Policies and regulations for Brazil’s artisanal gold mining sector: analysis and recommendations

In Brazil, artisanal and small-scale gold mining (ASGM) produces in the range of 6 tonnes of gold (Au) per annum, and employs approximately 200,000 people. Most of this mining activity is in the Amazon region, where miners have been extracting gold for more than 40 years. In the Tapajos River Basin, assessments indicate that around 99% of miners operate without the environmental and mining permits required by law. This is a result of a combination of unrealistic or lack of proper policies and regulations, lack of political will, lack of infra-structure to enforce the existing regulations and lack of incentives to miners to comply with legal requirements.In this article, we analyze a group of 20 laws, decrees and resolutions in Brazil, focusing on how idiosyncrasies in these regulations reveal gaps between policy and reality in ASGM areas. Artisanal miners operate in vast and remote areas and the government lacks the resources (personnel, vehicles, information and materials) to enforce the laws. Our analysis emphasizes the need for creating new government commitments and identifying priority areas where government agents can focus their efforts.There is no single solution for the environmental, health, technical and socio-economic problems associated with ASGM. However, a realistic approach should consider improving the level of education of miners, creating government programs to provide technical assistance in the field, simplifying administrative procedures and ensuring adequate measures for enforcement.     

Antimicrobial susceptibility of Escherichia coli isolated from shrimp (Litopenaeus vannamei) and pond environment in northeastern Brazil

This study aimed to test the susceptibility of Escherichia coli strains isolated from the water, bottom sediments and individuals cultivated in shrimp farm ponds, to antibiotics belonging to different families, namely B-Lactams: Imipenem (IPM; 10 μ g), Ampicillin (AMP; 10 μ g), Cephalothin (CEP; 30 μ g), Cefoxitin (FOX; 30 μ g), Ceftriaxone (CRO; 30 μ g); Tetracycline: Tetracycline (TCY; 30 μ g); Aminoglycosides: Gentamicin (GEN; 10 μ g), Amikacin (AMK; 30 μ g); Chloramphenicol: Chloramphenicol (CHO; 30 μ g); Fluoroquinolones: Ciprofloxacin (CIP; 5 μ g); Nitrofurans: Nitrofurantoin (NIT; 300 μ g); Sulfonamides: Trimethoprim-Sulfamethoxazole (SXT; 30 μ g); Quilononas: Nalidixic Acid (NAL; 30 μ g). In the laboratory, the method of dissemination (Test Kirby-Bauer) was performed in order to fulfill the antibiogram tests. The results showed high indices of resistance to Imipenem, Cephalothin and Ampicillin. Chloramphenicol, Nitrofurantoin, Cefoxitin, Ceftiaxone and Ciprofloxacin have displayed the highest index of sensitive strains. The antibiotic resistance index (ARI) and the multiple resistance index (MAR) varied within the ranges of 0.068–0.077 and 0.15–0.39, respectively. More than 90.5% of strains of Escherichia coli showed a variety of resistance profiles to the tested antibiotics. The high indices of resistance may be a consequence of indiscriminate use of antibiotics, but also the transfer of resistance through mobile genetic elements found in shrimp farms.     

Effect of lanthanum loading on nanosized CeO2-ZnO solid catalysts supported on cordierite for diesel soot oxidation

We report the application of a solid lanthanum–ceria–zinc catalyst in the catalytic regeneration of diesel particulate filters(DPF) in diesel engines.We synthesized a CeO_2–ZnO–La_2O_3(Ce–Zn–La) mixed oxide by a lactic acid-mediated sol–gel method,which efficiently coated cordierite substrates for soot capture and combustion.We studied the effects of La loading on the physicochemical and catalytic properties of Ce–Zn mixed oxide during lowtemperature soot combustion processes.We characterized the synthesized catalysts by X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FTIR),N2 adsorption,Raman spectroscopy,oxygen storage capacity(OSC),and scanning and transmission electron microscopy(SEM and TEM).Thermogravimetric and differential thermal analysis(TGA/DTA)confirmed that the catalysts effectively reduced the soot oxidation temperature.The ternary Ce–Zn–La mixed oxide catalyst with Ce/Zn/La atomic ratio of 2:1:0.5 had the highest catalytic activity and promoted soot oxidation at temperatures below 390°C.This indicated that the large number of oxygen vacancies in the catalyst structure generated oxygen species at low temperatures.Raman spectroscopy measurements revealed the presence of oxygen vacancies and lattice defects in Ce–Zn–La samples,which were key parameters concerning the stability and redox properties of the prepared catalysts.     

Geochemistry,mineralogy, solid-phase fractionation and oral bioaccessibility of lead in urban soils of Lisbon

An urban survey of Lisbon, the largest city in Portugal, was carried out to investigate its environmental burden, emphasizing metallic elements and their public health impacts. This paper examines the geochemistry of lead (Pb) and its influence on human health data. A total of 51 soil samples were collected from urban recreational areas used by children to play outdoors. The semi-quantitative analysis of Pb was carried out by inductively coupled plasma mass spectrometry after an acid digestion. X-ray diffraction was used to characterize the soil mineralogy. The solid-phase distribution of Pb in the urban soils was investigated on a subset of 7 soils, out of a total of 51 samples, using a non-specific sequential extraction method coupled with chemometric analysis. Oral bioaccessibility measurements were obtained using the Unified BARGE Method developed by the Bioaccessibility Research Group of Europe. The objectives of the study are as follows: (1) investigation of Pb solid-phase distribution; (2) interpretation of Pb oral bioaccessibility measurements; (3) integration of metal geochemistry with human health data; and (4) understanding the influence of geochemistry and mineralogy on oral bioaccessibility. The results show that the bioaccessible fraction of Pb is lower when major metal fractions are associated with less soluble soil phases such as Fe oxyhydroxides, and more increased when the metal is in the highly soluble carbonate phase. However, there is some evidence that the proportion of carbonates in the soil environment is also a key control over the oral bioaccessibility of Pb, irrespective of its solid-phase fractionation.     

Road traffic deaths in Brazil: rising trends in pedestrian and motorcycle occupant deaths

Objective: According to the World Health Organization, the global burden of road traffic mortality exceeds 1.27 million people annually; over 90 percent occur in low- and middle-income countries. Brazil's road traffic mortality rate of ～20 per 100,000 is significantly higher than nearby Chile or Argentina. To date, there has been very little information published on road traffic fatalities among vulnerable road users (VRUs) in Brazil. Methods: Road traffic fatality data from 2000 to 2008 were extracted from Brazil's Mortality Information System (SIM). Road traffic deaths were extracted using the International Classification of Diseases (ICD-10) V-codes (V01-V89) and then subcategorized by VRU categories. Information was then disaggregated by gender, age, and region. Results: In 2008, 39,211 deaths due to road traffic injuries were recorded in Brazil, resulting in a crude mortality rate of 20.7 per 100,000 inhabitants. Pedestrian mortality averaged 5.46 deaths per 100,000 between 2000 and 2008. The mortality rate for elderly pedestrians (80+ years) is 20.1 per 100,000, over 10 times that of 0- to 9-year-olds. In the past decade, motorcycle occupant mortality has dramatically increased by over 300 percent from 1.5 per 100,000 in 2000 to 4.7 per 100,000 in 2008. The 20- to 29-year age group remains most affected by motorcycle deaths, with a peak fatality rate of 10.76 per 100,000 in 2008. The north and northeast regions, with the lower per capita gross domestic product (GDP), have higher proportions of VRU deaths compared with other regions. Conclusions: Vulnerable road users are contributing an increasing proportion of the road traffic fatalities in Brazil. Nationally, elderly pedestrians are at particularly high risk and motorcycle fatalities are increasing at a rapid rate. Less prosperous regions have higher proportions of VRU deaths. Understanding the epidemiology of road traffic mortality in vulnerable road user categories will better allow for targeted interventions to reduce these preventable deaths.     

Positive association between social and extra-pair mating in a polygynous songbird, the dickcissel (Spiza americana)

In polygynous species, males appear to gain additional offspring by pairing with multiple females simultaneously. However, this may not be true if some females copulate outside of the social pair bond. Polygynous males could experience lower paternity because of trade-offs among gaining multiple social mates, guarding fertility with these mates, and pursuing extra-pair matings. Alternatively, polygynous males could simultaneously gain extra social mates and have high paternity, either because of female preferences or because of male competitive attributes. We tested four predictions stemming from these hypotheses in a facultatively polygynous songbird, the dickcissel (Spiza americana). Unlike most previous studies, we found that males with higher social mating success (harem size) also tended to have higher within-pair paternity and that the number of extra-pair young a male sired increased significantly with his social mating success. Females that paired with mated males were not more likely to produce extra-pair young. In contrast, extra-pair paternity was significantly lower in the nests of females whose nesting activity overlapped that of another female on the same territory. This pattern of mating was robust to differences in breeding density. Indeed, breeding density had no effect on either extra-pair mating or on the association between polygyny and paternity. Finally, nest survival increased with harem size. This result, combined with the positive association between polygyny and paternity, contributed to significantly higher realized reproductive success by polygynous male dickcissels.     

Widespread density-dependent seedling mortality promotes species coexistence in a highly diverse Amazonian rain forest

Negative density-dependent mortality can promote species coexistence through a spacing mechanism that prevents species from becoming too locally abundant. Negative density-dependent seedling mortality can be caused by interactions among seedlings or between seedlings and neighboring adults if the density of neighbors affects the strength of competition or facilitates the attack of natural enemies. We investigated the effects of seedling and adult neighborhoods on the survival of newly recruited seedlings for multiple cohorts of known age from 163 species in Yasuni National Park, Ecuador, an ever-wet, hyper-diverse lowland Amazonian rain forest. At local scales, we found a strong negative impact on first-year survival of conspecific seedling densities and adult abundance in multiple neighborhood sizes and a beneficial effect of a local tree neighborhood that is distantly related to the focal seedling. Once seedlings have survived their first year, they also benefit from a more phylogenetically dispersed seedling neighborhood. Across species, we did not find evidence that rare species have an advantage relative to more common species, or a community compensatory trend. These results suggest that the local biotic neighborhood is a strong influence on early seedling survival for species that range widely in their abundance and life history. These patterns in seedling survival demonstrate the role of density-dependent seedling dynamics in promoting and maintaining diversity in understory seedling assemblages. The assemblage-wide impacts of species abundance distributions may multiply with repeated cycles of recruitment and density-dependent seedling mortality and impact forest diversity or the abundance of individual species over longer time scales.     

Benthic foraminiferal distribution on the southeastern Brazilian shelf and upper slope

Foraminiferal data were obtained from 66 samples of box cores on the southeastern Brazilian upper margin (between 23.8°–25.9°S and 42.8°–46.13°W) to evaluate the benthic foraminiferal fauna distribution and its relation to some selected abiotic parameters. We focused on areas with different primary production regimes on the southern Brazilian margin, which is generally considered as an oligotrophic region. The total density (D), richness (R), mean diversity ([`(H^￠ )] \overline{{H^{\prime } }} ), average living depth (ALD _X ) and percentages of specimens of different microhabitats (epifauna, shallow infauna, intermediate infauna and deep infauna) were analyzed. The dominant species identified were Uvigerina spp., Globocassidulina subglobosa, Bulimina marginata, Adercotryma wrighti, Islandiella norcrossi, Rhizammina spp. and Brizalina sp.. We also established a set of mathematical functions for analyzing the vertical foraminiferal distribution patterns, providing a quantitative tool that allows correlating the microfaunal density distributions with abiotic factors. In general, the cores that fit with pure exponential decaying functions were related to the oligotrophic conditions prevalent on the Brazilian margin and to the flow of the Brazilian Current (BC). Different foraminiferal responses were identified in cores located in higher productivity zones, such as the northern and the southern region of the study area, where high percentages of infauna were encountered in these cores, and the functions used to fit these profiles differ appreciably from a pure exponential function, as a response of the significant living fauna in deeper layers of the sediment. One of the main factors supporting the different foraminiferal assemblage responses may be related to the differences in primary productivity of the water column and, consequently, in the estimated carbon flux to the sea floor. Nevertheless, also bottom water velocities, substrate type and water depth need to be considered.     

Multi-residue analysis of fifty pesticides in river waters and in wastewaters

Environmental Science and Pollution Research - Three sampling campaigns were performed in the Lis River (Leiria, Portugal) in February of 2018, November of 2018, and May of 2019. River water and...