RESUMO
Trail, Canada, has been the site of an active lead/zinc smelter for nearly a century. Since 1991, the Trail Community Lead Task Force has carried out blood lead screening, case management, education programs targeted at early childhood groups and the general community, community dust abatement, exposure pathways studies, and remedial trials. From 1989 through 1996, average blood lead levels of children tested for the first time declined at an average rate of 0.6 microg/dl/year, while blood lead levels in Canadian children not living near point sources appeared to be leveling off following the phase-out of leaded gasoline. Since there was no concurrent improvement in local environmental conditions during this time, it is possible that the continuing decline in Trail blood lead levels has been at least partly due to community-wide intervention programs. One year follow-up of children whose families received in-home educational visits, as well as assistance with home-based dust control measures, found that these specific interventions produced average blood lead changes of +0.5- -4.0 microg/dl, with statistically significant declines in 3 years out of 5. Education and dust control, particularly actions targeted toward higher risk children, appear to have served as effective and appropriate interim remedial measures while major source control measures have been implemented at the smelter site.
Assuntos
Poluição Ambiental/prevenção & controle , Intoxicação por Chumbo/prevenção & controle , Chumbo/sangue , Metalurgia , Colúmbia Britânica , Administração de Caso , Criança , Pré-Escolar , Poeira/prevenção & controle , Monitoramento Ambiental , Educação em Saúde , Humanos , Lactente , Chumbo/análise , Programas de Rastreamento , Modelos Biológicos , Poluentes do Solo/análise , Espectrofotometria Atômica , Fatores de TempoRESUMO
Regenerating neurons synthesize new, rapidly transported, growth-associated proteins which are thought to mediate the regeneration process. We have studied these proteins in the regenerating optic nerves of goldfish by using two-dimensional polyacrylamide gel electrophoresis coupled with gel fluorography and computer analysis. The results indicate that goldfish retinal ganglion cells produce 3 polypeptides which qualify as growth-associated proteins. Properties shared by each of these 3 polypeptides suggest that they may originate from a common precursor.
