Malodorants agents

Munition grade agents typically consist of at least one malodorant agent (10-90%) and an odor intensifier (0.5-5%) dissolved in a liquid carrier. Solvents include volatile hydrocarbons, plant/vegetable oils, and water. Solvents typically pose minimal toxic hazards themselves. Compositions are typically colorless to yellow liquids. As the agent ages and decomposes it may discolor and become brown. 

Liquid Fabric Softeners. The principal functions of fabric softeners are to minimize the problem of static electricity and to keep fabrics soft (see Antistatic agents). In these laundry additives, the fragrance must reinforce the sense of softness that is the desired result of their use. Most fabric softeners have a pH of about 3.5, which limits the materials that can be used in the fragrances. For example, acetals cannot be used because they break down and cause malodor problems in addition, there is the likelihood of discoloration from Schiff bases, oakmoss extracts, and some specialty chemicals. Testing of fragrance materials in product bases should take place under accelerated aging conditions (eg, 40°C in plastic bottles) to check for odor stabiUty and discoloration. 

The addition of therapeutic or cosmetic agents to dentifrices has paralleled advances in knowledge about factors affecting the human dentition. Agents added to dentifrices can act directly on the host tooth stmcture or on specific oral accumulations, for example, the principal action of fluoride is on the tooth enamel. The primary action of an abrasive, however, is on an accumulated stained pellicle. Oral accumulations of interest to preventive dentistry are dental pellicles, dental plaque, dental calculus (tartar), microbial populations responsible for oral malodor, and oral debris (food residues, leukocytes, etc). Plaque is most important because of its potential to do harm. 

Malodorants are primarily an inhalation hazard. Aerosols and vapors are extremely foul smelling at low concentrations but are otherwise relatively nontoxic. However, exposure to bulk liquid or solid agents may be hazardous through skin absorption, ingestion, and introduction through abraded skin (e.g., breaks in the skin or penetration of skin by debris). 

Malodorants generally do not react with water or are very slowly decomposed by water. Most of these agents are incompatible with strong oxidizers. Solvents used to disperse agents may also be incompatible with strong oxidizers. 

Malodorants are primarily an inhalation hazard however, at elevated vapor/aerosol concentrations or in contact with bulk material, agents may also pose a dermal hazard. 

Some malodorants are insoluble in water and difficult to remove with soap and water. In such situations, an aqueous solution of mild oxidants may be effective in destroying the odorous ingredients of the agent. Published examples include... 

Deodorant soaps add fragrances that are partially substantive to the skin and that mask body odors, and antimicrobial agents. The antimicrobials, such as Tritfocarban , are deposited on the skin and inhibit bacterial growth and assodated malodors. 

Anhydrous NaC102 crystallizes out of solution above room temperature and serves as an oxidizing agent toward malodorous and toxic organic compounds. 

Mucolytic Agents. Acetylcysteine, which is frequently used as a bronchial mucolytic agent in patients with cystic fibrosis, can be used topically in a weakened concentration for ophthalmic use. It is malodorous and may sting on instillation however, this drug is fairly effective in disrupting mucous strands that are often present in patients with aqueous deficiency dry eye. It is not commercially available in an ophthalmic formulation it must be compounded by a pharmacist. 

Mouthwashes and dentifrices can serve an esthetic function by reducing halitosis. They can accomplish this by masking malodors, acting as antimicrobial agents, or both. There are no ADA-accepted products to reduce halitosis at this time. 

Contamination of persons with malodorous substances, such as mercaptans and amines, has been proposed as a means to deter less motivated rioters based on psychological and physiological effects such as olfactory repulsion and nausea (Whitten et al., 1970). They can be delivered by frangible missile, and addition of a thickening agent will prolong adhesiveness. 

Whitten, B., Wagman, W., Saffer, R., and Cohen, I., Malodorous substances as riot control and training agents, Edgewood Arsenal Technical Report Series Number 4370, Department of the Army, Edgewood Arsenal, MD, 1970. 

WO 01/23516 04/2001 Foley et al.l Procter Gamble Compositions that are particularly effective at masking malodors or odor suppression. Complexing agents (cyclodextrins) that have an internal cavity, forming complexes that incorporate the malodor... 

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