Smoking deaths

The fire death rate in the United States is decreasing, dropping from a rate of 76 per million in the 1940s, when most constmction and decorative products were made of natural materials, to 29 per million in the 1980s, by which time, PVC had replaced natural materials in numerous appHcations (189). This downward trend can be attributed in large part to improved building codes and the broader use of sprinkler systems and smoke detectors. However, the increased use of more fire-resistant materials, such as PVC, deserves part of the credit for this improvement. 

Fig. 18-4. Daily air pollution (S02and smoke) and deaths during the 1952 London episode. Source Adapted from Wilkins (4).

From the commencement of the fog and low visibility, many people experienced difficulty breathing, the effects occurring more or less simultaneously over a large area of hundreds of square kilometers. The rise in the number of deaths (Fig. 18-4) paralleled the mean daily smoke and sulfur dioxide concentrations daily deaths reached a peak on December 8 and 9, with many of them related to respiratory troubles. Although the deaths decreased when the concentrations decreased, the deaths per day remained considerably above the pre-episode level for some days. Would most of the persons who died have died soon afterward anyway If this were the case, a below-normal death rate would h ve occurred following the episode. This situation did not seem to exist, but detailed analysis was complicated by increased deaths in January and February 1953 which were attributed primarily to an influenza outbreak. 

An air pollution episode responsible for approximately 300 excess deaths occurred in London between November 26 and December 1, 1948. Concentrations of smoke and sulfur dioxide were 50-70% of the values during the 1952 episode. 

Records show that more fatalities occur through victims being suffocated by smoke or poisoned by toxic gases emitted during a fire than by being burnt to death. This is particularly worrying when it is realised that many additives incorporated into a polymer to retard its flammability are often found to increase the amount of smoke emitted as the rate of flame propagation decreases. Most... 

The use of fire retardants in polymers has become more complicated with the realisation that more deaths are probably caused by smoke and toxic combustion products than by fire itself. The suppression of a fire by the use of fire retardants may well result in smouldering and the production of smoke, rather than complete combustion with little smoke evolution. Furthermore, whilst complete combustion of organic materials leads to the formation of simple molecules such as CO2, H2O, N2, SO2 and hydrogen halides, incomplete combustion leads to the production of more complex and noxious materials as well as the simple structured but highly poisonous hydrogen cyanide and carbon monoxide. 

Chronic obstructive pulmonary disease (COPD) affects over 5% of the adult population, is the fourth leading cause of death worldwide and is the only major cause of mortality that is increasing worldwide. It is an inflammatory disorder of the lungs, caused mainly, but not exclusively, by cigarette smoking. 15-20% of smokers develop COPD. 

True. Smoking tobacco is one of the most common avoidable causes of illness and death in most countries. 

True. Nicotine, carbon monoxide and other harmful chemicals from the burning tobacco travel in the mother s bloodstream and can reach the foetus. This can result in impaired development and reduced birth weight. Tobacco smoke can also be harmful to young children and babies (sudden infant death syndrome). 

The a-tocopherol, P-carotene (ATBC) Cancer Prevention study was a randomised-controlled trial that tested the effects of daily doses of either 50 mg (50 lU) vitamin E (all-racemic a-tocopherol acetate), or 20 mg of P-carotene, or both with that of a placebo, in a population of more than 29,000 male smokers for 5-8 years. No reduction in lung cancer or major coronary events was observed with any of the treatments. What was more startling was the unexpected increases in risk of death from lung cancer and ischemic heart disease with P-carotene supplementation (ATBC Cancer Prevention Study Group, 1994). Increases in the risk of both lung cancer and cardiovascular disease mortality were also observed in the P-carotene and Retinol Efficacy Trial (CARET), which tested the effects of combined treatment with 30 mg/d P-carotene and retinyl pahnitate (25,000 lU/d) in 18,000 men and women with a history of cigarette smoking or occupational exposure to asbestos (Hennekens et al, 1996). 

Cardiovascular disease (CVD) is one of the leading causes of death worldwide. There are a number of established risk factors including serum cholesterol levels, smoking and family history, which are responsible for between 50 and 75% of the CVD cases, with the remainder due to factors that cause atherosclerosis. Estrogen treatment such as hormone replacement therapy is known to protect against CVD by decreasing the levels of low-density... 

Both the general population and workers may be exposed to 241 Am from the production, distribution, and use of ionization chamber smoke detectors. The NRC investigated exposure relating to this device. Their 1979 report concluded that the sum of doses to the population resulting from production, distribution, use, and disposal of 14 million smoke detectors containing 3 pCi (100 kBq) of 241Am each (over 3 times that presently used) that were distributed in 1978 would result in a collective total body dose of 1,100 person-rem (11 person-Sv)—much lower than that which could potentially result in one cancer death (NRC 1979). Exposure to 241Am could result from improper disposal of smoke detectors. The detector could be broken and then disposed of in a municipal landfill or incinerated. The 241 Am from the broken detector could be consumed by a child. 

In adults, a study of 75 autopsies of persons who had resided in a soft-water, leached soil region of North Carolina found a positive correlation between lead level in the aorta and death from heart-related disease (Voors et al. 1982). The association persisted after adjustment for the effect of age. A similar correlation was found between cadmium levels in the liver and death from heart-related disease. (Aortic lead and liver cadmium levels were considered to be suitable indices of exposure.) The effects of the two metals appeared to be additive. Potential confounding variables other than age were not included in the analysis. The investigators stated that fatty liver (indicative of alcohol consumption) and cigarette smoking did not account for the correlations between lead, cadmium and heart-disease death. 

Haglund B, Cnattingius S. 1990. Cigarette smoking as a risk factor for sudden infant death syndrome A population-based study. Am J Public Health 80 29-32. 

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