Let me just address the first comment you made because of an interesting statement the interpreter made. You asked...when looking at my biography and the things that I do, because I give a lecture on the chemistry of love, and the interpreter said, “I thought I heard 'love', but it couldn't be that.” Well, it could, because I do do that.
The idea is that the world, of course, functions on chemicals, both natural and synthetic, and I try to emphasize that and explain it, including the fact that there are certain substances that are responsible for our falling in love. One that has been looked at is a chemical called phenylethylamine, which has been found in chocolates.
The press has made a big deal about that--chocolates being the classic gift of lovers on Valentine's Day--because you're saying, here, have some phenylethylamine and fall in love, hopefully, with the donor. It's a charming story but it's really chemical nonsense, because the phenylethylamine never goes through the blood-brain barrier, never goes to the brain. As we know, chocolates go directly to the hips without getting into the brain.
Those kinds of chemical subtleties are important, which addresses your next question about the mixture of chemicals. I don't have any answer to that and I don't think anyone has any answer to that because it's such an unbelievably complex mixture.
We can't possibly measure all the interactions. There certainly are some interactions that we know. We know, for example, that if you have iron and vitamin C together in your diet, the vitamin C enhances the absorption of iron. I mean, these kinds of things have been done. We know, for example, that if you take certain medications, you can't take them with grapefruit juice because it changes the blood chemistry, changes the level.
But these are unique interactions that have been measured. It just isn't possible to globally measure every possible interaction. What we do is we take a look at total exposure, doses, and the underlying chemistry, and based upon the knowledge that we have accumulated, we try to come to some sort of decision. It cannot be certain.
You also asked the question about the ozone layer. Just to give you a little bit of a history to that, the reason that the chlorofluorocarbons were introduced in the 1930s was because in those days refrigeration systems worked on ammonia or hydrogen sulphide. These are terribly toxic substances--terribly. There were all kinds of ammonia leaks. You may remember just a couple of years ago there was still some old ammonia system used in a hockey rink somewhere in Alberta and the ammonia leaked out and a number of people were very severely hurt.
There was a need to find a new chemical to replace the ammonia. The chlorofluorocarbons were great because they were chemically very unreactive. You could put them into a refrigerator and compress them, and when they expanded, they sucked the heat out of the fridge. Everyone thought that this was great.
Nobody at that time could ever have imagined that these chemicals could eventually have an impact on the ozone layer in the stratosphere. And how could they? Why would anyone have ever thought of that? There wasn't any knowledge about ozone destruction. It just wouldn't have come up. You had a problem that you wanted to solve, which was the problem of refrigeration. It was a tremendous breakthrough. It saved thousands of lives by introducing the freons instead of ammonia.
Then eventually we found that there was a problem with the ozone layer. Now we address that problem because we find that not all freons fall into the same category. It depends on exactly how many chlorines, how many fluorines we have in the molecule, and exactly how they are arranged.
Well, now we have freons that don't have an impact on the ozone layer. Will they have an impact on something else that we find out 30 years from now? Nobody really knows, but we have a pretty good base on which to make judgments, because since the 1930s we've accumulated a lot of toxicological information and I would say that the chance is that the freons we're introducing now have a minimal chance of having any type of untoward effect. But it always comes down to making the decision.
I'm not a proponent for industry. I don't care if industry does well or not. I'm an academic--all I'm interested in is the scientific method and good science--but I don't think that industry is bent on unleashing dangerous substances into the environment, because in the end it doesn't do them good either. What does them good is producing good products that the public will appreciate and benefit from with minimal hazard. But you can't always predict that a hazard will be minimal.
It comes down to making decisions, but the decisions should be made by people who have expertise in chemistry, toxicology, and physiology.