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Le autrici sviluppano alcune riflessioni relative a una esperienza pluriennale di applicazione della metodologia di home visiting nella fascia 0-3 anni, sperimentata anche in casi per i quali si è verificato un intervento del tribunale per i minorenni. La cura nella costruzione dell'alleanza e nel potenziamento delle risorse presenti, l'interazione sistematica con tutte le figure professionali e i servizi coinvolti, l'attenzione alla delicatezza della fase di sviluppo, sono elementi importanti per il buon esito degli interventi sia nei contesti spontanei sia in quelli in tutela. Viene descritto il ruolo dell'operatrice di home visiting in funzione della collaborazione della famiglia e della possibilità di rendere più flessibili le rappresentazioni reciproche fra famiglie e servizi.

Urban particulate matter (PM) can affect green plants either via deposition on the above-ground biomass, where the contaminants can penetrate the leaf surface, or indirectly via soil-root interaction. In our investigation, a model experiment was carried out to demonstrate the direct effect of PM on tomato (Solanum lycopersicum L.) plant growth. A monitoring campaign of PM10 was conducted at an urban background site of Canosa (Apulia, Southern Italy) in four different days (1, 2, 3, 4). PM10 samples were collected for 24 hours on quartz fiber filter. The filters were then cut into two parts, one of which was used for the chemical characterization of the PM10 and one for the growth of tomato. Organic and elemental carbon and polycyclic aromatic hydrocarbons (PAHs) content were analysed for all the tested filters. Tomato plants were grown for 18 days directly on filters absorbed with PM10. The germination rate of tomato seeds and some parameters of seedlings primary growth of this plant species (length of root and shoot, their fresh weight and content of photosynthetic pigments in shoot) were used as laboratory indicators of phytotoxicity. Substantial differences were found in the growth of root apparatus respect to that of control plants. A significant decrease of primary root elongation, a large amount of secondary roots and a decrease in plant and root weights were found. To assess if the direct exposition of roots to PM10 induced an oxidative stress, reactive oxygen species (ROS) concentration was evaluated by measuring the fluorescence arising from oxidation of DCFH-DA in both control and treated roots. Quantitative analysis of ROS indicated that an oxidative burst in response to abiotic stress occurred in roots directly grown on PM10, whose detrimental effect was also confirmed by the findings on chlorophyll content and chlorophyll-to-carotenoid ratio.

This study shows the direct effect of atmospheric particulate matter on plant growth. Tomato ( Solanum lycopersicum L.) plants were grown for 18 d directly on PM10 collected on quartz fiber filters. Organic and elemental carbon and polycyclic aromatic hydrocarbons (PAHs) contents were analyzed on all the tested filters. The toxicity indicators (i.e., seed germination, root elongation, shoot and/or fresh root weight, chlorophyll and carotenoids content) were quantified to study the negative and/or positive effects in the plants via root uptake. Substantial differences were found in the growth of the root apparatus with respect to that of the control plants. A 17–58% decrease of primary root elongation, a large amount of secondary roots and a decrease in shoot (32%) and root (53–70%) weights were found. Quantitative analysis of the reactive oxygen species (ROS) indicated that an oxidative burst in response to abiotic stress occurred in roots directly grown on PM10, and this detrimental effect was also confirmed by the findings on the chlorophyll content and chlorophyll-to-carotenoid ratio.