Toxicity of nitrophenolic pollutant 4-nitroguaiacol to terrestrial plants and comparison with its non-nitro analogue guaiacol (2-methoxyphenol).

Phenols, and especially their nitrated analogues, are ubiquitous pollutants and known carcinogens which have already been linked to forest decline. Although nitrophenols have been widely recognized as harmful to different aquatic and terrestrial organisms, we could not find any literature assessing their toxicity to terrestrial plants. Maize (monocot) and sunflower (dicot) were exposed to phenolic pollutants, guaiacol (GUA) and 4-nitroguaiacol (4NG), through a hydroponics system under controlled conditions in a growth chamber.

Kinetics and product identification of water-dissolved nitroguaiacol photolysis under artificial sunlight.

Nitroguaiacols are typical constituents of biomass-burning emissions, including absorbing aerosols which contribute to climate change. Although they are also harmful to humans and plants, their atmospheric fate and lifetimes are still very speculative. Therefore, in this work, the photolysis kinetics of aqueous-phase 4-nitroguaiacol (4NG) and 5-nitroguaiacol (5NG), and the resulting photo-formed products were investigated under artificial sunlight, observing also the effect of sunlight on the absorption properties of the solutions.

Seasonality of Polyaromatic Hydrocarbons (PAHs) and Their Derivatives in PM from Ljubljana, Combustion Aerosol Source Apportionment, and Cytotoxicity of Selected Nitrated Polyaromatic Hydrocarbons (NPAHs).

Airborne particulate matter (PM) is a vector of many toxic pollutants, including polyaromatic hydrocarbons (PAHs) and their derivatives. Especially harmful is the fine fraction (PM), which penetrates deep into the lungs during inhalation and causes various diseases. Amongst PM components with toxic potential are nitrated PAHs (NPAHs), knowledge of which is still rudimentary.

Characterization of fresh PM deposits on calcareous stone surfaces: Seasonality, source apportionment and soiling potential.

Particulate matter (PM) pollution is one of the major threats to cultural heritage outdoors. It has been recently implied that organic aerosols will prevail over inorganic carbon particulates in the future, changing the main mechanisms of damage caused by poor air quality to calcareous heritage in particular. We studied fresh particulate deposits on marble and limestone surfaces exposed to urban air in sheltered and unsheltered configurations.

Direct quantification of PAHs and nitro-PAHs in atmospheric PM by thermal desorption gas chromatography with electron ionization mass spectroscopic detection.

In this work, we developed and optimized a method for the analysis of PAHs and nitro-PAHs in atmospheric particulate matter (PM) samples by using thermal desorption gas chromatography coupled with electron ionization single quadrupole mass spectrometry (TD-GC-(EI)-MS). The method uses thermal desorption from a PM on a filter sample as means of sample introduction to a column and obviates the need for complex extraction procedures, which are time-consuming and require environmentally unfriendly solvents. Moreover, the possibility of systematic errors is minimized and a significantly smaller amount of sample is required compared to traditional techniques requiring a pre-extraction step (approx.

Determination of trace concentrations of simple phenols in ambient PM samples.

Phenols are hazardous, but yet ubiquitous in the environment, including in atmospheric aerosols due to combustion emissions. There, phenols are subjected to secondary transformations, producing even more toxic nitrophenolic air pollutants. However, primary simple phenols, i.

Impact of air pollution on outdoor cultural heritage objects and decoding the role of particulate matter: a critical review.

Atmospheric gases and particulate matter (PM) in contact with the material's surface lead to chemical and physical changes, which in most cases cause degradation of the cultural heritage material. Atmospheric damage and soiling are recognized as two pivotal forms of deterioration of cultural heritage materials caused by air pollution. However, the atmospheric damage effect of PM is rather complicated; its variable composition accelerates the deterioration process.

Seasonal variability of nitroaromatic compounds in ambient aerosols: Mass size distribution, possible sources and contribution to water-soluble brown carbon light absorption.

Nitroaromatic compounds (NACs) as important constituents of atmospheric humic-like substances (HULIS) and brown carbon (BrC) affect the Earth's climate and pose a serious environmental hazard. We investigated seasonal size-segregated NACs in aerosol samples from the urban background environment in Ljubljana, Slovenia. Total concentrations of twenty NACs in PM were on average from 0.

Guaiacol Nitration in a Simulated Atmospheric Aerosol with an Emphasis on Atmospheric Nitrophenol Formation Mechanisms.

Atmospheric nitrophenols are pollutants of concern due to their toxicity and light-absorption characteristics and their low reactivity resulting in relatively long residence times in the environment. We investigate multiphase nitrophenol formation from guaiacol in a simulated atmospheric aerosol and support observations with the corresponding chemical mechanisms. The maximal secondary organic aerosol (SOA) yield (42%) is obtained under illumination at 80% relative humidity.

No more waste at the elemental analysis of airborne particulate matter on quartz fibre filters.

Particulate matter (PM) is the major environmental pollutant. Its elemental composition is routinely monitored. Inductively coupled plasma mass spectroscopy (ICPMS) is commonly applied after a PM sample has been digested by an acid during a microwave treatment.

Significant Accumulation of Iodine and Selenium in Chicory ( L. var. Hegi) Leaves after Foliar Spraying.

The interactions between the uptake of selenium (as selenite and selenate) and iodine (as iodate and iodide) by red chicory ( L. var. Hegi) and their effects on selected morphological and physiological characteristics were investigated.

Response of Pumpkin to Different Concentrations and Forms of Selenium and Iodine, and their Combinations.

The elements selenium (Se) and iodine (I) are both crucial for the normal functioning of the thyroid. Biofortification with these elements is particularly feasible in areas where they show a deficit. Iodine and selenium can have positive effects on different plants when applied at the correct concentrations.

Biofortification with selenium and iodine changes morphological properties of Brassica oleracea L. var. gongylodes) and increases their contents in tubers.

Kohlrabi (Brassica oleracea L. var. gongylodes L.

Chemical characterization of fine aerosols in respect to water-soluble ions at the eastern Middle Adriatic coast.

Fine particulate matter (PM) concentrations at the Middle Adriatic coastal site of Croatia were affected by different air-mass inflows and/or local sources and meteorological conditions, and peaked in summer. More polluted continental air-mass inflows mostly affected the area in the winter period, while southern marine pathways had higher impact in spring and summer. Chemical characterization of the water-soluble inorganic and organic ionic constituents is discussed with respect to seasonal trends, possible sources, and air-mass inputs.

OH radicals reactivity towards phenol-related pollutants in water: temperature dependence of the rate constants and novel insights into the [OH-phenol]˙ adduct formation.

Substituted phenols are known to readily react with the hydroxyl radical (OH˙), which is the most powerful atmospheric oxidant and is also most often used in advanced oxidation processes (AOP) for wastewater treatment. We report temperature-dependent (278.15-318.

Electrochemistry as a Tool for Studies of Complex Reaction Mechanisms: The Case of the Atmospheric Aqueous-Phase Aging of Catechols.

The ultimate goal in the understanding of complex chemical processes is a complete description of the underlying reaction mechanism. In the present study and for this purpose, a novel experimental platform is introduced that builds upon electrochemistry capable of generating reactive intermediate species at the electrode surface. The atmospherically relevant nitration of catechols is taken as a case example.

Kinetic and Theoretical Study of the Atmospheric Aqueous-Phase Reactions of OH Radicals with Methoxyphenolic Compounds.

Methoxyphenols, which are emitted through biomass burning, are an important species in atmospheric chemistry. In the present study, temperature-dependent aqueous-phase OH radical reactions of six methoxyphenols and two related phenols have been investigated through laser flash photolysis and the density functional theory. The rate constants obtained were in a range of (1.

Biofortification of common buckwheat microgreens and seeds with different forms of selenium and iodine.

Background: The biofortification of crops can counteract human diseases, including selenium (Se) and iodine (I) deficiencies in the diet. Little is known about the effects of combinations of Se and I on microgreens and seeds, or on their accumulation in these tissues. The present study aimed to evaluate Se (SeO , SeO ) and I (I , IO ) biofortification of common buckwheat microgreens and seeds with respect to the effects of the addition of Se, I and Se + I on yield and on physiological and biochemical characteristics.

Underappreciated and Complex Role of Nitrous Acid in Aromatic Nitration under Mild Environmental Conditions: The Case of Activated Methoxyphenols.

Many ambiguities surround the possible mechanisms of colored and toxic nitrophenols formation in natural systems. Nitration of a biologically and environmentally relevant aromatic compound, guaiacol (2-methoxyphenol), under mild aqueous-phase conditions (ambient temperatures, pH 4.5) was investigated by a temperature-dependent experimental modeling coupled to extensive ab initio calculations to obtain the activation energies of the modeled reaction pathways.

Size-Resolved Surface-Active Substances of Atmospheric Aerosol: Reconsideration of the Impact on Cloud Droplet Formation.

Our current understanding of the importance of surface-active substances (SAS) on atmospheric aerosol cloud-forming efficiency is limited, as explicit data on the content of size-resolved ambient aerosol SAS, which are responsible for lowering the surface tension (σ) of activating droplets, are not available. We report on the first data comprising seasonal variability of size-segregated SAS concentrations in ambient aerosol particulate matter (PM). To assess the impact of SAS distribution within PM on cloud droplet activation and growth, a concept of surfactant activity was adopted and a parametrization developed; i.

Nighttime Aqueous-Phase Formation of Nitrocatechols in the Atmospheric Condensed Phase.

Yellow-colored methylnitrocatechols (MNC) contribute to the total organic aerosol mass and significantly alter absorption properties of the atmosphere. To date, their formation mechanisms are still not understood. In this work, the intriguing role of HNO (catalytic and oxidative) in the dark transformation of 3-methylcatechol (3MC) under atmospherically relevant aqueous-phase conditions is emphasized.

Is foliar enrichment of pea plants with iodine and selenium appropriate for production of functional food?

Pea (Pisum sativum L.) plants were sown in a field and foliar sprayed at blooming stage with solutions of different forms of iodine (I) - I and IO and selenium (Se) - SeO and SeO. The possibility of enrichment of pea seeds to nutritionally important levels of both elements and their distribution through the plant parts were studied.

Does extensive agriculture influence the concentration of trace elements in the aquatic plant Veronica anagallis-aquatica?

The present study describes the influence of extensive agriculture on the concentrations of As, Cr, Cu, Cd, Se, Pb and Zn in sediments and in the aquatic plant Veronica anagallis-aquatica. The investigation, spanning 4 years, was conducted on three watercourses in Slovenia (Pšata, Lipsenjščica and Žerovniščica) flowing through agricultural areas. The different sampling sites were chosen on the basis of the presence of different activities in these regions: dairy farming, stock raising and extensive agriculture.

Seed soaking in I and Se solutions increases concentrations of both elements and changes morphological and some physiological parameters of pea sprouts.

Pea (Pisum sativum L., cv. 'Petit Provencal') seeds were soaked in solutions of different iodine (I) and selenium (Se) forms (1000 mg I L and 10 mg Se L).

Acute toxicity of emerging atmospheric pollutants from wood lignin due to biomass burning.

Guaiacol (2-methoxyphenol) is an important atmospheric pollutant. It is the major component of wood lignin and is essentially emitted to the atmosphere during biomass burning. Its aging in the tropospheric aqueous phase leads to the generation of the following ring-retaining transformation products, also during nighttime: 4-nitroguaiacol, 6-nitroguaiacol, and dinitroguaiacol.