Air pollution plays a pivotal role in the deterioration of many materials used in buildings and cultural monuments causing an inestimable damage. This study aims to estimate the impacts of air pollution (SO2, HNO3, O3, PM10) and meteorological conditions (temperature, precipitation, relative humidity) on limestone, copper and bronze based on high resolution air quality data-base produced with AMS-MINNI modelling system over the Italian territory over the time period 2003–2010. A comparison between high resolution data (AMS-MINNI grid, 4 × 4 km) and low resolution data (EMEP grid, 50 × 50 km) has been performed. Our results pointed out that the corrosion levels for limestone, copper and bronze are decreased in Italy from 2003 to 2010 in relation to decrease of pollutant concentrations. However, some problem related to air pollution persists especially in Northern and Southern Italy. In particular, PM10 and HNO3 are considered the main responsible for limestone corrosion. Moreover, the high resolution data (AMS-MINNI) allowed the identification of risk areas that are not visible with the low resolution data (EMEP modelling system) in all considered years and, especially, in the limestone case. Consequently, high resolution air quality simulations are suitable to provide concrete benefits in providing information for national effective policy against corrosion risk for cultural heritage, also in the context of climate changes that are affecting strongly Mediterranean basin.

Correct characterization of metal speciation and reactivity is a prerequisite for the risk assessment and remedial activity management of contaminated soil. To better understand the intrinsic reactivity of Pb and Zn, nine heavily and poorly contaminated soils were investigated using the combined approaches of chemical extractions, multi-element stable isotopic dilution (ID) method, and multi-surface modelling. The ID results show that 0.1–38% of total Pb and 3–45% of total Zn in the studied soils are isotopically exchangeable after a 3-day equilibration. The intercomparison between experimental and modelling results evidences that single extraction with 0.43 M HNO3 solubilizes part of non-isotopically exchangeable fraction of Pb and Zn in the studied soils, and cannot be used as a surrogate for ID to assess labile Pb and Zn pools in soil. Both selective sequential extraction (SSE) and modelling reveal that Mn oxides are the predominant sorption surface for Pb in the studied soils; while Zn is predicted to be mainly associated with soil organic matter in the soil with low pH and Fe/Mn oxides in the soils with high pH. Multi-surface modelling can provide a reasonable prediction of Pb and Zn adsorption onto different soil constituents for the most of the studied soils. The modelling could be a promising tool to decipher the underlying mechanism that controls metal reactivity in soil, but the submodel for Mn oxides should be incorporated and the model parameters, especially for the 2-pK diffuse layer model for Mn oxides, should be updated in the further studies.

Samples of dried marine macroalgae (Fucus serratus, Palmaria palmata and Ulva lactuca) have been analysed for trace elements by a novel, non-destructive approach involving a Niton field-portable-X-ray fluorescence (FP-XRF) spectrometer configured in a low density plastics mode with thickness correction. Detection limits for a 200-s counting time ranged from <5 μg g⁻¹ for As and Pb in F. serratus and As in P. palmata to several tens of μg g⁻¹ for Cd, Sb and Sn in all species tested. Arsenic, Cu, Pb and Zn were detected by the XRF in samples collected from a protected beach (n = 18) and in samples therefrom that had been exposed to additional aqueous elements in combination (n = 72) with concentrations returned (in μg g⁻¹) ranging from 3.9 to 39.7 for As, 13.0 to 307 for Cu, 6.1 to 14.7 for Pb and 12.5 to 522 for Zn. Independent measurements of trace elements in the macroalgae by ICP-MS following nitric acid digestion revealed a direct and significant proportionality with concentrations returned by the XRF, with slopes of the XRF-ICP relationships (As = 1.0; Cu = 2.3; Pb = 2.4; Zn = 1.7) that can be used to calibrate the instrument for direct measurements. The approach shows potential for the in situ monitoring of macroalgae in coastal regions that is currently being investigated.

Here we characterized wet deposition National Atmospheric Deposition Program (NADP) species and Clean Air Status and Trends Network (CASTNET) dry deposited particle and gas species across New York over the last 2-3 decades. In addition measurements of NH3 from the Ammonia Monitoring Network (AMoN) were analyzed. In general decreasing annual trends are observed for wet deposition SO42− and NO3− species and dry deposited particle SO42−, NO3− and NH4+ as well as gas phase SO2 and HNO3 consistent with reductions in SO2 and NOx emissions. Wet deposited NH4+ however does not show consistent trends with most sites showing little trend across the region and an indication that levels at some sites maybe increasing. NH3 concentrations also appear to be increasing although the data record is only 8 years. Base cations, Ca2+ and Mg2+ show some decreases in the 1980s but concentrations are relatively uniform since the mid-1990s. Na+ and K+ show large year to year variations, by more than an order of magnitude for Na+ due to influence of marine air at a near coastal site. In general there was a balance between the sum of cations and the sum of anions earlier in the record but the tendency has been for a cation excess in the more recent 5–10 years. Understanding the deposition of reduced nitrogen species is likely to be of concern for the foreseeable future. Such data are important in understanding acidification recovery in response to emission controls.

A comparative study between conventional methods (EPA 3050B and ISO 11466.3) of metal extraction and a simple low-cost method, using aqua regia, was carried out in this work. Six elements (Mn, Cu, Zn, Pb, Ni, and Cd) were determined by flame atomic absorption spectrometry (FAAS) in a certified sample of sediment (CNS 392). Central composite design (CCD) and response surface methodology (RSM), as well as machine learning, were used to find the optimal conditions for metal extraction. The influence of the parameters—volume of nitric acid in aqua regia (v), time of extraction (t), and temperature (T)—on Mn, Cu, Zn, and Pb recoveries was investigated. The best condition for the recovery of all the metals was v = 2.5 mL of HNO₃, t = 2 h, and T = 90 °C. In comparison with the conventional methods, the aqua regia method was found to present better recovery values and lower standard deviations for all the metals studied.

A new dithiocarbamate-base resin was synthesized utilizing the reaction between carbon disulfide and immobilized amines on the fully cross-linked side of the styrene-maleicimide (SMI) copolymer. The sorption characteristics of the synthesized resin for copper, lead, nickel, zinc, and cadmium ions were investigated, using atomic adsorption spectroscopy (AAS). The sorption capacity of the resin for each metal ion was studied as a function of pH and time. The optimum pH range for sorption of the metal ions was between 4 and 6. The capacity of the resin for the metal ions decreases in the following order: Cu(II) ≈ Pb(II) > > Zn(II) > Ni(II) > Cd(II). The sorption rate of the metal ions in the resin decreases in the following order: Zn(II) > Ni(II) > Cd(II) > Pb(II) > Cu(II). The affinity of the resin for the ions was also studied using a mixture of the heavy metal ions. The capacities of the new resin, especially for copper and lead, are significantly higher than previously studied resins. Additionally, it was shown that desorption of the captured ions from the resin within 24 h can be done using 1 M nitric acid solution.

Hydrophilic carbonaceous nanoparticles (HNPs) of uniform sizes with a good degree of dispersion in water were produced from a commercial carbon black by nitric acid treatment. The surface treatment, performed at different reaction times, generates a variable number of oxygen functional groups, mainly carboxylic, which enhance the nanoparticles hydrophilicity and heavy metal adsorption capability. The HNPs were characterized by a number of analytical techniques, including FTIR spectroscopy, thermal and elemental analysis, N₂ adsorption, dynamic light scattering, and zeta-potential measurements. The acid–base properties of the functional groups on the HNPs surface were also investigated by coulometric–potentiometric titrations. Cadmium adsorption tests were carried out in stirred reactors containing colloidal aqueous suspensions of HNPs and HNPs supported over silica. The effects of several parameters, such as the cadmium concentration, the temperature, and the solution pH, were studied. Sorbents showed an appreciable cadmium adsorption capability at different temperatures and in a wide range of pH values comparable or superior to several carbon-based sorbents, indicating a feasible use in commercial units.

A standard method for the detection and isolation of microplastics is required to adequately investigate plastic ingestion by juvenile fish. Dissections of juvenile fish guts require precise handling, which can affect the processing time if sample numbers are high. To investigate the efficacy of nitric acid (HNO₃) in aiding the isolation of microplastics using whole fish, we digested juvenile glassfish, Ambassis dussumieri (Cuvier, 1828), at room temperature and at 80 °C. For a complete digestion, overnight incubation in 10 mL of 55% analytical-reagent (AR) HNO₃ was sufficient for a whole fish of 1 g at room temperature. When coupled with elevated temperature, the digestion time is shortened to a few minutes and larger fish of 3 g can be digested in 30 min. Four of the five types of plastic survived the process, with nylon being the exception. This is a shortfall to the method; however, until a better method replaces it, we still value the use of HNO₃ for its simple, inexpensive, swift and complete digestions of whole fish. Four fish species from two feeding guilds were digested using this method to validate its use. The number of plastic particles ingested did not differ between benthic and pelagic species and microplastic fibres comprised the majority of the plastic types found.

This is the first paper that describes the atmospheric sulfur dioxide (SO₂) and nitric acid (HNO₃) monitored with a good time-resolution at the summit (3776 m a.s.l.), which is located in the free troposphere, and southeastern foot (1284 m a.s.l.) of Mt. Fuji. Japan. During the summer of 2012, two analytical systems consisting mainly of a parallel-plate wet denuder and ion chromatograph operated simultaneously at both the sampling sites. All the samples collected at both the sampling sites contained detectable levels of sulfate from gas-phase SO₂ while the nitrate from gas-phase HNO₃ was detectable in 97.8% of air samples at the southeastern foot and 88.4% at the summit. The average concentrations of SO₂ and HNO₃ were, respectively, 0.061 ± 0.071 and 0.031 ± 0.020 ppbv at the summit (n = 672), and 0.347 ± 0.425 and 0.146 ± 0.070 ppbv at the southeastern foot (n = 1344) of Mt. Fuji. Both the acidic gases at the southeastern foot and the HNO₃ at the summit showed a diurnal pattern with daytime maxima and nighttime minima. Meanwhile, the SO₂ at the summit did not show a distinct shift, which indicates the SO₂ concentrations at the summit would be principally controlled by the advection of air parcel in the free troposphere.

The present study investigates the chemical composition of rainwater (RW) from a high-altitude site “Nainital” (1958 m above msl) in the central Himalaya region, to understand the influence of local, regional, and long-range transport of pollutants. A total of 55 (2 in pre-monsoon and 53 in monsoon) RW samples were collected during the study period (June–September 2012) and were analyzed for major anions and cations using an ion chromatograph. The pH of precipitation events ranged from 4.95 to 6.50 (average 5.6 ± 0.3) was observed during the monsoon period (near to the acidic), whereas during the pre-monsoon, the pH was 6.25 ± 0.49 (alkaline) over the study region; it is due the mixture of anthropogenic as well as the natural chemical constituents. The average ionic concentration (sum of measured chemical constituents) was ∼3 times higher during the pre-monsoon (986 ± 101 μeq/1) compared to that in the monsoon season (373 ± 37 μeq/1). This is mainly due to the presence of more natural aerosols in the pre-monsoon season which is also reflected in the pH of rainwater (average 6.25 ± 0.50) as well as ionic concentration. The chemical composition suggests that Ca²⁺ was the major contributor (34%) among cations, followed by Na⁺ (10%), K⁺ (8%), and Mg²⁺ (9%), whereas Cl⁻, NO₃ ⁻, and SO₄ ²⁻ contributed ∼13, 11, and 9%, respectively, among anions. The average ratio of acidic species (SO₄ ²⁻/NO₃ ⁻) is 1.56, suggesting 61 and 39% contribution of SO₄ ²⁻ and NO₃ ⁻, respectively, which is very close to the estimated contribution of H₂SO₄ (60–70%) and HNO₃ (30–40%) in the precipitation samples. Neutralization factors for Ca²⁺, Mg²⁺, and NH₄ ⁺ in RW at Nainital are 4.94, 1.21, and 0.37, respectively, indicating their crucial role in neutralization of acidic species. The non-sea-salt (NSS) contribution to total Ca²⁺, K⁺, and Mg²⁺ is estimated to be ∼98, 97, and 74%, respectively, suggesting the dominance of crustal sources for cations. In contrast, the NSS contribution to the total Cl⁻ and SO₄ ²⁻ is 16 and 69% indicating their anthropogenic origin, respectively. Principle component analysis also suggests that the first factor (i.e., natural sources, mainly dust, and sea-salts) accounts for ∼33% variance, whereas the second factor (i.e., fossil fuel and biomass burning) accounts for ∼18% variance of the measured ionic composition. The remaining contributions are attributed to the mixed emission sources and transport of pollutants from Indo-Gangetic Plain (IGP) and western parts of India. The results of the present study reveal a significant contribution of crustal and anthropogenic sources in the RW and neutralization processes in the central Himalaya.