Long-term characterization, lagoon treatment and migration potential of landfill leachate: a case study in an active Italian landfill.

The elaboration of 10 years of monitoring of leachate quality and quantity, leachate treatment and degree of contamination of soil and surface waters at the Tre Monti site--an active, 4-million-m(3) landfill in Northern Italy--is presented in this study. A hydrological model of leachate production is applied, with a good match of the experimental data. The concentrations of all leachate components except sulfate are characterized by fluctuations over a constant or increasing value. Different ways of interpreting leachate quality data are discussed; the elaboration indicates that the pollutant load on the leachate treatment facility will remain basically constant as long as waste will be added to the landfill. The analysis of the data relative to 10 years of leachate pre-treatment in the adjoining, non-aerated lagoon system indicates that a significant removal is achieved for most leachate components; the operational conditions of the plant are described, and the removal mechanisms are discussed. Finally, the potential for contamination of soil and surface waters is examined by analyzing long-term quality trends of the sub-superficial waters sampled near the lagoons and by means of an analytical campaign conducted on clay cores sampled near and underneath the treatment ponds. The experimental values indicate that the clay layer located under the entire site offers an effective barrier to the migration of leachate contaminants.

Response to infliximab is related to disease duration in paediatric Crohn's disease.

BACKGROUND: Infliximab is an effective therapy in adult patients with refractory and fistulizing Crohn's disease. Experience in children is still limited. AIM: : To evaluate the experience in 22 children and adolescents treated with infliximab with refractory and/or fistulizing Crohn's disease, and to compare duration of response in children between early Crohn's disease and late Crohn's disease. METHODS: The experience in 22 children and adolescents treated with a total of 73 infusions was evaluated retrospectively. Treatment indication was refractory Crohn's disease in 9/22 patients, fistulizing Crohn's disease in 7/22 patients and both these conditions in 6/22. All patients with refractory Crohn's disease had late Crohn's disease (> 1 year), whereas 6/13 patients with fistulas had early disease (< 1 year). RESULTS: Mean Paediatric Crohn's Disease Activity Index (PCDAI) decreased from 41.2 to 16.2 at 4 weeks (P < 0.01), and to 15.4 at 18 weeks (P < 0.01). Mean PCDAI at 18 weeks in children with early Crohn's disease and late Crohn's disease was 5.5 and 18.1, respectively (P < 0.05). Complete closure of fistulas was obtained in 5/6 children with early Crohn's disease and in 2/7 children with late Crohn's disease. Immediate adverse reactions were observed in two children. CONCLUSIONS: Infliximab is a highly effective treatment in children and adolescents with both severe refractory or fistulizing Crohn's disease. Children with early Crohn's disease have a higher chance of prolonged response to infliximab than children with late Crohn's disease.