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This study aimed to assess the chemical composition of the rainwater in three areas of different environmental impact gradients in Southern Brazil using the receptor model EPA Positive Matrix Factorization (EPA PMF 5.0). The samples were collected in a bulk sampler, from October 2012 to August 2014, in three sampling sites along with the Sinos River Basin: Caraá, Taquara, and Campo Bom. The major ions NH 4 + , Na + , K + , Ca 2+ , Mg 2+ , F - , Cl - , NO 3 - , SO 4 2- , and pH were analyzed, as well as identify the main emission sources. The most abundant cations and anions were Ca 2+ , Na + , Cl - , and SO 4 2- , respectively. The mean pH value in the Sinos River Basin during the study period was 6.07 ± 0.49 (5.13-7.05), which suggests inputs of alkaline species into the atmosphere. The most important neutralizing agents of sulfuric and nitric acids in the Sinos River Basin are Ca 2+ (NF = 1.36) and NH 4 + (NF = 0.57). The source apportionment provided by the EPA PMF 5.0 resulted in four factors, which demonstrate the influence of anthropogenic and natural sources, in the form of (a) industry/combustion of fossil fuels (F - and SO 4 2- ), (b) marine contribution (Na + and Cl - ), (c) crustal contribution (K + , Ca 2+ , and NO 3 - ), and (d) agriculture/livestock (NH 4 + ). Therefore, this study allows a more appropriate understanding of factors that contribute to rainwater chemical composition and also to possible changes in air quality.

The Brazilian Amazon has experienced considerable colonization in the last few decades. Family agriculture based on slash-and-burn enables millions of people to live in that region. However, the poor nutrient content of most Amazonian soils requires cation-rich ashes from the burning of the vegetation biomass for cultivation to be successful, which leads to forest ecosystem degradation, soil erosion and mercury contamination. While recent studies have suggested that mercury present in soils was transferred towards rivers upon deforestation, little is known about the dynamics between agricultural land-use and mercury leaching. In this context, the present study proposes an explanation that illustrates how agricultural land-use triggers mercury loss from soils. This explanation lies in the competition between base cations and mercury in soils which are characterized by a low adsorption capacity. Since these soils are naturally very poor in base cations, the burning of the forest biomass suddenly brings high quantities of base cations to soils, destabilizing the previous equilibrium amongst cations. Base cation enrichment triggers mobility in soil cations, rapidly dislocating mercury atoms. This conclusion comes from principal component analyses illustrating that agricultural land-use was associated with base cation enrichment and mercury depletion. The overall conclusions highlight a pernicious cycle: while soil nutrient enrichment actually occurs through biomass burning, although on a temporary basis, there is a loss in Hg content, which is leached to rivers, entering the aquatic chain, and posing a potential health threat to local populations. Data presented here reflects three decades of deforestation activities, but little is known about the long-term impact of such a disequilibrium. These findings may have repercussions on our understanding of the complex dynamics of deforestation and agriculture worldwide.

Objective: To determine the macronutrient and micronutrient contents of human milk from milk banks as well as to develop a supplement for addition to this milk that could satisfy the specific nutritional requirements of low birthweight newborns., Method: For the determination of macronutrients, 46 samples of pasteurized milk obtained from two milk banks were analyzed in triplicate: 26 samples of mature milk, 10 samples of foremilk and 10 samples of milk from mothers of preterm babies. Thirty of these samples (10 of each type of milk) were also analyzed for their micronutrient content. Following the determination of macronutrients and micronutrients, an easy-to-prepare supplement was developed. The supplement was made from protein hydrolysate powder and chelate minerals., Results: The nutritional content varied both among the different types of milk and among the donors of the same type of milk. The levels of macronutrients and micronutrients were below the requirements for low birthweight newborns. The mean composition (and standard deviation) observed for mature milk, foremilk, and preterm milk, respectively, was as follows: fats (g/100 mL), 2.56 (+/- 0.8), 2.48 (+/- 0.91), 2.48 (+/- 0.76); lactose (g/100 mL), 8.6 (+/- 0.93), 7.05 (+/- 0.92), 6.56 (+/- 1.41); protein (g/ 100 mL), 1.07 (+/- 0.22), 1.71 (+/- 0.29), 1.72 (+/- 0.4); calories (kcal/100 mL), 61.67 (+/- 8.92), 57.36 (+/- 8.37), 55.44 (+/- 8.00); calcium (mg/100 mL), 17.88 (+/- 5.56), 22.75 (+/- 10.24), 22.03 (+/- 9.39); magnesium (mg/100 mL), 2.15 (+/- 0.39), 2.64 (+/- 0.67), 2.16 (+/- 0.26); potassium (mg/100 mL), 35.53 (+/- 7.54), 43.75 (+/- 14.32), 44.37 (+/- 12.83); sodium (mg/100 mL), 16.27 (+/- 5.92), 43.36 (+/- 11.34), 37.98 (+/- 11.34); zinc (mg/100 mL), 0.46 (+/- 0.26), 0.75 (+/- 0.25), 0.72 (+/- 0.26); and phosphorus (mg/100 mL), 9.98 (+/- 1.72), 9.31 (+/- 4.30), 8.47 (+/- 2.43). After the addition of the supplement, the protein and mineral contents reached the levels recommended for low birthweight newborns., Conclusion: Based on our results obtained, the supplementation of human milk from milk banks is warranted for use with low birthweight newborns. The proposed supplement was shown to be practical and safe, and it did not interfere with the microbiological quality of human milk.

Wet deposition and related rainwater chemistry were studied at the Itatiaia massif, on which is settled the Itatiaia National Park (INP). Samples were simultaneously collected on a weekly basis over 12 months, using automated wet and dry samplers, at the INP-Headquarters (INP-Hq; altitude=820 m) and the Itatiaia Plateau (It-Pt; altitude=2460 m). Conductivity, pH, Na(+), K(+), Mg(2+), Ca(2+), NH(4)(+), Cl(-), NO(3)(-) and SO(4)(2-) were determined in 36 rainwater samples. Volume-weighted mean (VWM) pH was lower at the INP-Hq (4.9) than at the It-Pt (5.3). Very strong correlation between Cl(-) and Na(+) was found for the INP-Hq (r=0.99). At the Itatiaia massif, SO(4)(2-), NO(3)(-), and NH(4)(+) comprised together about 60% of the total inorganic ions and appear to exert the major control on rainwater pH.