Suchergebnisse

La mise en oeuvre à grande échelle des principes de l'agroécologie et de l'agriculture biologique est une option proposée pour répondre aux enjeux de durabilité de l'agriculture. Toutefois la capacité de tels systèmes à répondre aux enjeux de sécurité alimentaire globale reste posée. La place de l'élevage est au centre du débat, notamment en raison de son rôle dans le bouclage des cycles des éléments minéraux et du rôle des prairies dans les rotations culturales. Cependant, l'efficience de transformation par les animaux des ressources végétales reste faible, ce qui pose particulièrement problème pour les monogastriques qui rentrent fortement en concurrence avec l'homme pour l'utilisation des céréales et des oléoprotéagineux. Ainsi, la place de l'élevage dans des scénarios alimentaires durables sera déterminée par sa capacité à utiliser d'une part les ressources fourragères issues des systèmes de culture ou des prairies permanentes, d'autre part les co-produits des cultures non directement utilisables par l'homme. Nous discutons dix facteurs majeurs à mobiliser pour envisager une contribution optimale de l'élevage à une production agricole durable. Leur mise en oeuvre nécessitera d'affiner l'identification de leurs interactions et de leur adjoindre des facteurs externes de type démographique et climatique, pour élaborer et analyser des scenarios prospectifs de long terme. Abstract: The central role of livestock farming in scenarios for a more sustainable food system The implementation of the principles of agroecology and of organic farming at a large scale is an option to enhance the sustainability of agricultural systems. However, the ability of these systems to contribute to global food security is still debated. Livestock is at the centre of this debate, particularly because of its key role to close nutrient cycles in cropping systems, and because of the role of temporary grasslands to control diseases, weeds and pests in crop rotations. However, livestock feed efficiency is low, while pigs, poultry and dairy ...

The implementation of the principles of agroecology and of organic farming at a large scale is an optionto enhance the sustainability of agricultural systems. However, the ability of these systems to contributeto global food security is still debated. Livestock is at the centre of this debate, particularly because of itskey role to close nutrient cycles in cropping systems, and because of the role of temporary grasslandsto control diseases, weeds and pests in crop rotations. However, livestock feed efficiency is low, whilepigs, poultry and dairy cows compete with humans for the use of crops and soybean. Thus, movingtowards more sustainable livestock farming systems requires ruminants to be grazed on fodderresources from cropping systems and on permanent grasslands, and pigs and poultry to increase theiruse of crop by-products. Here, we discuss ten key factors that would enhance the contribution oflivestock to sustainable agricultural systems. Their implementation requires on the one hand to refinethe identification of their interactions and, on the other hand, to jointly account for demographic andclimatic factors in long-term prospective scenarios. ; La mise en œuvre à grande échelle des principes de l'agroécologie et de l'agriculture biologique est uneoption proposée pour répondre aux enjeux de durabilité de l'agriculture. Toutefois la capacité de telssystèmes à répondre aux enjeux de sécurité alimentaire globale reste posée. La place de l'élevage estau centre du débat, notamment en raison de son rôle dans le bouclage des cycles des élémentsminéraux et du rôle des prairies dans les rotations culturales. Cependant, l'efficience de transformationpar les animaux des ressources végétales reste faible, ce qui pose particulièrement problème pour lesmonogastriques qui rentrent fortement en concurrence avec l'homme pour l'utilisation des céréales etdes oléoprotéagineux. Ainsi, la place de l'élevage dans des scénarios alimentaires durables seradéterminée par sa capacité à utiliser d'une part les ressources fourragères ...

Abstract

Objectives
In Italy, the highest pleural cancer mortality and incidence have been observed among Italian regions where the 2 largest Italian shipyards were (and are) located. The objective of this study was to assess the exposure–response relationship for mesothelioma among male workers employed in the Monfalcone, Italy, shipyard.


Methods
We conducted a necropsy-based case–control study. Cases (N = 102) were mesothelioma decedents and controls were those with lung cancer (N = 84). Complete job histories were available; the lung fibre content was measured using a scanning electron microscope with X-ray fluorescence, after sample preparation according to the European Respiratory Society guidelines. Odds ratios and 95% confidence intervals of mesothelioma by fibre type and lung fibre burden, as a categorical or continuous variable, were assessed by unconditional logistic regression, adjusted for age and time since exposure cessation. Analyses for the amphibole and chrysotile lung fibre burden were mutually adjusted. We calculated a cumulative exposure index by applying a job-exposure matrix to the job histories of study cases and assessed its correlation with the lung fibre burden.


Results
We found an odds ratio of 22.0 (confidence intervals 5.66–85.7) for the highest lung fibre burden category (mean 43.8 million total asbestos fibres per gram of dry tissue) compared with the reference (mean 0.48). Using log10-transformed lung fibre burden, we found that the odds ratio was 3.71 (confidence intervals 2.03–6.79) for a 10-fold lung fibre burden increase. Results for the amphibole lung fibre burden were similar. Odds ratios increased over chrysotile lung fibre burden categories (P-trend = 0.025), and the odds ratio for a 10-fold increase was 4.73 (confidence intervals 0.32–70.4).


Conclusions
The cumulative exposure index was correlated with total and amphibole lung fibre burden, but not with chrysotile lung fibre burden. Mesothelioma risk was proportional to total, amphibole, and chrysotile lung fibre burden in shipyard workers.

Abstract

Background
Malignant pleural mesothelioma (MPM) due to environmental and familial (domestic) asbestos exposure is well recognized. However, information on cumulative asbestos dose in subjects affected by MPM is limited.


Objectives
To evaluate the residual lung asbestos fibre and asbestos body burden in women with MPM with past environmental and/or familial asbestos exposure.


Methods
We collected lung samples from autopsies regarding 15 non-occupationally asbestos-exposed MPM cases, divided in three groups: (i) familial exposure from the Fincantieri shipyards in Monfalcone (No. 7), (ii) environmental and familial asbestos exposure from the asbestos-cement plant Fibronit in Broni (No. 6), and (iii) environmental exposure from the Fibronit plant (No. 2). Asbestos body (AB) and fibres (AF) per gram of dry lung tissue were counted by optical and scanning electron microscopy, respectively, and expressed as geometric means and standard deviations (GM, GSD).


Results
GM/GSD of AB counts were 6123/9.6 (Group 1), 13 800/10.4 (Group 2), and 8400/1.1 (Group 3); GM/GSD of AF were 0.6/2.1 (Group 1), 7.9/2.1 (Group 2), and 6.0/2.3 (Group 3) million. Pleural plaques were observed in 12 cases.


Conclusions
Exclusive familial exposure to asbestos determined cumulative doses close to those observed in moderate occupational exposure circumstances. Our results also suggest that combined environmental and familial exposures may cause unexpectedly high cumulative fibre doses.