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March 26, 1970 The Possibility of Passive Protection from Non-speciflc Toxins In order ~o examine the effects of inhibitora on enzymes, biochemists normally rigorously purif7 the enzyme so that components of the crude preparation do no~ in~erfere by reacting with the inhibitor. This implies the= =he ocher eons=i=uen~s of =he cr~de preparation can afford a degree of tprotectlon~ to the enzyme. We have recently come across an example of this 'protection' during a study of the effect of an aqueous solution of smoke vapour phase (VP) on salivary and hog pancreatic =-anylases (see accompanying paper). it was found that V~ had a pronounced inhibitory effect on pure hog pancreatic a-amylase but not on crude salivary u-amylase. If the hog pancreatic enzyme was added to saliva, It too was 'protected' from the inhibitory effect of VP. Also, as the salivary enzyme was progressively purified i~ became more sensitive to VP. It appears, therefore, ~ha~ some salivary constituents are acting as sponges and are absorbing or reacting with VP inhibitors before they can reach ~he enzyme. ~hile carrying out ~his work our attention was drawn to an experimen~ by Dr. Hans Barkemeyer, showing ~ha~ B(a)P is absorbed and tlgh~ly bound by ere albumin. It seemed likely tha~, if ere alSumin could bind B(a~P, serum albumin should also. Dr. Barkemeyer kindly told us how the protein hydrocarbon reaction could be done and we have ~ested the reaction of bovine serum albumin (~$A) wi~h B(a)P-C1~. Under our conditions a~ least ~SX of the ~(a)P is absorbed by ~he BSA and cannot be extracted w~th cyclohexane. This too, may be an example of pro~ectlou: serum albumin should react with any B(a)P entering the blood stream before it has the opportunit7 to react vlth more vi~al components of the organism. Before considering the albumln-B(a)P complex as a pro~ectlve factor important to consider the fate of ~he complex in an animal ~o find whether the ~(a)P is excreted, or whether the albumin merely acts as a carrier and drops the hydrocarbon at some o~her site. The following set of experiments should answer these questions. 1. prepare rabbit serum albumin B(a)P-CI~ complex. 2, purify and ~,Jec~ into an animal of the same s~ra~n. sacrifice and examine various organs for C1~ ~o see if deposition of B(a)P has occurred, On the basis of these ideas a generalised hypothesis can be formulate~. BAT Industries document for Province of British Columbia 9 November 2000 BAT INDUSTRIES 00290383

~en non-specific toxins, i.e. those having no specific targets, enter a living system,they will react with whatever suitable compounds are present in the highest concentration or wit], those which offer the most .reactive sites. In the case of saliva, inhlbltore in the vapour phase react with the 'mucoids or other salivar~ components which are present in relatively high concentration and have no clearly defined metabolic roles thus shielding a-amylase which has a well defined catalytic function and is present in lower concentration. It is felt that this passive protection is of considerable importance and presents a new framework for eonsldering the effects of smoke on living systems. It will also help to single out smoke components against which the body has no protection so that special efforts may he made to eliminate them or reduce their concentration in tobacco smoke. BAT Industries document for Province of British Columbia 9 November 2000 BAT INDUSTRIES 00290384