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2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(9): 1269-1273, 2017 Sep 10.
Article in Chinese | MEDLINE | ID: mdl-28910945

ABSTRACT

Objective: To explore the related factors of anemia during pregnancy and provide scientific evidence for the primary prevention of anemia during pregnancy. Methods: The pregnant women (≤12 pregnant weeks) who received the first pregnancy care in a local medical institution in Hunan province from June 2013 to November 2014 were included in this cohort study, and for them anemia had been excluded by physical examination. Baseline survey and follow up till childbirth were conducted for them. A queue-based nested case-control study (1 ∶ 2) was conducted (380 pregnant women with anemia detected in this study as case group, 760 pregnant women without anemia randomly selected and matched by age, habitual residence during pregnancy as control group. And t test, χ(2) test and logistic regression analysis were conducted to identify related factors of anemia during pregnancy. Results: Multivariate logistic regression analysis indicated that low family annual income level (net income) (OR=2.08, 95%CI: 1.22-3.59), low educational level (OR=2.09, 95%CI: 1.22-3.59), pre-pregnancy perm/hair dye (OR=2.23, 95%CI: 1.63-3.05), early pregnancy vomiting (OR=2.51, 95%CI: 1.56-4.03) were the risk factors for anemia during pregnancy. Intake of vitamin and trace element supplements (OR=0.69, 95%CI: 0.50-0.94), frequent meat, fish, shrimp, egg intakes (OR=0.68, 95%CI: 0.49-0.92), frequent soy milk, milk intakes (OR=0.51, 95%CI: 0.27-0.95) were the protective factors for anemia during pregnancy. Conclusion: A number of factors, such as family annual income level, education level, poisonous and harmful material contact, pregnancy reaction, nutrition, are related to the incidence of anemia during pregnancy, it is necessary to take preventive measures to reduce the incidence of anemia during pregnancy.


Subject(s)
Anemia/epidemiology , Pregnant Women , Adult , Anemia/ethnology , Case-Control Studies , China/epidemiology , Cohort Studies , Female , Humans , Incidence , Pregnancy , Prenatal Care , Risk Factors
3.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 35(10): 754-758, 2017 Oct 20.
Article in Chinese | MEDLINE | ID: mdl-29294549

ABSTRACT

Objective: To investigate the current status of job burnout in clinical nurses in a grade A tertiary hospitalin Shaoxing,China and related influencing factors. Methods: In October 2016, the Nursing Burnout Scale (NBS)was used for the investigation of 304 clinical nurses in a grade A tertiary hospital.The contents of the investigation included general data(including age,education background,working years,marital status, frequency of night shifts,professional title, and way of employment), characteristics of working environment,burnout, personality characteristics,coping strategy,and psychosomatic symptoms.SPSS 18.0 was used to conduct Pearson correlation analysis of the scores of each dimension of NBS. A multivariate regression analysis was performed with the demographic features of clinical nurses as the independent variable and the scores of each dimension of NBS as the dependent variable. Results: Among the clinical nurses in this grade A tertiary hospital, the incidence rate of severe burnout was 74%.The Pearson correlation analysis showed that burnout,pessimistic personality,negative coping,and psychosomatic symptoms were positively correlated with working environment(r=0.530,0.316,0.116,and 0.502); pessimistic personality and psychosomatic symptoms were positively correlated with burnout(r=0.618 and 0.675); psychosomatic symptoms were positively correlated withpessimistic personality(r=0.540); negative coping was negatively correlated with pessimistic personality(r=-0.145).The multivariate linear regression analysis showed that department(Department of Internal Medicine or Department of Surgery,B=-0.364 and -0.428)and frequency of night shifts(<6 times/month and 6-10 times/month,B=0.199 and 0.256)were influencing factors for the score of working environment; department(Department of Internal Medicine or Department of Surgery, B=-0.350 and -0.360)was an influencing factor for the score of burnout; 1-3 working years(B=-0.238)was an influencing factor for the score of pessimistic personality; married state,1-3 working years,and department (Department of Internal Medicine or Department of Surgery)were influencing factors for the score of psychosomatic symptoms(B=0.263,-0.301,-0.322,and -0.391). Conclusion: There is a high incidence rate of job burnout among clinical nurses in this grade A tertiary hospital,which is associated with burnout,working environment, pessimistic personality,and psychosomatic symptoms.Marital status,working years,department,and frequency of night shifts are major influencing factors for job burnout.


Subject(s)
Burnout, Professional/psychology , Job Satisfaction , Nursing Staff, Hospital/psychology , Stress, Psychological , Work Schedule Tolerance , Adaptation, Psychological , China , Humans , Nursing Staff, Hospital/statistics & numerical data , Personality , Surveys and Questionnaires , Tertiary Care Centers
4.
J Anim Physiol Anim Nutr (Berl) ; 94(5): e138-44, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20546066

ABSTRACT

The study was conducted to investigate the effect of copper-loaded chitosan nanoparticles on the composition and metabolism of the caecal microbiota in rats. Forty male Sprague-Dawley (SD) rats (average body weight of 82 ± 5 g) were randomly assigned to five groups (n = 8). The dietary treatments were: (i) basal diet, (ii) basal diet + 80 mg/kg BW CuSO(4), (iii) basal diet + 80 mg/kg BW chitosan (CS-I), (iv) basal diet + 80 mg/kg BW copper-loaded chitosan nanoparticles (CSN-I) and (v) basal diet + 160 mg/kg BW copper-loaded chitosan nanoparticles (CSN-II). The trial lasted 21 days. The results showed that compared with control, Average day gain (ADG) of group CSN-I and CSN-II increased (p < 0.05). No significant difference was found in CuSO(4) or CS-I-treated groups (p > 0.05). There were no effects of these treatments on average day feed intake (ADFI) of rats (p > 0.05). The counts of Bifidobacteria and Lactobacillus in group CSN-II were higher than those of the control group (p < 0.05), while the counts of total aerobes, total anaerobes, Salmonella, Clostridium and coliform were lower than those of the control (p < 0.05). The activity of ß-glucuronidase in group CSN-I or CSN-II was significantly depressed (p < 0.05), while the activities of α-galactosidase and ß-galactosidase were enhanced significantly (p < 0.05). The pH of the caecum digesta and the concentration of propionate and butyrate in group CSN-I and CSN-II were higher than those of the control group (p < 0.05). No significant difference was found in these parameters in CuSO(4) or CS-I-treated groups (p > 0.05). The results indicate that the microbiota and environment of caecum are beneficially changed by the administration of copper-loaded CSN.


Subject(s)
Cecum/microbiology , Chitosan/chemistry , Copper Sulfate/chemistry , Copper Sulfate/metabolism , Nanoparticles/chemistry , Animal Feed , Animals , Diet , Dietary Supplements , Male , Rats , Rats, Sprague-Dawley
5.
Anaerobe ; 16(4): 317-20, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20304080

ABSTRACT

A serodiagnostic ELISA (rL-ELISA) using recombinant truncated leukotoxin protein PL2 (aa 311-644) of Fusobacterium necrophorum as antigen was developed for detection of antibodies against F. necrophorum from cattle footrot. In rL-ELISA, the recombinant diagnostic antigen showed no cross-reaction with antisera against bovine foot and mouth disease virus, bovine rhinotracheitis virus, bovine viral diarrhea virus, bovine rotavirus type A, bovine Escherichia coli, and bovine Salmonella. The rL-ELISA could confirm the existence of antibodies against F. necrophorum at day 7 after infection. Detection of the field samples indicated relative sensitivity of rL-ELISA to nL-ELISA using the purified native leukotoxin A as antigen was 96.43%, and relative specificity of rL-ELISA to nL-ELISA was 94.26%. These data demonstrated the rL-ELISA would have a potential use for early diagnosis of cattle footrot caused by F. necrophorum.


Subject(s)
Antibodies, Bacterial/blood , Cattle Diseases/diagnosis , Enzyme-Linked Immunosorbent Assay/methods , Exotoxins , Fusobacterium Infections/veterinary , Fusobacterium necrophorum/isolation & purification , Animals , Bacterial Toxins , Cattle , Cattle Diseases/microbiology , Fusobacterium Infections/diagnosis , Fusobacterium Infections/microbiology , Fusobacterium necrophorum/immunology , Recombinant Proteins , Sensitivity and Specificity , Serologic Tests/methods , Time Factors
6.
J Anim Physiol Anim Nutr (Berl) ; 93(2): 271-6, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18492030

ABSTRACT

The effects of supplementing a barley-based diet for weaned piglets withexogenous beta-glucanase and xylanase on gastrointestinal digestiveenzyme activities were investigated. Thirty-six cross-bred weaned pigletswere randomly assigned to two groups with three pens based on sexand mass. Each group was fed on the diet based on barley with or withoutadded beta-glucanase and xylanase (0.15%) for a 4-week period. Theresults showed that enzyme supplementation improved growth performanceof piglets significantly (p < 0.05), but had no effect (p = 0.091)on average daily feed intake. The results also showed that supplementationof beta-glucanase and xylanase had no effect on pepsin activity in gastriccontents but slightly decreased (p = 0.092) the pepsin activity ingastric mucosa. Meanwhile, no effect of enzyme supplementation ontrypsin activity in duodenal contents was observed. However, the activitiesof amylase and lipase in duodenal contents were significantly(p < 0.05) decreased, whereas the activities of maltase, sucrase andgamma-glutamyl transpeptidase (gamma-GT) in jejunal and ileal mucosa wereenhanced significantly (p < 0.05). The improvement of disaccharidaseand gamma-GT activity may be attributed to the positive impacts of exogenousenzymes on digestion and absorption of the nutrients. In conclusion,the current results indicated that supplementation with enzymes in barley-based diets could improve the growth performance of piglets,decrease the activities of amylase and lipase in duodenal contents andincrease the activities of disaccharidase and gamma-GT in jejunal and ilealmucosa.


Subject(s)
Digestion/physiology , Endo-1,4-beta Xylanases/pharmacology , Gastrointestinal Tract/enzymology , Glycoside Hydrolases/pharmacology , Hordeum/chemistry , Swine/physiology , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Dietary Supplements , Enzymes/metabolism , Weaning
7.
Eur J Clin Invest ; 39(1): 37-42, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19087128

ABSTRACT

BACKGROUND: Maternal thyroid hormone deficiency is the most common disorder of thyroid function during pregnancy and can influence the outcome for mother and foetus. The purpose of this study was to investigate the prevalence of thyroid hormone deficiency during the first half of pregnancy in iodine sufficient areas of China. MATERIALS AND METHODS: Four thousand eight hundred pregnant women from 10 hospitals during the first 20 weeks of gestation were enrolled in this study. All sera obtained from pregnant women were measured for thyrotropin, free thyroxine and thyroid peroxidase antibody. Screening for thyroid hormone deficiency was performed on pregnant women using gestational age-specific reference intervals or non-pregnant population reference intervals. RESULTS: With gestational age-specific reference intervals as the criterion, the prevalence of subclinical hypothyroidism at 4, 8, 12,16 and 20 weeks of gestation was 4.59%, 6.15%, 4.68%, 4.53% and 5.96%, respectively, and the prevalence of hypothyroxinaemia was 3.69%, 1.11%, 2.92%, 1.29% and 2.29%, respectively. Different prevalence was obtained when non-pregnant population reference intervals was used as the criterion. If non-pregnant population reference intervals were used, the percentage of potentially misclassified cases of subclinical hypothyroidism were 0.18%, 2.85%, 4.1%, 3.24%, and 3.21%, respectively, and 3.45%, 0.66%, 2.34%, 1.29%, and 1.83%, respectively, in potentially misclassified cases of hypothyroxinaemia. CONCLUSIONS: The percentage of potentially misclassified cases of subclinical hypothyroidism and hypothyroxinaemia in pregnant women decreased by using the gestational age-specific reference intervals as a diagnostic criteria during the first half of pregnancy.


Subject(s)
Hypothyroidism/blood , Pregnancy Complications/blood , Thyroid Gland/physiopathology , Thyroxine/deficiency , China , Female , Humans , Pregnancy , Reference Values , Thyroid Function Tests/methods
8.
Food Addit Contam ; 23(8): 777-810, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16807205

ABSTRACT

A multi-residue method was developed for the determination of 450 pesticide residues in honey, fruit juice and wine using double-cartridge solid-phase extraction (SPE), gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method development was based on an appraisal of the characteristics of GC-MS and LC-MS-MS for 654 pesticides as well as the efficiency of extraction and purification from honey, fruit juice and wine. Samples were first diluted with water plus acetone, then extracted with portions of dichloromethane. The extracts were concentrated and cleaned up with graphitized carbon black and aminopropyl cartridges stacked in tandem. Pesticides were eluted with acetonitrile + toluene, and the eluates were concentrated. For 383 pesticides, the eluate was extracted with hexane twice and internal standard solution was added prior to GC-MS determination. For 67 pesticides, extraction was with methanol prior to LC-MS-MS determination. The limit of detection for the method was between 1.0 and 300 ng g(-1) depending on each pesticide analyte. At the three fortification levels of 2.0-3000 ng g(-1), the average recovery rates were between 59 and 123%, among which 413 pesticides (92% of the 450) had recovery rates of 70-120% and 35 pesticides (8% of the 450) had recovery rates of 59-70%. There were 437 pesticides (97% of the 450) with a relative standard deviation below 25%; there were 13 varieties (3% of the 450) between 25.0 and 30.4%.


Subject(s)
Beverages/analysis , Fruit , Honey/analysis , Pesticide Residues/analysis , Wine/analysis , Chromatography, Liquid/methods , Food Contamination/analysis , Gas Chromatography-Mass Spectrometry/methods , Reproducibility of Results , Tandem Mass Spectrometry/methods
9.
J AOAC Int ; 84(5): 1337-42, 2001.
Article in English | MEDLINE | ID: mdl-11601450

ABSTRACT

A simple and specific liquid chromatographic method was developed for determination of clopidol in chicken tissues. Samples were extracted with acetonitrile. The extracts were cleaned up on an alumina column and an anion exchange column. The clopidol was separated on a column (30 cm x 3.9 mm) of microBondapak C18 (10 microm) by using acetonitrile-water (20 + 80, v/v) as mobile phase, and determined quantitatively at 270 nm. Recoveries were 86.0-97.6%, with relative standard deviations of 2.14-9.42% at 0.010-2.0 mg/kg from 4 spiked matrixes of chicken muscle, egg, liver, and kidney. The limit of detection was 0.005 mg/kg. Compared with the modified AOAC gas chromatographic method, the present method is simple and fast to operate. Its results are accurate and reliable, making it favorable for environmental protection and meeting requirements for human safety. Thus, it is suitable for routine analysis of large quantities of samples.


Subject(s)
Chickens/metabolism , Clopidol/analysis , Coccidiostats/analysis , Drug Residues/analysis , Meat/analysis , Animals , Calibration , Chromatography, Gas , Chromatography, Ion Exchange , Chromatography, Liquid , Indicators and Reagents , Reference Standards , Solvents , Spectrophotometry, Ultraviolet
10.
J AOAC Int ; 84(5): 1343-6, 2001.
Article in English | MEDLINE | ID: mdl-11601451

ABSTRACT

A study was made of the distribution and depletion of clopidol residues at different tissue locations in chickens fed with feeds incurred with clopidol. Experiments showed that the residue levels were not identical at 5 different tissue locations in each chicken. The sequence of residue levels from high to low was livers, kidneys, upper breast, lower breast, and leg meat. The maximum residue values after suspension of the drug for 8 h were (mg/kg): livers, 4.600; kidneys, 3.619; upper breast, 1.742; lower breast, 1.641; leg meat, 1.525. The averages were taken after values for 10 chickens were determined. After suspension of the drug for 3 days, >80% residue clopidol was depleted, and the depletion was nearly completed within 7 days. The speed of depletion varied at different tissue locations in each chicken, with the sequence from fast to slow being equivalent to that of the residue levels. Analytical results of 350 samples during 7 days showed that the proposed method is specific for determination of clopidol in chickens.


Subject(s)
Chickens/metabolism , Clopidol/analysis , Clopidol/pharmacokinetics , Coccidiostats/analysis , Drug Residues/analysis , Drug Residues/pharmacokinetics , Meat/analysis , Animals , Calibration , Chromatography, Ion Exchange , Chromatography, Liquid , Coccidiostats/pharmacokinetics , Indicators and Reagents , Reference Standards , Solvents , Spectrophotometry, Ultraviolet , Tissue Distribution
11.
J AOAC Int ; 84(5): 1347-51, 2001.
Article in English | MEDLINE | ID: mdl-11601452

ABSTRACT

A summary is presented of the liquid chromatographic (LC) determination of clopidol residues in export chickens from 1992 to 1999. Over the past 8 years, we analyzed >7000 chicken samples. A total of 0.66% of samples contained clopidol residues, ranging from 0.005 to 0.79 mg/kg; however, none exceeded 3 mg/kg, the Chinese maximum residue limit. In comparison with 1992, the number of samples multiplied 70-fold, and the frequency of clopidol found in samples decreased 148-fold in 1999. The chickens inspected were exported to foreign countries; all were cleared by the buyers with no disputes. This report also introduces the critical control points of the proposed LC method as well as identification of false-positive procedures by both experience and LC/mass spectrometric confirmation. Our experiences over the past 8 years have demonstrated that the ruggedness of the proposed LC method is quite good.


Subject(s)
Chickens/metabolism , Clopidol/analysis , Coccidiostats/analysis , Drug Residues/analysis , Meat/analysis , Meat/standards , Animals , Calibration , Chromatography, Ion Exchange , Chromatography, Liquid , False Positive Reactions , Indicators and Reagents , Quality Control , Reference Standards , Solvents , Spectrophotometry, Ultraviolet , Tissue Distribution
12.
J Chromatogr A ; 882(1-2): 85-8, 2000 Jun 16.
Article in English | MEDLINE | ID: mdl-10895935

ABSTRACT

A high-performance liquid chromatographic-mass spectrometric (HPLC-MS) method has been developed for determination of clopidol residues in chicken tissues. Samples are extracted with acetonitrile. The extracts are cleaned up on an alumina column followed by an anion-exchange column. The clopidol is separated on a column (150 cmx4.6 mm) of Intertsil by using acetonitrile-water (20:80) as mobile phase. The clopidol was qualitatively identified by molecule mass and determined quantitatively by selected ion monitoring mode at 190 m/z. The recoveries with RSDs ranged from 91.6+/-10.1 to 97.3+/-5.7 at 0.010 to 10.0 mg/kg by spiking three matrices (chicken muscle, liver, and kidney). The limit of detection was 0.005 mg/kg, and the limit of quantification was 0.010 mg/kg.


Subject(s)
Chromatography, High Pressure Liquid/methods , Clopidol/analysis , Coccidiostats/analysis , Drug Residues/analysis , Mass Spectrometry/methods , Sensitivity and Specificity , Spectrophotometry, Ultraviolet
13.
J Chromatogr A ; 882(1-2): 231-8, 2000 Jun 16.
Article in English | MEDLINE | ID: mdl-10895947

ABSTRACT

This paper deals with the different GC-MS analytical conditions adopted by four laboratories in an attempt to confirm the accuracy of the GC-electron-capture detection (ECD) analytical results during the international collaborative study for the establishment of the AOAC Official Method 998. 01. What is especially noted is that two laboratories have conducted comparative analysis of the respective 12 blind samples with both methods of GC-ECD and GC-MS, and the analytical results of the two methods turn out to be basically identical. This fully demonstrates that GC-MS is not only an effective confirmation tool in the analysis of the pyrethroid residues but also of sufficient sensitivity regarding the maximum residue limit of determination prescribed by FAO/WHO. Moreover, its selectivity is better than GC-ECD.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Insecticides/chemistry , Pesticide Residues/analysis , Pyrethrins/chemistry , Insecticides/analysis , Pyrethrins/analysis
14.
J AOAC Int ; 82(1): 186-212, 1999.
Article in English | MEDLINE | ID: mdl-10028687

ABSTRACT

Fourteen laboratories from 6 countries and regions participated in an international collaborative study to evaluate a multiresidue gas chromatographic (GC) method for determining 8 synthetic pyrethroid pesticides in grains, fruits, and vegetables. The study design was based on Youden's matched-pairs principle for collaborative tests of analytical methods. Each laboratory analyzed 12 collaborative samples of wheat, oranges, and tomatoes as blind samples. Wheat samples were extracted with acetonitrile-water (2 + 1), while orange and tomato samples were extracted with acetone. Residues were partitioned into hexane, evaporated to dryness with a rotary evaporator, and then dissolved in hexane. The hexane extract was partitioned with acetonitrile and cleaned up on a 5% water-deactivated Florisil column with 6% ethyl ether in hexane as eluant. Residue concentrations were determined by GC with electron capture detection with splitless injection by comparison with single-point calibration standards. The appropriate standard concentration was determined by screening sample extracts before analysis. The multiresidue method was tested over the concentration range of 0.095-1.909 mg/kg depending on the 8 different of pesticides and agricultural products analyzed in the collaborative study. Statistical analysis of data from 13 laboratories showed weighted average recoveries for 8 pyrethroids in wheat, oranges, and tomatoes at 0.105-1.909, 0.095-1.909, and 0.105-0.954 mg/kg, respectively, ranging from 91.8 to 100.2%, from 88.1 to 100.6%, and from 88.2 to 101.5%, respectively. Reproducibility relative standard deviation values ranged from 6.46 to 17.74%, from 5.94 to 18.13%, and from 5.59 to 10.48%, respectively. Repeatability relative standard deviation values ranged from 6.34 to 10.84%, from 5.19 to 11.72%, and from 3.20 to 8.09%, respectively. The multiresidue GC method for determining synthetic pyrethroid pesticides in agricultural products has been adopted first action by AOAC INTERNATIONAL.


Subject(s)
Chromatography, Gas/methods , Food Contamination , Insecticides/analysis , Pesticide Residues/analysis , Pyrethrins/analysis , Nitriles , Permethrin
15.
J AOAC Int ; 80(1): 63-73, 1997.
Article in English | MEDLINE | ID: mdl-9011060

ABSTRACT

The stability of 8 synthetic pyrethroids in 9 crops during storage for 90 days were studied. The 8 pyrethroid insecticides were highly persistent in the 6 grains during storage. But their stabilities in 3 kinds of fruits and vegetables were different from those in the 6 grains: Most of them were degraded. Florisil purification conditions were studied with 6 batches of Florisil from 3 countries at various extents of deactivation and amounts. The best conditions of Florisil purification found in this present research agree with those found 1 year ago. The efficiencies of acetonitrile and acetone to extract the 8 pyrethroids from 6 fruit and vegetable samples were compared. The extraction efficiency of acetone was competitive with that of acetonitrile for the 6 fruit and vegetable samples. Method performance was evaluated by 6 analysts from different areas. The ruggedness tests demonstrate further that the proposed method is simple, accurate with good precision, and suitable for multiresidue analysis of pyrethroids in various agriculture products.


Subject(s)
Fungicides, Industrial/analysis , Insecticides/analysis , Pesticide Residues/analysis , Pyrethrins/analysis , Acetone/chemistry , Acetonitriles/chemistry , Edible Grain/chemistry , Fruit/chemistry , Fungicides, Industrial/metabolism , Insecticides/metabolism , Magnesium Silicates/chemistry , Nitriles , Permethrin , Pesticide Residues/metabolism , Pyrethrins/metabolism , Reference Standards , Vegetables/chemistry
16.
J AOAC Int ; 78(6): 1474-80, 1995.
Article in English | MEDLINE | ID: mdl-8664585

ABSTRACT

A simple and rapid liquid chromatographic (LC) method has been developed for simultaneous determination of 9 pyrethroid insecticides (biphenthrin, cypermethrin, fenpropathrin, fenvalerate, flucythrinate, methothrin, permethrin, py-115, and tetramethrin) in fruits and vegetables. Residues are extracted from crops with methanol and partitioned with toluene. Extracts are cleaned up by Florisil-charcoal column chromatography. LC separation is performed on a muBondapak C18 stainless steel column with acetonitrile-deionized water as mobile phase. The insecticides are detected at 206 nm with 0.03 absorbance unit full scale. Recoveries of 9 pyrethroid insecticides from 6 crops (cucumbers, tomatoes, cabbages, apples, pears, and peaches) fortified at 0.5-5.0 mg/kg were 62.7-129.2%. Detection limits were about 0.05 mg/kg, except for py-115, for which detection limit was 0.10 mg/kg.


Subject(s)
Chromatography, Liquid/methods , Food Contamination , Insecticides/analysis , Pesticide Residues/analysis , Pyrethrins/analysis , Food Analysis , Fruit/chemistry , Vegetables/chemistry
17.
J AOAC Int ; 78(6): 1481-8, 1995.
Article in English | MEDLINE | ID: mdl-8664586

ABSTRACT

We present a multiresidue method for determination of synthetic pyrethroids in fruits, vegetables, and grains. The method is a modification of AOAC Method 970.52. Residues are extracted with acetonitrile (for fruits and vegetables) or acetonitrile-water (2 + 1) (for grains) and then transferred to hexane. Coextractives are removed by acetonitrile partitioning and open-column chromatography with deactivated Florisil. The final extract is analyzed by gas chromatography with electron capture detection (GC-ECD). An HP-17 wide-bore column is used to determine the individual isomeric contents of each insecticide. The method was used to recover 8 pyrethroids (biphenthrin, fenpropathrin, cyhalothrin, permethrin, cypermethrin, fluvalinate, fenvalerate, and deltamethrin) spiked at 0.01-4.0 mg/kg in 20 crops (apple, pear, peach, banana, grape, strawberry, potato, tomato, cucumber, pepper, cabbage, carrot, celery, polished rice, wheat, green gram, buckwheat, sorghum, maize, and barley). Recoveries of the 8 pyrethroid insecticides in 6 crops ranged from 83.8 to 112.8%, with a coefficient of variation (CV) of 2.00 to 12.09% for the narrow-bore capillary GC (n = 6) and from 82.8 to 106.4%, CV = 2.93-12.19%, for the wide-bore capillary GC (n = 6). The minimum detectable levels of 0.004-0.028 mg/kg (for fruits and vegetables) or 0.01-0.08 mg/kg (for grains) for the 8 pyrethroids are easy to detect.


Subject(s)
Chromatography, Gas/methods , Food Contamination , Insecticides/analysis , Pesticide Residues/analysis , Pyrethrins/analysis , Acetonitriles , Edible Grain/chemistry , Food Analysis , Fruit/chemistry , Magnesium Silicates , Vegetables/chemistry
18.
J AOAC Int ; 78(6): 1489-96, 1995.
Article in English | MEDLINE | ID: mdl-8664587

ABSTRACT

To optimize conditions and to evaluate further a multiresidue method for pyrethroids, various extraction solvents and partitioning conditions were examined. Acetone and acetonitrile (for fruits and vegetables) and acetone-water and acetonitrile-water (for grains) were used as solvents with or without acetonitrile partitioning. Twenty crops fortified with 8 pyrethroid insecticides at low, medium, and high levels were analyzed. For limit of detection (LOD) levels, repeatability tests were completed with acetone-water as extraction solvent. Recoveries of 8 pyrethroid insecticides at LOD levels were 76.2-99.6%, with coefficients of variation (CVs) of 2.08-10.90% for narrow-bore capillary gas chromatography (GC) (n = 6) and 80.1-107.3% with CVs of 3.76-15.38% for wide-bore capillary GC (n = 6). Both acetone or acetone-water extraction with acetonitrile partitioning and acetonitrile or acetonitrile-water extraction with acetonitrile partitioning are suitable for multiresidue analysis of pyrethroid insecticides. However, acetonitrile and acetonitrile-water as extraction solvents were better than acetone and acetone-water at LOD-fortified levels. This finding was confirmed chromatographically with pear, cucumber, and barley control samples.


Subject(s)
Acetone , Food Contamination , Insecticides/analysis , Pesticide Residues/analysis , Pyrethrins/analysis , Acetonitriles , Edible Grain/chemistry , Food Analysis , Fruit/chemistry , Gas Chromatography-Mass Spectrometry/methods , Vegetables/chemistry
19.
J AOAC Int ; 77(6): 1634-8, 1994.
Article in English | MEDLINE | ID: mdl-7819770

ABSTRACT

A gas chromatographic method was developed for the simultaneous determination of 9 pyrethroid insecticides in products of animal origin. The multiresidues of the pyrethroids in different samples were extracted with acetone-petroleum ether (1 + 1), and extracts were cleaned up on a Florisil partition column and a Florisil adsorption column. Four animal tissue samples were examined at 0.05-0.25 ppm fortification levels. The average recoveries of all insecticides were 76.9-88.0%, and the coefficients of variation were < 4.6% for all insecticides except permethrin. The detection limits of the method were ca 5 ppb for all insecticides but permethrin, which had a detection limit of ca 10 ppb.


Subject(s)
Chromatography, Gas/methods , Meat/analysis , Pyrethrins/analysis , Animals , Cattle , Chickens , Magnesium Silicates , Sensitivity and Specificity , Sheep , Swine , United States , United States Food and Drug Administration
20.
J AOAC Int ; 77(3): 738-47, 1994.
Article in English | MEDLINE | ID: mdl-8012228

ABSTRACT

A simple, rapid, packed-column gas chromatographic method was developed for simultaneous determination of 10 pyrethroid insecticide residues (allethrin, biphenthrin, cyhalothrin, permethrin, cyfluthrin, flucythrinate, fenvalerate, fluvalinate, deltamethrin, and py-115) in fruits, vegetables, and grains. These multiresidues are extracted from various crops with acetone-petroleum ether and cleaned up on a Florisil column (for the fruits and vegetables) or on a Florisil-charcoal-alumina column (for the grains) prior to their determination by gas chromatography with an electron capture detector. Recoveries of 10 pyrethroid compounds from 12 different crops (maize, soybeans, wheat, sorghums, paddy, potatoes, cucumbers, cauliflowers, spinaches, apples, bananas, and oranges) fortified at levels of 0.02-5.00 ppm ranged from 58 to 130%. In a separate precision study, coefficients of variation were 5.5-14.6% at 0.1-0.5 ppm (n = 10, maize), and 4.1-12.1% at 0.010-0.050 ppm (n = 10, apples). The detection limits of the method ranged from 2.0 to 10.0 ppb on a crop basis.


Subject(s)
Chromatography, Gas/methods , Edible Grain/chemistry , Fruit/chemistry , Pesticide Residues/analysis , Pyrethrins/analysis , Vegetables/chemistry , Chromatography, Gas/statistics & numerical data , Sensitivity and Specificity
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