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Overview: Aflaloxins are highly toxic, cancer-eausing chemica1s produced by fungi belonging to the genus Aspergillus. Aspergillus jlavus is the most important causal agent of crop aflatoxin contamination. We developed a strategy for preventing aflatoxin con· tamination based on the use of naturaUy occurring isolates of A jlaUlJS that Jack aflatoxinproducing ability (atoxigenic strains). The atoxigenic strains displace anatoxin producers during crop development and infection and thereby reduce contamination. Although gig. nmeant single-seasoo effects are achieved, the greatest potential is for long.term and area-wide influences. This chapter discusses the history of development and commercialization of atoxigenic strains. Aflatoxin ContaminationAflatoxins are highly toxic, cancer-causing chemicals produced by several fungal species within Aspergmus section F1avi. Presence of aflatoxins in human foods causes acute and chronic health effects (aflatoxicoses), ranging from immunesystem suppression, grolAlth retardation and cancer to death from acute poisoning (Wild and Turner, 2002). In developed countries, stringent government regulations limit the use of aflatoxin-contaminated crops in foods and feeds, and, as a result, commodities with aflatoxin content exceeding the maximum permissible level have significantly diminished cash value. In crops intended for human consumption, maximum permitted aflatoxin levels range from 2 ppb in the European Union to 20 ppb in the USA. As aflatoxins are readily transferred from animal feed to milk, similar stringent regulations are imposed on feed intended for dairies (Wu, 2004). The action level for aflatoxins in US milk is 0.5 ppb.

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Abstract:The interaction of water with cellulose and its influence on the nuclear spin dynamics in Gossypium barbadense (Pima) C resonances from only the crystalline or the amorphous domains or from only the surface of the cellulose). However, spatial localization of the combined Goldman-Shen-13 C CP/MAS experiment using both short mixing and contact times yields a spectrum consistent with predominantly the I β polymorph of cellulose. Longer mixing times and the same, short contact time yield a spectrum that is indicative of an increased I α polymorph content in the crystallite interiors relative to the smaller values found with short mixing times.

Bales of cotton were classified by the International Maritime Organization (IMO) code regulations as a flammable solid (Class 4.1), which required hazardous goods papers to accompany waterborne shipments. Various scientific investigations were conducted to evaluate the flammability hazard of bales of cotton to determine if this hazardous designation was valid. Cigarette (NFPA 261/ ASTM E1352), match (NFPA 705) and open flame (CA TB 129) tests were conducted; the potential for self-heating and spontaneous combustion was evaluated; and the potential of cotton bales sustaining smouldering combustion in their interiors at various compression densities was studied. These studies showed that bales of cotton should not be required to have the hazardous designation, 'flammable solid', and led to the IMO and the US Department of Transportation (DOT) removing the designation for baled cotton [compressed to a density of 360 kg=m 3 ð22:4 lb=ft 3 Þ or greater; meets ISO 8115], with effect from 1 January