As an emerging brominated flame retardant (BFR), tetrabromobisphenol S (TBBPS) has been frequently detected in the environmental media and organisms. Knowledges on the transformation and fate of TBBPS in both environment and engineering systems are essential to its ecological risk assessment. Herein, we reported the photochemical decomposition of TBBPS in aqueous solution upon 254 nm ultraviolet irradiation (UV₂₅₄). Results show that TBBPS was highly photoreactive, most likely due to the presence of four ortho-bromine substituents. The molar absorption coefficient and quantum yield of TBBPS were found to be pH-dependent, with the monoanionic form being most photoreactive. A series of photoproducts were identified by solid phase extraction (SPE) combined with liquid chromatography-electrospray ionization-triple quadrupole mass spectrometry (LC-ESI(+)-MS/MS. The photolysis of TBBPS likely proceeded through photonucleophilic substitution, photoreductive debromination, and β-scission reactions. A ketocarbene, possibly derived from the lower lying excited triplet state, was proposed to be involved in the photolysis of TBBPS. Ion chromatography analysis revealed that debromination occurred quickly, and the yield of bromide (Br⁻) approached 100% after 90 min irradiation. The presence of SRNOM and MRNOM inhibited the photodegradation rate of TBBPS, which is likely due to the light-screening and physical quenching effects of natural organic matter (NOM). Our results reveal that photolysis is an important process for the attenuation of TBBPS in aquatic system; however, naturally occurring species such as NOM can appreciably retard the decay of TBBPS.

Allergic diseases have been one of the leading causes of chronic disorders in the United States. Animal studies have suggested that exposures to perchlorate, nitrate, and thiocyanate could induce allergic inflammation. However, the associations have not been examined among general populations. Here, we investigated data of 7030 participants aged ≥6 years from the National Health and Nutritional Examination Survey (NHANES) 2005–2006. Urinary levels of perchlorate, nitrate, and thiocyanate were measured by ion chromatography combined with electrospray tandem mass spectrometry. Information on allergic symptoms (hay fever, allergy, rash, sneeze, wheeze, eczema, and current asthma) was collected by questionnaire. Allergic sensitization was defined by a concentration ≥150 kU/L for total immunoglobulin E (IgE) levels. The associations were estimated using multivariate-adjusted logistic regression models. A positive association was observed for urinary nitrate and eczema (p < 0.001 for the trend). Compared with quartile 1 (lowest quartile), the odds ratios of eczema with 95% confidence intervals [ORs (95% CIs)] from quartiles 2 to 4 were 1.72 (95% CI, 1.41, 2.09), 1.94 (1.53, 2.47) and 2.10 (1.49, 2.97) for urinary nitrate. In addition, urinary thiocyanate was positively related to sneeze (ORQ₄ ᵥₛ. Q₁: 1.25, 95% CI: 1.01, 1.55; p = 0.015 for the trend). However, urinary perchlorate was not correlated with any allergic-related outcome. Additionally, the associations were different among subgroups in a four-level polytomous model. Thus, our results suggested that exposures to nitrate and thiocyanate may be associated with allergic symptoms. Further investigations are warranted to concentrate on the practical strategies to monitor exposure levels and the latent mechanisms of the relationship between exposure and allergy.

From December 1993 to January 1995 and from October 2009 to October 2010, a total of 320 and 365 daily samples of the PM2.5 were collected at a rural background site (National Atmospheric Observatory Košetice) in Central Europe. The PM2.5 samples were analyzed for 29 and 26 elements respectively by Particle-Induced X-ray Emission (PIXE) and water-soluble inorganic ions by Ion Chromatography (IC) in 2009/2010. The Positive Matrix Factorization (PMF) was applied to the chemical composition of PM2.5 to determine its sources. The decreasing trends of almost all elements concentrations, especially the metals regulated by the EU Directive (2004/107/EC) are evident. The annual median ratios indicate a decrease in concentrations of the PM2.5 elements. The slight increase of K concentrations and Spearman's rank correlation coefficient rs 0.09 K/Se points to a rise in residential wood combustion. The S concentrations are nearly comparable (higher mean in 2009/2010, while the annual median ratio is under 1). The five major source types in the mid-1990s were ascribed to brown coal combustion, oil combustion, sea salt and dust – long-range transport, re-suspended dust and black coal combustion. The industrial combustion of brown and/or black coal (rs 0.75 Se/As, rs 0.57 Ga/Ge and rs 0.20 As/Zn) and oil (rs 0.72 V/Ni) of the regional origin dominated. In the 1990s, the potential source regions were the border area of Czech Republic, German and Poland (brown coal), the Moravia-Silesia region at the Czech-Polish border (black coal), and Slovakia, Austria, Hungary, and the Balkans (oil). In 2009/2010, the apportioned sources were sulfate, residential heating, nitrate, industry, re-suspended dust, and sea salt and dust – long-range transport. The secondary sulfate from coal combustion and residential biomass burning (rs 0.96, K/K+) of local origin dominated.The declining trend of the elemental concentrations and change in the source pattern of the regional background PM2.5 in Central Europe between the mid-1990s and 2009/10 reflects the economic transformation and impact of stricter legislation in Central Europe.

Hourly concentrations of water-soluble inorganic ions (Na⁺, NH₄⁺, K⁺, Mg²⁺, Ca²⁺, Cl⁻, NO₃⁻ and SO₄²⁻) in PM₂.₅ and related reactive gases were measured with a Gas and Aerosol Collector combined with Ion Chromatography (GAC-IC) in urban Chengdu from April 17 to May 27, 2017, during which both haze and dust episodes occurred frequently. Nitrate was the most abundant ion in PM₂.₅ and substantially increased during haze pollution with the NO₃⁻/SO₄²⁻ mass ratio increasing from 0.78 during clean period to 1.1 during haze period. Aerosols in Chengdu were generally ammonium-rich, wherein ammonium nitrate was primarily formed through homogeneous gas-phase reactions and limited by the availability of HNO₃, indicating that preferentially reducing the emissions of NOx could make for mitigating spring haze pollution in Chengdu. Backward trajectory clustering coupled with measured species and a potential source contribution function (PSCF) for PM₂.₅, PM₁₀/PM₂.₅, sulfate, nitrate, ammonium, and Ca²⁺ indicated that regionally transported pollutants from the southern and southeastern Sichuan Basin strongly contributed to springtime PM₂.₅ pollution in Chengdu, but long-distance transport from northwestern China also contributed to dust pollution. Moreover, the treatment of urban fugitive dust in southern Sichuan is also important for reducing coarse particles in Chengdu. Therefore, the improvement of air quality in Chengdu, even in the Sichuan Basin, requires the regional joint emission reduction of particles and gaseous precursors across the entire Sichuan Basin, especially for cities located in southeastern Sichuan Basin.

The aim of this study was to provide urinary levels of total arsenic (TAs) and As species as arsenobetaine (AsB), arsenocholine (AsC), inorganic As (i.e., [As(III)+As(V)]), methylarsonic acid (MMA) and dimethylarsinic acid (DMA) in 7 year-old-children (n = 200) enrolled in the Northern Adriatic Cohort II (NACII), a prospective cohort in a coastal area of Northeast Italy. TAs was determined by sector field-inductively coupled plasma mass spectrometry (SF-ICP-MS) and AsB, AsC, As(III), As(V), MMA and DMA by ion chromatography coupled to ICP-MS (IC-ICP-MS). The geometric mean (GM) for TAs was 12.9 μg/L and for [iAs + MMA + DMA] was 4.26 μg/L. The species AsB (GM of 5.09 μg/L) and DMA (GM of 3.20 μg/L) had the greatest percentage contribution to TAs levels; a greater percentage contribution from AsB is seen at TAs >10 μg/L and from DMA at TAs <10 μg/L. Urinary [iAs + MMA] levels were positively associated with [iAs + MMA + DMA] and DMA with AsB levels. Fish, shellfish and crustaceans consumption increased the AsB and TAs levels, while rice intake, mothers’ education level and selenium (Se) concentration influenced the DMA concentration. Children have a high capacity to metabolize and detoxify the iAs because of the higher secondary methylation index (ratio DMA/MMA) with respect to primary methylation index (ratio MMA/iAs). In addition, the median level of [iAs + MMA + DMA] in the whole population of children was lower than the Biomonitoring Equivalent (BE) value for non-cancer endpoints. Also the Margin of Safety (MOS) value based on the population median was greater than 1, thus the exposure to the toxicologically relevant As species was not likely to be of concern.

We studied the size distribution of ions (Cl⁻, NO₃⁻, SO₄⁼, Na⁺, NH₄⁺, K⁺, Mg⁺⁺, Ca⁺⁺) and elements (As, Ba, Cd, Co, Cs, Cu, Fe, Li, Mn, Ni, Pb, Rb, Sb, Se, Sn, Sr, Ti, Tl, V, Zn) during the winter and summer seasons of seven consecutive years (2008–2014) in an area of the Po Valley (Northern Italy) characterised by industrial, agricultural and urban settings. The study included the collection and analysis of 41 series of size-segregated samples (MOUDI sampler, 10 stages, cut sizes from 0.18 to 18 μm). Ions were analysed by ion chromatography; elemental analysis was carried out by ICP-MS, by applying a chemical fractionation method able to increase the selectivity of PM source tracers.Our results indicate that important winter/summer variations occurred in both the concentration and size distribution of most PM components. These variations were explained in terms of variations in the strength of the prevailing sources of each component.The contribution of biomass burning for domestic heating was highlighted by the well-known tracer K⁺ but also by the soluble fraction of Rb, Cs and Li. Biomass burning contribution to atmospheric PM was mostly contained in the fine fraction, with a broad size-distribution from 0.18 to 1.8 μm. This source also appreciably increased the concentration of other elements in fine PM (As, Cd, Co, Mn, Pb, Sb, Sn).A few PM components (tracers of sea-spray, brake lining and some industries) did not show marked seasonal variations in concentration and size distribution. However, during winter, for brake lining and industry tracers we observed an upward shift in the dimension of fine particles and a downward shift in the dimension of coarse particles, due to the ageing of the air masses.

This study investigated the factors that regulated the degradation of perfluorooctanoic acid (PFOA) in laccase-catalyzed oxidative humification reactions with 1-hydroxybenzotriazole (HBT) as a mediator. The reaction rates were examined under conditions with key factors varied, including initial PFOA concentrations, laccase and HBT dosages, and the ionic contents of the reaction solutions. The PFOA degradation followed pseudo-first order kinetics, and the rate constants (k) were similar for the high (100 μmol L⁻¹) and low (1.00 μmol L⁻¹) initial PFOA concentrations, respectively at 0.0040 day⁻¹ (r² = 0.98) and 0.0042 day⁻¹ (r² = 0.86) under an optimum reaction condition tested in this study. The metal ions contained in the reaction solution appeared to have a strong impact on PFOA degradation. Differential UV-Vis spectrometry revealed that Cu²⁺ can complex with PFOA, which plays an essential role to enable PFOA degradation, probably by bridging the negatively charged PFOA and laccase, so that the free radicals of HBT that are released from laccase can reach and react with PFOA. It was also found that Fe³⁺ plays a similar role as Cu²⁺ to enable PFOA degradation in the laccase-HBT reaction system. In contrast, Mg²⁺ and Mn²⁺ cannot complex with PFOA under the investigated conditions, and do not enable PFOA degradation in the laccase-HBT system. Fluoride and partially fluorinated compounds were detected as PFOA degradation products using ion chromatography and high resolution mass spectrometry. The structures of the products suggest the reaction pathways involving free-radical initiated decarboxylation, rearrangement, and cross-coupling.

Aim of this study was to determine by Ion Chromatography ions (Na+, Ca++, Mg++, NH4+, Cl−, Br−, SO42−, NO3−, PO43−) in honeys (honeydew and floral nectar honeys) from different Italian Regions and from countries of the Western Balkan area. The compositional data were processed by multivariate analysis (PCA and HCA). Arboreal honeydew honeys from the Western Balkans had higher concentrations (from two to three times) of some environmental pollutants (Br−, SO42− and PO43− contents), due to industrial and agricultural activities, than those from Italian regions. The cationic profiles were very similar in both groups. Multivariate analysis indicated a clear difference between nectar honeys and arboreal/honeydew honeys (recognition of the botanical origin). These findings point to the potential of ionic constituents of honey as indicators of environmental pollution, botanical origin and authenticity.

This study determined the effect of monsoonal changes on the composition of atmospheric surfactants in coastal areas. The composition of anions (SO42−, NO3−, Cl−, F−) and the major elements (Ca, K, Mg, Na) in aerosols were used to determine the possible sources of surfactants. Surfactant compositions were determined using a colorimetric method as methylene blue active substances (MBAS) and disulphine blue active substances (DBAS). The anion and major element compositions of the aerosol samples were determined by ion chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. The results indicated that the concentrations of surfactant in aerosols were dominated by MBAS (34–326pmolm−3). Monsoonal changes were found to significantly affect the concentration of surfactants. Using principal component analysis-multiple linear regressions (PCA-MLR), major possible sources for surfactants in the aerosols were motor vehicle emissions, secondary aerosol and the combustion of biomass along with marine aerosol.

The size distribution of water-soluble inorganic components of urban aerosols in Shanghai was studied. The size-resolved aerosol samples collected by an 8-stage cascade sampler between April and May of 2012 were analyzed by ion chromatography. The ion mass concentrations followed the sequence of SO42−>NO3−~NH4+>Ca2+>Na+ ~Cl−>K+>Mg2+>F− for each size fraction below 2.1μm, while the sequence was NO3−>SO4−2>Ca2+>NH4+>Na+>Cl−>K+>Mg2+>F− for coarse mode particles larger than 3.3μm. The size distribution in 5 fractions showed that SO42−, NO3−, and NH4+ were generally in the fine mode peaking below 1μm while Ca2+, Mg2+, Na+, and Cl− were bimodally distributed with a second peak larger than 2.1μm. Back trajectory analyses revealed that the air masses could be classified into three main groups. The total ion concentrations were comparable between the terrestrial and mixing regimes. In the terrestrial regime, fine mode sulfate and nitrate were predominantly associated with ammonium. The excessive sulfate and nitrate over the whole size range might exist in the forms of Ca(NO3)2 and CaSO4. In the maritime regime, the decrease in SO42−, NO3−, and NH4+ contributed to the improvement in air quality. Besides marine aerosols, local emissions from soil dust and coal combustion were also important sources of sea-salt type ions (i.e., Na+ and Cl−).