Solid waste generation model validation and economic loss estimation due lack of recycling.

Urban Solid Waste Management (USWM) is one of the components that influences in the sustainable cities. It is a fundamental factor in achieving the Sustainable Development Goals (SDGs), 2030 agenda. This paper work aims to validate a mathematical model for solid waste generation and to estimate the economic loss due lack of recycling in the city of Campo Grande, State of Mato Grosso do Sul/Brazil. The model adopted was developed by Dias et. al. (2012), which allows projecting the mass of waste to be generated by the inhabitants from socioeconomic indicators, such as per capita income, social classes and size of population in a specific urban territory. Besides, waste composition was analyzed to determinate the value and share of the gravimetric characterization, in order to estimate the economic loss in areas, which there are no selective collection of Household Solid Waste (HSW). The model showed strong adherence, when compared to the real mass of HSW collected. The economic loss due to selective collection approaches nearly 9.6 million US$, or about 11 US$ per person per year. The study can provide support for economic evaluation of project sand public policies related to USWM executed in any other city with similar characteristics.

Short-term toxicity of ammonia, sodium hydroxide and a commercial biocide to golden mussel Limnoperna fortunei (Dunker, 1857).

Macrofouling bivalves are considered an ecological and technological problem worldwide. Control measures have been researched with Limnoperna fortunei, but without success. The aim of the manuscript is to test some alternatives to regulate this harmful invasive mollusk. Mortality and behavioral response (shell gaping) of Limnoperna fortunei exposed to three chemical compounds were evaluated. Values for LC50 96h were: 0.25 (0.24-0.27)mg/L NH3-N, 11.10 (7.45-16.55) mg/L MXD-100 and 88.51 (74.61-105.01)mg/L NaOH. Reduced gaping was observed beginning at concentrations of 0.31mg/L (NH3-N), 100mg/L (MXD-100) and 160mg/L (NaOH) and increased above these values. The percentage of individuals gaping after two hours at LC50 96h differed significantly (χ(2)=79.9; DF=3; p<0.001) in MXD-100 (50%), NaOH (0%), NH3-N (96.7%) and the controls (93.3%). This study contributes to the understanding of the relationship between toxicity and behavioral effects of some toxicants in L. fortunei.