


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