Source Year: 1998

Prick test studies of raw materials and products of commercial natural rubber latex and highly deproteinised natural rubber latex showed different threshold levels of residual extractable protein. Allergenic activity must also take account of the nature of the allergenic proteins; the problem cannot be referred solely to the amount of extractable protein. The threshold level for NRL products is currently 50-100 ng/g, a level impossible to attain by leaching out the protein content. The proteolytic effect of enzymes has a considerable impact. In HDPNRL products the threshold level is relaxed by a factor of 600, taking the threshold to 30-40 ug/g and the allergen free requirement is easily attained. One way of eliminating latex allergy would be to add a purpose-designed proteolytic step to the NRL product manufacturing process. It is recommended that this or a similar process be introduced to decompose the protein contained in NRL.