Reaction Of Ozone Research Articles

Can ozone mass transfer in water treatment be enhanced through independent pressurized ozonation?

The dissolved ozone equilibrium concentration is hard to improve by increasing the gas phase partial pressure due to the low initial pressure and difficulty in pressurization. In this study, a novel hydraulic pressurization technology was developed to reliably elevate the ozonation pressure and improve the solubility of ozone. It was located downstream of the ozone generator to avoid generator overpressure. Specifically, at the optimal pressure of 0.30 MPa with an initial ozone flow rate of 1–6 L min−1, the specific surface area of bubbles and turbulent dissipation rate in the ozonation reactor were up to 2.5- and 1.5-fold that of the atmospheric aeration. Meanwhile, the dissolved ozone equilibrium concentration, redox potential, and volumetric mass transfer coefficient were up to 2.4-, 1.6-, and 2.7-fold that of atmospheric aeration, respectively. The increase in bubble-specific surface area and turbulent dissipation rate, synergistically enhanced the mass transfer, contributing 83.2–94.4 % and 5.6–16.8 %, respectively. As the reactor pressure was increased from 0 to 0.30 MPa, the decolorization time of Acid Red 18 was shortened from 20 to 8 min, and the COD removal rate increased from 48.0 % to 85.0 %. This work provides an alternative approach coupled with a novel device that enhances the ozone mass transfer during water treatment.

Infrared Matrix-Isolation and Theoretical Studies of the Reactions of Bis(benzene)chromium with Ozone.

Reactions of bis(benzene)chromium (Bz2Cr) and ozone (O3) were studied using low-temperature argon matrix-isolation infrared spectroscopy with supporting DFT calculations. When Bz2Cr and O3 were co-deposited, they reacted upon matrix deposition to produce two new prominent peaks in the infrared spectrum at 431 cm-1 and 792 cm-1. These peaks increased upon annealing the matrix to 35 K and decreased upon UV irradiation at λ = 254 nm. The oxygen-18 and mixed oxygen-16,18 isotopic shift pattern of the peak at 792 cm-1 is consistent with the antisymmetric stretch of a symmetric ozonide species. DFT calculations of many possible ozonide products of this reaction were made. The formation of a hydrogen ozonide (H2O3) best fits the original peaks and the oxygen-18 isotope shift pattern. Energy considerations lead to the conclusion that the chromium-containing product of this reaction is the coupled product benzene-chromium-biphenyl-chromium-benzene (BzCrBPCrBz). 2Bz2Cr+O3→H2O3+BzCrBPCrBz, ∆Ecalc=-52.13kcal/mol.

Feasibility of intimately coupled CaO-catalytic-ozonation and bio-contact oxidation reactor for heavy metal and color removal and deep mineralization of refractory organics in actual coking wastewater

Considering the challenges for both single and traditional two-stage treatments, advanced oxidation and biodegradation, in the treatment of actual coking wastewater, an intimately coupled catalytic ozonation and biodegradation (ICOB) reactor was developed. In this study, ICOB treatment significantly enhanced the removal of Cu2+, Fe3+, and color by 39 %, 45 %, and 52 %, respectively, outperforming biodegradation. Catalytic ozonation effectively breaking down unsaturated organic substances and high-molecular-weight dissolved organic matter into smaller, more biodegradable molecules. Compared with biodegradation, the ICOB system significantly increased the abundances of Pseudomonas, Sphingopyxis, and Brevundimonas by ∼ 96 %, ∼67 %, and ∼ 85 %, respectively. These microorganisms, possessing genes for degrading phenol, aromatic compounds, polycyclic aromatics, and sulfur metabolism, further enhanced the mineralization of intermediates. Consequently, the ICOB system outperformed biodegradation and catalytic ozonation treatments, exhibiting chemical oxygen demand removal rate of ∼ 58 % and toxicity reduction of ∼ 47 %. Overall, the ICOB treatment showcases promise for practical engineering applications in coking wastewater treatment.

In vitro assessment of acute airway effects from real-life mixtures of ozone-initiated oxidation products of limonene and printer exhaust

In indoor air the reaction of ozone (O3) with terpenes may lead to the formation of irritating gas-phase products which may induce acute airway effects (i.e. sudden, short-term changes or symptoms related to the respiratory system). We aimed to perform an in vitro study on possible health effects of products from the O3-initiated reaction of limonene with printer exhaust, representing real-life mixtures in offices. Human bronchial epithelial cells were exposed for 1 hour (h) to limonene and O3, combined with printer exhaust. The resulting concentrations represented 34% and 6% of the generated initial concentrations of limonene (400 µg/m³) and O3 (417 µg/cm³), respectively, which were in range of high end realistic indoor concentrations. We observed that the reaction of limonene with O3 generated an increase of ultrafine particles within 1 h, with a significant increase of secondary reaction products 4-oxopentanal and 3-isopropenyl-6-oxo-heptanal at high end indoor air levels. Simultaneous printing activity caused the additional release of micron-sized particles and a further increase in reaction products. Relevant cellular endpoints to evaluate the possible induction of acute airway effects were measured. However, none of the test atmospheres representing office air was observed to induce these effects.

Revealing the structural variation and degradation mechanism of cellulose during ozone oxidation treatment

Despite numerous studies on the use of ozone for the removal of non-cellulosic substances from lignocellulosic fibers, the mechanism underlying cellulose degradation and the oxidized group formation during ozone oxidation treatment remain unclear. This study focuses on the extraction of α-cellulose from flax fibers. The effect of ozone oxidation on the degree of polymerization (DP) and oxidized groups in α-cellulose under different operational conditions (ozone concentration, oxidation time, water pick-up value, initial pH value) were thoroughly investigated. Additionally, the quality of α-cellulose oxidized under different phases (gas and liquid) of ozone reaction was systematically compared. Results showed that the DP value of α-cellulose-O3-Gas-80% (130 mg·L−1·min−1, 15 min, WPV 80%, pH 2.0) was lower than that of α-cellulose-O3-Liquid (130 mg·L−1·min−1, 15 min, 1:30 g·mL−1, pH 2.0) and α-cellulose-O3-Gas-0% (130 mg·L−1·min−1, 15 min). However, the carboxyl and carbonyl contents showed the opposite trends. FTIR results showed a new peak (carboxyl peak) for α-cellulose and a reduction of hydrogen bonding interactions in molecules after ozone oxidation. In addition, the crystallinity and thermal stability of α-cellulose decreased after ozone oxidation, with α-cellulose-O3-Gas-80% exhibiting the most significant decline. SEM analysis showed that the morphology of α-cellulose was changed after ozone oxidation. This study provides some guidance to mitigate ineffective degradation of cellulose and assist in the selection of cellulose protectors during the process of extracting lignocellulosic fibers by ozone oxidation.

Nanocluster Aerosols from Ozone-Human Chemistry Are Dominated by Squalene-Ozone Reactions.

Nanocluster aerosols (NCAs, <3 nm particles) are associated with climate feedbacks and potentially with human health. Our recent study revealed NCA formation owing to the reaction of ozone with human surfaces. However, the underlying mechanisms driving NCA emissions remain unexplored. Squalene is the most abundant compound in human skin lipids that reacts with ozone, followed by unsaturated fatty acids. This study aims to examine the contribution of the squalene-ozone reaction to NCA formation and the influence of ozone and ammonia (NH3) levels. In a climate-controlled chamber, we painted squalene and 6-hexadecenoic acid (C16:1n6) on glass plates to facilitate their reactions with ozone. The squalene-ozone reaction was further investigated at different ozone levels (15 and 90 ppb) and NH3 levels (0 and 375 ppb). The results demonstrate that the ozonolysis of human skin lipid compounds contributes to NCA formation. With a typical squalene-C16:1n6 ratio found in human skin lipids (4:1), squalene generated 40 times more NCAs than did C16:1n6 and, thus, dominated NCA formation. More NCAs were generated with increased ozone levels, whereas increased NH3 levels were associated with the stronger generation of larger NCAs but fewer of the smallest ones. This study experimentally confirms that NCAs are primarily formed from squalene-ozone reactions in ozone-human chemistry.

Synergistic Effects of Ozone Reaction Products and Fine Particulate Matter on Respiratory Pathophysiology in Children with Asthma

Synergistic Effects of Ozone Reaction Products and Fine Particulate Matter on Respiratory Pathophysiology in Children with Asthma

Achieving realistic ozonation conditions with synthetic water matrices comprising low-molecular-weight scavenger compounds

Ozonation is used worldwide for drinking water disinfection and increasingly also for micropollutant abatement from wastewater. Identification of transformation products formed during the ozonation of micropollutants is challenging due to several factors including (i) the reactions of both oxidants, ozone and hydroxyl radicals with the micropollutants, as well as with intermediate transformation products, (ii) effects of the water matrix on the ozone and hydroxyl radical chemistry and (iii) the generation of oxidation by-products. In this study, a simple approach to achieve realistic ozonation conditions in the absence of dissolved organic matter has been developed. It is based on composing synthetic water matrices with low-molecular-weight scavenger compounds (phenol, methanol, acetate, and carbonate) that mimic the chemical interactions of ozone and hydroxyl radicals with real water matrices. Synthetic waters composed of only four low-molecular-weight compounds successfully replicated two lake waters and two secondary wastewater effluents, matching instantaneous ozone demand, ozone and hydroxyl radical exposures in the initial phase, as well as the ozone evolution in the second phase of the ozonation process. The synthetic water matrices also reproduced the effects of temperature and pH changes observed in real waters. The abatement of two micropollutants, bezafibrate and atrazine, and the formation of the corresponding transformation products during ozonation were in agreement for synthetic and real waters. Furthermore, the kinetics and extent of bromate formation during ozonation in synthetic water were comparable to real lake water and wastewater. This supports the robustness of the proposed approach because bromate formation is very sensitive to the interplay of ozone and hydroxyl radicals. Furthermore, with the novel reaction system, a significant effect of hydroxyl radicals scavenging by carbonate on bromate formation was demonstrated. Overall, the herein-developed approach based on synthetic water matrices allows to perform realistic ozonation studies including both oxidants, ozone and hydroxyl radicals, without the constraints of using dissolved organic matter.

Self-enhanced oxidation of resistant monocyclic aromatic compounds during ozone treatment: Applicability in groundwater remediation

The Peroxone process—which utilizes a combination of ozone and hydrogen peroxide to generate hydroxyl radicals—is frequently used in groundwater remediation to effectively remove ozone-resistant contaminants. However, some monocyclic aromatic compounds with low ozone reactivity have been found to be removed by ozone solely (without the need for hydrogen peroxide) through a self-enhanced mechanism. This self-enhanced removal occurs when the interaction of ozone with hydroxide ion generates sufficient amount of hydroxyl radicals, initiating a radical reaction that subsequently propagates through the degradation intermediates. This study leverages the self-enhanced degradation mechanism for the treatment of ozone-resistant compounds during groundwater remediation. Key environmental conditions, including water alkalinity and contaminant concentration, were investigated for their effect on the self-enhanced degradation of para-chloro benzoic acid (pCBA), which served as a model for ozone-resistant compounds. High pCBA removal was observed during ozonation in the concentration range of 0.5–5 μM, where the decay kinetics of pCBA and ozone significantly dependent on the initial pCBA concentration. Furthermore, decreased pCBA removal was noted in water matrices with increased alkalinity, largely due to the scavenging of OH radicals by carbonate species. Finally, pCBA removal was investigated in natural groundwater, where co-existing substances acted as ozone/radical scavengers, leading to reduced pCBA removal. Overall, this study highlights the importance of the self-enhanced removal mechanism of monocyclic aromatic contaminants when treating water with high contamination levels and low-to-moderate alkalinities.

Mimicking Ozonolysis via Mechanochemistry: Internal Alkynes to 1,2-Diketones using H5IO6.

Utilizing periodic acid as an environmentally benign oxidizing agent, this study introduces a novel mechanochemical method that mimics ozonolysis to convert internal alkynes into 1,2-diketones, showcasing effective emulation of ozone's reactivity. Notably, this oxidation occurs at room temperature in aerobic conditions, eliminating the need for toxic transition metals, hazardous oxidants, or expensive solvents. Through control experiments validating the mechanism, substantial evidence supports a concerted reaction pathway. This progress marks a significant stride toward cleaner and more efficient chemical synthesis, mitigating the environmental impact of conventional processes. Assessing the green chemistry metrics in both solvent-free and previously reported solvent-based methods, our eco-friendly protocol demonstrates an E-factor of 7.40, a 51.7 % atom economy, a 45.5 % atom efficiency, 100 % carbon efficiency, and 11.9 % reaction mass efficiency when solvents are not used.

How Does Personal Hygiene Influence Indoor Air Quality?

Humans are known to be a continuous and potent indoor source of volatile organic compounds (VOCs). However, little is known about how personal hygiene, in terms of showering frequency, can influence these emissions and their impact on indoor air chemistry involving ozone. In this study, we characterized the VOC composition of the air in a controlled climate chamber (22.5 m3 with an air change rate at 3.2 h-1) occupied by four male volunteers on successive days under ozone-free (∼0 ppb) and ozone-present (37-40 ppb) conditions. The volunteers either showered the evening prior to the experiments or skipped showering for 24 and 48 h. Reduced shower frequency increased human emissions of gas-phase carboxylic acids, possibly originating from skin bacteria. With ozone present, increasing the number of no-shower days enhanced ozone-skin surface reactions, yielding higher levels of oxidation products. Wearing the same clothing over several days reduced the level of compounds generated from clothing-ozone reactions. When skin lotion was applied, the yield of the skin ozonolysis products decreased, while other compounds increased due to ozone reactions with lotion ingredients. These findings help determine the degree to which personal hygiene choices affect the indoor air composition and indoor air exposures.

Biopolymer-derived structured graphitic carbons as metal-free heterogeneous ozonation catalysts in water

The development of metal-free heterogeneous catalysts for advanced oxidation processes is an important area of research, advancing in sustainability, with potential practical applications in water treatment. In this work, we report the development of defective structured graphitic carbons synthesized from biomass including alginate or chitosan polysaccharides and used as metal-free ozonation catalysts in water. These solids were characterized by several techniques, including powder X-ray diffraction, several spectroscopies (i.e. X-ray photoelectron, Raman or Fourier Transform infrared), elemental combustion analyses, thermogravimetric measurements, and electron microscopic techniques. The catalytic performance of graphitic carbon was examined in the ozonation reaction and the graphitic carbon derived from alginate (G) was found to be the most active catalyst by showing complete degradation in less than 4 h under the operational conditions as oxalic acid (50 mg L−1), catalyst (100 mg L−1), 20 °C, O3 dosage (140 mg h−1) at pH 3. Importantly, this solid retains its activity mostly upon reuse for more than 20 h, an observation that compares favorably with previous reports using graphene-based materials. In addition, activity of partially deactivated catalyst can be recovered by a pyrolysis process associated to the reconstitution of graphitic active sites of the catalyst. Experimental evidence by electron spin resonance together with specific (photo)catalytic experiments is provided to support the role of 1O2 as key intermediate during the oxalic acid degradation in water in the presence of G. This study exemplifies the activity of active graphitic-based solids from biomass precursors as ozonation heterogeneous catalysts in water in the absence of any metal.

Extraction of homogeneous lignin oligomers by ozonation of Miscanthus giganteus and vine shoots in a pilot scale reactor

Lignin, a complex phenolic polymer crucial for plant structure, is mostly used as fuel but it can be harnessed for environmentally friendly applications. This article explores ozonation as a green method for lignin extraction from lignocellulosic biomass, aiming to uncover the benefits of the extracted lignin. A pilot-scale ozonation reactor was employed to extract lignin from Miscanthus giganteus (a grass variety) and vine shoots (a woody biomass). The study examined the lignin extraction and modification of the fractions and identified the generation of phenolic and organic acids. About 48 % of lignin was successfully extracted from both biomass types. Phenolic monomers were produced, vine shoots yielding fewer monomers than Miscanthus giganteus. Ozonation generated homogeneous lignin oligomers, although their molecular weight decreased during ozonation, with vine shoot oligomers exhibiting greater resistance to ozone. Extracted fractions were stable at 200 °C, despite the low molecular weight, outlining the potential of these phenolic fractions.

Research on development and quantitative control preparation technology of array-type microfine bubbles generator

In traditional wastewater treatment, ozone injection efficiency is low. There is a need for the quantitative preparation of ozone-based microfine bubbles to balance bubble stability and ozone reactivity. To address this, we developed coaxial and T-type ozone-based microfine bubble generators and conducted experiments to compare their bubble production effects. The more effective generator was then compared with the traditional aeration method. The results indicate the following: 1. The coaxial type is more effective in producing ozone-based microfine bubbles. 2. The bubbles produced by the coaxial type have an average diameter of 0.2–0.4 mm and a residence time of ∼2 min, meeting microfine bubble standards. Experimental data analysis shows compliance with the force process and bubble growth mechanism under coaxial flow, meeting the requirements for quantitative and controllable ozone-based microfine bubble production. 3. Ozone bubbles from the coaxial method surpass those from traditional aeration in volume and concentration. More than 99.73% are microfine bubbles, with an ozone concentration of ∼84.5%. 4. The coaxial method more effectively reduces COD values in water, contributing to efficient wastewater treatment. This research presents new avenues for efficient sewage treatment.

WITHDRAWN: An Investigation of a Hybrid Solar-Mineral Disinfection Technique Using Zeolite and Dead Sea Clay

Effluents from water treatment plants (WTP) can often contain a complex mixture of residual micro-contaminants and organisms, not removed during wastewater treatment. A combined trickling filter, activated sludge treatment, ozonation, membrane filtration, and suspended biofilm reactors have been shown to reduce these contaminants in waste effluent but at high capita cost. This study examined an inexpensive method of purifying water, which combines solar water disinfection with natural mineral clays (SOMIN-DIS). The study involved the addition of two types of mineral clays, Zeolite and Dead Sea minerals, to containers of polluted wastewater, at varying concentrations. The containers were then subjected to different durations of sunlight exposure. Then, samples were taken from all of the containers to quantify the overall numbers of Total Coliform, Pseudomonas aeruginosa (P.aeruginosa), and Escherichia coli (E.coli), utilizing the IDEXX system. The findings indicated that incorporating Dead Sea clay and Zeolite into SODIS-treated wastewater decreased the overall number of harmful microorganisms and shortened the disinfection duration, as compared to using natural minerals and solar water disinfection (SODIS) independently. Additionally, the study determined that the most effective concentration of Dead Sea minerals, resulting in the least amounts of harmful microorganisms and shortest purification duration, was 0.001g/ml. In contrast, the optimum concentration of Zeolite was 0.002g/ml. In general, the addition of Dead Sea and Zeolite minerals to the wastewater increased the inactivation of bacteria under SODIS from 40% to 65%.

Preparation of CeO2 Supported on Graphite Catalyst and Its Catalytic Performance for Diethyl Phthalate Degradation during Ozonation

Catalysts for the efficient catalytic decomposition of ozone to generate reactive free radicals to oxidize pollutants are needed. The graphite-supported CeO2 catalyst was optimally prepared, and its activity in ozonation was evaluated using the degradation of diethyl phthalate (DEP) as an index. The stability of CeO2/graphite catalyst and the influence of operating conditions on its catalytic activity were investigated, and the mechanism of CeO2/graphite catalytic ozonation was analyzed. CeO2/graphite had the highest catalytic activity at a Ce load of 3.5% and a pyrolysis temperature of 400 °C with the DEP degradation efficiency of 75.0% and the total organic carbon (TOC) removal efficiency of 48.3%. No dissolution of active components was found during the repeated use of CeO2/graphite catalyst. The ozone dosage, catalyst dosage, initial pH, and reaction temperature have positive effects on the DEP degradation by CeO2/graphite catalytic ozonation. The presence of tert-butanol significantly inhibits the degradation of DEP at an initial pH of 3.0, 5.8, or 9.0, and the experimental results of the •OH probe compound pCBA indicate that the CeO2/graphite catalyst can efficiently convert ozone into •OH in solution. The DEP degradation in the CeO2/graphite catalytic ozonation mainly depends on the •OH in the bulk solution formed by ozone decomposition.

Missing Measurements of Sesquiterpene Ozonolysis Rates and Composition Limit Understanding of Atmospheric Reactivity.

Emissions of biogenic reactive carbon significantly influence atmospheric chemistry, contributing to the formation and destruction of secondary pollutants, such as secondary organic aerosol and ozone. While isoprene and monoterpenes are a major fraction of emissions and have been extensively studied, substantially less is known about the atmospheric impacts of higher-molecular-weight terpenes such as sesquiterpenes. In particular, sesquiterpenes have been proposed to play a significant role in ozone chemical loss due to the very high ozone reaction rates of certain isomers. However, relatively little data are available on the isomer-resolved composition of this compound class or its role in ozone chemistry. This study examines the chemical diversity of sesquiterpenes and availability of ozone reaction rate constants to evaluate the current understanding of their ozone reactivity. Sesquiterpenes are found to be highly diverse, with 72 different isomers reported and relatively few isomers that contribute a large mass fraction across all studies. For the small number of isomers with known ozone reaction rates, estimated rates may be 25 times higher or lower than measurements, indicating that estimated reaction rates are highly uncertain. Isomers with known ozone reaction rates make up approximately half of the mass of sesquiterpenes in concentration and emission measurements. Consequently, the current state of the knowledge suggests that the total ozone reactivity of sesquiterpenes cannot be quantified without very high uncertainty, even if isomer-resolved composition is known. These results are in contrast to monoterpenes, which are less diverse and for which ozone reaction rates are well-known, and in contrast to hydroxyl reactivity of monoterpenes and sesquiterpenes, for which reaction rates can be reasonably well estimated. Improved measurements of a relatively small number of sesquiterpene isomers would reduce uncertainties and improve our understanding of their role in regional and global ozone chemistry.

The Reaction of Ozone with the C‒H Bond Revisited

ABSTRACT This paper aimed at providing new insights into the mechanisms of ozone reactions with a selection of organic compounds, where C–H bonds were single available attack spots (1-propanol, tertiary-butanol, formate and formic acid). The involved method was based on the density functional theory (DFT). The calculations considered reactions occurring in a polar solvent, water (ɛr = 80), and a nonpolar one, cyclohexane (ɛr = 2.02). For all cases, the reaction was triggered by extraction of a hydrogen atom from the active C–H bond by ozone leading to a pair of radicals. Following this reaction, three situations occurred. Diffusion of the radicals from the solvent cage resulting in two free radicals meant H-abstraction. A fast electron transfer between the two radicals within the solvent cage resulting in the corresponding ions pair indicated pseudo hydride transfer. The recombination of the radicals within the solvent cage leading to an organic hydrotrioxide denoted pseudo insertion. In water, the systems might follow all pathways. In cyclohexane, the reaction might occur generally only via H-abstraction and pseudo insertion. An exception was the formate/O3 system, where all pathways might occur.

On the geometry and material stability of tubular PVDF-TiO2 static mixer membrane contactors for photocatalytic ozonation of micropollutants

The prevention of ozone hotspots in ozonation reactors for wastewater treatment is essential for effective degradation of micropollutants without forming harmful by-products. Membrane contactors can provide a bubble-free ozonation process that is able to decrease by-product formation, e.g., bromate formation in bromide-charged wastewater. Furthermore, the geometry of the reactor influences the distribution of dissolved ozone in a membrane contactor. Turbulence promoters can significantly decrease ozone hotspots and increase ozone mass transfer into wastewater. This work presents a fabrication methodology to produce PVDF-TiO2 helical static mixer membranes using the rotation-in-a-spinneret technology. Static mixer membranes combine the functionality of a membrane contactor and a static mixer in a single component. Furthermore, the PVDF matrix is doped with TiO2 particles as photocatalyst. Thus, we present a membrane-based photocatalytic ozonation process to increase the concentration of hydroxyl radicals for degradation of micropollutants under UV radiation. Static mixer membranes increase the ozone mass transfer coefficient by 70% compared to conventional hollow fiber membranes. Furthermore, the specific photocatalytic degradation rate of methylene blue increases by 50% using static mixer membranes. However, this work also reveals a lack of long-term stability of PVDF-TiO2 membranes in the corrosive environment of photocatalytic ozonation. The molecular weight of PVDF decreases by 11% after use in photocatalytic ozonation resulting in a loss of mechanical stability of the membranes. Similar material concepts are required based on ceramic materials which avoid wetting of the porosity.

Climate changes affecting global iodine status.

Global warming is now universally acknowledged as being responsible for dramatic climate changes with rising sea levels, unprecedented temperatures, resulting fires and threatened widespread species loss. While these effects are extremely damaging, threatening the future of life on our planet, one unexpected and paradoxically beneficial consequence could be a significant contribution to global iodine supply. Climate change and associated global warming are not the primary causes of increased iodine supply, which results from the reaction of ozone (O3) arising from both natural and anthropogenic pollution sources with iodide (I-) present in the oceans and in seaweeds (macro- and microalgae) in coastal waters, producing gaseous iodine (I2). The reaction serves as negative feedback, serving a dual purpose, both diminishing ozone pollution in the lower atmosphere and thereby increasing I2. The potential of this I2 to significantly contribute to human iodine intake is examined in the context of I2 released in a seaweed-abundant coastal area. The bioavailability of the generated I2 offers a long-term possibility of increasing global iodine status and thereby promoting thyroidal health. It is hoped that highlighting possible changes in iodine bioavailability might encourage the health community to address this issue.