Kinetics of the photolysis of pyridaben and its main photoproduct in aqueous environments under simulated solar irradiation.

The photolytic fate of pyridaben and its main photolysis product was investigated in different aqueous solutions. Results showed that the photolysis of pyridaben followed pseudo first-order kinetics or the hockey-stick model. In buffer solutions, the half-life of pyridaben was the shortest at pH 4, while the degradation rate within 24 h was the highest at pH 9. Humic acids (HA) at concentrations of 1-20 mg L-1 favored the photolysis of pyridaben while fulvic acids (FA) did not have a significant effect. Nitrate at low concentrations (0.01 mM) accelerated the photolysis and Fe(iii) at high concentrations (0.01 and 0.1 mM) significantly inhibited the photolysis. The photolysis rate of pyridaben in rainwater, tap water, and river water was significantly higher than that in distilled water. The half-lives in distilled water, rainwater, tap water, river water, and pond water were 2.36, 1.36, 1.61, 1.77, and 2.68 h, respectively. Ultra-high-performance liquid chromatography/high-resolution mass spectrometry identified M328 as a photolysis product. The degradation of M328 followed pseudo first-order kinetics in distilled water, buffer solutions and aqueous solutions fortified with HA. The half-lives of M328 were in the range of 7.07-13.95 h. These results are essential for further environmental risk assessment of pyridaben.

An overview on the green synthesis and removal methods of pyridaben.

Pyridaben is an acaricide widely used around the world to control phytophagous mites, white flies, aphids, and thrips. It is highly toxic to nontarget organisms such as predatory mites, bees, and fishes. Therefore, the occurrence and removal of pyridaben in food and the environment are worthy of concern. This mini-review focuses on pyridaben residue levels in crops, aquatic systems, and soils, as well as the green synthesis and removal of pyridaben. During the period of 2010-2022, pyridaben was reported in monitoring studies on fruits, vegetables, herbs, bee products, aquatic systems, and soils. Vegetable and agricultural soil samples exhibited the highest detection rates and residue levels. One-pot synthesis offers a green chemistry and sustainable alternative for the synthesis of pyridaben. Among traditional home treatments, peeling is the most effective way to remove pyridaben from crops. Magnetic solid-phase extraction technology has emerged as a powerful tool for the adsorption and separation of pyridaben. Photocatalytic methods using TiO2 as a catalyst were developed as advanced oxidation processes for the degradation of pyridaben in aqueous solutions. Current gaps in pyridaben removal were proposed to provide future development directions for minimizing the exposure risk of pyridaben residues to human and nontarget organisms.

Combined Experimental and Computational Study on the Transformation of a Novel 1,3,4-Oxadiazole Thioether Nematicide in Aqueous Solutions.

It has been demonstrated that Exianliuyimi (EXLYM) exhibits good nematocidal activity. As a potential nematicide, EXLYM and its transformation products (TPs) may generate emerging pollutants with hazardous effects on the ecosystem. In this study, the fate of EXLYM in aqueous solutions was investigated using experimental and theoretical approaches. Laboratory-scale experiments showed that EXLYM is hydrolytically stable. Microbial processes are primarily responsible for the oxidation of sulfur in aqueous solutions. Under simulated sunlight, the t1/2 values of EXLYM in acidic, neutral, and alkaline buffer solutions were 5.02, 3.83, and 5.55 h, respectively. Six TPs were identified using a non-target screening strategy realized by ultra-high-performance liquid chromatography coupled with Q-Exactive Orbitrap high-resolution mass spectrometry and 18O-labeling experiments. Four of these were unambiguously confirmed using authentic standards. Reactive oxygen species scavenging experiments, 18O-labeling experiments, and quantum-theoretical calculations suggested that EXLYM could degrade mainly through four pathways: sulfur oxidation, nucleophilic aromatic photosubstitution, C-S bond cleavage, and oxidative ring-opening. The proposed degradation kinetics, TPs, and transformation pathways in aqueous solutions provide valuable information on the fate of EXLYM in aquatic ecosystems and lay the foundation for further toxicological tests.

Identification of genetic variants of the IL-22 gene in association with an altered risk of COPD susceptibility.

The incidence of chronic obstructive pulmonary disease (COPD) is related to the interaction between environmental exposure and genetic factors. Far more than 15% of smokers eventually develop COPD. In addition to smoking, genetic susceptibility may be another factor in the development of COPD. IL-22 and its receptors are increased in human and experimental COPD and contribute to pathogenesis. Here, we conducted a case-control study to evaluate the association between IL-22 tag-single nucleotide polymorphisms (SNPs) and COPD risk. Four tag-SNPs (rs2227478, rs2227481, rs2227484 and rs2227485) were identified according to linkage disequilibrium (LD) analysis in 30 healthy controls. A total of 513 COPD cases and 504 controls were recruited to perform an association study between these four tag-SNPs and COPD risk. We found that the "C" allele of rs2227478T>C and the "T" allele of rs2227481C>T were obviously related to decreased COPD susceptibility. Genetic model analysis showed that rs2227478T>C and rs2227481C>T were significantly associated with a decreased risk of COPD under dominant models after adjusting for the above factors. In the recessive model, rs2227485T>C was obviously associated with decreased COPD risk. Our data showed that only rs2227485T>C was associated with a decreased COPD risk after Bonferroni correction. The eQTL analysis showed that rs2227485T>C was significantly associated with IL-22 expression. The pGL4-rs2227485-C gene reporter had a higher promoter activity than pGL4-rs2227485-T. In our study, rs2227485T>C, located in the promoter region of IL-22, was associated with a decreased risk of COPD and increased IL-22 promoter activity, suggesting that this variant might modulate COPD susceptibility.

Simple strategy for the construction of oxygen vacancies on α-MnO2 catalyst to improve toluene catalytic oxidation.

A strategy simple, safe and suitable for large scale production of α-MnO2 catalyst with high activity in VOCs oxidation is crucial for its application. The catalytic reactivity of α-MnO2 catalyst is largely related with its oxygen vacancy. Herein, we report effective construction of oxygen vacancies on α-MnO2 through simply adjusting precipitation temperature of a redox precipitation process. The key role of surface oxygen vacancies in toluene oxidation and the formation of different amount and distribution of the oxygen vacancies over the α-MnO2 catalysts were revealed by characterizations together with DFT calculations. The best catalyst (α-MnO2-60) exhibited significantly improved catalytic activity of α-MnO2 catalyst in toluene oxidation (T90 = 203 â„ƒ) and excellent water resistance. The richest surface oxygen vacancies of α-MnO2-60 contributed to its best catalytic activity, despite of its relatively lower specific surface area. This work may provide a new perspective for the rational design of high efficient VOCs catalysts.

Qualitative and Quantitative Analysis of the New Sulfone Bactericide 2-(4-Fluorophenyl)-5-(Methylsulfonyl)-1,3,4-Oxadiazole and Identification of Its Degradation Pathways in Paddy Water.

Rapid and simple methods for the determination of Jiahuangxianjunzuo (JHXJZ) in paddy water, brown rice, soil and rice straw was developed and validated. This method involved the use of ultrahigh-performance liquid chromatography equipped with photodiode array detector. The most important factor was chromatographic conditions, as identified through an orthogonal experimental design. This method showed good recoveries and precisions, thereby indicating its suitability for monitoring of JHXJZ residues in paddy water, brown rice, soil and rice straw. Furthermore, hydrolysis experiment was conducted in the laboratory under pH = 7 buffer solutions, and its degradation product was identified as 2-(4-fluorophenyl)-5-methoxy-1,3,4-oxadiazole by high-resolution mass spectrometry. JHXJZ has a major degradation pathway in the water which the OH- nucleophilic attack the C5 of 1,3,4-oxadiazole ring. Then it leaves mesyl to form intermediate 5-(4-fluorophenyl)-1,3,4-oxadiazol-2-ol and the intermediate combined with methanol formed the degradation product 2-(4-fluorophenyl)-5-methoxy-1,3,4-oxadiazole by the loss of one H2O.The degradation pathways of JHXJZ under the present indoor simulation conditions were proposed.

Determination, risk assessment and processing factors for pyridaben in field-incurred kiwifruit samples.

Field trials in six agricultural sites were carried out to investigate the dissipation and residue levels of pyridaben in kiwifruit. Each sample was extracted with acetonitrile, purified with octadecylsilane and analyzed with high-performance liquid chromatography-tandem mass spectrometry. The method had good linearity (R2 > 0.99), accuracy (recoveries of 78.53-98.00%) and precision (relative standard deviation of 0.86-6.11%). The dissipation of pyrdaben in kiwifruit followed first-order kinetics with a half-life < 8 d, and terminal residues in kiwifruit were lower than 0.5 mg/kg after 14 d of application. Risk assessment indicated that both chronic and acute dietary intake risk values were far below 100%, suggesting that pyridaben residues in kiwifruit were relatively safe to humans. Moreover, the effects of traditional household processes on kiwifruit were investigated. The processing factors (PFs) indicated that peeling and peeling-juicing processes could remove pyridaben residues from kiwifruit, and the former was more effective than the latter (PF at 0.15 vs. 0.51). Nevertheless, drying kiwifruit with an oven increased the amount of pyridaben (PF at 1.05). These results could provide guidance for the safe and reasonable use of pyridaben in agriculture and may be helpful for the Chinese government to determine maximum residue limit of pyridaben in kiwifruit.

Determination of nitenpyram dissipation and residue in kiwifruit by LC-MS/MS.

To investigate the presence of nitenpyram in kiwifruit, a field experiment was conducted in six kiwifruit producing regions in China. A modified quick, easy, cheap, effective, rugged and safe method (QuEChERS) method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the determination of nitenpyram in kiwifruit. Quantitative detection was performed by LC-MS/MS in multiple reaction monitoring (MRM) mode under positive-ion electrospray ionisation. The proposed method is linear and accurate in the range of 0.005 to 4.5 µg/mL. The recovery of nitenpyram was satisfactory (71.96-96.67%) with reasonable RSDs (9.83 %) for 0.01-4.5 mg/kg spiked levels. The limit of quantification (LOQ) was 0.01 mg/kg for nitenpyram. Nitenpyram degraded rapidly in kiwifruit with a half-life <4 days. Residues of nitenpyram were <0.01 - 0.54 mg/kg in kiwifruit 7, 14 and 21 days after spraying at six sites.

Sodium tanshinone IIA sulfonate protects against acute exacerbation of cigarette smoke-induced chronic obstructive pulmonary disease in mice.

Exacerbation of chronic obstructive pulmonary disease (COPD) is characterized by acute airway inflammation and mucus hypersecretion, which is by far the most costly aspect of its management. Thus, it is essential to develop therapeutics with low side effects for CODP exacerbation. Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA isolated as the major active component of Chinese herbal medicine Danshen. Although it possesses anti-inflammatory, anti-oxidative and anti-apoptotic properties, it remains unknown whether STS protects against COPD exacerbation. In this study, we challenged cigarette smoke (CS)-exposed mice with lipopolysaccharide (LPS), and then treated these mice with STS. We found that STS significantly ameliorated pulmonary inflammatory responses, mucus hypersecretion and lung function decline in CS-exposed mice challenged with LPS. STS treatment also significantly attenuated increased IL-6 and IL-8 releases from cigarette smoke extract (CSE)-treated human bronchial epithelial cells (16HBE) challenged with LPS. Mechanistically, STS reduced activation of ERK1/2 and NF-κB in lungs of CS-exposed mice and CSE-treated 16HBE cells challenged with LPS. Taken together, STS protects against acute exacerbation of CS-induced lung injury, which provides a promising and potential therapeutic avenue to halt acute exacerbation of COPD.

Hydrogen sulfide inhibits cigarette smoke-induced inflammation and injury in alveolar epithelial cells by suppressing PHD2/HIF-1α/MAPK signaling pathway.

Chronic obstructive pulmonary fibrosis (COPD) is a chronic and fatal lung disease with few treatment options. Sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2S), was found to alleviate cigarette smoke (CS)-induced emphysema in mice, however, the underlying mechanisms have not yet been clarified. In this study, we investigated its effects on COPD in a CS-induced mouse model in vivo and in cigarette smoke extract (CSE)-stimulated alveolar epithelial A549 cells in vitro. The results showed that NaHS not only relieved emphysema, but also improved pulmonary function in CS-exposed mice. NaHS significantly increased the expressions of tight junction proteins (i.e., ZO-1, Occludin and claudin-1), and reduced apoptosis and secretion of pro-inflammatory cytokines (i.e., TNF-α, IL-6 and IL-1ß) in CS-exposed mouse lungs and CSE-incubated A549 cells, indicating H2S inhibits CS-induced inflammation, injury and apoptosis in alveolar epithelial cells. NaHS also upregulated prolyl hydroxylase (PHD)2, and suppressed hypoxia-inducible factor (HIF)-1α expression in vivo and in vitro, suggesting H2S inhibits CS-induced activation of PHD2/HIF-1α axis. Moreover, NaHS inhibited CS-induced phosphorylation of ERK, JNK and p38 MAPK in vivo and in vitro, and treatment with their inhibitors reversed CSE-induced ZO-1 expression and inflammation in A549 cells. These results suggest that NaHS may prevent emphysema via the suppression of PHD2/HIF-1α/MAPK signaling pathway, and subsequently inhibition of inflammation, epithelial cell injury and apoptosis, and may be a novel strategy for the treatment of COPD.

Effects of mineral oil spray additives on the distribution and dissipation kinetics of pyraclostrobin and azoxystrobin in banana leaves, fruits, and soil.

Using LC-MS/MS, a rapid and sensitive method for the simultaneous determination of pyraclostrobin and azoxystrobin residues in banana matrices (leaf and whole banana) and soil was established. The samples were extracted using acetonitrile and purified through C18 dispersive solid-phase extraction. The average recovery of the analytes in various matrices was in the range of 77.3%-103.9% with an RSD range of 0.9%-9.5%. The initial deposition amounts of pyraclostrobin and azoxystrobin at 2 h in the banana leaves of the mineral oil group were 1.43 and 1.31 times in Guangxi, and 2.10 and 1.81 times in Hainan for the water group, whereas those in the soil of the water group were 3.45 and 3.03 times in Guangxi, and 2.14 and 3.48 times in Hainan for the mineral oil group. The half-lives in the leaves and soil of the mineral oil group were not remarkably different from those of the water group. The terminal residue of the analytes on the whole banana was <0.02 mg/kg at 14 days after application from the two sites. The results of this work may indicate and promote the safety of using pyraclostrobin and azoxystrobin in banana production, especially with mineral oil spray adjuvants.

Carbene-Catalyzed Enantioselective Addition of Thioamides to Bromoenals for Access to Thiazinone Heterocycles.

A carbene-catalyzed reaction between α-bromoenals and thioamides was developed. Key steps include enantioselective 1,4-addition of thioamide sulfur atoms to α,ß-unsaturated acyl azolium intermediate. Subsequent intramolecular annulation eventually affords thiazinone heterocycles with high optical purities. The introduction of Lewis acid additives such as Cu(OTf)2 to this NHC catalytic reaction could provide small but consistent improvements to reaction enantioselectivities.

Enantioselective Degradation and Chiral Stability of Glufosinate in Soil and Water Samples and Formation of 3-Methylphosphinicopropionic Acid and N-Acetyl-glufosinate Metabolites.

Two enantiomers of glufosinate were separated under reverse-phase conditions on a chiral crown stationary phase (CROWNPAK CR(+)). An efficient and reliable chiral analytical method was developed to determine the glufosinate enantiomers and two metabolites in soil and water samples using high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS). The linearities of the matrix-matched calibration curves in five water and four soil samples were good with a correlation coefficient R2 > 0.998, and the mean recoveries were 85.2-100.4%, with relative standard deviations of 1.0-7.1%. l-Glufosinate was degraded faster than d-glufosinate in four nonsterile natural soil and two nonsterile natural water samples. The degradation half-lives of the enantiomers ranged from 3.4 to 33.0 days in the soil samples, but glufosinate was stable in the five water samples, less than 22% of the applied substance degraded at the end of the experiment (100 days). Degradation in sterile soil was not enantioselective. The two enantiomers were configurationally stable in the four soil and five water samples. In most cases of glufosinate degradation in soils, the percentage of 3-methylphosphinicopropionic in relation to the parent was higher than that of N-acetyl-glufosinate. l-Glufosinate was preferentially degraded in the four soils, and formation of 3-methylphosphinicopropionic acid and N-acetyl-glufosinate was enantiomer dependent.

Deposition amount and dissipation kinetics of difenoconazole and propiconazole applied on banana with two commercial spray adjuvants.

A rapid and sensitive method for the simultaneous determination of difenoconazole and propiconazole residues in banana matrices was established using GC-MS/MS. The average recovery rates of difenoconazole and propiconazole from various matrices ranged from 76.7% to 94.9%. The relative standard deviation was between 0.9% and 7.4%. The effect of adding organosilicon and mineral oil adjuvants after being applied to the residues of difenoconazole and propiconazole in banana leaves was examined. The initial deposition amount 2 hours after the adjuvant treatment with organosilicon and mineral oil was 1.22-2.13 times higher than that after water treatment. After adding the two spray adjuvants, the residues of the two pesticides at 2 hours on three samples followed the order leaves > soil > fruit. The degradation half-lives of the two pesticides were in the range of 1.91-7.30 days for all the three treatments in two typical banana-growing areas in China. The degradation half-lives of the two pesticides in the water treatment group and the mineral oil treatment group were similar. However, organosilicon could apparently increase the half-life of difenoconazole on banana leaves. The final levels of difenoconazole and propiconazole residues on whole banana fruits were ≤0.1 mg kg-1 (MRL) 14 days after application. The results of this work may aid the safe use of difenoconazole and propiconazole in banana production, especially when used with organosilicon and mineral oil adjuvants.

Hydrolysis and Photolysis Kinetics, and Identification of Degradation Products of the Novel Bactericide 2-(4-Fluorobenzyl)-5-(Methylsulfonyl)-1,3,4-Oxadiazole in Water.

Hydrolysis and photolysis kinetics of Fubianezuofeng (FBEZF) in water were investigated in detail. The hydrolysis half-lives of FBEZF depending on pH, initial concentration, and temperature were (14.44 d at pH = 5; 1.60 d at pH = 7), (36.48 h at 1.0 mg L-1; 38.51 h at 5.0 mg L-1; and 31.51 h at 10.0 mg L-1), and (77.02 h at 15 °C; 38.51 h at 25 °C; 19.80 h at 35 °C; and 3.00 h at 45 °C), respectively. The photolysis half-life of FBEZF in different initial concentrations were 8.77 h at 1.0 mg L-1, 8.35 h at 5.0 mg L-1, and 8.66 h at 10.0 mg L-1, respectively. Results indicated that the degradation of FBEZF followed first-order kinetics, as the initial concentration of FBEZF only had a slight effect on the UV irradiation effects, and the increase in pH and temperature can substantially accelerate the degradation. The hydrolysis Ea of FBEZF was 49.90 kJ mol-1, which indicates that FBEZF belongs to medium hydrolysis. In addition, the degradation products were identified using ultra-high-performance liquid chromatography coupled with an Orbitrap high-resolution mass spectrometer. One degradation product was extracted and further analyzed by ¹H-NMR, 13C-NMR, 19F-NMR, and MS. The degradation product was identified as 2-(4-fluorobenazyl)-5-methoxy-1,3,4-oxadiazole, therefore a degradation mechanism of FBEZF in water was proposed. The research on FBEZF can be helpful for its safety assessment and increase the understanding of FBEZF in water environments.

Residual level of dimethachlon in rice-paddy field system and cooked rice determined by gas chromatography with electron capture detector.

In this study, a modified quick, easy, cheap, effective, rugged and safe method coupled with gas chromatography with electron capture detection was established to determine dimethachlon residues in paddy soil, rice husk, rice straw, brown rice and cooked rice. The limits of quantification of dimethachlon were 0.01 mg/kg for paddy soil, brown rice and cooked rice and 0.02 mg/kg for rice straw and rice husk. The mean recoveries were in the range 78.59-104.7% with relative standard deviation values of <10% for dimethachlon in the five matrices. For field experiments, the final residues of dimethachlon in paddy soil were < 0.05 mg/kg and were < 1.21 mg/kg in rice straw from six sites. The final residues of dimethachlon in the brown rice at 21, 28 and 35 days after spraying from six sites were 0.08-7.58 mg/kg, and 0.16-30.1 mg/kg in rice husk. Our six test sites covered the main rice-producing areas of China. The routine rice cooking process of a Chinese family could apparently increase the removal of dimethachlon in rice compared with brown rice, and the reduction ratios were > 96%.

Simultaneous determination and method validation of clethodim and its metabolites clethodim sulfoxide and clethodim sulfone in tobacco by LC-MS/MS.

A simple method was developed and validated for the simultaneous determination of clethodim, clethodim sulfoxide, and clethodim sulfone in soil and tobacco by liquid chromatography with tandem mass spectrometry. The three target compounds were extracted from tobacco and soil with acetonitrile, and the extracts were purified using octadecyl silane. The proposed method showed satisfactory linearity (R2 ≥ 0.9973) for the target compounds. The limits of detection and quantitation of the three analytes in all matrices were 0.024-0.06 and 0.08-0.2 mg/kg, respectively. The recovery was tested in blank soil and tobacco leaf samples and calculated to be 74.8-104.4% with relative standard deviations of 1.9-12.1%. The developed method was successfully applied to the analysis of residues of clethodim, clethodim sulfoxide and clethodim sulfone in real soil and tobacco samples. The results indicated that the developed method can meet the requirements for the analysis of trace amounts of all three analytes in soil and tobacco.

[Simultaneous determination of pyraclostrobin and thiophanate-methyl and its metabolite carbendazim residues in soil and citrus by QuEChERS-liquid chromatography- tandem mass spectrometry].

A QuEChERS-liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the determination of pyraclostrobin, thiophanate-methyl and its metabolite carbendazim in soil and citrus. The samples were extracted with methanol or acetonitrile, purified by primary secondary amine (PSA), then separated by LC, detected in multiple reaction monitoring (MRM) mass spectrometry mode via positive electrospray ionization. The analytes were quantified by matrix-matched standard solutions with external standard method. The limits of quantification (LOQs) of pyraclostrobin, thiophanate-methyl and carbendazim in different matrices were 5.8-7.0 µg/kg, 9.3-14.1 µg/kg and 2.1-2.6 µg/kg, respectively. For all the samples, the spiked recoveries ranged from 75.48% to 109.18%, and the relative standard deviations (RSDs) were 0.60%-5.11% (n=5). The method is quick, easy, effective, sensitive and accurate. The matrix-matched calibration solutions can efficiently compensate matrix effects of the pyraclostrobin, thiophanate-methyl and carbendazim in LC-MS/MS analysis. The established method can be applied to the residue analysis of the real samples of soil, citrus peel, citrus pulp and citrus fruits.

Determination of Dinotefuran and Its Metabolites in Orange Pulp, Orange Peel, and Whole Orange Using Liquid Chromatography-Tandem Mass Spectrometry.

Determination of the polar characteristics of dinotefuran and metabolite residues in orange matrixes (orange pulp, orange peel, and whole orange) is difficult. Thus, the purpose of the present study was to develop an extraction method for the determination of dinotefuran and its metabolites in oranges by using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Matrix suppression effects were observed for all analytes in the orange matrixes. The proposed method displayed satisfactory linearity (R2 ≥ 0.9856) for the target molecules. The LODs were 0.03-0.10 mg/kg, whereas LOQs were 0.08-0.40 mg/kg for dinotefuran and its metabolites. Recoveries were 79.1-98.7% with RSD values <20% for all analytes in the orange matrixes. The proposed method was used to authenticate the samples and dinotefuran residues observed in field-incurred orange matrixes. The results of the proposed method could help the Chinese government establish maximum residue limits for dinotefuran in oranges and promote the safe and proper use of dinotefuran dosages in orange trees.

Drug Interactions with Angiotensin Receptor Blockers: Role of Human Cytochromes P450.

BACKGROUND: Angiotensin receptor blockers (ARBs) are the most recent class of agents for the treatment of hypertension. However, ARBs may cause a low incidence of headache, upper respiratory infection, back pain, muscle cramps, fatigue, dizziness, and many other side effects. In some cases, such toxicity is associated with pharmacokinetic alterations. METHODS: The cytochrome P450 (CYP) enzyme system plays an important role in a lot of clinically important pharmacokinetic drug interactions. To identify relevant studies on drug-drug and food-drug pharmacokinetic interactions with the ARBs, a literature search of Google Scholar was performed from January 1994 to June 2015, with the following keywords: 'losartan', 'valsartan,' 'candesartan,' 'irbesartan,' 'telmisartan,' 'eprosartan,' 'olmesartan,' and 'azilsartan', combined with the keyword 'pharmacokinetic interactions' and 'CYP'. RESULTS: Based on the literatures published, it has been demonstrated that pharmacokinetic interactions of losartan with other agents are mainly via CYP2C9- and CYP3A4-mediated, the role played by CYP enzyme system in the metabolism of valsartan, candesartan, irbesartan, and azilsartan appears modest, and cytochrome P450 system has no influence on the metabolism of telmisartan, eprosartan, olmesartan. Therefore, according to these pharmacokinetic findings, no dosage adjustment is recommended when eprosartan, telmisartan and olmesartan are combined with other pharmacological agents in patients with hypertension. CONCLUSION: This review summarize the available data on cytochrome P450 - related drug-drug interactions reported in the literature for the eight ARBs. Knowledge of the pharmacokinetic properties of the ARBs should allow the avoidance of the majority of drug interactions without compromising therapeutic benefits.