Natural – now there is a loaded word if ever there was one. My favourite use must surely be Natural American Spirit: “Taste nature. And nothing else.” Sounds enticing? Well, Natural American Spirit is actually a cigarette brand manufactured in theUnited States by the Santa Fe Natural Tobacco Company, a subsidiary of Reynolds American. The ad continued:
“You’ll never find any additives in our tobacco. What you see is what you get. Simply 100% whole-leaf natural tobacco. True authentic tobacco taste. It’s only natural.”
I have deliberately chosen an absurd example, but what I want to point out is that the meaning of natural is very problematic. There are two points I wish to raise. Firstly the line between natural and artificial is very blurred. Agriculture is a human invention;Orangesare unknown in the wild. In medicine there is a false dichotomy between natural and artificial remedies. Modern medicine does not reject nature; many modern drugs are plant components. But modern medicine doesn’t restrict itself to plant derived substances. And anyone with a knowledge of chemistry will know the line between natural and unnatural chemicals is a fuzzy one. What about a molecule that is manufactured or synthesized but is identical to a molecule that occurs in nature? Is the synthetic molecule natural because there are absolutely no detectable differences between purified natural products and their synthesised counterparts? Is its origin important? The bottom line is that there is no real clear demarcation line between something that is entirely natural and something that is completely artificial.
Over the last half century, synthetic chemicals increasingly have made our existence easier, safer and better. They help keep our homes clean, kill pests, and make agriculture more productive, enabling us to feed more people using less land. But these chemicals have not been universally welcomed. They have been accompanied by the rise of chemophobia, an irrational fear of chemicals. These prejudices are very real. The language around chemicals is unambiguously bad. Greenpeace talks about “chemicals out of control.” Hazardous, toxic and dangerous are usually the adjectives of choice. The mass media has had a particularly nefarious role in the vilification of chemicals. The media are frequently more interested in sensationalist headlines than reporting the underlying science, while environmentalists frequently resort to scare tactics. There is an absurd quest to lead a chemical-free life. Foods or products are advertised as “chemical free.” However, everything is made of chemicals and nothing can be ‘chemical free’. There are no alternatives to chemicals, just choices about which chemicals to use and how they are manufactured. I love this quote by research chemist Derek Lohmann at the website of sense about science:
“If someone came into your house and offered you a cocktail of butanol, iso amyl alcohol, hexanol, phenyl ethanol, tannin, benzyl alcohol, caffeine, geraniol, quercetin, 3-galloyl epicatchin, 3-galloyl epigallocatchin and inorganic salts, would you take it? It sounds pretty ghastly. If instead you were offered a cup of tea, you would probably take it. Tea is a complex mixture containing the above chemicals in concentrations that vary depending on where it is grown.”
But for the sake let’s assume that we can agree that some things are natural and some are not. What does that tell us? Nothing. This is well-known intellectual fallacy known as the appeal to nature. It goes like this:
N is natural. Therefore, N is right or good. U is unnatural. Therefore, U is wrong or bad. As Julian Baggini has pointed out there is no factual reason to suppose that what is natural is good (or at least better) and what is unnatural is bad (or at least worse). Alas, being natural is no guarantee that a substance is safe. There are many poisons in nature, including hemlock, cyanide, arsenic, and animal and insect venoms. The carcinogens in cigarettes that cause cancer are natural components of tobacco. Henna tattoos can cause allergic reactions. Untreated water can kill, and rotting fruit contains some toxins that can make people very ill. In the late 1990s Bruce Ames, head of the Department of Molecular and Cell Biology at theUniversityofCalifornia,Berkeleyproved that cabbage has forty-nine natural pesticides in it, more than half of which are carcinogens. Nature has not been designed for our benefit. What’s more poisons are a typical evolutionary strategy used by flora and fauna.
Food is an area where these questions of natural and artificial are often debated. I tend to be a bit sceptical about organic. A 2010 review, in the American Journal of Clinical Nutrition, which did a meta-study of the last 50 years of research, showed that there were no significant differences in nutritional value and no health benefits from eating organic food. And organic food has a significant downside that was pointed out byAmes:
“The effort to eliminate synthetic pesticides … will make fruits and vegetables more expensive, decrease consumption, and thus increase cancer rates.”
Then we come to the raw food movement. I prefer the tem crudivore, but you have to be careful how you pronounce this word as you may unwittingly imply that they eat crud. Raw foods as a dietary health treatment was first developed in Switzerlandby medical doctor Maximilian Bircher-Benner. During a bout of illness he couldn’t eat any cooked food, so he began eating apples and nothing else every day. After he got over the jaundice he conducted experiments into the effects on human health of raw vegetables. In November 1897, he opened a sanatorium in Zurichcalled Vital Force. Bircher-Benner also invented muesli which was a way of encouraging people to eat raw food, as the main ingredient was raw apple, rather than the cereal or yoghurt of today. Naturally this movement has attracted its fair share of Hollywoodtypes such as Demi Moore, Woody Harrelson Ben Vereen (he played Chicken George in Roots. some of the claims of this movement are hilarious. It is especially popular in the UK, Germanyand of course California. Restaurants catering to a raw food diet have opened in large cities, and numerous all-raw cookbooks have been published. The proponents of raw food argue that uncooked food is “living” and that pasteurization “kills” food. There is little scientific evidence to back up their claims; there are only minimal differences in the nutritional value of food that is raw versus lightly or even moderately cooked. Even if they were right about the evidence, I would still disagree with crudivores. For me cooking is one our greatest human inventions.
For Prince Charles the price of prosperity has been “a progressive loss of harmony with the flow and rhythm of the natural world”. I have tried to show that this mythical world never existed. As this New Yorker cartoon showed, we may have had cleaner air purer water, exercised more and eaten lots of free-range stuff but most people didn’t live past 30. The invention of synthetic chemicals has been on the whole positive for humanity. They are monuments to mankind’s progress. I am not saying that chemicals cannot be dangerous.Bhopal and asbestos are two relevant examples. But we need to take a more mature attitude – we need to forget about this mythical world without chemicals.
Labelling a chemical toxic or a contaminant is meaningless. It always depends on the size of the dose. Moreover, chemicals do not have the same effects on everybody; people can react differently to the same dose. We are now able to detect chemicals in parts per billion. But this does not mean that these miniscule doses are dangerous. This is why the safe exposure levels that are published for chemicals tend to be well below the levels likely to cause harm.
Since the 1960s we have been hearing stories of how the use of synthetic chemicals, was going to cause a massive cancer epidemic. I don’t see evidence of this being caused by synthetic chemicals. Outside the workplace, very few cases of cancer are believed to be caused by exposure to chemicals in the environment. The more relevant fact is lifestyle and the fact that we are living much longer. Establishing correlation is extremely tricky. Just because a chemical was present when an effect occurred does not demonstrate causation. Cancer clusters may just prove to be random variations.
We cannot avoid trade-offs. Even where chemicals are potentially harmful, we have to balance the potential risks of any chemical against the benefits they bring. For example, when insects attack African farms, threatening rural survival, it may be better if farmers spray pesticide even if this means they might inhale some of it themselves. In the nineteenth century there was anxiety about using powdered chlorine bleach to disinfect water it reduced the bacteria count spectacularly and helped to eradicate typhoid.
The blanket demonization of the chemical industry is illogical and dangerous. We are going to need chemists who can find new ways of making fertilisers or plastics. We face new problems and we will need a new greener chemical industry to help us meet the challenges of the twenty-first century.