Management of sewage sludge by composting using fermented water hyacinth.

The goal of the present research work was to assess the management of sewage sludge (SS) by composting using fermented water hyacinth (WHferm) as an amendment. The water hyacinth was fermented, and a higher production of volatile fatty acids (VFAs) (782.67 mg L(-1)) and soluble organic carbon (CSOL) (4788.34 mg L(-1)) was obtained using a particle size of 7 mm compared to 50 mm. For composting, four treatments (10 kg fresh weight each) were evaluated: treatment A (100 % SS + 0 % WHferm), treatment B (75 % SS + 25 % WHferm), treatment C (50 % SS + 50 % WHferm), and treatment D (25 % SS + 75 % WHferm). The WHferm added to SS, especially in treatments C (50 %) and D (75 %), increased the initial contents of organic matter (OM), organic carbon (CORG), CSOL, the C/N ratio, and the germination index (GI). The heavy metal content (HMC) (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) at the beginning was below the maximum allowed by USEPA regulations. All of the samples were free of Salmonella sp. from the beginning. The reduction of the CORG, CSOL, total Kjeldahl nitrogen (TKN), and C/N ratio indicated the degradation of the OM by day 198. The treatments with WHferm (B, C, and D) yielded higher values of electrical conductivity, cation exchange capacity, and GI than SS at day 198. No significant differences were observed in GI among the treatments with WHferm. The fecal coliforms were eliminated (<3 MPN g(-1)) and the helminths were reduced to ≤5 eggs/2 g during the process. The competition for nutrients and the presence of suppressive fungi of the genera Penicillium, Rhizopus, Paecilomyces (penicillin producers), and Fusariella isolated from the compost may have promoted the elimination of pathogens since no thermophile temperatures were obtained. WHferm as an amendment in the composting of SS improved the characteristics of the final product, especially when it was used in proportions of 25 and 50 %. An excellent product was obtained in terms of HMC, and the product was B class in terms of pathogens.

Estatura final de una población de prematuros con muy bajo peso al nacer / Final height in a population of preterm infants with very low birth weight

Los niños nacidos prematuros de muy bajo peso, tienen una mayor frecuencia de baja talla a la edad adulta. En la Argentina no contamos con reportes de estatura final de estos niños. Se evaluaron el peso y estatura de 46 jóvenes de la ciudad de Buenos Aires con antecedentes de prematurez y muy bajo peso al nacer egresados de 7 unidades neonatales de la ciudad de Buenos Aires y conurbano bonaerense, entre los años 1990 y 1995. Los 46 jóvenes (27 mujeres) tenían una edad promedio de 18.97 años (16.04 - 22.93). La estatura media de las mujeres fue de -0,71 sDS (0.20) y -0.75 sDS (0.22) en varones. Se detectó baja estatura en 2 mujeres (7.4%) y 1 varón (5.3%). La incidencia global de baja estatura es de 6.5% (AU)

Infants born prematurely with a very low birth weight more often have short stature in adulthood. In Argentina there are no reports on final height in these children. We evaluated weight and height of 46 adolescents and young adults from the city of Buenos Aires with a history of prematurity and very low birth weight who were discharged from seven Departments of Neonatology in the city of Buenos Aires and Greater Buenos Aires between 1990 y 1995. The 46 youth (27 females) had a mean age of 18.97 years (16.04 ­ 22.93). Mean height of the women was -0.71 SDS (0.20) and mean height of the men was -0.75 SDS (0.22). Low stature was observed in two women (7.4%) and one man (5.3%). Overall incidence of short stature was 6.5%. (AU)

Waterborne diseases in the state of Mexico, Mexico (2000-2005).

This paper reports a spatial-temporal examination of waterborne disease data from the State of Mexico, 2000 to 2005, by county as the spatial unit. It was found that the incidence of waterborne disease did not decrease during the period under study. Inequality between metropolitan areas and rural zones was observed. People living in population centres had lower incidence of water-related diseases, possibly due to better access to services. In all cases, children under five years old suffered a much higher relative morbidity than the population in general. Improvement of the water distribution network between 2000 and 2005 could explain the decrease in morbidity from 30% to 15%, for the total population, and from 34% to 18.5%, for children under five years old. Coverage of sewer services over the period was not substantially improved; as a result the coefficient of determination remained nearly constant: 16.5% for the total population and 25% for children under five. Maintenance and operation deficiencies in the water distribution and wastewater sanitation systems play an important role in the incidence of this type of disease. It was found that the institutional division of the territory does not correspond to the actual distribution of the risk areas.