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Background: Environmental contaminants may play a significant role in the development of migraine. Perchlorate, nitrate, and thiocyanate were selected for this study due to their known impact on thyroid function, which is closely linked to neurological processes. Disruptions in thyroid function have been associated with various neurological disorders, including migraines. However, there is currently no evidence linking exposure to these specific chemicals to migraine. The study aims to evaluate the association between urinary concentrations of perchlorate, nitrate, and thiocyanate with the prevalence of severe headache or migraine in U.S. adults. Methods: A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2001–2004. Utilizing electrospray tandem mass spectrometry in conjunction with ion chromatography, urinary concentrations of perchlorate, nitrate, and thiocyanate urine were measured. Multiple logistic regression models were employed to evaluate the linear correlation between perchlorate, nitrate, and thiocyanate exposure and severe headache or migraine. The non-linear relationship is described analytically using a fitted smoothing curve and a two-piecewise regression model. Subgroup analyses were used to further clarify the stability of this relationship across different populations. Results: There were 1,446 participants in this population-based study, ranging in age from 20 to 85. After adjusting for potential confounding variables, the multiple logistic regression findings demonstrated that thiocyanate was significantly positively associated with the prevalence of migraine (odds ratio [OR] = 1.18; [1.06, 1.30]; p < 0.001). There was consistency in this connection across different subgroups (p for interaction >0.05). Furthermore, there was a non-linear correlation between urinary thiocyanate and migraine. Using a fitted smoothing curve and a two-piecewise regression model, it was found that the correlation between urinary thiocyanate and migraine was U-shaped (p for Log-likelihood ratio = 0.002). According to the findings of the multiple regression analysis, there was no significant correlation between urinary perchlorate and nitrate and migraine (both p > 0.05). Conclusion: We should limit our exposure to thiocyanate by keeping it within a reasonable range, as indicated by the U-shaped correlation between urinary thiocyanate and migraine. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To analyze the distribution characteristics of perchlorate in drinking water in Chengdu and its influencing factors and explore the health risks associated with perchlorate exposure through drinking water among Chengdu residents, under the context of the initial implementation of national limit standards and clarified detection methods. Methods In 2023, an investigation was conducted at 47 water plants in Chengdu (including all municipal water plants and all large rural water plants using surface water as a source). Water samples from the source, treated water, and tap water were collected during both wet and dry seasons for perchlorate testing. The temporal and spatial distribution characteristics of perchlorate in the three types of water samples and their influencing factors were analyzed to assess the health risks of perchlorate exposure through drinking water for Chengdu residents. Results The overall detection rate of water samples was 29.8%, with concentrations below national limit standards, and perchlorate was detected in all three types of water. The detection rates during the dry season were higher than those during the wet season, with no differences in detected concentrations. There were no differences in detection rates among the three types of water samples during the dry season, while the detection rate of treated water during the wet season was higher than that of source water, with no differences in detected concentrations across both seasons. Perchlorate was detected in source water from the Minjiang River system, but not in the Tuojiang River system. The detection rate of surface water source samples was higher during the dry season than during the wet season, while there were no differences in detection rates for groundwater sources across both seasons. Only the treated water that underwent disinfection had a higher detection rate compared to fully treated water, with no differences in detected concentrations. The detection rates and concentrations of treated water using chlorination and chlorine dioxide disinfection methods showed no differences. The 19 water plants where perchlorate was detected in all three types of water were primarily located in areas with high population density in the Minjiang River basin. Conclusion Perchlorate contamination exists in Chengdu’s drinking water, with more severe pollution during the dry season and a broader contamination area in the Minjiang River system. The current treatment processes at water plants do not effectively remove perchlorate, and there may be a declining trend in perchlorate pollution levels in surface water. At this stage, the health risk of perchlorate exposure through drinking water for Chengdu residents is considered acceptable. It is recommended that the government continue to strengthen source control, technical guidance, and monitoring to ensure ongoing public health safety. [ABSTRACT FROM AUTHOR]

Perchlorate compounds are well-known for their explosive and hazardous nature. Considering previously reported perchlorate crystals of salen-type manganese (III) complexes, our study aimed to identify the specific molecular/crystal structure responsible for their explosive properties. Employing deep learning, we conducted an analysis of the Hirschfeld surface for salen-type metal complexes within a crystal structure database. The results indicate that the salen-type complex site lacks distinctive structural features, attributing its explosive potential to the chemical bonding of the perchlorate ion and the surrounding intermolecular interactions.

Nature performs critical physiological functions using a series of structurally and functionally diverse membrane proteins embedded in cell membranes, in which native ion protein channels modify the electrical potential inside and outside the cell membrane through charged ion movements. Consequently, the cell responds to external stimuli, playing an essential role in various life activities, such as nerve excitation conduction, neurotransmitter release, muscle movement, and control of cell differentiation. Supramolecular artificial channels, which mimic native protein channels in structure and function, adopt unimolecular or self‐assembled structures, such as crown ethers, cyclodextrins, cucurbiturils, column arenes, cyclic peptide nanotubes, and metal‐organic artificial channels, in channel construction strategies. Owing to the various driving forces involved, artificial synthetic ion channels can be divided into artificial cation and anion channels in terms of ion selectivity. Cation selectivity usually originates from ion coordination, whereas anion selectivity is related to hydrogen bonding, ion pairing, and anion‐dipole interactions. Several studies have been conducted on artificial cation channels, and several reviews have summarized them in detail; however, the research on anions is still in the initial stages, and related reviews have rarely been reported. Hence, this article primarily focuses on the recent research on anion channels. [ABSTRACT FROM AUTHOR]

Background: Perchlorate, nitrate, and thiocyanate are widely recognized as endocrine disrupting chemicals, which are closely related to thyroid function. Animal and human studies show a correlation between thyroid hormone and bone mineral density (BMD). However, it remains unknown whether perchlorate, nitrate, and thiocyanate were associated with BMD. This study aimed to explore the association between perchlorate, nitrate, and thiocyanate exposure with BMD. Method: A cross-sectional analysis among 5607 participants from the 2011–2018 National Health and Nutrition Examination Survey (NHANES) was conducted in the present study. Perchlorate, nitrate, and thiocyanate were detected in urine by ion chromatography. Survey-weighted generalized linear regression, restricted cubic splines, and qgcomp models were used to assess the association of BMDs with single and mixed perchlorate, nitrate, and thiocyanate exposures. In addition, age, gender, and BMI stratified these associations. Results: Negative associations were found between perchlorate and nitrate with BMDs. Furthermore, based on the qgcomp model results, the combined association of perchlorate, nitrate, and thiocyanate exposure was negatively associated with BMDs (β = −0.017, 95% CI: −0.041, −0.024 for total BMD; β = −0.017, 95% CI: −0.029, −0.005 for lumbar BMD). Additionally, there was a significant effect after gender, age, and BMI stratification between perchlorate, nitrate, and thiocyanate with BMDs in the normal weight group (β = −0.015, 95% CI: −0.020, −0.011 for total BMD; β = −0.022, 95% CI: −0.028, −0.016 for lumbar BMD) and children and adolescents group (β = −0.025, 95% CI: −0.031, −0.019 for total BMD; β −0.017, 95% CI: −0.029, −0.005 for lumbar BMD). Conclusions: The present study indicated a negative correlation between BMDs and urinary perchlorate, nitrate, and thiocyanate levels, with nitrate being the main contributor to the mixture effect. People with normal weight and children and adolescents were more likely to be affected. [ABSTRACT FROM AUTHOR]

Perchlorate and chlorate are present in various extraterrestrial celestial bodies throughout the solar system, such as Mars, the moon, and asteroids. To date, the origin mechanisms of perchlorate and chlorate on the Martian surface have been well-established; however, relatively little attention has been cast to airless bodies. Here, we experimentally investigated the potential oxidation mechanisms of chloride to chlorate and perchlorate, such as ultraviolet irradiation under H2O- and O2-free conditions and mechanical pulverization processes. Individual minerals, olivine, pyroxene, ilmenite, magnetite, TiO2 and anhydrous ferric sulfate, and lunar regolith simulants (low Ti, CLRS-1; high-Ti, CLRS-2) and their metallic iron (Fe0) bearing counterparts were examined. We found that pulverization of dry matrix material-halite mixtures, even in the presence of O2, does not necessarily lead to perchlorate and chlorate formation without involving water. Under photocatalytic and H2O- and O2-free conditions, olivine and pyroxene can produce oxychlorine (ClOx−) species, although the yields were orders of magnitude lower than those under Martian-relevant conditions. Nanophase-Fe0 particles in the lunar regolith and the common photocatalyst TiO2 can facilitate the ClOx− formation, but their yields were lower than those with olivine. The oxides ilmenite and magnetite did not efficiently contribute to ClOx− production. Our results highlight the critical role of H2O in the oxidation chloride to chlorate and perchlorate, and provide essential insights into the environmental influence on the formation of oxychlorine species on different celestial bodies. [ABSTRACT FROM AUTHOR]

Bioelectroremediation technology (BERT) is a new age greener technology which is currently been heavily studied for treatment of persistent industrial effluents such as polycyclic aromatic hydrocarbons (PAHs), perchloroethylene (PCE), perchlorate, nitrate and petroleum hydrocarbon (PHs) along with simultaneous generation of bioenergy. The focus of this review paper is on these industrial effluents because many of these effluents are toxic in nature and through contaminated water, soil or sediment enter the food chain and start to bioaccumulate thereby entering living organisms and causing severe fatal diseases. While PAHs and nitrates are major contaminant of both water and soil but their removal efficiency through BERT is much more in water sample than from soil samples, studies have shown that perchlorate and nitrate are usually co-contaminants and perchlorate, PCE and PHs are much more prevalent groundwater contaminant with good removal efficiency of these contaminants and simultaneous bioelectricity generation through BERT. Therefore, this review paper focus on role of microbial community structure as a biocatalyst in BERT along with a in-depth review of bioelectroremediation process for industrial effluent treatment involved in removing diverse pollutants integrated with energy generation from fundamentals, challenges, and future prospective dimensions. [ABSTRACT FROM AUTHOR]

A modified amphibian metamorphosis assay was performed in which Nieuwkoop and Faber (NF) stage 47 Xenopus laevis larvae were exposed to different concentrations of either perchlorate (ClO4−) or nitrate (NO3−) for 32 days. Larvae were exposed to 0.0 (control), 5, 25, 125, 625, and 3125 μg/L ClO4−, or 0 (control), 23, 71, 217, 660, and 2000 mg/L NO3−. The primary endpoints were survival, hind limb length (HLL), forelimb emergence and development, developmental stage (including time to NF stage 62 [MT62]), thyroid histopathology, wet weight, and snout‐vent length (SVL). Developmental delay as evidenced by altered stage distribution and increased MT62, a higher degree of thyroid follicular cell hypertrophy, and an increase in the prevalence of follicular cell hyperplasia was observed at concentrations ≥125 μg/L ClO4−. The no observed effect concentration (NOEC) for developmental endpoints was 25.0 μg/L ClO4− and the NOEC for growth endpoints was 3125 μg/L ClO4−. Exposure to nitrate did not adversely affect MT62, but a decreasing trend in stage distribution and median developmental stage at ≥217 mg/L NO3− was observed. No histopathologic effects associated with nitrate exposure were observed. An increasing trend in SVL‐normalized HLL was observed at 2000 mg/L NO3−. Nitrate did not alter larval growth. The NOEC for developmental endpoints was 71 mg/L NO3−, and 2000 mg/L NO3− for growth endpoints. The present study provided additional evidence that the effects and potency of nitrate and perchlorate on metamorphosis and growth in X. laevis are considerably different. A modified amphibian metamorphosis assay was performed with perchlorate (ClO4−) or nitrate (NO3−) for 32 days. The no observed effect concentration (NOEC) for developmental endpoints was 25 μg/L ClO4− and NOEC for growth endpoints was 3125 μg/L ClO4−. The NOEC for developmental endpoints was 71 mg/L, and 2000 mg/L NO3− for growth endpoints. The present study demonstrated that the effects and potency of nitrate and perchlorate on metamorphosis and growth in X. laevis are considerably different. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Perchlorate in the environment originates from both natural and anthropogenic sources. A previous study of a 300‐year Greenland ice core perchlorate record found that anthropogenic impact on environmental perchlorate became significant starting around 1980, while natural formation is the only significant source of environmental perchlorate prior to that. The study also found increased perchlorate deposition in the Arctic following certain volcanic eruptions and suggested that at least some volcanic eruptions could enhance natural perchlorate production. Here we compare the perchlorate record with the volcanic record from sulfate in the same Greenland ice core and find that only stratospheric eruptions—large eruptions injecting volcanic substances directly into the stratosphere—enhance perchlorate production. No contribution to naturally formed perchlorate is detected from non‐stratospheric eruptions. The high‐resolution ice core perchlorate data are used to quantify contributions from volcanic eruptions, non‐volcanic natural processes, as well as from human activities during different periods. For the location in the Arctic in the perchlorate Pre‐Anthropogenic Era (1701–1979), the magnitude (0.26 μg m−2 yr−1 on average) of perchlorate produced during sporadic stratospheric eruptions is comparable to that (0.23 μg m−2 yr−1) produced by non‐volcanic natural processes. In the Anthropogenic Era (1980–2006), the magnitude of both the volcanic and non‐volcanic natural perchlorate production is similar to the enhancement (0.29 μg m−2 yr−1) by human activities. Plain Language Summary: Perchlorate is widespread in the environment. In remote regions such as the Arctic, environmental perchlorate primarily comes from natural formation in the atmosphere from common‐place chemicals containing chlorine. Previously, we studied a 300‐year chronological perchlorate record from a Greenland ice core and found that, prior to 1980, perchlorate production was not affected by human activities. We also found that certain volcanic eruptions may increase the amount of perchlorate produced in the atmosphere and deposited in Greenland snow. In this study, we use the ice‐core perchlorate and sulfate data to determine that only very large eruptions can cause additional perchlorate to be formed in the atmosphere. On average, large volcanic eruptions contribute about 50% of perchlorate from all natural sources at this location in the Arctic. Since 1980, human activities have contributed approximately the same amount of perchlorate to the environment as that from all natural sources. Key Points: Atmospheric perchlorate formation is enhanced by only stratospheric volcanic eruptions, not by non‐stratospheric eruptionsVolcanic perchlorate in the Arctic is on average approximately 50% of all naturally produced perchlorate prior to 1980Contribution from anthropogenic activities since 1980 is approximately equal to that from natural perchlorate sources [ABSTRACT FROM AUTHOR]

The reactions of purine nucleic base perchlorates with the simplest 1,3-diketone – acetylacetone – were studied for the first time. It was demonstrated that adenine reacts with acetylacetone in a 1:2 molar ratio via opening of the pyrimidine fragment of the bicyclic struc- ture, elimination of a one-carbon fragment in the form of a formic acid molecule, and recyclization into 8-(4,6-dimethylpyrimidin-2-yl)- 2,4-dimethylimidazo[1,5-a]pyrimidine. Guanine, in turn, reacted with acetylacetone in a 1:1 ratio and formed 7,9-dimethyl-3H-pyrimido- [2,1-b]purin-10-ium-4-olate. In this case, the direction of heterocyclization differed from that observed in the reaction of guanine with malondialdehyde during the in vitro and in vivo formation of the minor nucleotide base M1G. The synthesized compounds were capable of causing single-strand breaks in DNA macromolecules. [ABSTRACT FROM AUTHOR]

Unique worldwide, nitrate/iodine deposits (NIDs) are located along a 700 km geological belt in the Atacama Desert, Chile. They serve as the primary source of mineral ores for the extraction of iodine, sodium, and potassium nitrates. NIDs have been relatively underexplored from a biological perspective. To address this, we collected sixteen soil samples from abandoned mines in Oficinas Pissis and Savona for chemical, mineralogical, and metagenomic analyses. The soils primarily consisted of halite and darapskite, with only one sample being predominantly composed of thenardite. Deliquescence and water activity measurements yielded values ranging from 0.02% to 0.40% and 0.47 to 0.62, respectively. To investigate the presence, identification, relative abundance, and diversity of microbial life in NID soils, we employed MiSeq high-throughput sequencing and bioinformatic tools. The dominant phyla observed were Firmicutes and Proteobacteria, with Actinobacteria and Cyanobacteria being predominant in two soil samples. Furthermore, we detected nitrate/perchlorate-reducing bacterial activity in enriched cultures from the soil samples. This study sheds light on the resilience of microbial life in the Atacama Desert NIDs, providing compelling evidence for its existence and offering insight into factors that could facilitate it within this unique environment. [ABSTRACT FROM AUTHOR]

The food chain can enrich the human body with perchlorate, a novel persistent inorganic contaminant, from the environment. The quantity of perchlorate entering the food chain cannot be ignored, despite the lack of particular facts to support it at the moment. The oxidative stress (ROS, SOD, CAT, MDA, and GSH) in Caenorhabditis elegans was detected in this study using perchlorate as the research object and Caenorhabditis elegans as the model organism. Growth and development-related indicators (body length, life span, and number of eggs laid) of Caenorhabditis elegans exposed to different concentrations of perchlorate were measured, and the associated levels of oxidative stress and growth gene expression were assessed to determine a potential mechanism of perchlorate's influence on Caenorhabditis elegans growth and development. The findings demonstrated that perchlorate dramatically decreased the Caenorhabditis elegans life cycle, spawning frequency, and body length. Additionally, Caenorhabditis elegans had elevated levels of ROS, GSH, and MDA as well as enhanced SOD and CAT activity. Daf-2, Daf--16, Daf--18, Sir-2.1, Skn-1, and other associated genes in the insulin/insulin growth factor signaling pathway may be affected. Through oxidative stress, perchlorate can activate the insulin/insulin growth factor signal pathway and associated genes, affecting growth and development. [ABSTRACT FROM AUTHOR]

BackgroundEnvironmental contaminants may play a significant role in the development of migraine. Perchlorate, nitrate, and thiocyanate were selected for this study due to their known impact on thyroid function, which is closely linked to neurological processes. Disruptions in thyroid function have been associated with various neurological disorders, including migraines. However, there is currently no evidence linking exposure to these specific chemicals to migraine. The study aims to evaluate the association between urinary concentrations of perchlorate, nitrate, and thiocyanate with the prevalence of severe headache or migraine in U.S. adults.MethodsA cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2001–2004. Utilizing electrospray tandem mass spectrometry in conjunction with ion chromatography, urinary concentrations of perchlorate, nitrate, and thiocyanate urine were measured. Multiple logistic regression models were employed to evaluate the linear correlation between perchlorate, nitrate, and thiocyanate exposure and severe headache or migraine. The non-linear relationship is described analytically using a fitted smoothing curve and a two-piecewise regression model. Subgroup analyses were used to further clarify the stability of this relationship across different populations.ResultsThere were 1,446 participants in this population-based study, ranging in age from 20 to 85. After adjusting for potential confounding variables, the multiple logistic regression findings demonstrated that thiocyanate was significantly positively associated with the prevalence of migraine (odds ratio [OR] = 1.18; [1.06, 1.30]; p 0.05). Furthermore, there was a non-linear correlation between urinary thiocyanate and migraine. Using a fitted smoothing curve and a two-piecewise regression model, it was found that the correlation between urinary thiocyanate and migraine was U-shaped (p for Log-likelihood ratio = 0.002). According to the findings of the multiple regression analysis, there was no significant correlation between urinary perchlorate and nitrate and migraine (both p > 0.05).ConclusionWe should limit our exposure to thiocyanate by keeping it within a reasonable range, as indicated by the U-shaped correlation between urinary thiocyanate and migraine.

ObjectiveA method was developed to simultaneously determine chlorate and perchlorate in vegetables and fruits using ultra-performance liquid chromatography-triple quadrupole/linear ion trap mass spectrometry （UPLC-Qtrap MS）.MethodsThe chlorate and perchlorate residues in samples were extracted using acetonitrile and water， and the supernatant was purified using GCB and PSA. The analytes were separated on a Waters Anionic Polar Pesticide （100 mm×2.1 mm， 5 µm） column using a mobile phase comprising acetonitrile and 20 mmol/L ammonium formate solution and detected using UPLC-Qtrap MS. The internal standard method was used for quantification.ResultsThe linear relationship of chlorate and perchlorate ranged from 2.0-200 and 0.5-100 µg/L， with correlation coefficients >0.999. The limits of detection were 0.006 and 0.001 mg/kg. The recoveries in spiked samples ranged from 83.3%-105.5%， and the relative standard deviations ranged from 0.97%-3.80%.ConclusionA rapid， simple， accurate， and precise method was developed for the simultaneous analysis of chlorate and perchlorate in vegetables and fruits.

Perchlorate (\begin{document}${\mathrm{ClO}}_4^- $\end{document}) is a new persistent pollutant with small molecular weight, rapid diffusion, and high stability. It is widely found in the environment, especially in the areas where fireworks are produced and set off intensively. Perchlorate impacts the normal function of thyroid gland; its environmental pollution attracted wide attention and has become a research hotspot in the field of environmental science in recent years. Column experiments using river sand from polluted site as the experiment material were conducted to study on the mechanism and influencing factors of the attenuation of perchlorate stimulated by sulfur. The effects of groundwater, iron oxides, and nitrate (\begin{document}${\mathrm{NO}}_3^- $\end{document}) were investigated in this study. The results show that sulfur is able to stimulate \begin{document}${\mathrm{ClO}}_4^- $\end{document} attenuation, which mainly depends on microbial degradation, and it is limited by the lack of essential inorganic salts and other nutrients for microorganisms. Iron oxides have a buffering effect on the decrease of pH, but have a limited stimulating effect on the \begin{document}${\mathrm{ClO}}_4^- $\end{document} attenuation in the column. Groundwater significantly enhanced sulfur-stimulated \begin{document}${\mathrm{ClO}}_4^- $\end{document} attenuation and microbial acid production. The degradation of nitrate (\begin{document}${\mathrm{NO}}_3^- $\end{document}) in groundwater is preferred to that of \begin{document}${\mathrm{ClO}}_4^- $\end{document}; when \begin{document}${\mathrm{NO}}_3^- $\end{document} concentration is less than about 10 mg/L, \begin{document}${\mathrm{ClO}}_4^- $\end{document} begins to be reducted significantly. Sulfur has the potential as the PRB reaction medium for in-situ remediation of pollutants such as \begin{document}${\mathrm{ClO}}_4^- $\end{document} and \begin{document}${\mathrm{NO}}_3^- $\end{document}. This study provides a theoretical basis and data support for the practical application of environmental remediation.

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Associations of perchlorate, thiocyanate, and nitrate exposures with bone mineral density (BMD) in adults have not previously been studied. This study aimed to estimate the associations of individual and concurrent exposure of the three chemicals with adult BMD. Based on National Health and Nutrition Examination Survey (NHANES, 2011–2018), 1618 non-pregnant adults (age ≥ 20 years and 47.0% female) were included in this study. Survey-weighted linear regression models were used to estimate individual urinary perchlorate, thiocyanate, and nitrate concentrations with lumbar spine BMD and total BMD in adults. Then, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were conducted to evaluate associations of co-occurrence of the three chemicals with adult BMD. In all participants, nitrate exposure was inversely associated with lumbar spine BMD (β = − 0.054, 95%CI: − 0.097, − 0.010). In stratification analyses, significant inverse associations were observed in female and participants older than 40 years old. In WQS regressions, significant negative associations of the weighted sum of the three chemicals with total and lumbar spine BMD (β = − 0.014, 95%CI: − 0.021, − 0.007; β = − 0.011, 95%CI: − 0.019, − 0.004, respectively) were found, and the dominant contributor was nitrate. In the BKMR models, non-linear dose–response associations of nitrate exposure with lumbar spine and total BMD were observed. These findings suggested that environmental perchlorate, thiocyanate, and nitrate exposure may reduce adult BMD and nitrate is the main contributor. [ABSTRACT FROM AUTHOR]

This article summarizes the sources, hazards, detection, and removal technology of perchlorate, and looks forward to the future research directions and development trends・ Perchlorate is an important inorganic pollutant widely used as a strong oxidant in pyrotechnics, munitions, and aerospace industries. Perchlorate can be exposed to the human body through air, food, drinking water, etc., causing thyroid dysfunction in humans and mammals, which exhibits toxicity and affects the normal physiological functions of organisms ・ With its frequent detection in water, soil, and food, it has attracted the attention of researchers・ Currently, the research on perchlorate still lacks comprehensive and in-depth survey data・ This review is expected to provide some useful references for further exploring the pollution problem of perchlorate. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The environmental contaminant perchlorate impairs the synthesis of thyroid hormones by reducing iodine uptake into the thyroid gland. Despite this known action, moderate doses of perchlorate do not significantly alter serum thyroid hormone in rat pups born to exposed dams. We examined perchlorate dosimetry and responsivity of the thyroid gland and brain in offspring following maternal exposure to perchlorate. Pregnant rat dams were delivered perchlorate in drinking water (0, 30, 100, 300, 1000 ppm) from gestational day 6 to postnatal day (PN) 21. Perchlorate was present in the placenta, milk, and serum, the latter declining in pups over the course of lactation. Serum and brain thyroid hormone were reduced in pups at birth but recovered to control levels by PN2. Dramatic upregulation of Nis was observed in the thyroid gland of the exposed pup. Despite the return of serum thyroid hormone to control levels by PN2, expression of several TH-responsive genes was altered in the PN14 pup brain. Contextual fear learning was unimpaired in the adults, supporting previous reports. Declining levels of serum perchlorate and a profound upregulation of Nis gene expression in the thyroid gland are consistent with the rapid return to the euthyroid state in the neonate. However, despite this recovery, thyroid hormone insufficiencies in serum and brain beginning in utero and present at birth appear sufficient to alter TH action in the fetus and subsequent trajectory of brain development. Biomarkers of that altered trajectory remain in the brain of the neonate, demonstrating that perchlorate is not devoid of effects on the developing brain. [ABSTRACT FROM AUTHOR]

Mars is a focus of New Space Age exploration and colonisation, but there are significant challenges to successful colonisation by humankind. Environmental microbes play a key role in supporting the ecosystems of Earth, especially within the biodegradation and bioremediation sectors. However, the repurposed roles of microbes on Mars and their associated uses to colonists remain incompletely defined. The aim of this review was to examine the key roles of microbes on Earth and how they have been employed by humans to tackle four pivotal environmental challenges associated with the colonisation of Mars, namely the physical environment, the creation of a hospitable environment via terraforming, environmental sustainability and life support, and finally, renewable processing technologies. Some species of microbes were found to be tolerant of the ever-changing physical environment on Mars (freeze–thaw and UVC exposure) making them useful for bioremediation applications. Employing perchlorate-remediating microbes for their ability to bioremediate the soils of sodium perchlorate, which is present in Martian soils, in addition to their innate ability to cycle nutrients through the biosphere showed promise in establishing sustained crops to support colonists. The employment of terrestrial environmental microbes is a necessary part of overcoming key environmental challenges to successfully colonise Mars. Without this, future New Space exploration is unlikely to be successful. [ABSTRACT FROM AUTHOR]

Natural impurities such iron, sulphates, chlorides, and heavy metals that cannot be removed by recrystallization are present in the magnesia that is formed. One method for making magnesium perchlorate includes combining per chloric acid and magnesite dust, a process that generates a lot of heat and hydrogen gas during the reaction. Magnesite is leached using an aqueous per chloric acid solution with a 500 rpm stirring speed. The following factors were taken into account in this study: fluctuation in leaching temperature (°K), per chloric acid volume percentage, and time of leaching. Magnesium perchlorate recovery is 97.3% with a temperature increase to 333.15 K and 100% with an increase in leaching time to 1 h. Dehydration of magnesium chloride was tried through thermochemical processing with several compounds and the results are not encouraging. Experimental studies have also been carried out on the electrochemical preparation of magnesium hydroxide from magnesium chloride. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Perchlorate is a widespread environmental pollutant and a known thyroid hormone disruptor. Little is known about the sources and pathways of human exposure to perchlorate. We measured perchlorate in drinking water, foodstuffs, indoor dust and urine collected from various locations in the United States, with a vast majority of them from New York State. The highest concentration of perchlorate was found in indoor dust, at a geometric mean (GM) concentration of 280 ng/g, followed by foodstuffs including beverages (1.77 ng/g) and drinking water (0.09 ng/mL). Among nine categories of foodstuffs analyzed, perchlorate concentrations as high as 839 ng/g were found in vegetables. The estimated average perchlorate exposure dose for adults from various sources was 141 ng/kg body weight (BW)/day. Previously reported perchlorate concentrations in breast milk from the United States in 2007 were used for the estimation of exposure doses in infants, and were 1580, 1230, and 1010 ng/kg BW/day for 0–3, 3–6, and 6–12 months of age, all exceeded the United States Environmental Protection Agency's (EPA) chronic reference dose (700 ng/kg BW/day). Breastfeeding was the dominant exposure pathway accounting for > 90% of perchlorate exposure among infants < 1 year, whereas milk, vegetables, and beverages were the dominant exposure sources (73–83%) for age groups > 1 year. Perchlorate was detected in all human urine collected from Albany, New York (N = 31) at a GM concentration of 2.30 ng/mL. The GM perchlorate exposure doses calculated from urinary concentrations, through a reverse dosimetry approach, were 46.1 and 37.8 ng/kg BW/day for age groups 16–21 and > 21 years, respectively, which were similar to those calculated from external sources of exposure.

ObjectiveTo assess the exposure and health risks from perchlorates in food and tea among Chinese residents grouped by key and common areas.MethodsPerchlorate content data for food and tea in China were collected from the literature. Combined with data from the Chinese Total Diet Study in 2015 and using the hazard quotient， the estimated dietary exposure to perchlorate in different areas was assessed and compared using several health-based guidance values.ResultsThe highest mean perchlorate content was 175.54 μg/kg in tea. The results of the probability assessment showed that vegetables were critical exposure pathways in the Chinese population， accounting for 79.40% of total daily perchlorate intake. The 99% daily perchlorate intake of Chinese populations was lower than the provisional maximum tolerable daily intake （PMTDI， 10 μg/kg∙BW） set by the Joint FAO/WHO. However， the daily perchlorate intake of 4.96% and 26.57% of the residents in two areas far exceeded the temporary tolerable daily intake （tTDI， 0.7 μg/kg∙BW） set by China. In tea， 95% of daily perchlorate intake was lower than the PMTDI， but the daily perchlorate intakes of 57.47% and 77.94% of the tea drinkers in the two areas exceeded the tTDI.ConclusionThe risk of exposure to perchlorate via dietary intake in the Chinese population is generally low； however， there are key areas where the exposure is significantly higher than those in other areas owing to high local pollution.

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chlorate and perchlorate are emerging pollutants that may interfere with thyroid function. Since they are highly water soluble, chlorate and perchlorate in tea leaves cause health concerns but have scarcely been studied. In this study, chlorate and perchlorate concentrations in 216 tea samples from different regions of China were determined. Perchlorate was detected in all the samples with a median concentration of 44.1 μg kg−1, while the chlorate detection frequency was 15.7%. We observed regional differences in perchlorate contents in tea leaves, with the highest quantity found in the central region of China. Except for dark tea, the concentration of perchlorate in tea infusions decreased with the increased number of times the tea leaves were brewed. The hazard quotients (HQs) of chlorate and perchlorate in all the samples were less than 1, suggesting negligible health risks caused by these pollutants from tea consumption. To the best of our knowledge, this is the first study to investigate chlorate and perchlorate contamination in tea infusions by simulating brewing behavior. [ABSTRACT FROM AUTHOR]

Perchlorates are present at high concentrations in Martian regolith and pose an additional challenge to the survival of terrestrial life on Mars. Some microinvertebrates can resist extreme conditions (e.g. low temperatures, lack of oxygen and radiation), making them suitable model species for space experiments. Clarification of whether they can tolerate high levels of perchlorates is crucial for understanding the scope of application of small invertebrates in Mars exploration. We assessed the activity of some Crustacea, Nematoda, Rotifera and Tardigrada exposed to 0.25–1.00% magnesium perchlorate. The number of active specimens decreased with exposure time and perchlorate concentration. However, exposure of selected species to 0.25% perchlorate for 24 or 72 h showed activity in some specimens. Only Caenorhabditis elegans , Lecane inermis and Artemia salina exhibited activity after 24 h exposure to 1.00% perchlorate. Lecane inermis was the only species to remain active after 72 h of incubation with 1.00% perchlorate. Transferring specimens to distilled water after perchlorate exposure generally resulted in high recovery rates. The study indicates that all the tested invertebrates resist extremely high concentrations of perchlorates, which has implications for further research on their potential use in development of biological systems with improved performance and utility on Mars. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Environmental contaminants are often flagged as thyroid system disruptors due to their actions to reduce serum thyroxine (T4) in rodent models. The presence of a periventricular heterotopia (PVH), a brain malformation resulting from T4 insufficiency, has been described in response to T4 decrements induced by pharmaceuticals that reduce the hormone synthesis enzyme thyroperoxidase. In this report, we extend these observations to the environmental contaminant perchlorate, an agent that interferes with thyroid status by inhibiting iodine uptake into the thyroid gland. Pregnant rat dams were administered perchlorate in their drinking water (0, 30, 100, 300, 1000 ppm) from gestational day (GD) 6 until the weaning of pups on postnatal day (PN) 21. Serum T4 was reduced in dams and fetuses in late gestation and remained lower in lactating dams. Pup serum and brain T4, however, were not reduced beyond PN0, and small PVHs were evident in the brains of offspring when assessed on PN14. To emulate the developmental time window of the brain in humans, a second study was conducted in which pups from perchlorate-exposed dams were administered perchlorate orally from PN0 to PN6. This treatment reduced serum and brain T4 in the pup and resulted in large PVH. A third study extended the period of serum and brain TH suppression in pups by coupling maternal perchlorate exposure with maternal dietary iodine deficiency (ID). No PVHs were evident in the pups from ID dams, small PVHs were observed in the offspring of dams exposed to 300 ppm of perchlorate, and very large PVHs were present in the brains of pups born to dams receiving ID and perchlorate. These findings underscore the importance of the inclusion of serum hormone profiles in pregnant dams and fetuses in in vivo screens for thyroid-system-disrupting chemicals and indicate that chemical-induced decreases in fetal rat serum that resolve in the immediate postnatal period may still harbor considerable concern for neurodevelopment in humans. [ABSTRACT FROM AUTHOR]

Perchlorate, a hazardous pollutant, is mainly found in untreated wastewater from urban and industrial sites and unregulated surface and groundwater sources. Effective monitoring of perchlorate in water is essential to mitigate its potential harmful effects. Microfluidic systems are evolving as promising technologies for detecting chemical contaminants in water due to their ability to enable rapid analysis with minimal consumption of reagents and samples. The integration of paper-based microfluidic devices with digital imaging has garnered enormous attention from the perspective of developing portable analytical techniques. Nevertheless, there is a need for further exploration to fully realize the potential of these systems. This study aimed to develop and evaluate the performance of a microfluidic paper-based device for measuring perchlorate levels in water samples. Smartphone-based digital imaging was integrated with microfluidic paper-based analytical device to establish a reliable colorimetric method for detecting perchlorate contamination. The results demonstrated successful quantitative estimation of perchlorate levels in water samples using a colorimetric assay based on the methylene blue-perchlorate reaction. Real-time, on-site colorimetric data were collected using a digital smartphone, and image processing methods were used to detect the occurrence of perchlorate in water samples from digital images. The developed approach yielded a broad linear response ranging from 4 to 12 µg/L (R2 = 0.97) for perchlorate detection, with a limit of detection of 3.41 µg/L and a limit of quantification of 10.34 µg/L. The findings underscore the effectiveness of colorimetric analysis and digital imaging for paper-based analytical devices. The limitations of this method include the capability to detect only a single analyte and the requirement for additional steps in image processing to obtain analytical results. Future developments should focus on designing devices for simultaneous detection of multiple contaminants and exploring automated methods of image analysis. [ABSTRACT FROM AUTHOR]

ObjectiveTo understand the pollution level of perchlorate and chlorate in infant formula milk powder in Inner Mongolia evaluate the dietary intake risk of perchlorate and chlorate in infants， and provide a scientific basis for guiding the healthy diet of infants in Inner Mongolia.MethodsA total of 539 infant formula milk powder sold in each segment in Inner Mongolia were collected， and 254 milk powder flushing water （drinking water that may be used in the flushing and mixing of milk powder） were collected. The contents of perchlorate and chlorate in infant formula milk powder and milk powder washing and mixing water were detected by ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Based on the consumption data of infants and young children in Inner Mongolia in the 2015 China Infant Food Consumption survey data， the risk of dietary intake of perchlorate and chlorate in infant formula milk powder in Inner Mongolia was calculated by simple distribution assessment and cumulative exposure assessment.ResultsThe overall detection rate of perchlorate in infant formula milk powder was 92.39% （498/539）. The detection value was not detected up to 89.30 μg/kg， with an average of 14.45 μg/kg and a median of 9.00 μg/kg. The overall detection rate of chlorate was 73.10% （394/539）， and the detection value was not detected up to 1 061.00 μg/kg， with an average of 93.25 μg/kg and a median of 45.50 μg/kg. The overall detection rate of perchlorate in milk powder was 67.32% （171/254）， and the detection value was not detected up to 26.59 μg/L， with an average value of 1.25 μg/L. The overall detection rate of chlorate was 30.71% （78/254）， and the detection value was not detected up to 927.66 μg/L， with an average value of 24.03 μg/L. The health risk of perchlorate and chlorate intake through milk powder was assessed as low for infants aged 0 to 36 months. Furthermore， the exposure of the high consumer population （P95） did not exceed the health guidance value.ConclusionThere is perchlorate and chlorate contamination in infant formula powder in Inner Mongolia. However， under the current pollution level， the health risk of perchlorate and chlorate ingestion through milk powder is low for infants under the age of 0-36 months. In addition， the exposure level of the high consumption group （P95） did not exceed the health guidance value， and the health risk was low. The exposure level of P95 in infants aged zero to six months is higher， and further attention should be paid to their health risks.

A method for simultaneous determination of chlorate and perchlorate amounts in meat by high performance liquid chromatography-tandem mass spectrometry was developed. Samples were extracted with acetonitrile/water (13:7, V:V ) and centrifuged. The obtained supernatants were purified on a PRiME HLB solid phase extraction column, followed by an Acclaim Trinity P1 ion exchange column with the gradient elution of acetonitrile and 20 mmol/L ammonium acetate as the mobile phase to afford chlorate and perchlorate. MS/MS was performed in ESI+ and multiple reaction monitoring mode with an internal standard for quantification. The results showed chlorate and perchlorate had calibration curves with good linearity in the ranges of 2~200.0 ng/mL and 1~100.0 ng/mL respectively, with corresponding correlation coefficients being 0.9983 and 0.9998. The detection limits of the method were 2.0 and 1.0 μg/kg, respectively. The recovery rates of chlorate and perchlorate were 91.0%~105.7% and 94.2%~110.5% respectively, at the addition levels of 6.0, 20, 40, 200 μg/kg, and 3.0, 10, 20, 100 μg/kg. The relative standard deviations for chlorate and perchlorate were 1.8%~9.7% and 0.7%~9.4% respectively. This method would be easy to use and has high detection sensitivity and good stability, and could well meet the requirements of determining chlorate and perchlorate amounts in meat.

Three novel cadmium(II) coordination compounds, the dimeric [Cd(CH3COO)2(nia)2]2 (1), the polymeric {[Cd(nia)4](ClO4)2}n (2), and the monomeric [Cd(H2O)3(nia)3](ClO4)2·nia (3), were prepared in the reactions of the nicotinamide (pyridine-3-carboxamide, nia) with the corresponding cadmium(II) salts. All prepared compounds were characterized by elemental analyses, FT-IR spectroscopy, TGA/DTA, and single crystal X-ray analysis. The impact of anions (acetate, perchlorate) and solvent used on the dimensionality of cadmium(II) complexes and the cadmium(II) coordination environment was investigated. The bridging capabilities of acetate ions enabled the formation of dimers in the crystal structure of 1. It was shown that the dimensionality of perchlorate complexes depends on the solvent used. The coordination polymer 2 is isolated from an ethanol solution, while monomeric compound 3 was obtained by using a water/ethanol mixture as a solvent. The pentagonal-bipyramidal coordination of cadmium(II) was found in the presence of chelating and bridging acetate ions in 1. In the presence of non-coordinating perchlorate anions in 2 and 3, the coordination geometry of cadmium(II) is found to be octahedral. The supramolecular amide-amide homosynthon R22(8) was preserved in the hydrogen-bonded frameworks of all three compounds.

ABSTRACTMicroorganisms are essential drivers of earth’s geochemical cycles. However, the significance of elemental redox cycling mediated by microorganisms is often underestimated beyond the most well-studied nutrient cycles. Phosphite, (per)chlorate, and iodate are each considered esoteric substrates metabolized by microorganisms. However, recent investigations have indicated that these metabolisms are widespread and ubiquitous, affirming a need to continue studying the underlying microbiology to understand their biogeochemical effects and their interface with each other and our biosphere. This review focuses on combining canonical techniques of culturing microorganisms with modern omic approaches to further our understanding of obscure metabolic pathways and elucidate their importance in global biogeochemical cycles. Using these approaches, marker genes of interest have already been identified for phosphite, (per)chlorate, and iodate using traditional microbial physiology and genetics. Subsequently, their presence was queried to reveal the distribution of metabolic pathways in the environment using publicly available databases. In conjunction with each other, computational and experimental techniques provide a more comprehensive understanding of the location of these microorganisms, their underlying biochemistry and genetics, and how they tie into our planet’s geochemical cycles.

In this work, a new coating of boron-doped diamond ultra-nanocrystalline (U-NBDD), tailored to prevent massive formation of perchlorates during disinfection, is evaluated as electrode for the reclaiming of treated secondary wastewater by the electrochemically assisted disinfection process. Results obtained are compared to those obtained by using a standard electrode (STD) that was evaluated as a standard in previous research showing outstanding performance for this application. First tests were carried out to evaluate the chlorine speciation obtained after the electrolysis of synthetic chloride solutions at two different ranges of current densities. Concentrations of hypochlorite obtained using the U-NBDD anode at 25 mA cm−2 were 1.5-fold higher, outperforming STD anode; however, at 300 mA cm−2, an overturn on the behavior of anodes occurs where the amount of hypochlorite produced on STD anode was 1.5-fold higher. Importantly, at low current density the formation of chlorates and perchlorates is null using U-NBDD. Then, the disinfection of the real effluent of the secondary clarifier of a municipal wastewater treatment facility is assessed, where inactivation of Escherichia coli is achieved at low charge applied per volume electrolyzed (0.08 A h L−1) at 25 mA cm−2 using the U-NBDD. These findings demonstrate the appropriateness of the strategy followed in this work to obtain safer electro-disinfection technologies for the reclaiming of treated wastewater. [ABSTRACT FROM AUTHOR]

Abstract Perchlorate has become one of the most significant contaminants in our environment. Perchlorate is responsible for difficulties relating to both human and environmental health. In contaminated areas, microorganisms that degrade perchlorate are now promising bioremediation techniques. Microorganisms based on chemical, physical, and other biological approaches are favored for economic and environmental reasons. These microbes were accountable for the breakdown of perchlorate in the environment. This state-of-the-art review explores the perchlorate is a nonvolatile anion that is non-reactive and kinetically stable due to the most oxidized form of the chlorine atom. However, several industrial applications of perchlorate contamination have become a global concern. Perchlorate has several undesirable effects on the ecosystem as it degrades the environmental quality along with numerous anthropogenic activities. Currently, perchlorate-reducing microbes have proven to be a promising approach toward bioremediation. It can be hypothesized that bioreactors using perchlorate-reducing microbes would facilitate water treatment’s efficacy and prevent several deadly diseases caused by perchlorate contamination. Additionally, this study delves into innovative and conventional remediation techniques used to mitigate perchlorate contamination. It covers a wide range of strategies, including biological treatments, ion exchange, chemical reduction, and phytoremediation, among others. Furthermore, it discusses each technique’s advantages, limitations, and feasibility, considering factors such as cost, scalability, and site-specific conditions. [ABSTRACT FROM AUTHOR]

Year‐round precipitation in coastal East Antarctica and Antarctic Peninsula was used to investigate the seasonal patterns in sources of atmospheric perchlorate (ClO4− ${{\text{ClO}}_{4}}^{-}$). Although featuring distinct climates, the two locations exhibit similar annual mean and seasonal cycles of ClO4− ${{\text{ClO}}_{4}}^{-}$ concentration, with higher values in autumn and lower concentrations in winter and spring. Tropospheric formation dominates atmospheric ClO4− ${{\text{ClO}}_{4}}^{-}$ in spring and summer, which is influenced by both oxidants levels and environmental conditions (e.g., air humidity). Tropospheric ClO4− ${{\text{ClO}}_{4}}^{-}$ production may also be promoted by elevated levels of oxidants brought by air mass from the interior Antarctic ice sheet in spring and summer. The autumn concentration maximum may originate from ClO4− ${{\text{ClO}}_{4}}^{-}$ produced in the stratosphere through reactions between reactive chlorine and ozone during spring and summer. In winter, the stratospheric input may contribute to ClO4− ${{\text{ClO}}_{4}}^{-}$ via polar stratospheric clouds sedimentation. Plain Language Summary: Perchlorate (ClO4− ${{\text{ClO}}_{4}}^{-}$) is an inorganic anion with a persistent presence in the environment, where its exposure can pose a significant health risk to humans. Environmental ClO4− ${{\text{ClO}}_{4}}^{-}$ is derived from both man‐made and natural sources. Natural ClO4− ${{\text{ClO}}_{4}}^{-}$, widespread in the environment, is thought to be formed in the atmosphere. However, knowledge on the sources and, in particular, the formation mechanisms of natural ClO4− ${{\text{ClO}}_{4}}^{-}$ is quite limited. Antarctica, with negligible man‐made sources, is one of the best regions for investigations on natural ClO4− ${{\text{ClO}}_{4}}^{-}$. Year‐round precipitation samples were collected at China Zhongshan Station located in coastal East Antarctica and China Great Wall Station on King George Island, Antarctic Peninsula. Results show that atmospheric ClO4− ${{\text{ClO}}_{4}}^{-}$ concentration presents obvious seasonal cycles, which are related to variations in sources. A significant amount of ClO4− ${{\text{ClO}}_{4}}^{-}$ is associated with tropospheric chemistry in spring and summer. Precursor levels, environmental conditions, and air mass from the interior Antarctica may influence tropospheric ClO4− ${{\text{ClO}}_{4}}^{-}$ formation. The maximum concentration in autumn may originate from ClO4− ${{\text{ClO}}_{4}}^{-}$ formed in the stratosphere during spring and summer, and the stratospheric input may also contribute to atmospheric ClO4− ${{\text{ClO}}_{4}}^{-}$ in winter. Key Points: Antarctic atmospheric perchlorate (ClO4− ${{\text{ClO}}_{4}}^{-}$) concentration at different locations exhibits a clear seasonal cycleThe highest concentration in autumn is likely related to ClO4− ${{\text{ClO}}_{4}}^{-}$ produced in the stratosphere in spring and summerMajor source of ClO4− ${{\text{ClO}}_{4}}^{-}$ in spring and summer is tropospheric formation influenced by both oxidants and environmental conditions [ABSTRACT FROM AUTHOR]

Fireworks are used globally, mostly for recreational purposes, despite overwhelming evidence that they negatively affect wildlife, domestic animals, and the environment. Fireworks cause short-term noise and light disturbance, causing distress in domestic animals that may be managed before or after a fireworks event, but impacts to wildlife can be on a much larger scale. The annual timing of some large-scale fireworks events coincides with migratory orreproductive behaviour of wildlife, and thus may have adverse long-term population effects on them. Fireworks residues also contribute significantly to chemical pollution of soil, water, and air, which has implication for human as well as animal health. Modern technological alternatives to traditional fireworks – both ‘eco-friendly’ fireworks, and reusable drone and laser-based lightshows – provide safer, ‘greener’ alternatives that also present a sustainable way forward for maintaining cultural traditions without perpetuating their adverse impacts. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)