The Pharmaceutical Journal
Vol 268 No 7191 p4448
30 March 2002

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Deadly traffic [more]
Vital cation [more]
Strange creatures [more]
The middle way [more]

Deadly traffic

A massive study carried out by the American Cancer Society, involving some 1.2 million adults since 1982, has demonstrated that people exposed for long periods to fine particulate air pollution have a materially increased risk of dying from cardiopulmonary, and particularly lung cancer, causes. The survey, reported in the Journal of the American Medical Association for 6 March, involved the collection of data, including age, sex, race, weight, height, education, marital status, diet, consumption of alcohol and tobacco, and occupational exposure.

For half a million individuals living in metropolitan areas of the United States, an association was established between ambient fine particulate matter in the atmosphere and an increased risk of death of 4 per cent from all causes, 6 per cent from general lung diseases and 8 per cent from lung cancer. Particles smaller than 2.5µm in diameter, which are known to lodge deep within the lungs, are those most liable to induce lethal disease.

The exposure limit set by the Environmental Protection Agency in the US in 1997 was 15µg of fine particles per cubic metre, although it has been reported that typical concentrations of 16µg/m³ in New York and 20µg/m³ in Los Angeles occur. Monitoring of the level in Marylebone Road in London has shown an average of 32µg/m³. In developing countries there is a more severe problem, where the most heavily polluted cities, notably Delhi and Beijing, have shown fine particulate concentrations exceeding 300µg/m³. Although cigarette smoking accounts for the most impressive mortality attributable to fine particles, city traffic, particularly vehicles propelled by diesel fuels, is a noteworthy source of lethal contamination.

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Vital cation

The important role of the calcium ion in cellular function throughout the body is the subject of a paper by Malcolm East of the University of Southampton in Chemistry in Britain for March. He approaches the phenomenon from the standpoint of malignant hyperthermia, a lethal condition resulting from the explosive release of calcium from stores in muscles, which in turn generates large amounts of heat, capable of raising body temperature from 37 to 47C.

Muscular contraction follows the release of internal calcium stores whenever a nervous stimulus prompts it. In malignant hyperthermia the muscles remain rigid, but in normal circumstances they relax as energy provided by adenosine triphosphate pumps the calcium back into storage .

Calcium ions indeed play a major role in the control of all body cells by carrying intracellular messages. High calcium concentrations intracellularly trigger apoptosis, bringing about the death of cells when appropriate.

The signalling function of calcium is therefore complex, since it is involved in so many aspects of cellular function. If the individual pathways it affects could be selectively influenced by drug treatment, many therapeutic interventions might be made possible and diseases ranging from cancers, diabetes and cardiovascular conditions in the developed world to malaria and parasitic diseases in developing countries might be tackled with success.

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Strange creatures

We tend to think that imaginary, fantastic plants and animals have had no place in serious works of natural history. According to Sandra Knapp, a botanist from the Natural History Museum, writing in Nature for 31 January, this is not true. Carolus Linnaeus himself, in the earlier editions of his 'Systema naturae', first published in 1735, in addition to the three kingdoms of nature, included a fourth which he called Paradoxa, comprising fabulous monsters. Linnaeus deleted this class from the book in its sixth edition of 1748, but reassigned some of the old names to real living organisms, such as the bird Pelecanus, the coelenterate Hydra and the reptile Draco. Satyrus became applied to a monkey. In the 20th century an author and poet, Jorge Luis Borges, revived a category of imaginary beings.

However, it has been shown that the reality of zoological creatures is much richer than can be achieved with imagination.Evolution and natural selection, the forces that shape the diversity of nature, are far more innovative than even the most fertile imagination, Knapp points out. Yet in describing diversity poets and scientists draw closer together. "Both poets and scientists choose words with precision. But in describing the diversity of nature, scientists create new words — a new vocabulary of meanings for concrete objects — for that which exists but is outside our imagination. In so doing, they provide the words with which poets fashion dreams."

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The middle way

It was Quintus Horatius Flaccus in the first century BC who commented "Est modus in rebus", meaning that there is moderation in all things. And Horace took a beneficent view of the universe, and was not one for taking up any cause associated with extreme views or actions.

Although he had inevitably been drawn into the fierce contest between Julius Caesar and Brutus, and had been given a tribune's task by Brutus, Horace was relieved to be able to retreat to his Sabine farm after Philippi, and devote his time to poetry and other tranquil pursuits. In this he differed fundamentally from most of his near-contemporaries and from modern politicians, who must always take an extreme position regarding any real or fancied adversaries.

It is difficult to understand why a public figure is expected to adopt a fighting pose, and why anyone who expresses moderation and doubt should be looked down upon as a weakling. It is even more difficult to comprehend why an individual who has enjoyed years of political power should be motivated to resist any attempt made by someone else to assume the reins of power, to the extent of using force, bribes or threats to manipulate an allegedly democratic election. Yet such a thing repeatedly happens, and politicians blindly devoted to party tactics turn parliamentary debate into a vulgar slanging match of which a fourth-form schoolboy would feel ashamed.

Of course, those who hope to attain their desires through oratory can do nothing better than adopt an extreme and uncompromising position in their argument. Just as politicians have become suspect, so have lawyers, who sometimes reach incredibly illogical decisions through a "bully-boy" adversarial approach. This is an inheritance from antiquity, when an advocatus diaboli who took a novel view was forced into rhetorical argument with an advocatus Dei to decide the fate of some poor creature whose responsibility probably lay between two extremes.

It is high time we grew up and discarded mere rhetoric in favour of logical, cool-headed thinking. After all, it makes the difference between sense and sentiment. And if we use the art of reflection we shall produce a society less prone to violence.

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