[Algorithm for assessment of exposure to asbestos]. / Proposta di algoritmo per la valutazione stimata dell'esposizione lavorativa ad amianto.

There is no universally approved method in the scientific literature to identify subjects exposed to asbestos and divide them in classes according to intensity of exposure. The aim of our work is to study and develope an algorithm based on the findings of occupational anamnestical information provided by a large group of workers. The algorithm allows to discriminate, in a probabilistic way, the risk of exposure by the attribution of a code for each worker (ELSA Code--work estimated exposure to asbestos). The ELSA code has been obtained through a synthesis of information that the international scientific literature identifies as the most predictive for the onset of asbestos-related abnormalities. Four dimensions are analyzed and described: 1) present and/or past occupation; 2) type of materials and equipment used in performing working activity; 3) environment where these activities are carried out; 4) period of time when activities are performed. Although it is possible to have informations in a subjective manner, the decisional procedure is objective and is based on the systematic evaluation of asbestos exposure. From the combination of the four identified dimensions it is possible to have 108 ELSA codes divided in three typological profiles of estimated risk of exposure. The application of the algorithm offers some advantages compared to other methods used for identifying individuals exposed to asbestos: 1) it can be computed both in case of present and past exposure to asbestos; 2) the classification of workers exposed to asbestos using ELSA code is more detailed than the one we have obtained with Job Exposure Matrix (JEM) because the ELSA Code takes in account other indicators of risk besides those considered in the JEM. This algorithm was developed for a project sponsored by the Italian Armed Forces and is also adaptable to other work conditions for in which it could be necessary to assess risk for asbestos exposure.

The effects of two different water management regimes on flooding and mosquito production in a salt marsh impoundment.

Over two years, the management regimes of: 1) opening a southeast Florida salt marsh impoundment to the adjacent estuary with culverts through the dike, then, 2) passively retaining water with flapgate risers was studied to determine the effects on marsh flooding and resultant mosquito production. Larval dipping demonstrated that all broods occurred at elevations of 0.25-0.90 ft (= 0.08-0.27 m) NGVD. Mosquito production differed significantly between some sampling quadrats and 65 (out of 75) broods were produced in the spring and summer from rainfall. Without artificial pumping, trapping of rainfall with flapgate risers aided in eliminating oviposition sites but still allowed mosquito production in some marsh locations. Even though tidal flooding permitted larvivorous fish access to mosquito larvae, they were not able to provide adequate control to eliminate larviciding.

Distribution of mosquitoes in different wastewater stages of secondarily treated domestic effluent and untreated citrus washwater.

In Indian River County, Florida, mosquito populations were monitored weekly for 12 months in early and more advanced treatment stages of secondarily treated domestic wastewater and also in untreated primary and secondary citrus packing house washwater. Well defined differences in mosquito species abundances for early vs. late wastewater stages existed. In the early levels of secondarily treated effluent and in the primary citrus washwater, Culex quinquefasciatus populations were dominant. In the later wastewater stages of both systems, Cx. nigripalpus, Anopheles spp. and Uranotaenia spp. were more common. Seasonal Culex spp. abundance patterns were apparent at some but not all study sites. Water chemistry measurements demonstrated that both systems contained relatively low levels of nutrient-related parameters with large concentration variability.