Assessment of urinary aromatic amines in Brazilian pregnant women and association with DNA damage: Influence of genetic diversity, lifestyle, and environmental and socioeconomic factors.

Aromatic amines (AAs) are polar organic chemicals with a wide environmental distribution originating from various sources, such as tobacco smoke, diesel exhaust, and dermal absorption from textile products with azo dyes. The toxicity profile of AAs is directly related to the amino group's metabolic activation and the generation of the reactive intermediate, forming DNA adducts and potential carcinogenicity. Urinary levels of 8-hydroxy-2'-deoxyguanosine (8OHdG) are an important biomarker of DNA damage. Since AAs have been shown to cross the placental barrier, being a risk factor for adverse birth outcomes, prenatal exposure is a great public health concern. The present study aimed to measure the urinary levels of 58 AAs in Brazilian pregnant women (n = 300) and investigated the impact of this exposure on DNA damage by quantifying 8OHdG levels. The influence of tobacco smoke exposure and dermal absorption of AAs by clothes on urinary levels was also assessed. The results showed a 100% detection rate for eight AAs, two of them regulated by the European Union (2,6-dimethylaniline and 2,4-diaminotolune). Hundreds of AAs may be derived from aniline, which here showed a median of 1.38 ng/mL. Aniline also correlated positively with 2,6-dimethylaniline, p-aminophenol, and other AAs, suggesting exposure to multiple sources. The present findings suggest that both tobacco smoke and dermal contact with clothes containing azo dyes are potential sources that might strongly influence urinary levels of AAs in Brazilian pregnant women. A multiple regression linear model (R2 = 0.772) suggested that some regulated AAs (i.e., 2-naphthylamine and 4-aminobiphenyl), nicotine, smoke habit, age, and Brazilian region could induce DNA damage occurrence, increasing the levels of 8OHdG. Given the limited available data on human exposure to carcinogenic AAs, as well as the lack of toxicological information on those non-regulated, further studies focused on measuring their levels in human fluids and the potential exposure sources are clearly essential.

Bromethalin Exposure and Possible Toxicosis in a Bald Eagle (Haliaeetus leucocephalus).

A free-living Bald Eagle (Haliaeetus leucocephalus) displayed acute onset neurologic signs. Postmortem analysis of adipose tissue identified desmethylbromethalin, the active metabolite of bromethalin. Antemortem signs, detection of desmethylbromethalin, and results of other diagnostics support the possibility of secondary bromethalin toxicosis. Investigation of bromethalin's potential risk to wildlife is critically needed.

Quantification of short-chain fatty acids in human stool samples by LC-MS/MS following derivatization with aniline analogues.

The gut microbiome produces a range of short chain fatty acids (SCFA) crucially linked with diet and nutrition, metabolism, gastrointestinal health and homeostasis. SCFA are primarily measured using gas or liquid chromatography-mass spectrometry (LC/MS) after undergoing chemical derivatization. Here we assess the merits of a derivatization protocol using aniline and two aniline analogues (3-phenoxyaniline and 4-(benzyloxy)aniline) for the targeted LC-MS/MS quantification of nine SCFA (acetic, propionic, butyric, valeric, caproic acid, isobutyric, isovaleric, 2-methylbutyric, and 2-ethylbutyric acid). Evaluation of product ion spectra and optimization of MS detection conditions, provided superior detection sensitivity for 3-phenoxyaniline and 4-(benzyloxy)aniline compared to aniline. We developed a facile SCFA derivatization method using 3-phenoxyaniline under mild reaction conditions which allows for the simultaneous quantification of these SCFA in human stool samples in under eleven minutes using multiple reaction monitoring LC-MS/MS. The method was successfully validated and demonstrates intra- and inter-day accuracy (88.5-103% and 86.0-109%) and precision (CV of 0.55-7.00% and 0.33-9.55%) with recoveries (80.1-87.2% for LLOQ, 88.5-93.0% for ULOQ) and carry-over of (2.68-17.9%). Selectivity, stability and matrix effects were also assessed and satisfied validation criteria. Method applicability was demonstrated by analysing SCFA profiles in DNA-stabilized human stool samples from newly diagnosed colorectal cancer patients prior to surgery. The development of this improved method and its compatibility to measure SCFAs from DNA-stabilized stool will facilitate studies investigating the gut microbiome in health and disease.

Comparative evaluation of three methylene dianiline isomers in the bacterial reverse mutation assay, the in vitro gene mutation test, and the in vitro chromosomal aberration test.

4,4'-MDA is classified as a genotoxic carcinogen based on numerous in vitro and animal data. The consequential assumption that a safe threshold does not exist is not only applied to 4,4'-MDA but also to its structural isomers and impurities 2,2'- and 2,4'-MDA in the absence of substance-specific data. This constitutes a problem in human risk assessments for all three substances as the inherent risks of 2,2'- and 2,4'-MDA and their contribution as impurities to that of 4,4'-MDA are essentially unknown. A comparative in vitro genotoxicity dataset consisting of the bacterial reverse mutation (Ames) test and the chromosomal aberration test in human lymphocytes (both performed according to the current OECD Guidelines) was generated for all three isomers. Furthermore, an in vitro gene mutation test in Chinese hamster ovary (CHO) cells (HPRT locus assay) was conducted with 2,4'-MDA. The results indicate differences regarding the genotoxic mechanism and potential, respectively, between the three structures and suggest that the no-threshold assumption for 4,4'-MDA may not be appropriate for 2,2'- and 2,4'-MDA.

Assessment of the migration of perfluorinated compounds and primary aromatic amines from PTFE-coated non-stick cookware marketed in Turkey.

Two perfluorinated compounds (PFCs) and 17 different primary aromatic amines (PAAs) were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in migrants from 35 cookware samples marketed in Turkey. Among PFCs, only PFOA was identified in 6 samples. Only two components among PAAs, namely aniline (ANL) and 4,4'-methylenedianiline (4,4'-MDA), were detected in analyzed samples. Although aniline was detected in all samples, 4,4'-MDA was detected in only 4 samples. The effects of simulant volume, temperature, and repeated use on the release of these migrants from non-stick cookware were investigated. Three simulant volumes (200, 500, and 1000 mL) were used in migration tests. PFCs and PAAs were identified in simulants at 200 and 500 mL. The increase in the amount of simulant caused a decrease in the concentration of these migrants. The lowest migration values were observed in the samples at consecutive usage cycles. PFCs and PAAs exhibited the highest migration ability with increasing temperature.

Quantification of Osimertinib and Metabolite-Protein Modification Reveals Its High Potency and Long Duration of Effects on Target Organs.

Covalent drugs are newly developed and proved to be successful therapies in past decades. However, the pharmacokinetics (PK) and pharmacodynamic (PD) studies of covalent drugs now ignore the drug and metabolite-protein modification. The low abundance of modified proteins also prevents its investigation. Herein, a simple, selective, and sensitive liquid chromatography-mass spectrometry (LC-MS)/MS quantitative method was established based on the mechanism of a drug and its metabolite-protein adducts using osimertinib as an example. Five metabolites with covalent modification potential were identified. The drug and its metabolite-cysteine adducts released from modified proteins by a mixed hydrolysis method were developed to characterize the level of the modified proteins. This turned the quantitative objects from proteins or peptides to small molecules, which increased the sensitivity and throughput of the quantitative approach. Accumulation of protein adducts formed by osimertinib and its metabolites in target organs was observed in vivo and long-lasting modifications were noted. These results interpreted the long duration of the covalent drugs' effect from the perspective of both parent and the metabolites. In addition, the established method could also be applied in blood testing as noninvasive monitoring. This newly developed approach showed great feasibility for PK and PD studies of covalent drugs.

Determination of primary aromatic amines from cooking utensils by capillary electrophoresis-tandem mass spectrometry.

This paper describes a fast, sensitive, environment-friendly method for the determination of 19 primary aromatic amines (PAAs) in cooking utensils by capillary zone electrophoresis coupled with tandem mass spectrometry. The best electrophoretic separation of PAAs was obtained in 0.1 mol l-1 formic acid (pH 2.4) as the background electrolyte, fused silica capillary (67 cm) with a run time below 6 min. The proposed method presented a linear calibration with correlation coefficients higher than 0.99 and reproducibility in a range of 1-25%. Limits of detection were in the range of 0.2-1.3 µg kg-1 and recoveries were in a range of 85-120% for all the PAAs. The validated method was employed to determine PAAs on 36 samples of cooking utensils using acetic simulant. The results showed that 4,4'-diaminodiphenylmethane and aniline being the most frequently found PAAs in these samples and 28% of cooking utensils were not compliant.

Na-Ln Heterometallic Coordination Polymers: Structure Modulation by Na+ Concentration and Efficient Detection to Tetracycline Antibiotics and 4-(Phenylazo)aniline.

On the basis of the lanthanide metalloligand [Ln(ODA)3]3- (H2ODA = oxydiacetic acid), three new Na-Ln heterometallic coordination polymers, [Ln(ODA)3Na2]n [Ln = Eu (1) and Gd (2)] and [Tb(ODA)3Na3(H2O)2]n (3), had been assembled by adjusting the concentration of Na+ ions in the reaction system. The investigations of fluorescence sensing showed that 1 could be a ratiometric probe to detect tetracycline (TC) and oxytetracycline (OTC) with high sensitivity and low detection limits, 71.92 ppb for the former and 45.54 ppb for the latter, and 3 could selectively sense 4-(phenylazo)aniline through the turn-off pathway with 14.59 ppb of detection limits. Moreover, the competing and circulating experiments indicated that both 1 and 3 had satisfactory antiinterference and recyclability for the corresponding analytes. All of these results implied that 1 and 3 should be potential fluorescent sensors for the detection of TC/OTC and 4-(phenylazo)aniline, and the possible sensing mechanism had also been discussed in depth.

A highly specific and sensitive indirect competitive monoclonal ELISA for the detection of brombuterol in animal feed, swine urine, pork and liver samples.

Brombuterol, a new ß-adrenergic agonist to enhance animal growth and increase feeding efficiency, is forbidden as an additive in animal feed for livestock production due to its adverse effects on consumers. In this study, a highly specific and sensitive monoclonal antibody was obtained and an indirect competitive monoclonal ELISA was developed to detect brombuterol, with an IC50 value of 0.1 µg/kg (µg/L) and no cross-reactivity to other structurally related ß-adrenergic agonists. The average recovery of brombuterol using the icELISA method ranged from 72.9% to 106.4% with the coefficient of variation lower than 18.9%, which was determined by analysing spiked animal feed, swine urine, pork and liver samples (n = 5). Finally, the icELISA gave results having a good correlation with those obtained by liquid chromatography-tandem mass spectrometry. These results demonstrated that the developed icELISA for the detection of brombuterol is highly specific, sensitive, and reliable, indicating good potential for use in the area of food safety to improve consumer protection.

Plasmonic tunable Ag-coated gold nanorod arrays as reusable SERS substrates for multiplexed antibiotics detection.

Antibiotic contaminants in aqueous media pose a serious threat to human and ecological environments. Therefore, it is necessary to develop robust strategies to detect antibiotic residues. For this purpose, a self-assembly and in situ electrochemical reduction method is utilized to tailor silver nanoparticles (AgNPs)-coated GNRs (AgNPs/GNRs) large-scale vertical arrays. These AgNPs/GNRs arrays exhibit outstanding surface-enhanced Raman scattering (SERS) activities because of abundant Raman hot-spots among the adjacent AgNPs and GNRs, but also excellent stability and reproducibility due to the close-packed arrayed nanostructure. These remarkable features validate this arrayed substrate for high-sensitivity 4-aminothiophenol analysis with a detection limit of 0.35 pM and self-cleaning via electrochemical stripping of the adsorbed analytes and AgNPs from the GNRs arrays, therefore realizing renewable SERS applications. Moreover, the distinct SERS performance of AgNPs/GNRs arrays is verified via the analysis of multiplexed antibiotics at tens of picomolar level and no apparent changes of SERS activities are observed when recyclability is explored. The result demonstrates that the proposed AgNPs/GNRs arrays provide a novel strategy for avoiding conventional, disposable SERS substrates, as well as expanding SERS applications for simultaneous sensing and stripping of environmental contaminants.

Genome-wide association study of brain amyloid deposition as measured by Pittsburgh Compound-B (PiB)-PET imaging.

Deposition of amyloid plaques in the brain is one of the two main pathological hallmarks of Alzheimer's disease (AD). Amyloid positron emission tomography (PET) is a neuroimaging tool that selectively detects in vivo amyloid deposition in the brain and is a reliable endophenotype for AD that complements cerebrospinal fluid biomarkers with regional information. We measured in vivo amyloid deposition in the brains of ~1000 subjects from three collaborative AD centers and ADNI using 11C-labeled Pittsburgh Compound-B (PiB)-PET imaging followed by meta-analysis of genome-wide association studies, first to our knowledge for PiB-PET, to identify novel genetic loci for this endophenotype. The APOE region showed the most significant association where several SNPs surpassed the genome-wide significant threshold, with APOE*4 being most significant (P-meta = 9.09E-30; ß = 0.18). Interestingly, after conditioning on APOE*4, 14 SNPs remained significant at P < 0.05 in the APOE region that were not in linkage disequilibrium with APOE*4. Outside the APOE region, the meta-analysis revealed 15 non-APOE loci with P < 1E-05 on nine chromosomes, with two most significant SNPs on chromosomes 8 (P-meta = 4.87E-07) and 3 (P-meta = 9.69E-07). Functional analyses of these SNPs indicate their potential relevance with AD pathogenesis. Top 15 non-APOE SNPs along with APOE*4 explained 25-35% of the amyloid variance in different datasets, of which 14-17% was explained by APOE*4 alone. In conclusion, we have identified novel signals in APOE and non-APOE regions that affect amyloid deposition in the brain. Our data also highlights the presence of yet to be discovered variants that may be responsible for the unexplained genetic variance of amyloid deposition.

Determination of intracellular anlotinib, osimertinib, afatinib and gefitinib accumulations in human brain microvascular endothelial cells by liquid chromatography/tandem mass spectrometry.

RATIONALE: Brain metastases are a common complication in patients with non-small-cell lung cancer (NSCLC). Anlotinib hydrochloride is a novel multi-target tyrosine kinase inhibitor (TKI) exhibiting a superior overall response rate for brain metastases from NSCLC. The penetrability of anlotinib and three generations of epidermal growth factor receptor (EGFR) TKIs (osimertinib, afatinib and gefitinib) into brain microvascular endothelial cells (HBMECs) was compared. METHODS: A sensitive quantification method for the four TKIs was developed using liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS). Anlotinib and the three EGFR TKIs were separated on an ACQUITY BEH C18 column after a direct protein precipitation, and then analyzed using electrospray ionization in positive ion mode. The linearity, accuracy, precision, limit of quantification, specificity and stability were assessed. RESULTS: The four analytes could be efficiently quantified in a single run of 3.8 min. The validation parameters of all analytes satisfy the acceptance criteria of bioanalytical method guidelines. The calibration range was 0.2-200 ng mL-1 for anlotinib and gefitinib, 1-500 ng mL-1 for osimertinib and 1-200 ng mL-1 for afatinib. The penetration of anlotinib across HBMECs was comparable with that of afatinib and gefitinib but less than that of osimertinib. CONCLUSIONS: A sensitive LC/MS/MS method to simultaneously measure anlotinib, osimertinib, afatinib and gefitinib in cell extracts was successfully validated and applied to determine their uptake inside HBMECs, which could pave the way for future research on the role of anlotinib in NSCLC brain metastases.

Impact of a novel partial defatting technology on oxidative stability and sensory properties of peanut kernels.

A novel process, 'mechanical expression preserving shape integrity', was conceived to prepare low-fat peanuts in response to health-conscious consumer demands. The main purpose of this study was to preserve the taste, aroma, and oxidative stability of the defatted product. Results generated from a central composite rotatable design showed that highest consumer sensory scores were reached at low pressures (4-6 MPa). Free fatty acid, peroxide, p-anisidine, and total oxidation values were mostly affected by water content [W] and pressure [P] with high correlation coefficients (82% < R2 < 87%). Overall, lipid oxidation and flavor fade were associated with higher defatting ratios and greater physical damage. The latter plays a major role in increasing the surface area and facilitating the access of oxygen to the remaining oil, thus rendering the defatted product more prone to oxidation. However, oxidation was reduced significantly using a Response Surface Methodology to optimize conditions ([W] 12.2 ± 0.6%d.b., [P] 6 ± 0.3 MPa and time [t] 18.2 ± 0.6 min).

Electrochemical sensing base for hazardous herbicide aclonifen using gadolinium niobate (GdNbO4) nanoparticles-actual river water and soil sample analysis.

The present work scrutinized the voltammetric analysis of hazardous herbicide aclonifen (ACF) in actual soil and river water samples utilizing the electrochemical method. The electrochemical sensing device was fabricated for the determination of ACF using gadolinium niobate (GdNbO4) nanoparticles modified glassy carbon electrode (GCE). The novel GdNbO4 sensing material was prepared via a simple co-precipitation method. Several characterization techniques (TEM, EDS, XRD, XPS, and BET) were utilized to analyze the structural features of the GdNbO4. The enhanced electrochemical behavior of GdNbO4 modified GCE towards ACF was observed compared to bare GCE. The cyclic voltammetry response revealed that the prepared sensor shows the lower negative potential with a dramatic increase in the peak current of ACF compared to bare GCE. In the differential pulse voltammetry, the limit of detection (1.15 nM) and sensitivity (23 µA µM-1 cm-2) of the ACF on the GdNbO4 modified GCE was comparatively superior to the formerly proposed ACF based sensor. This sensor reveals good selectivity, repeatability, reproducibility, and long-term stability. The reliability of the sensor exhibits satisfactory recovery results for ACF detection in river water and soil samples.

A non-mercury electrode for the voltammetric determination of butralin in foods.

A modified electrode was developed with Co-Ag bimetallic nanoparticles stabilized in poly(vinylpyrrolidone) for butralin monitoring. This is the first non-mercury electrode proposed for the quantification of butralin. The bimetallic nanoparticles were characterized by spectroscopic and microscopic techniques, which showed that they are composed of a cobalt core partially covered with silver. The modified electrode was characterized by field emission gun scanning electron microscopy, energy dispersive X-ray spectroscopy and electrochemical impedance spectroscopy. The experimental parameters (pH, supporting electrolyte, accumulation step, pulse technique) were optimized. The calibration plot for butralin obtained by square wave voltammetry was linear in the range of 0.1-1.0 µmol L-1 with limits of detection and quantification of 32 and 106 nmol L-1, respectively. Lastly, the modified electrode was effectively implemented in the quantification of butralin in honey and apple jam samples. The results were in agreement with those furnished by UV-vis spectrometry and endorsed by statistical tests.

Highly selective and antifouling electrochemical biosensors for sensitive MicroRNA assaying based on conducting polymer polyaniline functionalized with zwitterionic peptide.

Ultrasensitive and low-fouling microRNA electrochemical biosensors were successfully constructed by introducing thiol-terminated antifouling molecules (peptide sequence, polyethylene glycol, or mercapto alcohol) onto the surface of polyaniline-modified electrodes. For the three kinds of antifouling materials investigated, the newly designed and synthesized peptide exhibited superior antifouling ability to others, and it could effectively reduce the nonspecific adsorption of proteins and even prevent the fouling effect of serum. Compared with microRNA biosensors without antifouling capability, or those modified with polyethylene glycol or mercapto alcohol, the biosensor modified with the designed zwitterionic peptide showed the highest specificity for single-base mismatch, three-base mismatch, and completely complementary microRNAs. Most interestingly, the experimental results indicated that the introduction of antifouling molecules to the sensing interfaces did not significantly change the sensitivity of the biosensor. The strategy of constructing antifouling biosensors based on newly synthesized zwitterionic peptides and conducting polymers can be promisingly extended to the development of other electrochemical sensors and biosensors without encountering biofouling. Graphical abstract Ultrasensitive and low-fouling microRNA electrochemical biosensors were constructed by introducing thiol-terminated antifouling molecules (peptide sequence, polyethylene glycol, or mercapto alcohol) onto the surface of polyaniline-modified electrodes. The biosensor modified with the designed zwitterionic peptide showed the highest specificity amongst four kinds of biosensors.

Storage Stability Assessment of Red Palm Olein in Comparison to Palm Olein.

Sixty-four bottles of red palm olein and palm olein (constituted as control) samples were stored at permutations of common home setting variables which are: temperature (room temperature (24°C) or 8°C), light (kept in dark or exposure under light) and oxygen (opened or sealed caps). The effects of temperature, oxygen and light on the stability of red palm olein and palm olein were studied over 4 months of storage at simulated domestic conditions. The degree of auto- and photo-oxidations was evaluated by monitoring the following quality parameters: acidity, peroxide and p-anisidine values, fatty acids composition, carotenes and vitamin E. It is noted from the study that opened bottles of red palm olein was found to be stable for 4 months in comparison to its counterpart (palm olein) evidenced from their primary oxidative constituents (peroxides) and hydrolytic behavior (free fatty acids). Opened bottles are better off when stored at 8°C and protected from light for a longer shelf-life. Sealed bottles of palm olein showed better storage stability in the dark at 8°C; whereas sealed bottles of red palm olein was found to be stable at both temperatures studied without the influence of light. After 4 months of varying storage conditions, the fatty acid composition, vitamin E and carotenes of both oils remained unchanged. The phytonutrients in red palm olein rendered better storage stability when compared to palm olein.

Oxidative Stability of Refined Red Palm Olein under two Malaysian Storage Conditions.

Refined red palm olein (RPOo) is the first cooking oil that is a pro-Vitamin A source due to its high carotenoid concentration. The quality specifications from the manufacturers are usually applied to freshly produced oil. However, there is currently no information regarding the oxidative stability and phytonutrient content (Vitamin E and Carotene) for RPOo after prolonged storage time. The objective then is to study the effect of two local storage conditions and storage period(s) on the oxidative stability of RPOo. In this study, peroxide value (PV), p-anisidine value (AnV), induction period (IP), free fatty acid (FFA), and Vitamin E content were determined periodically for twelve months under local storage conditions (supermarket and kitchen). Carotene content, however, was determined only at initial and at the 12th month of storage time periods. It was found that there was an overall progressive but slow increase in PV and p-AnV. For PV, the storage effects were inconsistent. However, the effects were significant (p < 0.01) on the AnV throughout storage. At the end of the 12-months, for both storage conditions, the PV < 10 meq O2 g-1, the AnV < 10, the FFA < 0.2 % (palmitic acid), with a 30% drop in the total Vitamin E, and carotenoids content showed no significant drop (p < 0.01). The PV and AnV were also within Codex Alimentarius' recommended limits. Finally, the oxidative parameters showed that RPOo remains stable after year storage under the two simulated local storage conditions (the aforementioned supermarket and kitchen).

Effect of Star Fruit (Averrhoa carambola L.)By-product on Oxidative Stability of Sesame (Sesamum indicum) Oil under Accelerated Oven Storage and during Frying.

Aim of this study was to evaluate the effect of star fruit (Averrhoa carambola L.) by-products (peel and residue) on stability of sesame (Sesamum indicum) oil against oxidation. Antioxidant properties of extract of peel and residue at different time durations of extraction were determined and found that peel contains higher antioxidant potential than residue. Thus, extract of peel obtained after 24 h extraction was used to study its effectiveness on oxidative stability of sesame oil during accelerated oven storage and frying using the butylated hydroxytoluene (BHT) (200 ppm) as the reference antioxidant (positive control) and oil without added antioxidant as the negative control. The oxidative stability of the oil was determined by evaluating peroxide value, p-anisidine value, thiobarbituric acid reactive substances (TBARS) value, total oxidation (TOTOX) value, conjugated diene (CD) and conjugated triene (CT) values, and iodine value. Peel extract at different concentrations (200-1000 ppm) was tested. The oil added with peel extract exhibited higher stability against oxidation than the controls during oven storage test. Extract at 1000 ppm significantly increased the stability of sesame oil during frying as compared with controls. Thus, star fruit peel extract could be an alternative to synthetic antioxidants to suppress oxidation of edible oils.

Residue measurement of pendimethalin in tobacco by using heart-cutting two dimensional liquid chromatography coupled with tandem mass spectrometry.

A novel heart-cutting two-dimensional liquid chromatography coupled with tandem mass spectrometry method was developed for quantitative analysis of pendimethalin residue in tobacco. The strategy of reversed phase liquid chromatography coupled with another reversed-phase liquid chromatography was employed for high column efficiency and excellent compatibility of mobile phase. In the first dimensional chromatography, a cyano column with methanol/water as the eluent was applied to separate pendimethalin from thousands of interference components in tobacco. By heart-cutting technique, which effectively removed interference components, the target compound was cut to the second dimensional C18 column for further separation. The pendimethalin residue was finally determined by the tandem mass spectrometry under multiple reaction monitoring reversed-phase liquid chromatography mode. Sample pretreatment of the new method was simplified, involving only extraction and filtration. Compared with traditional methodologies, the new method showed fairly high selectivity and sensitivity with almost no matrix interference. The limit of quantitation for pendimethalin was 1.21 ng/mL, whereas the overall recoveries ranged from 95.7 to 103.3%. The new method has been successfully applied to non-stop measure of 200 real samples, without contamination of ion source. Detection results of the samples agreed well with standard method.