Evaluation of the role of biocolonizations in the conservation state of Machu Picchu (Peru): The Sacred Rock

Indoor Nanoparticle Characterization in Construction Waste Recycling Companies over Time

Building activity is a significant source of atmospheric contamination by ultrafine dust. Cognizant of this fact, those active in the use and recycling of construction materials must be aware of the risks associated with exposure to nanoparticles (NPs) and ultra-fine particles (UFPs), as well as the associated health impacts. This work analyzed NPs and UFPs generated in a small building-material recycling company using high-resolution electron microscopes and X-ray Diffraction. A self-made passive sampler (LSPS) that can obtain particulate samples without physical and morphological changes, especially where there is a suspension of particulate material, was used in this study. A total of 96 particulate samples, using the LSPS for three months in four seasons, were collected during the study. Thus, the dry deposition of the particles, which are considered highly harmful to human health, was found in each of the four seasons of the year. It is suggested that for future research, the toxicological evaluations of the particulates in the construction industry should be investigated through the consideration of measures to control and mitigate the health risks of workers regarding exposure to NPs and UFPs.

Developments in the intensification of photo-Fenton and ozonation-based processes for the removal of contaminants of emerging concern in Ibero-American countries

Contaminants of emerging concern (CECs), such as pharmaceuticals, personal care products, pesticides, synthetic and natural hormones and industrial chemicals, are frequently released into the environment because of the inability of conventional processes in municipal wastewater treatment plants to remove them. Some examples of alternative options to remove such pollutants are photo-Fenton and ozone-based processes, which are two techniques widely studied in Ibero-American countries. In fact, this region has been responsible for delivering frequently publications and conferences on advanced oxidation processes. This work is a critical review of recent developments in the intensification of the two aforementioned advanced oxidation techniques for CECs elimination in the Ibero-American region. Specifically for the photo-Fenton process (pF), this study analyses strategies such as iron-complexation with artificial substances (e.g., oxalic acid and ethylenediamine-N,N'-disuccinic acid) and natural compounds (such as humic-like substances, orange juice or polyphenols) and hybrid processes with ultrasound. Meanwhile, for ozonation, the enhancement of CECs degradation by adding hydrogen peroxide (i.e., peroxone), ultraviolet or solar light, and combining (i.e., photolytic ozonation) with catalysts (i.e., catalytic ozonation) was reviewed. Special attention was paid to how efficient these techniques are for removing contaminants from water matrices, and any potentialities and weak points of the intensified processes.

Portable dehumidifiers as an original matrix for the study of inhalable nanoparticles in school

Good air quality is documented as a significant factor of social justice. The human health hazards associated with air pollution are not distributed equally across cities; the most vulnerable people are more exposed to ambient air as they commute to work and wait for buses or trains at the stations. Aerosols play important roles in atmosphere quality and the climate; their oxidation at the nanoscale level may possibly increase the reactivity and toxicity of atmospheric particulates. Indoor school environments are characterized by high concentrations of different airborne particulate and gaseous pollutants. The documentation of nanoparticles (NPs), ultra-fine particles (UFPs), and micron-size particle species present in indoor primary schools are an important aspect in the recognition of their influence in respirational difficulties and decreased cognitive progress in children. This work utilizes the study of condensed water, sampled with portable dehumidifiers (PD), to describe NPs and UFPs in the vapor stage of enclosed zones. The acquired extracts were analyzed by advanced electron microscopy techniques. A total of 392 NPs and 251 UFPs were examined in a set of 22 samples acquired in moderately limited or inadequately ventilated indoor areas from several schools. Noting that NPs-related disorders happen at particular places of respirational structure, identification of site-specific NPs accumulation should be anticipated in direction to better verify the corresponding human health outcomes resulting from respirable NPs.

Influence of Environment on Microbial Colonization of Historic Stone Buildings with Emphasis on Cyanobacteria

Microbial cells that produce biofilms, or patinas, on historic buildings are affected by climatic changes, mainly temperature, rainfall and air pollution, all of which will alter over future decades. This review considers the colonization of stone buildings by microorganisms and the effects that the resultant biofilms have on the degradation of the structure. Conservation scientists require a knowledge of the potential effects of microorganisms, and the subsequent growth of higher organisms such as vascular plants, in order to formulate effective control strategies. The vulnerability of various structural materials (“bioreceptivity”) and the ways in which the environmental factors of temperature, precipitation, wind-driven rain and air pollution influence microbial colonization are discussed. The photosynthetic microorganisms, algae and cyanobacteria, are acknowledged to be the primary colonizers of stone surfaces and many cyanobacterial species are able to survive climate extremes; hence special attention is paid to this group of organisms. Since cyanobacteria require only light and water to grow, can live endolithically and are able to survive most types of stress, they may become even more important as agents of stone cultural property degradation in the future.

Geochemistry of potentially hazardous elements in loess-amended mining sediment

Contaminated mining sediment may cause environmental and human health risk due to potentially hazardous elements (PHEs) leaching into groundwater, especially under very acid (pH ≤ 3) conditions. The capability of Chinese loess to immobilise and retain copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) from element contaminated mining sediment was explored by a column leaching experiment. Results showed that loess could effectively reduce Cu geomobility, and their leachate concentrations were lower than the quality standard (1.0 mg L^-1) for ground water in China. The sierozem showed strong adsorption for Zn, Cd and Pb. The geomobility of Cu, Zn, Cd and Pb were affected by pH, electrical conductivity, organic matter and carbonate content of sediment/loess-amended sediment and sierozem. The long-term leaching of PHEs in loess-amended sediment may pose a potential risk to sierozem and groundwater in the region. This study highlights the need to develop a remediation technique to minimise the concentration level of hazardous elements in the mining sediment.

The impact of air pollution on the rate of degradation of the fortress of Florianópolis Island, Brazil

The study of the prevalence of agglomerated nanoparticles (ANPs) containing potentially hazardous elements (PHEs) in the atmosphere is an emerging field of research. As such, the development of effective analytical procedures for the documentation of ANPs in air dust is vital for the evaluation of human health consequences. X-ray powder diffraction (XRD), Raman spectroscopy (RS), Mossbauer spectroscopy (MS) and advanced microscopy (AM) analyses of levels of pollutant concentration have been completed for many years in buildings worldwide. The chemical and mineralogical features of the Fortress of Nossa Senhora da Conceição de Araçatuba in the Brazilian state of Santa Catarina were utilized to catalog the geologic makeup of the structure's raw materials. Analyses of diverse categories of historical building were developed and performed to show the incidence of normal and anthropogenic compounds with PHEs. These geochemical effects and the subsequent fate and transport of nanoparticulate and colloidal (1-1000 nm) compounds in the atmosphere have remained a focus of study for many years. However, the data published in the scientific literature is nowhere near adequate to generate an exhaustive standard of the performance, fate, and transport of natural and anthropogenic ANPs in the atmosphere. Studies to date do provide a preliminary argument for the human health risk calculations from historical buildings due to ANPs. Thus, the geochemical makeup of ANPs and their position in collected nanomineral-organic accumulations may offer some insight into their source. Our ability to detect such ANPs may decrease over time due to the tendency of historical buildings to accrete sludge over the years. The occurrence of PHEs in atmospheric ANPs has not formerly been recognized on the island environment examined in this study. However, it has been shown that it presents a clear and present danger to the preservation of historical monuments.

Impact assessment of metals on soils from Machu Picchu archaeological site

Machu Picchu is an archaeological Inca sanctuary from the 15th century, located 2430 m above the sea level in the Cusco Region, Peru. In 1983, it was declared World Heritage Site by UNESCO. The surroundings and soils from the entire archaeological site are carefully preserved together with its grass parks. Due to the importance of the archaeological city and its surroundings, the Decentralized Culture Directorate of Cusco-PAN Machu Picchu decided to carry out a careful monitoring study in order to determine the ecological status of the soils. In this work, elemental and molecular characterization of 17 soils collected along the entire park was performed by means of X-ray Diffraction (XRD) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after acidic digestion assisted by microwave energy. Thanks to the combination of these analytical techniques, it was possible to obtain the mineral composition and metal concentrations of all soils from these 17 sampling points. Finally, different statistical treatments were carried out in order to confirm the ecological status of the different sampling points from Machu Picchu archaeological site concluding that soils are not impacted.

Characterization of restoration lime mortars and decay by-products in the Meditation area of Machu Picchu archaeological site

Machu Picchu citadel is the main archaeological Inca sanctuary widely known around the world, and a World Heritage Site of high cultural and natural value. For its construction a whitish granitic rock, extracted from the "Vilcapampa or Vilcabamba" batholith formation was used. During time, some of the granitic rocks from the natural stonewalls of the Meditation area of the Archaeological Park were restored. For the restoration works done in the 50s' a specific lime mortar called Clarobesa was used. After the inclusion of this joining mortar, many efflorescences are nowadays visible in the mortar itself and on the surface of the edges of the annexed rocks. To evaluate the possible impact of these salts crystallizations in the conservation state of these natural stonewalls, a multi-analytical methodology was designed and applied. With a combination of non-invasive and destructive techniques such as X-ray Diffraction, Raman microscopy, Scanning Electron Microscope coupled to an Energy Dispersive X-ray Spectrometer and ion chromatography, the mineralogical composition and the nature/concentration of the soluble salts present in the Clarobesa mortar was determined. The experimental results suggest that Clarobesa mortar is a hydraulic lime mortar. The study of salts crystallizations by Raman microscopy allowed identifying the presence of calcium sulfates with different hydration waters and also nitrates. In some samples, the concentration of sulfates was high, reaching values up to 10% w/w. Although the concentration of nitrates is not extremely high, a clear contribution of ammonium nitrates coming from the decomposition of the nearby vegetation was assessed. Since the Clarobesa mortar can be considered an important input of ions that can migrate to the joined granitic rocks, in the future, it will be recommendable to monitor possible changes in the conservation state of the joined rocks.