Future Prospects of Biotechnology for Odor Control

Abstract

The world’s populations are simultaneously growing and migrating to the cities. This produces rapid expansion of urban areas into the surrounding countryside where they encroach on land dedicated to waste treatment, industry, andagriculture.Farmersare seeking increasedefficiency throughmeasures that grow animals in dense concentrations nearer the point of consumption. Rapid development of newmaterials and new industries creates a host of exotic chemical discharges. Odors form the burgeoning fast food industry are a special problem – coffee and fried chicken may smell great when you are ready to eat, but the continuous smell of roasting beans or stale grease becomes offensive. All of these trendsmean that populations are more often living close to odorous facilities, and it means that odor control is an ever more pressing air quality problem. Cries from the farmers and treatment plant operators of “We were here first!” will have little effect. With respect toodors, ugliness is entirely in thenoseof thebeholder.Wehave evolved to recognize some compounds as associated with danger: the smell of human waste is offensive because those individuals who avoided contact with it were less likely to die of disease, and the smell of spoiled food prompts us to avoid eating meals that could threaten food poisoning. The perception that an odor is foul is the body’s way of telling the brain that it is best to go elsewhere. In modern society, we frequently encounter odors that no longer represent a health risk – it is not dangerous to be downwind of a dairy. But while the nose may not provide accurate warning of the presence or absence of a health risk in modern society, the evidence suggests that unpleasant odors can cause adverse physiological and neurogenic responses. The study by Schiffman et al. (2000) found that the most frequently reported health complaints related to odors include eye, nose, and throat irritation, headache, nausea, diarrhea, hoarseness, sore throat, cough, chest tightness, nasal congestion, palpitations, shortness of breath, stress, drowsiness, and alterations in mood. Certainly, unpleasant odors can cause human nuisance and physical discomfort. Noxious and foul odors also have economic consequences. Foul odors can reduce property values in affected neighborhoods from 15 to as much as 90% (Kleemeier et al. 2002;Weida andHatz 2002;Anstine 2003). Theoffensive odors