From the
1964 Watchtower
"Not only is blood being used in connection with modern medical practices, but it is reported that blood is now being used in a variety of products, such as adhesives for making plywood, particle board, hardboard, bottle crowns, furniture and musical instruments. Blood is also being used in polymerization of rubber compounds, insecticidal binder, settling compound for industrial waste treatment, clear water purification (paper industry), uranium purification, foaming agent for lightweight cellular concrete, fire foaming agent, wine clarifying agent, paper coatings and binders, paper flocculants and sizes, replacement of casein in latex emulsions, emulsified asphalt, cork composition, photoengraving platemaking solutions, leather-finishing operations, water-resistant binder of pigments for print dyeing on cotton cloth, fertilizers, animal foods, and amino acid production, such as histidine and histamine, for example. Perhaps additional uses of blood will come to light in the future. In the world the uses of blood are numerous and none of these is in accord with the Biblical method of handling blood, which is to be spilled on the ground. However, the Christian is not responsible for the worldly misuse of blood, what other people do with it, and he cannot spend all his time undertaking detailed research regarding the various misuses of blood in the world of mankind, especially when it comes to nonedible products. If he did so, he would have less time left for preaching the good news of God’s kingdom. To some persons, it may be a hard decision to make as to where one should be employed. It resolves itself to a matter of conscience."