Pleural cancer deaths increased across the study period, rising from 491 in 1976–1980 to 1,249 in 2006–2010. Around 1,319 pleural cancer deaths (264 deaths/year) are predicted for the five-year period 2016–2020. Forecasts up to 2020 indicate that this increase will continue, though the age-adjusted rates already show a trend towards a levelling-off in male mortality from 2001–2005, a trend corresponding to the lower risk in post-1960 generations. The lower rates and different mortality trend registered by women would appear to indicate that occupational exposure is possibly the single factor having most influence on this trend.
Previously published predictions  estimated that there would be 636 male pleural cancer deaths (95% CI 499–656) in the period 2007–2011 and a further 685 (95% CI 497–960) in the period 2012–2016. Current data show that in the five-year period 2006–2010 there were 897 pleural cancer deaths in men, which would correspond to 642 deaths due to pleural mesothelioma, assuming a mesothelioma/pleural cancer coefficient of 0.73. In the five-year period 2006–2010, there were approximately 261 more deaths than the figure predicted in 2008 (underestimate of 41%).
Unlike other studies [9, 15, 26], the APC computation of the prediction did not consider asbestos imports or their decline from the 1980s until 2002 (the year in which they came to a halt). The prediction did, however, consider the decreasing mortality in post-1950 cohorts, a decrease visible in the age-specific mortality rates and cohort effect shown in Figure 2. The lag between asbestos imports and pleural cancer deaths shown in Figure 3 (taking the maximum of both series into account) and confirmed by the modelling strategy, lasted 36 years, which corresponds to the induction period for mesothelioma . Future male pleural cancer mortality estimated by the asbestos import-based model accurately predicted the increase in pleural cancer deaths until 2008 but predicted a decrease in deaths from 2010 onwards.
The number of pleural cancer deaths among men predicted for the period 2011–2020 is 1898 under the APC-based model versus 1680 under the asbestos import-based model. The import-based model underestimates the deaths observed during 2011. This model lends excessive weight to the effect of the decline in asbestos imports, as a consequence of the simple statistical relationship established.
Because of the rarity of primary malignant tumours of the pleura other than mesothelioma, the number of deaths coded as pleural cancer could be considered a rough estimate of mesothelioma cases . Mesothelioma mortality estimates and projections are based on the ratio of pleural mesothelioma mortality to pleural cancer mortality. Thus, a factor of 0.81 was used in France to estimate pleural mesothelioma cases from the total number of pleural cancer deaths , and a factor of 0.73 was used in Italy .
From 2006 to 2011, there were 1096 male deaths in Spain coded as cancer of the pleura, and of these, 849 (77%) were coded as pleural mesotheliomas. In women, this percentage was 63% (436 pleural cancer deaths, 273 mesotheliomas). If these factors are applied to the pleural cancer deaths predicted for the period 2016–2020, then a total of 965 mesothelioma cases (742 in men and 223 in women) is obtained (193 deaths/year).
The number of mesothelioma deaths predicted for Spain is lower than that for other countries in the region [9, 15, 16]. This is because this country’s asbestos consumption has historically been lower. The use of bulk asbestos in Spain started in the early 1960s, at a later date than the rest of Europe. Consumption witnessed a remarkable increase until 1974, sharing highs in those years with other European countries. Thenceforth, however, following the same trend as seen in other countries, consumption went into a steady decline that continued until the product’s ban in 2002, with a slight increase at the end of the 1980s. Overall consumption in Spain was one-third lower than that of France and Italy, and half that of the United Kingdom [7, 8].
Spanish records however show far fewer mesothelioma-related deaths than would have been expected, i.e., 74% fewer than in France, 79% fewer than in Italy, and 88% fewer than in the United Kingdom in the year 2000. Several hypotheses can be postulated to explain this difference. Attention to the risks arising from exposure to asbestos in Spain was almost non-existent until the 1980s, making it difficult for this diagnosis to be assigned as the cause of death, in contrast to other countries in the region . On the other hand, each country’s prevailing economic risk activities are decisive, conditioning differences in asbestos exposure [30, 31].
Part of the increase in cases in Spain in the 1990s could be due to improvements in diagnosis of mesothelioma as a cause of death. It seems more plausible, however, that this increase is attributable to the effects of increased asbestos consumption, and that the introduction of regulatory measures and prohibitions were delayed in Spain and that this in turn led to the effects of exposure being extended.
The first preventive measures targeting asbestos use in Spain were implemented in 1984  and the ban on the use, production and marketing of asbestos fibres and any products containing these was introduced in 2001  and came into effect in December 2002. Subsequently, minimum health and safety requirements were brought in 2006 to cover work entailing a risk of exposure to asbestos . Such work essentially comprises the removal of installed asbestos, the maintenance, rehabilitation and demolition of buildings with asbestos-containing materials, and the transport, treatment and destruction of asbestos-containing waste.
Changes in death-coding criteria can also affect mortality trends. The decline in mortality rates in the five-year period 1986–1990 and the observed period effect (Figure 2d) are probably related to coding changes that took place in Spain at the time (when death-coding duties were transferred to the Autonomous Regions).
Møller’s proposal for estimating future mortality was used in this study . This method, based on the classic “generalised linear model” , is implemented in the Norpred package, which has not only been successfully used in several European countries [35–37] but has also been empirically shown to improve prediction validity . Comparative prediction-quality studies using different methods have recommended the use of Norpred in cases such as ours, where there is a cohort effect identified by age-period-cohort analysis .
The disappearance of occupational exposure to asbestos should lead to a reduction in the number of deaths among men to levels equivalent to those recorded for women, which are two thirds lower. Mortality caused by community exposure to a carcinogenic risk factor such as asbestos is characterised by a great degree of inertia, and its catastrophic consequences will persist and remain in evidence until the disappearance of the last surviving representatives of the exposed cohorts. To this must be added the fact that there were no preventive measures aimed at reducing worker exposure, nor any emission controls until as late as 1984. It can thus be assumed that occupationally-related deaths due to pleural mesothelioma will continue to occur in Spain until at least 2040, bearing in mind the fact that in 2006 the life expectancy of Spanish men born in the 1960s was 37.4 years. Moreover, account must be taken of the enormous amount of asbestos which was used in the construction of buildings (mostly offices, entertainment venues, public facilities and car parks) from 1965 to 1985  and which will be mobilised for subsequent demolition or maintenance purposes. Improved education regarding protection from exposure during the demolition or disposal of asbestos-containing material as well as more adequate measures for reducing risk of mesothelioma are thus called for . Similarly, the qualification and training of health care workers in disease detection and diagnosis must also be improved so as to ensure that these diseases do not go undetected.