[Effects of applying controlled release fertilizers on N2O emission from a lateritic red soil].

Static closed chamber technique and contrast method were adopted to study the effects of three coated compound fertilizers (N:P2O5:K2O = 19:8.6:10.5, high N; 14.4:14.4:14.4, balanced NPK; and 12.5:9.6:20.2, high K) on the NO2O emission from a lateritic red soil under the condition of no crop planting, taking uncoated compound fertilizers (N:P2O5:K2O = 20:9:11, high N; 15:15:15, balanced NPK; and 13:10:21, high K) as the contrasts. Different formula of fertilizer NPK induced significant difference in the N2O emission. Under the application of uncoated compound fertilizers, the cumulative N2O emission was in the order of balanced NPK > or = high N > high K. Applying coated compound fertilizers decreased the N2O emission significantly, and the emission amount under the application of high N, balanced NPK, and high K was 34.4%, 30.5%, and 89.3% of the corresponding uncoated compound fertilizers, respectively. Comparing with the application of uncoated compound fertilizers, applying coated compound fertilizers also decreased the daily N2O flux significantly, and delayed and shortened the N2O peak, suggesting that coated fertilizers could reduce soil nitrogen loss and the global warming potential induced by N2O emission.

[Detecting the concentrations of bisphenol A (BPA) in air of workplaces with HPLC].

OBJECTIVE: To establish the method of detecting the concentrations of bisphenol A (BPA)in air of workplaces with high performance liquid chromatographic (HPLC). METHODS: According to standards of methods for determining the chemical substances in workplace air, BPA in the air was collected by glass fiber filter, then dissolved by acetonitrile and determined by high performance liquid chromatography with FLD. RESULTS: There was a linear relationship within the range of 0.01-10.0 pg /ml, and the detection limit was 0.005 pg/ml. The lowest detected concentration was 3.3x10-5 mg/m3. The relative standard deviation was 2.5-5.5%. The dissolution efficiencies were 95.0%-101.9% and the sampling efficiencies were 99.6%. The samples in glass fiber filter membrane could be stored for 7 days at room temperature. CONCLUSION: The present method could meet with the requirements of Guide for establishing occupational health standards-Part 4 Determination methods of air chemicals in workplace and be feasible for determination of BPA in workplace air.

Electroacupuncture at Qiuxu (GB 40) for treatment of migraine--a clinical multicentral random controlled study.

OBJECTIVE: To observe the therapeutic effects of electroacupuncture (EA) at Qiuxu (GB 40) for treatment of migraine so as to provide clinical evidence for compilation of the Acupoints' Dictionary of the People's Republic of China. METHODS: 275 migraine patients admitted in 3 hospitals were randomly divided into a treatment group treated by EA at Qiuxu (GB 40), and a control group treated by EA at Tianshu (ST 25). The indexes of the migraine symptoms and the 5-HT level were observed in both the groups before and after treatment. RESULTS: There was a significant difference in VAS score between the two groups of the 3 clinical centers (P<0.01). The therapeutic effects of a 4-week treatment were much better in the treatment group than that of the control group. The 3-month follow-up survey showed that the long-term effects were in favor of the treatment group of the first and third clinical centers, though no significant difference was found in the treatment group of the second clinical center as compared with the control group. The results from the 6-month follow-up survey showed better effects in the treatment group of all the 3 clinical centers. CONCLUSION: EA at Qiuxu (GB 40) may show effect for migraine.

[Levels of environmental endocrine disruptors in umbilical cord blood and maternal blood of low-birth-weight infants].

OBJECTIVE: To monitor the biological levels of environmental endocrine disruptors (EDs, phthalates and surfactants) in the umbilical cord blood and maternal blood of low-birth-weight infants. METHODS: All 30 umbilical cord blood samples and 21 maternal blood samples were collected from low-birth-weight infants. The concentration of four kinds of phthalates (di-2-ethylhexyl phthalate, DEHP; mono-2-ethylhexyl phthalate, MEHP; di-ethyl phthalate, DEP; di-n-butyl phthalate, DBP) and two kinds of surfactants (4-nonylphenol, 4-NP; octylphenol, OP) in these blood samples were measured by using reversed-phase high performance liquid chromatography. RESULTS: The mean birth weight and birth length of low-birth-weight infants were (2158.48 +/- 125.06) g and (45.36 +/- 2.52) cm, respectively. The concentrations of DEP, MEHP, DBP, DEHP, 4-NP and OP were 18.90, 11.87, 7.67, 8.84, 1.51 and 2. 86 mg/L in maternal blood, and the detective rates were 86.7%, 63.3%, 60.0%, 63.3%, 56.7% and 66.7%, respectively. In umbilical cord blood, the concentrations of those EDs were 11.92, 9.94, 5.71, 5.20, 1.12 and 1.19 mg/L; the detective rates were 86.7%, 63.3%, 60.0%, 63.3%, 56.7% and 66.7%. No matter in maternal blood or in umbilical cord blood, the contents and detective rates of phthalates were higher than the surfactants. The concentration of MEHP was higher than its primer, DEHP. The contents of the target EDs in umbilical cord blood were less than those in the matched maternal blood. The percentages were 47.82% -84.05%. CONCLUSION: People could be exposed to EDs from embryo period. And this should be paid attention by the related departments.

[Study on the therapeutic effect of electroacupuncture on migraine and influencing factors].

OBJECTIVE: To compare therapeutic effects of electrical acupuncture (EA) at Qiuxu (GB 40) and Tianshu (ST 25), and to probe the factors of influencing the therapeutic effect. METHODS: Two hundred and seventy-five cases were randomly divided into the test group of 138 cases treated with EA at Qiuxu (GB 40) and the control group of 137 cases treated with EA at Tianshu (ST 25). Their therapeutic effects were observed and the factors influencing the therapeutic effect were analyzed. RESULTS: The transient effective rate was 70.3% in the test group and 58.4% in the control group with a significant difference between the two groups (P<0.05), and there were very significant differences between the two groups in the therapeutic effects at treatment of 4 weeks, and following-up 3 and 6 months later (P<0.001), the transient analgesic effect of EA at Qiuxu (GB 40) being better. EA had better transient effect on migraine for the mental workers, or the patient with high pain score at treatment, or more frequent attack. The long-term analgesic effect of EA at Qiuxu (GB 40) was better than Tianshu (ST 25). CONCLUSION: The analgesic effect of EA at Qiuxu (GB 40) is better than Tianshu (ST 25) and the profession and conditions of the patient are the factors influencing the therapeutic effect.

[Effect of dimethoate on serum monoamines neurotransmitters in rats].

OBJECTIVE: To study the effect of dimethoate on the monoamine Neurotransmitters, including norepinephrine (NE), epinephrine (E), serotonin (5-HT), dopamine (DA) and its metabolite (3, 4-hydroxyphenylacetic acid, DOPAC) in the serum of rats and furthermore to explore the non-cholinergic mechanism of organophosphate induced toxicity. METHODS: Groups of rats were treated with saline and 38.9, 83.7 and 180 mg/kg dimethoate respectively and were decapitated at the different time course from 0.5 to 24 hours after the administration. The monoamines neurotransmitters were determined by the reverse-phase high-performance liquid chromatography with the electrochemical detection. RESULTS: The serum concentrations of DA (8.42% - 248.42% of the control), DOPAC (17.22% - 68.21% of the control) increased, according with the DM dosage and the exposure time, while the levels of NE (9.65% - 38.26% of the control) and E (11.00% - 32.62% of the control) contents decreased at the same time. CONCLUSION: These findings indicate that dimethoate induced toxic effects can alter the monoamine levels at the different dosage and the time exposure in the serum of rats. It suggests that some non-cholinergic mechanisms may be involved in the dimethoate intoxication.

Phthalate exposure and human semen quality in Shanghai: a cross-sectional study.

OBJECTIVE: To monitor the level of phthalates in human semen samples and to analyze the relationship between phthalate levels and semen parameters. METHODS: Concentrations of three kinds of commonly used phthalates (di-ethyl phthalate, DEP; di-n-butyl phthalate, DBP; di-2-ethylhexyl phthalate, DEHP) were measured using reversed-phase HPLC. Semen parameters were measured by computer aided sperm analysis (CASA). RESULTS: The three phthalates were detected in most of the biological samples, with median levels of 0.30 mg/L (0.08-1.32 mg/L) in semen specimens. There was a significant positive association between liquefied time of semen and phthalate concentrations of semen. The correlation coefficient was 0.456 for DEP, 0.475 for DBP, and 0.457 for DEHP, respectively. There was no significant difference between phthalate concentrations of semen and sperm density or livability, though the correlation coefficients were negative. CONCLUSION: These results suggest that people who reside in Shanghai are exposed to phthalates, especially to DBP and DEHP. Although the level of phthalates is relatively mild, an association of phthalate levels and reduced quality of human semen has been shown in the present study.

[Elevation of some serum liver enzymes in coke oven workers and the possible relationship with exposure to polycyclic aromatic hydrocarbons].

OBJECTIVE: To explore the dose-response relationship between exposure to polycyclic aromatic hydrocarbons (PAHs) and the elevation of some serum liver enzymes in coke oven workers. METHODS: Cumulative exposure level of total 16 PAHs (CEL-PAHs) and urinary 1-hydroxypyrene (1-OHP) concentrations were assessed, liver enzymes including alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT) and alkaline phosphatase (ALP) were determined between coke oven workers and non-occupational PAHs exposed workers with negative hepatitis B surface antigens (HBsAg). RESULTS: The exposure levels of PAHs in coke oven workers were significantly higher than in control group (P < 0.05). Compared with referents, significant elevation of serum ALT can be found in the group of CEL-PAHs minor than 50 microg/(m3 x a) or in the group of urinary 1-OHP concentrations minor than 2.3 micromol/mol creatinine, as well as significant elevation of serum AST in the group of CEL-PAHs minor than 50 microg/(m3 x a) (P < 0.05). Compared with control group, the elevation of enzyme level in all four serum liver and the higher prevalence of abnormal serum ALT, AST and GGT level can be found both in the group of CEL-PAHs higher than 200 microg/(m3 x a) and in the group of urinary 1-OHP concentrations higher than 10.0 micromol/mol creatinine (P < 0.05), especially for the elevation of enzyme level in serum GGT (10-fold increase in CEL-PAHs resulted in 1.24-fold increase in serum GGT, as well as 10-fold increase in urinary 1-OHP resulted in 1.19-fold increase) and higher prevalence in serum GGT (logistic analysis: adjusted Odds Ratio: 6.2 - 7.2, P < 0.05). CONCLUSION: The elevation of some liver enzymes in coke oven workers may be related to their high exposure level of PAHs.

[Determination of ergosterol amount in house dust of different indoor environment in Shanghai City by HPLC].

OBJECTIVE: A high performance liquid chromatographic (HPLC) method was developed for the determination of the amount of ergosterol in house dust, and was examined the feasibility on determination of ergosterol in house dust. According to the established method, different house dusts derived from different functional indoor air was sampled and determined. We expected to regard ergosterol as an indicator of fungal biomass. METHODS: We picked up dust samples from nine typical functional indoor area to represent different room temperature, ventilation, air conditioning, human activities, pet-feeding, et al, during Dec 2004 to Jan 2005. The house dust was sampled with a dust collector, and filtrated with a filter. Fine house dusts were extracted by ultrasonic blending, filtration, refluxing, saponification and evaporation. High liquid chromatography was carried out and combined with gas chromatography (GC)-mass spectrometry (MS) to analyze the molecular structure. RESULTS: A linearity association was observed in the range of 0.02 to 0.8 g/L ergosterol. The detection concentration was 0.0005 g/L. The intra-and inter-day relative standard deviations (RSD) were in the range of 10.2% - 11.7% and 4.54% - 7.34%, respectively. The absolute recoveries ranged between 77.1% and 80.1%. Survey results showed the amount of ergosterol differed greatly from the different sampling spots. The amount of ergosterol had a positive correlation with room temperature and people denseness, while had a negative correlation with natural ventilation, briefly. The highest amount was 66.08 microg/g (house dust). CONCLUSION: The method is sensitive, accurate and feasible. It can examine different ergosterol content in environmental matrix. Followed by GC-MS, the reliability of the results can be further checked. The sampling data show there are different degrees of fungal contamination in typical indoor air of Shanghai City.

[Determination of four kinds of environmental endocrine disruptors in blood serum of precocious puberty patients by high performance liquid chromatography].

OBJECTIVE: This study was directed to the development of a simple and highly sensitive method for determination of four kinds of environmental endocrine discrupters (EEDs) in the serum of precocious puberty patients using reversed-phase HPLC. METHODS: The serum samples were extracted by n-hexane. The operating conditions were such as C18 column (4.6 mm x 250 mm 5 microm), methanol: H2O: trifuorocuetic acid (1000 : 50 : 1) as mobile phase at a flow rate of 1 ml/min. Using ultraviolet detector, DEHP and MEHP was determined with wavelength at 228 nm, p, p'-DDE was determined with wavelength at 238 nm. Fluorescence detector with the excitation and emission wavelength at 275 nm and 312 nm respectively were used to determine 4-NP. RESULTS: There was a good linear relationship between the concentrations of the analytes in serum and their peak areas in the range of for DEHP, for MEHP, for p, p'-DDE and for 4-NP. The detection limit of the method was 1 ng/ml for each of the analytes. Recoveries of serum samples were 96.84% - 103.44% for DEHP, 87.69% - 104.92% for MEHP, 87.6% - 109.89% for p, p'-DDE, 98.57% - 105.1% for 4-NP. CONCLUSION: The method is suitable for the determination of the four kinds of EEDs in serum. It is easy to dispose the samples. The volume of samples is decreased and the effect of detection is increased. The method is quicker and easier and could be widely used to determine these compounds. It is helpful for the clinical study of precocious puberty.

[Determination of time-weighted average concentration for vinyl chloride in the air of workplace].

OBJECTIVE: To establish a gas chromatographic method with carbon disulfide desorption for time-weighted average (TWA) concentration of vinyl chloride in the air of workplace. METHODS: Vinyl chloride in the air was sampled individually with activated charcoal tube. Vinyl chloride was desorbed by carbon disulfide for 30 minutes and analyzed by GC (FID). Time was used for qualitative analysis and peak area was for quantitative analysis. RESULTS: Linearity range was 0.0264-1.6896 mmol/L and the coefficient of correlation was 0.9999. Limit of detection: 1.2 ng (injection of 1microl). Relative standard deviation that expressed precision ranged from 3.8% to 6.7% for different concentrations. And average desorption efficiency of carbon disulfide was 90.77%. CONCLUSION: These indicators were corresponding to the Chinese guideline of the method for determination of toxic substances in workplace air and confirmed to be suitable for determining TWA concentration of vinyl chloride in workplace.

[Study on monoamine neurotransmitters in rat serum and brain tissue by high performance liquid chromatography with electrochemical detection].

OBJECTIVE: A rapid, reliable and simple method detecting monoamine neurotransmitters in rat serum and brain tissue by high performance liquid chromatography with electrochemical detector was developed. METHODS: An ODS column was selected as separation column at room temperature,and the mobile phase (pH4.50) consisted of 0.02 mol/L trisodium citrate and 0.05 mol/L disodium phosphate, containing 15% methanol (volume ratio)in distilled water. The mobile phase was pumped at a flow rate of 1.0 ml/min and the oxidation potential was set at +0.065 mV. Dihydroxybenzylamine was used as the internal standard for quantification. Four compounds, epinephrine (E), dopamine (DA) and 5-hydroxytryptamine(5-HT) in the brain tissue ((whole cerebral cortex, hippocampus, striatum, midbrain, cerebellum) and serum were simultaneously separated and determined under the above conditions. RESULTS: RSD of the retention times and peak areas of standard sample was in the range 0.29%-0.67% and 0.09%-0.36%. The recoveries of all analytes were over 85%. The detection limits of 0.083 ng/ml for NE, 0.51 ng/ml for E, 0.046 ng/ml for DA and 0.078ng/ml for 5-HT were achieved with standard solutions. The linearity is over the range 1.0-100 ng/ml for NE, 5.0-80 ng/ml for E,1.0-80 ng/ ml for DA and 1.0-60 ng/ml for 5-HT. CONCLUSION: The assay had been applied successfully to measure simultaneously cortex and serum concentrations of these four monoamines in rats.

[Study on the level of environmental endocrine disruptors in serum of precocious puberty patients].

OBJECTIVE: To investigate the role of environmental endocrine disruptors (EEDs) in causing the precocious puberty. METHODS: The blood samples were collected from 79 cases of precocious puberty patients and 42 cases of normal children. The concentrations of 4-nonylphenol (4-NP), 1, 1-dichloro-2, 2, bis (p-chlorophenyl) ethylene (p, p'-DDE) and di-2-ethylhexyl phthalate (DEHP) in blood serum samples were measured by using reversed-phase high performance liquid chromatography (HPLC). The volume of uterus and ovary, the bone density, and the content of estradiol (E(2)) in serum were determined at the same time. The contents of EEDs in blood serums of precocious puberty and the indices of the target organs were analyzed by using of correlation and regression. RESULTS: In normal control group, p, p'-DDE was detected in all the blood samples (14.93 - 40.39 ng/ml), but 4-NP and DEHP were detected in some samples (ND -6.77 ng/ml, ND -17.61 ng/ml). The levels of 4-NP, p, p'-DDE and DEHP in blood serum in precocious puberty group were notably increased than that in control group (P < 0.01). In precocious puberty group, there was a positive correlations between the 4-NP in volume of uterus and the volume of ovary and the density of bone (r = 0.394, 0.286, 0.237, P < 0.01); p, p'-DDE and volume of uterus also showed a the positive correlation (r = 0.306, P < 0.01). The influencing extent of 4-NP was 1.3 times to that of the p, p'-DDE. CONCLUSION: The normal children and the children with precocious puberty should be all contaminated by EEDs, and the later be exposured to more EEDs. There might exist a close relationship between EEDs and the precocious puberty, and EEDs should be an important factor in causing the disease. Different kinds of EEDs might have different influencing extents to the target organs.

[Comparison on urinary 1-hydroxypyrene concentrations between coke oven workers and non-occupational exposed individuals].

OBJECTIVE: To compare the urinary 1-hydroxypyrene (1-OHP) concentrations between coke oven workers and non-occupational exposed individuals and to investigate the possible impact factors. METHODS: Spot end-of-shift urine samples were collected in 265 coke oven workers and spot morning urine samples in 226 non-occupational exposed individuals. External exposure levels and possible confounding factors were assessed by environmental polycyclic aromatic hydrocarbons (PAH) monitoring and uniform questionnaire, and the urinary 1-OHP concentrations determined by high performance liquid chromatography (HPLC), were used to compare the different urinary 1-OHP levels between different research populations and to explore the effects of several factors such as external exposure levels, smoking habits, alcohol consumptions, age and body mass index (BMI). RESULTS: The urinary 1-OHP concentrations in coke oven workers were significantly higher than those in non-occupational exposed individuals (13.49, 6.56, 1.38 and 0.35 micromol/mol creatinine for topside workers, side-oven workers, bottom side workers and references, respectively, P < 0.001; the same trends for the percentage of the level over 2.3 micromol/mol creatinine: 94.81%, 84.73%, 35.09% and 0.88%, P < 0.001). The control individuals who smoked over 20 cigarettes per day possessed higher urinary 1-OHP concentrations than the non-smokers (adjusted geometric mean: 0.47 and 0.31 micromol/mol creatinine, respectively, P < 0.05). Alcohol drinking references possessed lower urinary 1-OHP levels than the non-drinkers (adjusted geometric mean: 0.33 and 0.47 micromol/mol creatinine, respectively, P < 0.05). CONCLUSION: Coke oven workers should be exposed to a high level of urinary 1-OHP, especially for topside workers and side-oven workers. Background urinary 1-OHP levels in non-occupational exposed individuals should be related to smoking habits and alcohol consumptions.

[Survey on the contamination of microcystin-LR in water supply of Shanghai city].

OBJECTIVE: To study the pollution level of microcystin-LR in water supply of Shanghai city and the removal efficacy for microcystin-LR through routine water treatment technique. METHODS: High performance liquid chromatogram (HPLC) was applied to determine the concentration of microcystin-LR in source water, water samples after various water treatment procedures and tap water. RESULTS: The concentration of microcystin-LR varied with sampling seasons and sites and reached peak during summer and fall. The maximum of microcystin-LR was 2.38 microg/L in source water. Coagulation plus chlorine disinfection were found to be effective for the removal of microcystin-LR, while the remove rate through filtration was not significant. And it could also be detected in tap water as high as 1.27 microg/L. CONCLUSION: The source waters of Shanghai city were polluted by cyanobacteria toxins represented by microcystin-LR. The source water in suburb was more polluted. Routine water treatment techniques can not remove the toxins effectively.