The obvious advantages of the use of pesticides is hampered by the risks they can pose to humans and the environment. Sound evaluations of pesticides and easy access to these evaluations will help nations to choose those pesticides that will create the fewest risks. There are now about 50 international organizations, approximately 15 of them within the United Nations system, with some engaging in pesticide evaluations and regulations. The present survey of 72 pesticides of major global economic importance reveals that there is a lack of data for many of these pesticides, whereas others might be subjected to duplicate work and even confusing regulations. More joint programs and intensified information on ongoing activities, both internationally and nationally, should be encouraged. WHO has classified 71 of the 72 pesticides according to hazard for people handling them. International cancer risk classifications exist for three of them (IARC 1987), and U.S. EPA cancer classifications for 18. The availability of pesticides impacts humans and the environment. FAO/WHO has recommended different degrees of restrictions on the availability of 16 of the pesticides. According to United Nation Headquarters (1987), 20 of the 72 pesticides have been banned, withdrawn, or severely restricted in one or more countries. AIDs have been suggested for 31 of the 72 pesticides by FAO/WHO. Nationally, U.S. EPA has established reference doses for 44 of the pesticides. MRLs have been set by FAO and WHO for 31 of the pesticides in food and by WHO for 12 in drinking water. Nationally, there are great variations in tolerance levels as well as in rules for setting these tolerances, including group tolerances for related pesticides

The transverse water proton relaxation in three widely differing types of sample, native lysozyme solutions, skimmed milk and apple, has been analysed. The relaxation times show characteristic variations with CPMG pulse spacing and morphology which can be interpreted in terms of chemical exchange and molecular diffusion without recourse to popular concepts such as various amounts and types of 'bound' water. Our suggest that transverse water proton relaxation might be used as a sensitive probe of changes in water distribution during cellular growth and differentiation, freeze-thawing and dehydration-rehydration in food systems.