Carcinogen working with

Certain compounds found in some coal-tar and petroleum pitches are carcinogenic. Individuals working with pitches or exposed to fumes or dust should wear protective clothing to avoid skin contact. Respirators should be worn when pitch dust or fume concentrations in the air are above estabHshed limits. 

Some occupational hygiene aspects of man-made mineral fibres and new technology fibres Safe handling requirements dunng explosive, propellant and pyrotechnic manufacture Simplified calculations of blast induced injuries and damage Laboratory work with chemical carcinogens and oncogenes Rosin (colophony) a review... 

The following compounds are carcinogens and listed as such on the OSHA list. Rules to be followed when working with these substances were published in the Federal Register, Vol. 39, No. 20, January 29, 1974. 

Cadmium and its compounds are highly toxic and can be carcinogenic. Thus great care should be taken when working with this element ... 

Perchloroethylene (tetrachloroethylene) is a nonflammable solvent of low toxicity that dissolves and removes H blister and V nerve agents but does not neutralize them. NIOSH has recommended that this substance be treated as a potential human carcinogen. It does not work with G nerve agents. 

MRC (1981). Guidelines for Work with Chemical Carcinogens in Medical Research Council Establishments, Medical Research Council, London. 

Another type of biological evidence that supports a case for causation derives from experimental work with animals if the substance under consideration is carcinogenic in animals, associations seen in epidemiology studies become biologically supportable. Sometimes it is possible to conduct a study after intervening to remove the suspect substance if risk declines following such an intervention, the case for causation strengthens (recall Pott s chimney sweeps). 

Needless to say, it would be interesting to apply the same type of chemistry described in Figure 2 for the methylcarbamate esters to the synthesis of derivatives of the formamidine insecticides. However, additional work with the formamidines, particularly those related to chlordimeform, has been discouraged because of the mutagenic and carcinogenic potential of the aryla-mine metabolic products. 

HC1 is introduced at 0 C into a stirred mixture of ethanol (0.50 mol) and paraformaldehyde (15 g) until copious fumes escape from the solution. Stirring is stopped and the flask is placed in a bath at -78 C. The clear liquid is decanted from the crust of the bottom of the flask and transferred into a 1 -1 flask, which is placed in a bath at -20 C. The dissolved HC1 is then removed by evacuation (water aspirator). Since a-halocthers are suspected of being carcinogens, care should be taken when working with them. 

But, given that not all bladder cancer victims smoke, work with dyes, or operate drill presses, where could the carcinogens be coming from Chlorine-treated drinking water is a possibility. Epidemiological surveys have revealed that people who drink surface water treated with chlorine are more likely to develop bladder cancer. How much more likely Estimates are that in North America we can link roughly 4,500 cases of bladder cancer annually to chlorinated water. To put this into more understandable terms, about ten out of every thousand men who do not drink chlorinated water will develop bladder cancer if they live to be seventy, while thirteen will do so if they drink chlorinated water for thirty-five years. This, of course, assumes that those who don t drink chlorinated water are consuming water that has been purified by some other technique, an option not available to most people. 

Work with the carcinogen acetylaminofluorene found that residues of the compound in ribosomal RNA may correlate more closely with liver tumor formation than residues in DNA. Direct interactions with the mechanisms of protein synthesis, or with DNA and RNA polymerase enzymes, can also be seen as possible mechanisms. For instance, a modification of the polymerase enzymes by a carcinogen, either directly or indirectly, could lead to the erroneous replication of DNA or RNA and hence the permanent incorporation of a mutation. 

Everyone who works with organic chemicals should be aware that a number of arenamines are carcinogens. The most dangerous examples (see Figure 23-8) are known to induce human bladder cancer. These chemicals were used widely in the chemical industry (mostly in azo dye manufacture) long before they were... 

The remarkable progress achieved by Vouros et al. [120,121] in the CEC analysis of isomeric polyaromatic hydrocarbon deoxyribonucleic acid (DNA) adducts derived from in-vitro reactions of carcinogenic hydrocarbons with calf thymus DNA has been illustrated in a previous section. This work represents an... 

An area that may be used for work with carcinogens, reproductive toxins, or substances that have a high degree of acute toxicity. A designated area may be the entire laboratory, an area of a laboratory, or a device such as a loboratory hood. Detergent... 

Frequency of Medical Examination for Employees Working with Chemical Carcinogens... 

Pipetting. All liquid transfer operations are performed with mechanical pipetting aids. Figure 3 also see the Source table (6). Oral pipetting is not performed in a laboratory engaged in research work with chemical carcinogens, suspect carcinogens, or other toxic substances (7). 

Design features of facilities used for research on regulated chemical carcinogens or suspect chemicals are generally similar to those used for work with infectious microorganisms or the requirements recently promulgated for recombinant DNA research (8). 

Entrances to facilities used for research with chemical carcinogens must be controlled at points of access. Access points where chemical carcinogens or suspect chemicals are used must be posted with appropriate signs DANGER—CHEMICAL CARCINOGEN-AUTHORIZED PERSONNEL ONLY. A shower should be available within the facility to personnel working with known or suspect chemical... 

In general, four types of cabinets are used for work with research quantities of chemical carcinogens. These are the conventional fume hood a Class I biological safety cabinet a Class II (Type B) biological safety cabinet and a Class III closed glove box system (8). 

Glass surfaces have a tendency to absorb proteins, which can be particularly problematic when working with solutions at low concentrations. To avoid, or at least minimise, this difficulty, glass containers can be siliconised. The glass container is cleaned and filled with a 1 % solution of dimethyldichlorosilane solution in toluene (not benzene which is carcinogenic) and heated to 60 °C. After decanting off the solution, the glass vessel is placed in a vacuum desiccator to remove the final traces of solution, and finally rinsed with distilled water. All of these operations should be carried out in a fume hood. 

Safety Note. Because acyclic triazenes are potent biological alkylating agents, it is only prudent to assume that triazolines are also potentially toxic and carcinogenic. Efficient hoods and protective clothing should be used in working with these substances. Alkyl azides are treacherously explosive and should be treated with extreme caution. Wherever possible these compounds should only be handled as solutions. 

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