Biomolluscicides development is of great interest in pest management to avoid the effects on the environment caused by synthetic molluscicides. The Species: Solanum mammosum L., Sapindus saponaria L. and Jatropha curcas L. have demonstrated molluscicidal properties against Pomacea canaliculata. This study was carried with mixtures of aqueous extracts of these plants in order to check for a synergistic effect between them. Extracts obtained from each species were evaporated and lyophilized. By using a simplex centroid design were obtained ten mixes for testing. All of them were diluted to 500ppm and tested on adult snails for 24 hours of exposure followed by 24 hours of recovery on tab water. Those mixes that showed the best results of mortality were chosen to determine the median lethal dose. The formulations S. saponaria (100%) and S. mammosum -S. saponaria (50%-50%) showed the best results of mortality with LD50 values of 24.04 ppm and 17.78 ppm respectively, with no significant differences between them (p> 0.05). These results showed that a synergistic effect is not produced in the activity of these plants when the extracts mixture was performed.

Aedes aegypti is a mosquito that carries dengue virus, yellow fever and other diseases transmitted to humans. Organophosphorus larvicides are used to control the proliferation of this mosquito, which has generated a high degree of resistance; hence, new alternatives such as bio-larvicides formulated with plant extracts are of great interest. The aims of this study were to evaluate the ethanolic extract of Azadirachta indica leaves as a larvicide against Aedes aegypti and to determine the main compounds present in it by GC-MS. In the assay, three concentrations of ethanolic extract were used (10 mg L-1, 20 mg L-1, and 50 mg L-1). This was performed thrice against a positive control (commercial larvicide: spores and endotoxic crystals of Bacillus thuringiensis var. israelensis Serotype H-14) and negative control (water). After 72 h of incubation, it was observed higher larval mortality (93%) in the ethanolic extract at a concentration of 50 mg L-1; the extracts at 10 mg L-1 and 20 mg L-1 shown larval mortality of 47% and 70%, respectively. The majority compound determined by the GC-MS analysis was phytol (14.4% area). The results obtained in this study demonstrated the larvicidal potential of the ethanolic extract of A. indica against larvae of A. aegypti.

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Coarse particulate matter (PM 10) concentrations and chemical composition were monitored from 2014 to 2017 at three sampling sites in the Metropolitan Region of Rio de Janeiro, namely Botafogo, Gávea, and Gericinó. All sites are located close to the 2016 Olympic Game arenas. The average annual PM 10 concentrations were above the limits recommended by the World Health Organization (WHO) at all sampling sites. Of all the analyzed water-soluble ions, the highest concentrations were obtained for NO 3 − , SO 4 2− , Cl − and Na +. Sulfate displayed a higher anthropic contribution (ca. 70%). Iron and copper were present in all samples, originated from soil resuspension and traffic (fuels and brakes, among others). Overall, civil works to restructure the city and the construction of the Olympic Game arenas increased PM 10 and some of its constituent levels prior to 2016. After the Olympic Games, PM 10 concentrations have decreased, due to governmental policies regarding traffic planning and civil work finalization.

The 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRAP), and semivolatile compounds of Conyza bonariensis L. leave extract and fractions are discussed. A methanolic crude extract was obtained through maceration, and subsequently, n-hexane, chloroform, and ethyl acetate fractions were collected using a solvent-solvent partition. Total phenols, flavonoids, and antioxidant activity assays were performed in an ultraviolet-visible (UV-Vis) spectrophotometer, and the results were expressed as Gallic Acid, Quercetin, and Trolox equivalents respectively. The findings achieved indicate that ethyl acetate fraction showed the highest DPPH radical scavenging capacity (90.69±3.16%) at 500 µg mL-1, and reduced the ferric tripyridyltriazine complex (Fe3+-TPTZ) with values between 19.68 and 2,355.37 mg Trolox equivalent (TE) g-1. It was identified 28 phytoconstituents through Gas chromatography-mass spectrometry (GC-MS). The scavenging activity of ethyl acetate fraction could be correlated mostly to the presence of eugenol, trans-isoeugenol, lucenin-2, methyl salicylate, and syringic acid. This study reveals that the ethyl acetate fraction could be used as a good source of antioxidants for health benefits.

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ASSESSMENT OF THE CONCENTRATION AND INORGANIC COMPOSITION OF PARTICULATE MATTER COLLECTED IN THE STATE OF RIO DE JANEIRO. Cities urbanization and modernization increase emission sources, contributing to particulate matter (PM) composition heterogeneity and enhance the risk to human health and environment. This paper intends to survey the studies on particulate matter carried out in the state of Rio de Janeiro. The sampling of PM is generally made using Hi-Vol samplers to collect particles in fiberglass filter during 24 h every 6 days. Spectrometric techniques are used for elemental determination and ion chromatography for water-soluble species. The Environmental State Institute (INEA) is responsible for air quality monitoring in RJ. After 30 years, air quality standards have become more stringent and have included new pollutants. The highest PM concentrations were found in urban and industrial sites and the lowest in places away from urban activities or near the coast. Over the years, PM concentrations near steel complexes reduced even below the limits and varied at other places, remaining above the limits. Nitrate and sulfate were the main ionic compounds, and Fe, Al and Zn were the major elements in PM samples. It was also found Ni, V, Cd, Pb and Cu. Although air quality monitoring is efficient, it still needs to be improved to help reduce the environmental impact.

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