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Verticillium dahliae, the causal agent of Verticillium wilt of strawberry, is a major soilborne pathogen in California strawberry production. Recent shifts in disease management have necessitated alternative methods for disease control. Two field experiments were conducted to examine the efficacy of sequential fumigant applications for crop termination and bed fumigation to reduce Verticillium dahliae inoculum density in a naturally infested field. Fumigant efficacy was evaluated for crop termination and for reducing pathogen survival in host tissue. Crop termination was conducted using metam potassium and metam sodium. Bed fumigation was conducted using both metam products and chloropicrin. For plots that were subject to both crop termination and bed fumigation, inoculum levels were somewhat reduced (3–6 CFU/g of soil) but not to a level below the disease threshold for strawberry (2 CFU/g of soil). Plots subjected to crop termination with metam potassium and bed fumigation with chloropicrin resulted in the lowest V. dahliae inoculum density. Injury due to crop termination ranged from 53% to 77% at 7 days after fumigation (DAF) and 73–89% at 14 DAF. The odds ratio of V. dahliae survival in the terminated crop were lower than in crops not terminated and V. dahliae survival was less likely at 14, compared to 7 DAF. In the crop terminated with metam potassium, the odds ratio of pathogen survival in the petiole versus the crown was 0.9–1.4. This research shows that crop termination could constitute management strategies for Verticillium wilt of strawberry.

A two-year field trial was conducted in order to assess techniques to control ginger blast and explore the effects of fumigants on soil bacterial microorganisms and ginger metabolites. This study examined the effects of dazomet and chloropicrin on the control of ginger blast and their influence on ginger yield in Luoping County, Yunnan Province, China. The results showed that in 2022, the control effectiveness of dazomet and chloropicrin treatments on ginger blast was 84.33% and 94.67%, respectively. The corresponding yields were 50,154.40 kg/hm2 and 50,296.90 kg/hm2. In 2023, the control effectiveness of dazomet and chloropicrin treatments on ginger blast were 86.33% and 93.67%, respectively, and the yields were 65,115.83 kg/hm2 and 65,337.93 kg/hm2. In both years, the incidence of ginger blast in the control group reached nearly 100%, leading to the near extinction of the crop. Additionally, in 2023, 16S rRNA high-throughput sequencing and non-targeted metabolomics techniques were used to analyze the effects of the fumigants on soil bacterial microorganisms and the metabolites in ginger. The results showed that the diversity and richness of soil bacterial communities were lower than those in the control group at 0 and 120 days after treatment with two fumigants, but the relative abundances of beneficial bacteria such as Pseudomonas increased at 60 days, and the relative abundances of Actinobacteria, Gemmatimonadetes, and Bacillus increased at 120 days. The abundance of Firmicutes also increased after 120 days of chloropicrin treatment. The non-targeted metabolic LC–MS results showed that the production of phenols and terpenoids was upregulated after dazomet and chloropicrin treatments. The contents of amino acids and their derivatives were also upregulated. This upregulation of metabolites was beneficial to the flavor quality of ginger and enhanced its anti-inflammatory, anti-tumoral, and antioxidant effects. [ABSTRACT FROM AUTHOR]

Soil fumigation is considered a method to control soil-borne diseases and solve crop continuous cropping obstacles. However, fumigant residues in the soil are detrimental to soil health. Though substrate cultivation is a cultivation mode that can promote plant growth, studies to date on whether substrate cultivation can replace soil fumigation for the control of soil pathogens are limited. In this study, the effects of chloropicrin fumigation (Pic) and substrate cultivation (SC) on yam growth, soil pathogens, soil nutrients, and microbial communities were demonstrated using a 2-year field experiment. The results showed that SC significantly increased the content of soil organic matter (SOM), available phosphorus, and available potassium compared with Pic. In addition, SC could effectively reduce the number of Fusarium spp. and Phytophthora spp., decrease the rate of diseased yam plants, and significantly increase the yam yield. Moreover, SC significantly increased the abundance of beneficial microorganisms such as Actinobacteriota, Acidobacteriota, and Bacillus in soil. Correlation analysis showed that yam yield exhibited a negative relation with the number of soil pathogens and a positive correlation with SOM. Our study suggests that substrate cultivation can be an alternative to soil fumigation to control soil pathogens and protect soil health. [ABSTRACT FROM AUTHOR]

Soil disinfestation has been widely used as an effective strategy to improve soil health and crop yield by suppression of soil-borne plant pathogens, but its effect on soil organic carbon (SOC), a crucial factor linked to climate change, remains unknown. A microcosm trial was conducted to evaluate microbial residue carbon (MRC) and its contribution to SOC under chemical soil disinfestation (CSD) with quicklime (QL) and chloropicrin (CP), as well as anaerobic soil disinfestation (ASD) with maize straw (MASD) and soybean straw (SASD). The SOC concentrations were increased by both CSD and ASD. Also, total SOC-normalized MRC concentration was enhanced, with a considerable increase in soil bacterial and fungal MRC, particularly evident under CP and SASD treatment. Due to broad-spectrum biocidal activities, decreased SOC-normalized microbial biomass carbon (MBC) was consistent with the reductions in bacterial and fungal phospholipid fatty acids (PLFAs), consequently increasing MRC accumulation under CSD. Similarly, ASD decreased fungal PLFAs while shifting bacterial PLFAs from aerobic to anaerobic taxa or from gram-negative to -positive taxa, both of which contributed to both MBC and MRC buildup. Collectively, the findings demonstrate that ASD can efficiently increase SOC concentration, with distinct mechanisms underlying MRC generation when compared to traditional CSD. [ABSTRACT FROM AUTHOR]

Ocular tissue, especially the cornea, is overly sensitive to chemical exposures. The availability and adoption of chemical threat agent chloropicrin (CP) is growing in the United States as a pesticide and fumigant; thereby increasing the risk of its use in warfare, terrorist attacks and non-intentional exposure. Exposure to CP results in immediate ocular, respiratory, and dermal injury; however, we lack knowledge on its mechanism of toxicity as well as of its breakdown products like chlorine and phosgene, and effective therapies are elusive. Herein, we have reviewed the recent findings on exposure route, toxicity and likely mechanisms of CP induced ocular toxicity based on other vesicating chemical warfare agents that cause ocular injury. We have focused on the implication of their toxicity and mechanistic outcomes in the ocular tissue, especially the cornea, which could be useful in the development of broad-spectrum effective therapeutic options. We have discussed on the potential countermeasures, overall hallmarks and challenges involved in studying ocular injuries from chemical threat agent exposures. Finally, we reviewed useful available technologies and methods that can assist in the identification of effective medical countermeasures for chemical threat agents related ocular injuries. [Display omitted] • Chloropicrin, a warfare agent, is used as a pesticide and fumigating agent. • Chloropicrin is a choking chemical threat agent that caused severe ocular injury. • The mechanism of ocular injury from chloropicrin exposure is unknown. • There is currently no available targeted treatment for chloropicrin induced injuries. [ABSTRACT FROM AUTHOR]

Pivotal to this research is the computational investigation of the nanosensing resourcefulness of silicon carbide, Si12C12 nanocage for the adsorption and detection of chloropicrin (CP). To fill this research gap, pristine Si12C12 was functionalized with Ge and the interaction configuration was modified into four adsorbent-adsorbate systems: using CP and the pristine Si12C12 at the Si and C sites respectively with GeSi12C11 and GeSi11C12 serving as complementary adsorbents for the third and fourth interactions. The electronic properties, thermodynamics, density-of-state and topology were investigated in addition to the adsorption energies all at the ωB97XD/aug-cc-pVDZ levels of theory. Also, the Cohesive Energy Density (CED), and MD simulation were carried out to investigate the stability of the nanocages and their respective interactions. The energy gap (Egp) varied from 5.127 to 6.220 eV with CP@C_Si12C12 and CP@GeSi12C11 at the lower and upper extremes while the ∆H, ∆G and S, which were all spontaneous and favourable had value ranges of −66.322 to −74.932 eV, −66.797 to −75.424 eV and 175.202 to 188.331 Cal/molK−1 respectively. The magnitude of the adsorption energy for the interactions showed strong chemisorption with the two lowest values of −67.025 and −67.231 eV corresponding to CP@Si_Si12C12 and CP@C_Si12C12 respectively. Furthermore, the non-covalent interaction (NCI) investigation complemented by the quantum theory of atoms in molecules (QTAIM) analysis showed that van der Waals forces were formed at CP-sensor interphase of CP@C_Si12C12 while varying degrees of steric hindrances were equally observed in addition to the van der Waals forces in the other three. From the sensor mechanism investigation, the most feasible recovery time of 5.98 × 1029s and 4.38 × 1029s was predicted for CP@C_Si12C12 and CP@Si_Si12C12 respectively. [ABSTRACT FROM AUTHOR]

A two-year field trial was conducted in order to assess techniques to control ginger blast and explore the effects of fumigants on soil bacterial microorganisms and ginger metabolites. This study examined the effects of dazomet and chloropicrin on the control of ginger blast and their influence on ginger yield in Luoping County, Yunnan Province, China. The results showed that in 2022, the control effectiveness of dazomet and chloropicrin treatments on ginger blast was 84.33% and 94.67%, respectively. The corresponding yields were 50,154.40 kg/hm2 and 50,296.90 kg/hm2. In 2023, the control effectiveness of dazomet and chloropicrin treatments on ginger blast were 86.33% and 93.67%, respectively, and the yields were 65,115.83 kg/hm2 and 65,337.93 kg/hm2. In both years, the incidence of ginger blast in the control group reached nearly 100%, leading to the near extinction of the crop. Additionally, in 2023, 16S rRNA high-throughput sequencing and non-targeted metabolomics techniques were used to analyze the effects of the fumigants on soil bacterial microorganisms and the metabolites in ginger. The results showed that the diversity and richness of soil bacterial communities were lower than those in the control group at 0 and 120 days after treatment with two fumigants, but the relative abundances of beneficial bacteria such as Pseudomonas increased at 60 days, and the relative abundances of Actinobacteria, Gemmatimonadetes, and Bacillus increased at 120 days. The abundance of Firmicutes also increased after 120 days of chloropicrin treatment. The non-targeted metabolic LC–MS results showed that the production of phenols and terpenoids was upregulated after dazomet and chloropicrin treatments. The contents of amino acids and their derivatives were also upregulated. This upregulation of metabolites was beneficial to the flavor quality of ginger and enhanced its anti-inflammatory, anti-tumoral, and antioxidant effects.

Soil fumigation is considered a method to control soil-borne diseases and solve crop continuous cropping obstacles. However, fumigant residues in the soil are detrimental to soil health. Though substrate cultivation is a cultivation mode that can promote plant growth, studies to date on whether substrate cultivation can replace soil fumigation for the control of soil pathogens are limited. In this study, the effects of chloropicrin fumigation (Pic) and substrate cultivation (SC) on yam growth, soil pathogens, soil nutrients, and microbial communities were demonstrated using a 2-year field experiment. The results showed that SC significantly increased the content of soil organic matter (SOM), available phosphorus, and available potassium compared with Pic. In addition, SC could effectively reduce the number of Fusarium spp. and Phytophthora spp., decrease the rate of diseased yam plants, and significantly increase the yam yield. Moreover, SC significantly increased the abundance of beneficial microorganisms such as Actinobacteriota, Acidobacteriota, and Bacillus in soil. Correlation analysis showed that yam yield exhibited a negative relation with the number of soil pathogens and a positive correlation with SOM. Our study suggests that substrate cultivation can be an alternative to soil fumigation to control soil pathogens and protect soil health.

BACKGROUND: Soil fumigation can change soil nutrient cycling processes by affecting soil beneficial microorganisms, which is a key issue for soil fertility. However, the effect of combined application of fumigant and fungicide on soil phosphorus (P) availability remains largely unclear. We investigated the effects of the fumigant chloropicrin (CP) and the fungicide azoxystrobin (AZO) on soil phosphatase activity and soil P fractions in ginger production using a 28‐week pot experiment with six treatments: control (CK), a single application of AZO (AZO1), double applications of AZO (AZO2), CP‐fumigated soil without AZO (CP), CP combined with AZO1 (CP + AZO1) and CP combined with AZO2 (CP + AZO2). RESULTS: AZO application alone significantly increased the soil labile P fractions (Resin‐P + NaHCO3‐Pi + NaOH‐Pi) at 9 weeks after planting (WAP) but decreased the soil phosphatase activity at 28 WAP. CP fumigation significantly reduced the soil phosphatase activity but increased the proportions of soil labile P fractions (Resin‐P + NaHCO3‐Pi + NaHCO3‐Po) to total P (TP) by 9.0–15.5% throughout the experiment. The combined application of CP and AZO had a synergistic effect on soil phosphatase activity and soil P fractions compared with a single application. CONCLUSION: Although AZO application and CP fumigation can increase soil available P in the short term, they might negatively affect soil fertility in the long run by inhibiting soil phosphatase activity. Soil microbial activities, especially microorganisms related to P cycling, may be responsible for the variations in soil P availability, but further research is needed. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

HOCl and UV activated HOCl (UV/HOCl) have been applied for water disinfection and abatement of organic contaminants. However, the production of toxic byproducts in the HOCl and UV/HOCl treatment should be scrutinized. This contribution comparatively investigated the elimination of 4-nitrophenol and the generation of chlorinated byproducts in HOCl and UV/HOCl treatment processes. 61.4% of 4-nitrophenol was removed by UV/HOCl in 5 min with HOCl dose of 60 μM, significantly higher than that by UV (3.3%) or HOCl alone (32.0%). Radical quenching test showed that HO• and Cl• played important roles in UV/HOCl process. 2-Chloro-4-nitrophenol and 2,6-dichloro-4-nitrophenol were generated consecutively in HOCl process; but their formation was less in the UV/HOCl process. Trichloronitromethane (TCNM) was only found in the UV/HOCl process, and its production increased with increasing HOCl dosage. Besides chlorinated products hydroxylated and dinitrated products were also identified in the UV/HOCl process. Transformation pathways involving electrophilic substitution, hydroxylation, and nitration were proposed for 4-nitrophenol transformation in the UV/HOCl process. Wastewater matrix could significantly promote the transformation of 4-nitrophenol to 2-chloro-4-nitrophenol in UV/HOCl process. Results of this study are helpful to advance the understanding of the transformation of nitrophenolic compounds and assess the formation potential of chlorinated byproducts in HOCl and UV/HOCl disinfection processes. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the influence of UV/H2O2 advanced oxidation process on the natural organic matter content and disinfection by-products formation potential of different water matrices. Three water matrices (two natural waters and a synthetic humic acid solution) with different natural organic matter characteristics and concentrations were analysed. The carbonaceous disinfection by-products: trihalomethanes, haloacetic acids and haloketones, as well as nitrogenous disinfection by-products: haloacetonitriles and chloropicrin were investigated after chlorination. The UV/H2O2 treatment resulted in significant trihalomethane and haloacetic acids precursors removal (up to 53% and 30%, respectively) in humic acid solution in conditions ≥ 1.0 mg H2O2/mg DOC, in combination with a dose of UV irradiation ≥ 3000 mJ/cm2. Under the same reaction conditions, in natural groundwater rich in hydrophobic natural organic matter, the advanced process was less effective in DBP precursors removal. On the other hand, the advanced process was very effective in trihalomethaneprecursors removal (up to 76%) in groundwater with hydrophyilic natural organic matter. Haloketones were formed after treatment in very low concentrations. Nitrogenous disinfection by-products were only formed in the natural water containing hydrophilic organic matter, during the advanced process at 3.0 mg H2O2/mg DOC. The UV/H2O2 process resulted in negligible organic matter mineralization, but increased the brominated disinfection by-products formation in waters with low to medium bromide contents. It was concluded that under the same advanced oxidation process reaction conditions different natural organic matter structures showed different reactivities with chlorine toward the formation of the investigated disinfection by-products. [ABSTRACT FROM AUTHOR]

Introduction and methods: As part of a study on control methods of common scab disease impact on potato yield and quality, high-throughput sequencing was used to measure the effects of soil fumigant chloropicrin alone or in combination with a Bacillus species-based biostimulant on soil bacterial diversity in terms of richness and composition, as well as on soil bacterial network interactions. Results and discussion: The results showed that common scab caused significant net yield losses of more than 46.25% in potatoes of control plots (T1), while the use of the fumigant alone (T3) and the use of the fumigant with the biostimulant (T4) reduced net yield losses to less than 2.5%. These treatments also promoted gross yield increases of 23.5 cwt. acre-1 (7.06%) and 28 cwt. acre-1 (8.41%) respectively. The study found that using the soil fumigant chloropicrin significantly and persistently altered the composition of the soil bacterial community over the growing season. The modifications of the soil bacterial community induced by the inoculation of the Bacillus species-based biostimulant are distinct by the end of the growing season depending on whether the soil has been fumigated (T4) or not (T2). Interestingly, artificial network inference analysis showed that the T2 treatment had the highest number of edges and linkages, contrary to the T3 treatment that had the lowest number of edges and linkages. The fumigation alone treatment leads to a reduction in interactions, while the application of the biostimulant, in both nonfumigated and fumigated soil, results in increased interactions and a higher number of connections within a phylum or between different taxa. Furthermore, the treatment combining the fumigant and the biostimulant exhibits a moderate increase in various network properties, providing evidence for the positive effect of biostimulant inoculation on bacterial communities in fumigated soils. Our results provide a more detailed understanding of the bacterial community structure and diversity in the soil of the different treatments. Moreover, deciphering network interactions in soil bacterial communities is fundamentally important for research in soil microbial ecology of potato cropping systems. [ABSTRACT FROM AUTHOR]

Introduction: Panax notoginseng is a precious Chinese medicinal material. Soil fumigation can control soil-borne disease and overcome the continuous cropping obstacles of P. notoginseng. However, chloropicrin (CP) fumigation can kill non-target soil microorganisms and reduce microbial diversity, but the longtime impacts of CP fumigation on soil microbial are less reported. Methods: We studied the long-term effects of CP fumigation on soil microbes with high-throughput gene sequencing, and correlated the changes in the composition of microbial communities with environmental factors like soil physicochemical properties and soil enzyme activities. This study mainly focuses on the recovery characteristics of soil microbe after soil fumigation by evaluating the ecological restoration of P. notoginseng soil, its sustained control effect on plant diseases, and its promotion effect on crop growth by focusing on the CP fumigation treatment. Results: The results showed that CP fumigation significantly increased soil available phosphorus (P) to 34.6 ~ 101.6 mg/kg and electrical conductivity (EC) by 18.7% ~ 34.1%, respectively. High-throughput gene sequencing showed that soil fumigation with CP altered the relative abundance of Trichoderma, Chaetomium, Proteobacteria, and Chloroflexi in the soil while inhibiting a lot of Fusarium and Phytophthora. The inhibition rate of Phytophthora spp. was still 75.0% in the third year after fumigation. Fumigation with CP enhanced P. notoginseng's survival rate and stimulated plant growth, ensuring P. notoginseng's healthy in the growth period. The impact of fumigation on microbial community assembly and changes in microbial ecological niches were characterized using normalized stochasticity ratio (NST) and Levins' niche breadth index. Stochasticity dominated bacterial community assembly, while the fungal community was initially dominated by stochasticity and later by determinism. Fumigation with CP reduced the ecological niches of both fungi and bacteria. Conclusion: In summary, the decrease in microbial diversity and niche caused by CP fumigation could be recovered over time, and the control of soil pathogens by CP fumigation remained sustainable. Moreover, CP fumigation could overcome continuous cropping obstacles of P. notoginseng and promote the healthy growth of P. notoginseng. [ABSTRACT FROM AUTHOR]

Fumigation of soil using chloropicrin has been proven to significantly affect soil nutrient cycling, but the mechanism by which soil potassium conversion and plant uptake is promoted remains unclear. In this study, we conducted a fumigation experiment to investigate the effects of chloropicrin soil fumigation on the conversion of soil potassium post-fumigation (days 7–70), and its mechanisms, tomatos were planted in fumigated and non-fumigated soils to enable further comparisons. Results showed that the content of rapidly available potassium and available potassium decreased by 16–24% and 17–23% at day 28 respectively, when tomato was planted in chloropicrin-fumigated soils compared to the non-fumigated soils. The potassium content of tomato planted in fumigated soil was significantly higher than that planted in non-fumigated soil (30.3 vs. 21.9  mg g−1 dry weight). Chloropicrin fumigation resulted in a significant change in the soil bacterial and fungal community structures, and trigged a long-term (at least 70- day) decrease in microbial diversity. Network analysis showed that chloropicrin soil fumigation changed microbial co-occurrence patterns by decreasing bacterial total links, nodes, and average degree, and increasing fungal total links, nodes, and average degree. Chloropicrin fumigation caused significant changes in the relative abundance of Bacillus species, which are involved in potassium dissolution. Structural equation model (SEM) suggested that fumigation with chloropicrin enhanced the contribution of soil potassium to tomato growth and reduced the contribution of bacterial communities. Together, the results of our study help in understanding the crop yield enhancement mechanism of soil fumigation. [ABSTRACT FROM AUTHOR]

Introduction and methodsAs part of a study on control methods of common scab disease impact on potato yield and quality, high-throughput sequencing was used to measure the effects of soil fumigant chloropicrin alone or in combination with a Bacillus species-based biostimulant on soil bacterial diversity in terms of richness and composition, as well as on soil bacterial network interactions.Results and discussionThe results showed that common scab caused significant net yield losses of more than 46.25% in potatoes of control plots (T1), while the use of the fumigant alone (T3) and the use of the fumigant with the biostimulant (T4) reduced net yield losses to less than 2.5%. These treatments also promoted gross yield increases of 23.5 cwt. acre-1 (7.06%) and 28 cwt. acre-1 (8.41%) respectively. The study found that using the soil fumigant chloropicrin significantly and persistently altered the composition of the soil bacterial community over the growing season. The modifications of the soil bacterial community induced by the inoculation of the Bacillus species-based biostimulant are distinct by the end of the growing season depending on whether the soil has been fumigated (T4) or not (T2). Interestingly, artificial network inference analysis showed that the T2 treatment had the highest number of edges and linkages, contrary to the T3 treatment that had the lowest number of edges and linkages. The fumigation alone treatment leads to a reduction in interactions, while the application of the biostimulant, in both non-fumigated and fumigated soil, results in increased interactions and a higher number of connections within a phylum or between different taxa. Furthermore, the treatment combining the fumigant and the biostimulant exhibits a moderate increase in various network properties, providing evidence for the positive effect of biostimulant inoculation on bacterial communities in fumigated soils. Our results provide a more detailed understanding of the bacterial community structure and diversity in the soil of the different treatments. Moreover, deciphering network interactions in soil bacterial communities is fundamentally important for research in soil microbial ecology of potato cropping systems.

• HO• and RNS during VUV photolysis of NO3− contributed to TCNM formation. • Solution pH, chloride and bicarbonate cannot effectively dimmish TCNM formation. • TCNM formation showed a linear relationship with the Hammett constant. • Newly formed 1161 nitrogen-containing compounds have higher aromaticity. • Results indicated TCNM formation risk of VUV applying in water treatment. Vacuum ultraviolet (VUV) photolysis is recognized as an environmental-friendly treatment process. Nitrate (NO 3 −) and natural organic matter (NOM) are widely present in water source. We investigated trichloronitromethane (TCNM) formation during chlorination after VUV photolysis, because TCNM is an unregulated highly toxic disinfection byproduct. In this study: (1) we found reactive nitrogen species that is generated under VUV photolysis of NO 3 − react with organic matter to form nitrogen-containing compounds and subsequently form TCNM during chlorination; (2) we found the mere presence of 0.1 mmol/L NO 3 − can result in the formation of up to 63.96 µg/L TCNM; (3) we found the changes in pH (6.0-8.0), chloride (1-4 mmol/L), and bicarbonate (1-4 mmol/L) cannot effectively diminish TCNM formation; and, (4) we established the quantitative structure-activity relationship (QSAR) model, which indicated a linear relationship between TCNM formation and the Hammett constant (σ) of model compounds; and, (5) we characterized TCNM precursors in water matrix after VUV photolysis and found 1161 much more nitrogen-containing compounds with higher aromaticity were generated. Overall, this study indicates more attention should be paid to reducing the formation risk of TCNM when applying VUV photolysis process at scale. [Display omitted]. [ABSTRACT FROM AUTHOR]

Chloropicrin (CP) is a common agricultural fumigant historically used as a chemical warfare agent and is a concern for potential use in warfare and terrorist applications. Our inability to effectively treat CP-induced injuries makes it essential to better understand CP toxicity. We set out to elucidate variables that must be understood to achieve optimal exposure conditions for in vitro investigations given that such models are important for the study of CP injury and potential therapeutics. To this end, we evaluated the effects of volatility, cell seeding density, and serum concentration of cell culture medium on CP toxicity in an immortalized human corneal epithelial cell line. We found that even with very dilute solutions, CP remained highly volatile, so much so that a 0.0019% CP solution resulted in 90% cell death at time 0, but was nearly nontoxic 45 min later. Not surprisingly, the CP-induced IL-8 response was shown to vary with cell viability in this experiment. After exposure with 0.00115% CP, cells that were 12% confluent experienced over 40% more cell death than cells exposed at 87% confluency. Exposure with the same CP dose in medium containing concentrations of fetal bovine serum (FBS) ranging from 0.1% to 15% exhibited a 17% difference in cell viability. Given that chemical toxicity can be significantly influenced by volatility, cell density, and serum content of cell culture medium, these phenomena should be explored during the development and optimization of toxicant exposure models. [ABSTRACT FROM AUTHOR]

The area used to grow high-value crops is currently decreasing because production in the same soil for many years increases soil-borne diseases that reduce crop yield and quality as well as farmer income. Soil-borne disease is effectively controlled by soil fumigation prior to planting. In this study, the five different types of soils that had been used to grow tomatoes, watermelon, cucumber, ginseng and ginger were collected from field plots with high incidence of soil-borne diseases. This experiment adopts the indoor fumigation method to conduct triple fumigation of chloropicrin(PIC), metham sodium(MS) and dimethyl disulfide(DMDS) on different soil collected to examine changes in the soil microbial community, including pathogenic fungi and bacteria and beneficial microorganisms in order to clarify the impact on the overall structure of soil microbial community while controlling complex and multiple pathogens. High-throughput gene sequencing was used to detect bacterial and fungal taxonomic changes in the treated soils. Triple fumigation significantly reduced the abundance of at least five kinds of pathogenic fungi, Fusarium oxysporum, Mortierella, Neocosmospora, Nitrospira Alternaria and significantly increased the abundance of two kinds of beneficial species, Bacillus and Trichoderma. The research result observed increases and decreases in the biodiversity and richness of beneficial and pathogenic bacteria and fungi in response to triple fumigation of soil that had been used to grow tomatoes, watermelon, cucumber, ginseng and ginger. The most significant effect was observed in the experimental field of Panax notoginseng in Wenshan, Yunnan. Triple fumigation showed good potential to decrease pathogenic bacteria and fungi in soils and improve the disease resistance of soils, and that it has a good application prospect in the field of soil disinfestation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Double‐cropping is a common practice in vegetable plasticulture whereby a second crop is planted on the same plastic bed as the first crop. Root‐knot nematodes (Meloidogyne spp.) are one of the major soilborne constraints in double‐cropped vegetables due to nematode population build‐up on the first crop. We evaluated the effect of fumigant and non‐fumigant nematicides applied on the first crop, on nematode infection and yield of the second crop in 10 field trials between 2017 and 2020. Fumigants were chloropicrin (Pic100), chloropicrin +1,3‐D (PicClor60), and non‐fumigant nematicides were oxamyl (Vydate), fluensulfone (Nimitz), fluopyram (Velum) and fluazaindolizine (Salibro). The first crop was tomato and double crops were cucumber, squash, zucchini, and cantaloupe. RESULTS: Fumigation with chloropicrin on the first crop increased root‐knot nematode damage on the double‐crop at the end of the season in seven trials, while the opposite was noted in one trial, and no difference was noted in two trials. Fumigation with chloropicrin+1,3‐D resulted in root‐knot nematode damage less than chloropicrin but more than non‐fumigated plots. Cucurbit yield was greater in non‐fumigated beds in four trials, and in chloropicrin‐treated beds in two trials. Fluensulfone reduced root‐knot nematode damage on the second crop in five out of 10 trials. CONCLUSION: Our results indicate that chloropicrin applied on the tomato crop may lead to increased root‐knot nematode damage on the double crop. More research is needed to understand the processes behind this, but it is possibly related to a reduction in natural nematode soil suppressiveness due to the broad‐spectrum fungicidal activity of chloropicrin. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Florida's strawberry industry has been facing an emerging threat after several outbreaks of an aggressive Neopestalotiopsis sp. affecting fruit, leaf, and crown caused severe yield losses. Our studies found Neopestalotiopsis sp. can survive from one production season to the next on crop debris in soil, which led us to evaluate the effect of fumigants on resident inoculum in strawberry crowns and soil. Different rates of 1,3-dichloropropene, chloropicrin, and metam potassium were applied to pasteurized soil inside glass jars containing infected strawberry crowns. Soil samples were taken after broadcast and bed fumigation treatments with a combination of 1,3-dichloropropene/chloropicrin at ratios of 63:35 were applied at four commercial fields. Crowns and soil samples were processed and plated on a semi-selective medium for Neopestalotiopsis spp. and colony-forming units (CFU) were counted 5 days after plating. CFU counts in crowns treated with 1,3-dichloropropene, chloropicrin, and metam potassium decreased significantly as rates increased and were described by exponential decay models. CFUs were not recovered in most of the soil samples from fumigated strawberry beds after broadcast or bed fumigation. However, CFUs were found in non-fumigated row middles between fumigated beds which can serve as a source of inoculum to start new epidemics. Chloropicrin, 1,3-dichloropropene, and metam potassium were effective on reducing Neopestalotiopsis spp. inoculum in strawberry crowns and soil, providing new evidence on the fungicidal activity of 1,3-dichloropropene. Broadcast fumigation with 1,3-dichloropropene/chloropicrin at ratios of 63:35 could potentially be used to reduce inoculum of Neopestalotiopsis sp. in severely infested fields.

Halonitromethanes (HNMs) as one typical class of nitrogenous disinfection byproducts (DBPs) have been widely found in drinking water and are receiving more and more attentions because of their high cytotoxicity, genotoxicity, and developmental toxicity. However, the effects of HNMs exposure on the intestinal tract and intestinal flora remain unknown. This study comprehensively determined the effects of trichloronitromethane, bromonitromethane, and bromochloronitromethane exposure on the intestinal tract and intestinal flora. Results showed that the three HNMs induced intestinal oxidative stress and inflammatory response. Further, HNMs exposure could change the diversities and community structure of intestinal flora, thereby triggering intestinal flora dysbiosis, which might be associated with the intestinal damage such as oxidative stress and inflammation. The intestinal flora dysbiosis was accompanied with mark alterations in function of intestinal flora, such as carbohydrate, lipid, and amino acid metabolisms. This research provides a new insight into studying the toxicity of HNMs exposure based on intestinal flora, which will further improve the health risk assessment of DBPs in drinking water. [ABSTRACT FROM AUTHOR]

BACKGROUND: The effectiveness of metam potassium, 1,3‐dichloropropene, chloropicrin, and different ratios of 1,3‐dichloropropene and chloropicrin on the reduction of natural and artificial inoculum of Macrophomina phaseolina were investigated in laboratory and field experiments. Additionally, a multivariate meta‐analysis with data from six field trials conducted in Florida from 2012 to 2018 was performed. RESULTS: In small‐plot field experiments using drip stakes, the highest rate (468 L ha−1) of metam potassium was most effective in controlling M. phaseolina in infected crowns buried at 15.2 cm from the point of fumigant injection, whereas none of the rates was able to reduce inoculum buried at 30.5 cm. In closed‐container experiments, use of the highest rate of 1,3‐dichloropropene (168 kg ha−1) resulted in the highest level of pathogen control. Different rates of chloropicrin also reduced inoculum when compared to the non‐treated control. 1,3‐dichloropropene + chloropicrin at different ratios were also highly effective in controlling M. phaseolina. Results from the meta‐analysis of open‐field experiments indicated that metam potassium and 1,3‐dichloropropene + chloropicrin (63:35, v:v) treatments were significantly more effective in reducing M. phaseolina than the 1,3‐dichloropropene + chloropicrin (39:60, v:v) treatment; however, metam potassium was not as effective at the side of the beds. CONCLUSION: 1,3‐dichloropropene alone and in mixture with chloropicrin were more effective in reducing inoculum of M. phaseolina than chloropicrin alone, indicating the fungicidal efficacy of 1,3‐dichloropropene. Formulation with higher 1,3‐dichloropropene concentration performed better than the formulation with higher chloropicrin concentration in field trials. Metam potassium was effective when applied at the highest rate, but with limited lateral movement perpendicular to the drip irrigation line. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Soil disinfestation with steam was evaluated as an alternative to fumigation. Following soil disinfestation, plant health has traditionally been measured using plant size and yield. Plant health can be measured in a timely manner more efficiently, more easily and non-destructively using image analysis. We hypothesized that plant health could be quantified and treatments can be differentiated using an RGB (Red, Green, Blue) image analysis program, particularly by observing the greenness of plant leaves. However, plant size or the proportion of green area could be unreliable due to plant loss and camera's position and angle. To this end, we decided to evaluate plant health by analyzing the RGB codes associated with the green color only, which detects the chlorophyll reflectance and nutrient status, noting that the degree of greenness within the green-leaf-area was not affected by the plant size. We identified five RGB codes that are commonly observed in the plant leaves and ordered them from dark green to light green. Among the five RGB codes, the relative percentage covered by the darkest green to the lightest green was significantly different between the steam and chloropicrin treatments and the control, and it was not significantly different between the steam and chloropicrin treatments. Furthermore, the result was correlated with the total yield, and the trend observed in the first year was replicated in the second year of this experiment. In this study, we demonstrate that the RGB image analysis can be used as an early marker of the treatment effect on the plant health and productivity. [ABSTRACT FROM AUTHOR]

• UV/PMS and PMS-UV contributed similar SMX removal but different DBP formation potentials. • PMS-UV with a short time interval reduced TCNM formation risk. • High PMS dose in PMS-UV increased TCNM formation risk obviously. • PMS-UV in alkaline conditions enhanced SMX removal and reduced DBP risk except TCM. UV/peroxymonosulfate (UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole (SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product (DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane (TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief (5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5–1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation. [Display omitted]. [ABSTRACT FROM AUTHOR]

• DIN may promote, inhibit, or not alter N-DBP formation depending on many influencing factors. • Nitrite and ammonia usually enhance TCNM and NDMA formation, but exceptions exist. • Nitrate promotes HNM in UV processes, but otherwise does not affect N-DBP formation. • Chloramine can increase HANs, HNMs, NAs, and HAcAms formation. • Both DIN and DON can be nitrogen sources of N-DBP but their relative roles are unclear now. Aquatic nitrogenous compounds can be classified as dissolved organic nitrogen (DON) and dissolved inorganic nitrogen (DIN), including ammonia, nitrite, nitrate, and inorganic chloramines. The occurrence of nitrogenous disinfection byproducts (N-DBPs) in water, such as haloacetonitriles (HANs), halonitromethanes (HNMs), haloacaetamides (HAcAms), and nitrosamines (NAs), has attracted considerable attention due to their higher toxicity than regulated carbonaceous analogues. While numerous studies have investigated the contributions of DON to N-DBP formation, relatively fewer studies have explored DIN as N-DBP precursors, although DINs are sometimes evaluated as influencing factors. Through a literature review and data mining, this study delves into the existing body of evidence that analyze the contributions of different forms of DIN to N-DBP generation. The results showed that ammonia and nitrite can enhance trichloronitromethane (TCNM) and nitrodimethylamine (NDMA) formation in conventional chlorination and chloramination processes, nitrate can promote HNM formation in ultraviolet-based processes, and monochloramine can increase HAN, HAcAm, HNM, and NDMA formation in most disinfection scenarios. Notably, some experiments demonstrated that the yields of dichloroacetonitrile (DCAN) and TCNM can be higher from reactions involving nitrogen-free organic precursors and DIN than those involving DON and nitrogen-free disinfectant, suggesting that the relative importance of DON and DIN in forming N-DBP in real water remains unresolved. These insights thus underscore DIN as a non-negligible precursor in N-DBP formation and call for more attention to water management strategies for DIN. [Display omitted] [ABSTRACT FROM AUTHOR]

This research performs density functional theory/QTAIM calculations at the B3LYP/6-31G (d,p) and MPW1PW91/6-31G (d,p) levels to assess the interactions of chloropicrin with B12N12 fullerene-like nanocages, as well as Al and Ga doped B12N12 nanocages. The maximum adsorption energy in the B3LYP method is −110.95 kJ/mole (−91.98 kJ/mole BSSE corrected), whereas, in the MPW1PW91 method, the energy is −113.59 kJ/mole (−96.60 kJ/mole BSSE corrected), indicating that these interactions are chemisorption types. Because of the chemical interaction of the stated molecules, our analysis reveals that Al and Ga doped B12N12 has higher adsorption energy, higher charge transfer rate and a short bond gap towards adsorbate molecules, concerning pristine B12N12. The density of states (DOSs) and frontier molecular orbital (FMO) analysis revealed that a different orbital hybridisation occurs during chloropicrin adsorption, suggesting that B12N12, as well as Al and Ga doped B12N12, could be utilised as an excellent chloropicrin gas adsorbent. [ABSTRACT FROM AUTHOR]

Strawberry runners (transplants) in many regions of the world are produced in soils treated with chemical fumigants to control pathogens and weeds and meet phytosanitary requirements. Many fumigants, however, are under threat of withdrawal because of concerns over their impact on the environment (e.g., methyl bromide). The current study considered the use of microwaves for heat disinfestation of soil for field-grown runners for the first time. Results from two field experiments showed that microwave treatment reduced the survival of buried inoculum of the strawberry pathogens Fusarium oxysporum (by up to 93%) and Sclerotium rolfsii (by up to 100%) compared with untreated soil. Furthermore, the treatment reduced the subsequent growth of these pathogens in the laboratory by up to 82% and 100%, respectively. Microwave treatment also reduced the natural DNA concentration of Pythium spp. (clades I & F) in soil by up to 94% compared with untreated soil. The effect of microwave against soilborne pathogens reduced as soil depth increased. Microwave treatment reduced the emergence of weeds in field soils by up to 65% and increased runner yields by 10–37%. The effect of microwave treatment on runner yield was greater when all soil was treated, rather than when strips of soil around the mother plants were treated. Results from complimentary pot experiments showed that early strawberry growth in the glasshouse was equivalent in soils treated with microwave or the fumigant methyl bromide/chloropicrin. Furthermore, the early performance of runners sourced from field soils treated with microwave or methyl bromide/chloropicrin was equivalent. Results from the pot experiments also showed that steam treatment required 10 times more energy per mass of soil to disinfest than microwave. The limitations of microwave in the current experiments are discussed, but the capacity for the technology to disinfest field soils in an energy-efficient manner demonstrates its potential for further development as an alternative to soil disinfestation with chemical fumigants. [ABSTRACT FROM AUTHOR]

Purpose: Although soil fumigation efficiently controls soil-borne diseases, the effects of repeated soil fumigation on soil phosphorus (P) cycling are still largely unknown. Methods: In this study we conducted a field experiment to explore soil phosphorus availability in ginger fields with 0, 3, and 7 years (F0, F3, and F7) of annual chloropicrin (CP) fumigation history in Shandong Province of China. Soil samples (0–20 cm) were collected at four different times in 2019. Ginger yield, soil phosphatase (acid and alkaline) activities, and soil P fractions were measured. Results: Results showed that ginger rhizome yield was similar in F0 and F3 (70.0 t ha−1), but significantly lower in F7 (37.5 t ha−1). The acid phosphatase (AiP) activity was significantly higher in F0, while alkaline phosphatase (AlP) activity was the highest in F3. There was no significant difference in the available P (resin-P + NaHCO3-P + NaOH-P) between F0 and F7, with 33.6 to 57.5% of total P (TP), while the available P was significantly lower in F3, being less than 30% of TP. Redundancy analysis (RDA) showed that the highest pH values in F3 contributed to the lowest soil P availability there. AiP activities showed highly positive effects on the soil labile P contents. Conclusion: Results suggested that more P fertilizers are needed after 3 years of CP fumigation to avoid soil P deficiency for ginger growth. The death of ginger became the main limitation for ginger production after 7 years of CP fumigation, at which time, comprehensive agricultural practices should be considered to control ginger soil-borne diseases. [ABSTRACT FROM AUTHOR]

Chemical fumigation and biofumigation are used to reduce soil-borne diseases in agricultural production systems; however, nontargeted soil microorganisms may also be affected. This study compared the effects of chemical fumigation, either used alone or combined with an organic amendment, and biofumigation on soil bacterial community diversity and composition under controlled conditions over 160 days. Treatments included: fumigation with chloropicrin (CP), fumigation with metam sodium used alone (MS) or combined with barley plant residues (MSBR), biofumigation with mustard plant residues, addition of barley plant residues and untreated control. Biofumigation had a greater impact on bacterial diversity at early time points, transiently decreasing species evenness and yielding the most dissimilar β-diversity after 3 days. MS fumigation did not affect bacterial diversity indices; however, MSBR transiently decreased species evenness after 8 days. CP-treated soil had decreased species evenness that did not recover over time and had the most dissimilar β-diversity at the end of the incubation compared with all other treatments. This study demonstrated that CP fumigation had the greatest and most persistent impact on bacterial diversity, whereas MS fumigation and biofumigation led to transient decreases in bacterial diversity. [ABSTRACT FROM AUTHOR]

Soil disinfestation with steam has potential to partially replace fumigants such as methyl bromide, chloropicrin, and 1,3-dichloropropene because it is effective, safer to apply, and has less negative impact on the environment. Here, we compared the efficacy of steam and steam + mustard seed meal (MSM) to chloropicrin on soil disinfection, plant growth, and fruit yield in a strawberry (Fragaria ×ananassa) fruiting field. The MSM was applied at 3368 kg·ha−1 before the steam application. Steam was injected into a 3-m-wide reverse tiller that was set to till 30 to 40 cm deep. Soil temperatures at depths of 10, 20, 25, and 35 cm were monitored. Steam and steam + MSM treatments reduced the viability of purslane seeds and nutsedge tubers, microsclerotia density of Verticillium dahliae, propagule density of Pythium ultimum, cumulative weed densities, and biomass compared with the nontreated control. Moreover, the steam application was as efficacious as chloropicrin on these pests. The growth and fruit yield of strawberries grown on soils previously treated with the steam and steam + MSM treatments were similar to those in the chloropicrin treatment and were higher than those in the nontreated control. Our study indicated that steam, steam + MSM, and chloropicrin are equally effective at suppressing weeds and soilborne pathogens. These results suggest that the steam and steam + MSM treatment can be a practical alternative for soil disinfestation in conventional and organic strawberry fields.

Background: Soil fumigation is widely used as an effective way to control soil‐borne diseases and increase crop yield. Fumigants may also affect the bioavailability and mobility of soil trace elements (STEs) due to the inhibitory and biocidal effects of soil microorganisms. Aims: Quantification of STEs fractions after fumigation would help us in understanding the role of fumigants on soil environment and provide valuable evidence on the explanation of the "fertilizer effect" of soil fumigants. The overall objective was to quantify the effects of soil fumigation on three main chemical fractions of nine STEs. Methods: Effects of chloropicrin (PIC), dimethyl disulfide (DMDS), dazomet (DZ) on STEs were studied in three soils with standard and high dosages of fumigants. STEs fractions were detected using a modified Community Bureau of Reference three‐stage sequential extraction procedure. Results: Results were evident in three farmland soils: (1) Among the nine elements, three fumigants had a significant impact on Mn and Co elements. Soils had a great complement to the bioavailable Mn and Co after fumigation. The content of Mn and Co in F1, the most available and transportable form for plants, significantly increased after fumigation with PIC, DMDS, and DZ. (2) Soil fumigation has an impact on Mn, Co, and other trace elements due to the process of Mn oxidation changed. Conclusions: Our study suggested that the complement of bioavailable Mn and Co could be an important factor to promote plant growth and increase crop yield after soil fumigation. [ABSTRACT FROM AUTHOR]

Chloropicrin, ethyl-bromide, and methyl-bromide are the three primary chemical malignant anatomical stuff found in poultry feeds. The risk of cancer is found in some cases for the association of this stuffs. Hence, an effective detection method is necessary for identifying this malignant stuff. Here, we have suggested a square core-based PCF sensor that is operable in the 1–2 THz regime. The well-known polymer zeonex is selected as the hosting material and the investigation is carried out by the FEM method. After completing the numerical analyses, a higher sensitivity of 94.6%, 92.7%, and 93.3% is, respectively, obtained for chloropicrin, ethyl-bromide, and methyl-bromide. Also, an imperceptible CLoss and effective material loss are obtained from this simulation. Again, the measurements of the effective area, numerical aperture, core power fraction, and propagation constant are done for the three malignant stuff. The present existing technologies confirm the manufacturing chances of this recommended sensor. Our proposed sensor can be a deft aspirant in the areas of poisonous chemical sensing along with various application areas of bio-sensing. [ABSTRACT FROM AUTHOR]

Background: Soil fumigation is widely used as an effective way to control soil‐borne diseases and increase crop yield. Fumigants may also affect the bioavailability and mobility of soil trace elements (STEs) due to the inhibitory and biocidal effects of soil microorganisms. Aims: Quantification of STEs fractions after fumigation would help us in understanding the role of fumigants on soil environment and provide valuable evidence on the explanation of the "fertilizer effect" of soil fumigants. The overall objective was to quantify the effects of soil fumigation on three main chemical fractions of nine STEs. Methods: Effects of chloropicrin (PIC), dimethyl disulfide (DMDS), dazomet (DZ) on STEs were studied in three soils with standard and high dosages of fumigants. STEs fractions were detected using a modified Community Bureau of Reference three‐stage sequential extraction procedure. Results: Results were evident in three farmland soils: (1) Among the nine elements, three fumigants had a significant impact on Mn and Co elements. Soils had a great complement to the bioavailable Mn and Co after fumigation. The content of Mn and Co in F1, the most available and transportable form for plants, significantly increased after fumigation with PIC, DMDS, and DZ. (2) Soil fumigation has an impact on Mn, Co, and other trace elements due to the process of Mn oxidation changed. Conclusions: Our study suggested that the complement of bioavailable Mn and Co could be an important factor to promote plant growth and increase crop yield after soil fumigation. [ABSTRACT FROM AUTHOR]

Fumigation is a widely applied approach to mitigate the soil-borne diseases. However, the potential effects of currently applied fumigants on ammonification remain unclear. An 84-day incubation experiment was conducted based on non-fumigated soil (CK) and fumigated soil using three common fumigants, i.e., chloropicrin (CP), 1,3-dichloropropene (1,3-D), and metam sodium (MS). The results showed that, the three fumigants all decreased the microbial C, and the largest reduction (84.7%) occurred with the application of CP. After fumigation, the microbial diversity in the CP treatment rapidly recovered, but that in the 1,3-D treatment decreased and did not recover by the end of the experiment. The application of MS showed no impact on the microbial diversity during the assay, indicating that significantly different microbial diversity can be achieved by choosing different fumigants. Furthermore, the three fumigants showed divergent effects on the enzymes involved in ammonification. The analysis showed that the enzyme variation with CP application was mainly associated with the changed microbial C and N (P

Soil chloropicrin (CP) fumigation helps to increase crop yields by eliminating soil-borne diseases which inhibit plant growth. However, little is known about the effect of the CP fumigation combined with fungicide application on plant growth and nutrient uptake. In this study, we conducted a mesocosm experiment with six treatments: CK (untreated soil), AZO1 (a single application of azoxystrobin (AZO)), AZO2 (double applications of AZO), CP (CP fumigation with no AZO), CP+AZO1 (CP combined with AZO1) and CP+AZO2 (CP combined with AZO2) to investigate the effects of CP fumigation and AZO application on ginger growth and phosphorus (P) uptake. Results showed that a single application of AZO had no significant effect on ginger height, biomass and P uptake whether treated with or without CP fumigation, whereas double applications of AZO combined with CP fumigation significantly improved ginger height and the total amount of P in root (P

Soil fumigation with chloropicrin (CP) is an effective means of overcoming continuous cropping obstacles (CCO) in Panax notoginseng and improving its yield and quality. CP fumigation can change the microbial community of soil. Therefore, a key step after CP fumigation is the rapid restoration of soil microorganisms and the promotion of beneficial microorganism proliferation as the dominant flora. In this study, continuously cropped soil of P. notoginseng was fumigated with CP, and general organic fertilizer (GOF) or microbial organic fertilizer (MOF) was used to restore soil microorganisms after fumigation. Soil physical and chemical properties, soil microorganisms, and quality of P. notoginseng were investigated. The application of MOF and GOF after CP fumigation promoted increases in soil nitrogen (9.88% and 8.21%, respectively), phosphorus (21.39% and 11.57%, respectively), potassium (7.99% and 2.75%, respectively), and the quality of P. notoginseng; it also promoted the accumulation of saponins in the main roots (23.62% and 9.12%, respectively). Application of MOF and GOF can restore the diversity of microorganisms in the soil. MOF increased the relative abundance of the beneficial soil microorganisms Glomeromycota, Mortierellomycota, Humicola and Bacillus, thereby lowering the relative abundance of the harmful Ascomycota and Fusarium relative to GOF. In summary, CP fumigation reduces the diversity of microorganisms in the soil. The addition of organic fertilizer can promote microbial diversity and increase the relative abundance of beneficial species. Moreover, the promotion effect of MOF is better than that of GOF, thereby improving soil fertility and ultimately promoting the quality and yield of P. notoginseng.

Chloropicrin is a commonly used pesticide in agricultural production. The clinical manifestations of oral poisoning patients are complex, and the lesions involve multiple organs. At present, the specific pathogenic mechanism of such poisoning is not clear, and the treatment experience is insufficient, so there are certain difficulties in clinical diagnosis, treatment and treatment. In this paper, the data of a patient with oral chloropicrin poisoning treated in Yidu Central Hospital of Weifang City in April 2023 were summarized. The patient was admitted to our hospital for treatment in time, and his condition improved after Hemopurification, methylene blue reduction, organ support, infection prevention as well as other symptomatic support. Oral chlorophenol can cause lung damage, skin and mucous membrane damage, and may have certain effects on the nervous system and kidney. Early intervention, especially blood purification, is effective.

Irradiation at far ultraviolet C (far-UVC) 222 nm by krypton chloride (KrCl*) excilamps can enhance microbial disinfection and micropollutant photolysis/oxidation. However, nitrate/nitrite, which absorbs strongly at 222 nm, may affect the formation of disinfection byproducts (DBPs). Herein, we evaluated model organic matter and real water samples and observed a substantial increase in the formation potential for trichloronitromethane (chloropicrin) (TCNM-FP), a nitrogenous DBP, by nitrate or nitrite after irradiation at 222 nm. At a disinfection dose of 100 mJ·cm -2 , TCNM-FP of humic acids and fulvic acids increased from ∼0.4 to 25 and 43 μg·L -1 , respectively, by the presence of 10 mg-N·L -1 nitrate. For the effect of nitrate concentration, the TCNM-FP peak was observed at 5-10 mg-N·L -1 . Stronger fluence caused a greater increase of TCNM-FP. Similarly, the increase of TCNM-FP was also observed for wastewater and drinking water samples containing nitrate. Pretreatment using ozonation and coagulation, flocculation, and filtration or the addition of H 2 O 2 can effectively control TCNM-FP. The formation potential of other DBPs was minorly affected by irradiation at 222 nm regardless of whether nitrate/nitrite was present. Overall, far-UVC 222 nm treatment poses the risk of increasing TCNM-FP of waters containing nitrate or nitrite at environmentally relevant concentrations and the mitigation strategies merit further research.

As an emerging class of nitrogenous disinfection by-products, halonitromethanes have caused public health concerns owing to their high toxicity. More and more attention has been paid to the new materials and technologies for the removal of halonitromethanes. In this study, a novel material, nanoscale zero-valent iron (nZVI) supported on MIL-96 (nZVI@MIL-96) with favorable stability and reusability, was synthesized and applied to the adsorption-degradation of trichloronitromethane (TCNM) in the water. The results revealed that almost all the TCNM could be removed under 20 mg/L nZVI@MIL-96 dosage with a wide temperature range. The optimum mass ratio of nZVI to MIL-96 was 1:2, and the TCNM adsorption-degradation followed a pseudo-first-order model. The coexisting ions, such as SO42–, PO43–, and NO3–, with high concentration brought adverse effects on the removal of TCNM; however, the effects of Cl– and CO32– were insignificant. The concentrations of aluminum and iron ions in water were all within the standard value after adsorption with the nZVI@MIL-96. The degradation mechanism of TCNM by nZVI@MIL-96 included two steps, namely, adsorption and degradation, and methylamine was the terminal dechlorination and denitration products. In a word, the as-prepared nZVI@MIL-96 nanoparticles demonstrated the capabilities as a material of adsorption-degradation of TCNM in the water. [ABSTRACT FROM AUTHOR]

Reductive soil disinfestation (RSD) and soil fumigant chloropicrin (SFC) are two common agricultural strategies for the elimination of soil-borne pathogens. However, the differences in soil environmental factors, soil bacterial microbiome, and root performance between SFC and RSD are poorly understood. In this study, three soil treatments, untreated control (CK), SFC with 0.5 t⋅ha–1 chloropicrin, and RSD with 15 t⋅ha–1 animal feces, were compared. We evaluated their effects on soil environmental factors, bacterial community structure, and root activity using chemical analysis and high-throughput sequencing. RSD treatment improved soil composition structure, bacterial diversity, and root performance to a greater extent. Carbon source utilization preference and bacterial community structure were strikingly altered by SFC and RSD practices. Bacterial richness, diversity, and evenness were notably lowered in the SFC- and RSD-treated soil compared with the CK-treated soil. However, RSD-treated soil harbored distinct unique and core microbiomes that were composed of more abundant and diverse potentially disease-suppressive and organic-decomposable agents. Also, soil bacterial diversity and composition were closely related to soil physicochemical properties and enzyme activity, of which pH, available Na (ANa), available Mg (AMg), available Mn (AMn), total Na (TNa), total Ca (TCa), total Cu (TCu), total Sr (TSr), urease (S-UE), acid phosphatase (S-ACP), and sucrase (S-SC) were the main drivers. Moreover, RSD treatment also significantly increased ginseng root activity. Collectively, these results suggest that RSD practices could considerably restore soil nutrient structure and bacterial diversity and improve root performance, which can be applied as a potential agricultural practice for the development of disease-suppressive soil. [ABSTRACT FROM AUTHOR]

The breakthrough time (tB) for new types of gas mask carbons exposed to chloropicrin, hydrogen cyanide and dicyan (Cl3CNO2, HCN and (CN)2) is determined. The influence of the modifiers K2CO3 and triethylenediamine (TEDA) as additives to the impregnation compositions of gas mask carbons against toxic gases has been studied. A relationship between the studied textural parameters and the detoxification of the substances has been established. [ABSTRACT FROM AUTHOR]

The breakthrough time (tB) for new types of gas mask carbons exposed to chloropicrin, hydrogen cyanide and dicyan (Cl3CNO2, HCN and (CN)2) is determined. The influence of the modifiers K2CO3 and triethylenediamine (TEDA) as additives to the impregnation compositions of gas mask carbons against toxic gases has been studied. A relationship between the studied textural parameters and the detoxification of the substances has been established. [ABSTRACT FROM AUTHOR]

• Chloropicrin (CP) exposure causes corneal injury like vesicating mustard agents. • Ex vivo rabbit corneal injury model with CP was developed for efficacy studies. • Oxygen treatment could be effective in corneal tissue preservation and wound healing. • Supersaturated oxygen emulsion (SSOE) treatment mitigated CP-induced corneal injury. • SSOE abrogated CP-induced cell death, DNA damage and inflammatory markers. With a possibility for the use of chemical weapons in battlefield or in terrorist activities, effective therapies against the devastating ocular injuries, from their exposure, are needed. Oxygen plays a vital role in ocular tissue preservation and wound repair. We tested the efficacy of supersaturated oxygen emulsion (SSOE) in reducing ex vivo corneal and keratocyte injury from chloropicrin (CP). CP, currently used as a pesticide, is a chemical threat agent like the vesicating mustard agents and causes severe corneal injury. Since our previous study in human corneal epithelial cells showed the treatment potential of SSOE (55 %), we further tested its efficacy in an ex vivo CP-induced rabbit corneal injury model. Corneas were exposed to CP (700 nmol) for 2 h, washed and cultured with or without SSOE for 24 h or 96 h. At 96 h post CP exposure, SSOE treatment presented a healing tendency of the corneal epithelial layer, and abrogated the CP-induced epithelial apoptotic cell death. SSOE treatment also reduced the CP induced DNA damage (H2A.X phosphorylation) and inflammatory markers (e.g. MMP9, IL-21, MIP-1β, TNFα). Further examination of the treatment efficacy of SSOE alone or in combination with other therapies in in vivo cornea injury models for CP and vesicants, is warranted. [ABSTRACT FROM AUTHOR]

The growing use of pesticides is a cause of major concern because it poses harm not only to the environment but to human health as well. Chloropicrin (PS) is a volatile organic compound (VOC) used as a fumigant and is hence harmful to the atmosphere and needs to be removed before it can cause any harm. Graphene-based materials have been widely used as decontaminants because of their unique structure and properties. Here we have explored the interaction of not only pristine graphene (PG) but also some of its modified forms using periodic density functional (DF) calculations with dispersion corrections (DFT-D). Several possible modes of adsorption have been explored in each case. The pesticide is only physisorbed on pristine graphene. Doping with boron leads to a further decrease in the adsorption energy, but doping with nitrogen has the opposite effect, leading to a substantial increase in the adsorption energy, but it is still physisorption with no formation of bonds. Doping with BN also leads to negligible adsorption energy. Doping with a stronger n-type dopant, Fe, was also considered, and in this case, there is chemisorption, one C-Cl bond dissociating and the Cl getting attached to the Fe atom. Finally, decoration with a small Fe4 cluster led to the strongest chemisorption, the pesticide getting completely dissociated. We also considered the effect of decreasing number of halogen atoms and change in the halogen on the adsorption on Fe4-decorated graphene. [ABSTRACT FROM AUTHOR]