RESUMEN

To explore the change features of PM2.5-bound metals in a background site of North China in the past ten years, 71 and 160 samples were collected from December 2011 to January 2013 (period Ⅰ) and from September 2019 to November 2021 (period Ⅱ) in Tuoji Island National Atmospheric Monitoring Station, respectively.The concentration of metals sampled was determined using ICP-MS, and the concentrations, sources, and health risks of heavy metals were compared. The results revealed that the average concentration of PM2.5 was (54.06±39.71) µg·m-3during period Ⅱ, which was 3.53 ng·m-3 lower than that during period Ⅰ. The concentrations of Zn, Mn, As, Pb, and V in stage Ⅱ decreased by 54.53, 172.63, 0.8, 79.06, and 3.81 ng·m-3, respectively, whereas the concentrations of Cr, Cu, Cd, and Ni increased by 2.01, 5.42, 3.03, and 3.55 ng·m-3, respectively. The PMF model results indicated that the biggest contributor to PM2.5-bound metal was industrial emissions (32.32%), followed by coal combustion (27.47%), vehicle emissions (23.70%), ship emissions (9.69%), and dust sources (6.83%) during period Ⅱ. The contribution ratio of dust sources and ship emissions decreased by 20.73% and 8.83%, respectively, whereas for coal combustion and industrial emissions it increased by 2.50% and 13.52%, respectively, when compared with that during period Ⅰ. The total carcinogenic risk induced by PM2.5-bound heavy metals of period Ⅱ increased, with the highest contributions by Cr and Cd. The total non-carcinogenic risk decreased, with Mn contributing the most. Therefore, in the process of air pollution control, the control of pollution sources of heavy metals such as Cr and Mn should be reinforced.

Asunto(s)

RESUMEN

Objective:To investigate the feasibility of anthocyanins(C3G)antioxidant inhibition of autophagy to al-leviate epilepsy.Methods:Seventy-five SD rats were randomly divided into 5 groups:Control group,pentetrazole(PTZ)group,hydrogen peroxide(H2O2)intervention group,3-methyladenine(3-MA)intervention group,and C3G intervention group.The seizure grade,latency,and frequency were documented.Electroencephalography was employed to detect abnormal electrical discharges in the brain across.Patch clamp technique was utilized to measure action poten-tials in hippocampal neurons for each group.The concentration of 4-hydroxynonenoic(4-HNE)hippocampus was deter-mined using a specific kit.Ultrastructural alterations in hippocampal neurons were examined through electron microsco-pyissl staining was performed to assess neuronal damage within the hippocampus.Immunohistochemical staining and Western Blot were conducted to evaluate expression levels of 15-LOX,GPX4,and LC3 proteins within the hippocampus of rats.Results:Compared with the control group,the PTZ group was completely ignited and the modeling was success-ful.Compared with other epilepsy groups,the seizure grade of C3G group decreased,abnormal discharge decreased,latency increased,hippocampal neuron excitability decreased,nishi content increased,4-HNE content,15-LOX expression and LC3Ⅱ/LC3Ⅰ ratio decreased,but GPX4 expression increased(P＜0.05).Conclusion:The oxidative stress induced by epilepsy can induce excessive autophagy of neurons,and C3G can alleviate the occurrence and devel-opment of epilepsy by anti-oxidation and inhibition of autophagy.

RESUMEN

In this paper, two level III fugacity models are developed and applied using an environmental system containing six compartments, including air, aerosols, soil, water, suspended particulate matters (SPMs), and sediments, as a "unit world". The first model, assumes equilibrium between air and aerosols and between water and SPMs. These assumptions lead to a four-fugacity model. The second model removes these two assumptions leading to a six-fugacity model. The two models, compared using four PBDE congeners, BDE-28, -99, -153, and -209, with a steady flux of gaseous congeners entering the air, lead to the following conclusions. 1. When the octanol-air partition coefficient (KOA) is less than 1011.4, the two models produce similar results; when KOA > 1011.4, and especially when KOA > 1012.5, the model results diverge significantly. 2. Chemicals are in an imposed equilibrium in the four-fugacity model, but in a steady state and not necessary an equilibrium in the six-fugacity model, between air and aerosols. 3. The results from the six-fugacity model indicate an internally consistent system with chemicals in steady state in all six compartments, whereas the four-fugacity model presents an internally inconsistent system where chemicals are in equilibrium but not a steady state between air and aerosols. 4. Chemicals are mass balanced in air and aerosols predicted by the six-fugacity model but not by the four-fugacity model. If the mass balance in air and aerosols is achieved in the four-fugacity model, the condition of equilibrium between air and aerosols will be no longer valid.

Asunto(s)

RESUMEN

OBJECTIVE@#To investigate the effect of silencing DNA methyltransferase 1(DNMT1) to the methylation of the promoter of the tumor suppressor gene wnt-1 (WIF-1) in human chronic myeloid leukemia (CML) cells.@*METHODS@#DNMT1 siRNAi plasmid was constructed and DNMT1 siRNAi was transfected into CML K562 cells. RT-PCR and Western blot were used to detect the expression of DNMT1 gene and related protein, and methylation PCR was used to detect WIF-1 gene promoter methylation level. The trypan blue exclusion and MTT assay were used to detect the cell proliferation, flow cytometry were used to detect the cell apoptosis rate, colony formation assay was used to detect cell colony formation ability. Expression of Wnt/β- catenin and its downstream signaling pathway proteins were detected by Western blot after DNMT1 gene was silenced.@*RESULTS@#The expression level of DNMT1 mRNA and its related protein in the experimental group were significantly lower than those in the control group and negative control group (P<0.05). After 72 hours of successful transfection, the WIF-1 gene in the control group and negative control group were completely methylated, while in the experimental group, the methylation level significantly decreased. The results of MSP showed that the PCR product amplified by the unmethylated WIF-1 primer in the experimental group increased significantly,while by the methylated WIF-1 primer decreased significantly. After 48 h of transfection, the OD value, viable cell number and colony formation of the cells in experimental group were significantly lower than those in the negative control group and the control group (P<0.05). The apoptosis rate of the cells in experimental group was significantly higher than those in the negative control group and control group (P<0.05). The expression levels of β- actin, myc, cyclin D1 and TCF-1 in K562 cells in the experimental group were significantly lower than those in the negative control group and control group (P<0.05).@*CONCLUSION@#Silencing DNMT1 gene can inhibit the proliferation and promote the apoptosis of K562 cells. The mechanism may be related to reverse the hypermethylation level of the WIF-1 gene promoter, thereby inhibit the activity of the Wnt/β- catenin signaling pathway.

Asunto(s)

RESUMEN

Gas/particle (G/P) partition quotients of semi-volatile organic compounds (SVOCs) for bulk air have been widely discussed in experimental and theoretical contexts, but research on size-resolved G/P partition quotients (KPi) are scarce and limited in scope. To investigate G/P partition behavior of polybrominated diphenyl ethers (PBDEs) for size-segregated particles in the atmosphere, 396 individual size-segregated particulate samples (36 batches × 11 size-ranges), and 108 pairs of concurrent gaseous and bulk particulate samples were collected in Harbin, China. A steady-state equation based on bulk particles is derived to determine G/P partition quotients of PBDEs for size-segregated particles, which depends on the organic matter contents of size-segregated particles (fOMi). This equation can well predict KPi with knowledge of bulk partition quotient (KPS), ambient temperature, and fOMi, the results of which match well with monitoring data in Harbin and other published data collected in Shanghai and Guangzhou of China and Thessaloniki of Greece, and remedies a defect of over-estimate KPi for high-brominated PBDEs by the previous equation. In particular, the new equation contributes to obtaining the PBDEs concentrations in all atmospheric phase from partial phase, then provides a credible path to evaluate healthy exposure dose from the airborne PBDEs, by co-utilization with exposure models.

RESUMEN

Glaciers are constantly retreating because of global warming. In this study, three soil samples along the forefield of Urumqi Glacier No. 1 were collected. The effects of warming on the microbial community in the glacier forefield were investigated through a 150-day laboratory experiment. In this experiment, two temperature treatments were performed at 5℃and 15℃. The results showed that with increasing deglaciation age, the concentrations of carbon and nitrogen increased and the abundance and alpha diversity of microbial communities increased in the original samples. The 150-day laboratory experiment indicated that warming insignificantly changed the copy number of archaea and bacteria. Furthermore, it changed the microbial community composition, and the changes varied in different sampling sites. Based on the analysis of abundant OTUs changing significantly with warming, the sampling sites with shorter deglaciation age had stronger response with warming, representing an increase in the abundance of genus Thiobacillus. Furthermore, these results revealed that warming caused different effects on microbes along glacier forefield and thus, it could provide important characteristics of the microbial community with warming in alpine glacier regions.

Asunto(s)

RESUMEN

To investigate the seasonal variation of organophosphate esters (OPEs) in air particulate matter (PM) and the corresponding influence factors in indoor environment, 104 indoor PM samples were collected in a test home, Harbin, China, from March 2017 to March 2018. The Σ12OPEs concentrations ranged from 0.41 ng/m3 to 940 ng/m3. Tris(1-chloro-2-propyl) phosphate (TCIPP) was the most abundant OPE and accounted for 83.2% of the total OPEs. The Σ12OPEs concentrations in spring and summer were higher than those in autumn and winter. Outdoor total suspended particles (TSP) were the main factor that affected the concentration variation of OPEs in PM samples in the test home. Comparisons of the gas/particle (G/P) partitioning equilibrium models indicated that the Dachs-Eisenreich (D-E) model estimates were more reliable than the other models in this study. The particle fractions of OPEs with log KOA > 10.51 that predicted by all four models generally well matched the measured OPE particle fractions in the literatures. To OPEs with lower molecular weight, inhalation was the main exposure route and ingestion contributed mostly to OPEs with higher molecular weight. In addition, the estimated daily intakes (EDIs) and carcinogenic risks (CRs) posed by OPEs were all below the recommended values, indicating that the current OPE levels in the test home were within the safe thresholds.

Asunto(s)

RESUMEN

Objective:To investigate the neuroprotective effect of ibuprofen, and influence of ibuprofen in hippocampal nod-like receptor protein 3 (NLRP3) inflammatome and its related products in chronic epilepsy rats models.Methods:Thirty male SD rats were randomly divided into 3 groups: control group, pentylenetetrazol (PTZ) group and PTZ+ibuprofen group ( n=10). Rats in the PTZ group were intraperitoneally injected with PTZ (35 mg/kg) once every one d, and rats in the PTZ+ibuprofen group were intraperitoneally injected with ibuprofen (30 mg/kg) once every one d 30 min before PTZ injection; rats in the control group were intraperitoneally injected with the same amount of normal saline every one d. Injection for 15 times was performed. After the last injection, the rats were observed for 10 min, and the latency, seizure level and complete ignition of the rats in each group were recorded. Electroencephalogram (EEG) was used to detect the abnormal brain discharge in rats. Four h after last injection, HE staining and Nissl staining were used to detect the proportion of damaged hippocampal neurons in each group. Immunohistochemical staining was used to detect the absorbance values of NLRP3 inflammasome, caspase-1 and interleukin (IL)-18 positive cells in the hippocampus of rats in each group; Western blotting was used to detect the protein expressions of NLRP3 inflammatome, caspase-1 and interleukin (IL)-18 in the hippocampus of each group. Results:(1) As compared with the PTZ group, rats in the PTZ+ibuprofen group had statistically lower incidence of complete ignition, significantly longer latency and significantly lower seizure level ( P<0.05). EEG showed spikes and high amplitude epileptic wave discharge in rats of the PTZ group; EEG showed low amplitude small spiny wave and slow spiny wave in rats of the PTZ+ibuprofen group. (2) As compared with the control group, the proportion of injured hippocampal neurons significantly increased in the PTZ group and PTZ+ibuprofen group ( P<0.05); and the proportion of injured hippocampal neurons in the PTZ+ibuprofen group signficantly decreased as compared with that in the PTZ group ( P<0.05). (3) As compared with those in the control group, the absorbance values of NLRP3 inflammatome, caspase-1 and IL-18 positive cells, and the protein expressions of NLRP3 inflammatome, caspase-1 and IL-18 in the hippocampus of the PTZ group and PTZ+ibuprofen group were all significantly increased ( P<0.05); as compared with the PTZ group, the the absorbance values of NLRP3 inflammatome, caspase-1 and IL-18 positive cells, and the protein expressions of NLRP3 inflammatome, caspase-1 and IL-18 in the hippocampus in the PTZ+ibuprofen group were all significantly decreased ( P<0.05). Conclusion:Ibuprofen can inhibit the expressions of NLRP3 inflammatome, caspase-1 and IL-18, reduce the intensity of seizures, and play a neuroprotective role.

RESUMEN

Objective To analyze the infection of human parvovirus B19 among women of childbearing age in Xiangyang City, and to provide a reference for pregnant women's health care. Methods A total of 303 women of childbearing age in Xiangyang City from 2018 to 2019 were selected as the research subjects. B19 virus DNA in serum of the subjects was detected by nested PCR technology. The differences in the detection rate of B19 viral DNA among normal pregnancy, abnormal pregnancy, and infertility serum were statistically analyzed. The differences in the detection rate of B19 virus DNA among women of childbearing age at different ages were compared. Results The detection rate of B19 viral DNA in all 303 women of child-bearing age was 27.72%. The detection rate of B19 virus DNA in 26-35 year old women was higher than that in other age groups. The detection rate of B19 virus DNA in abnormal pregnancy group was significantly higher than that in normal pregnancy group (P <0.05). Conclusion The detection rate of B19 virus DNA in abnormal pregnancy and infertility group was significantly higher than that in normal pregnancy group, with the detection rate of B19 virus in 26-35 year old women of childbearing age being the highest among all age groups. It is necessary to strengthen the screening of B19 virus in pregnant women of childbearing age in this region to reduce its impact on fetal abortion.

RESUMEN

Objective To investigate the effect of ibuprofen on autophagy and astrocyte proliferation and their significances in rats with pentylenetetrazol (PTZ)-induced epilepsy. Methods Sixty male sprague-dawley rats were randomly divided into control group, PTZ group, 3-MA+PTZ group, ibuprofen+PTZ group and 3-MA+ibuprofen+PTZ group (n=12); activity of gamma-aminobutyric acid was blocked by PTZ to ignite epileptic rats in the latter 4 groups, and rats in the control group were intraperitoneally injected with normal saline once every one day; rats in the 3-MA+PTZ group and ibuprofen+PTZ group were given intraperitoneal injection of 3-MA (2.5 mg/kg) or ibuprofen (30 mg/kg) 30 min before PTZ injection;rats in the 3-MA+ibuprofen+PTZ group were given intraperitoneal injection of 3-MA (2.5 mg/kg)+ibuprofen (30 mg/kg) at the same time. The behavior and EEG features of rats were observed. Immunofluorescence staining and Western blotting were used to detect the expressions of microtubule-associated protein 1 light chain 3 (LC3) and glial fibrillary acidic protein (GFAP). Results (1) As compared with rats in the PTZ group and 3-MA+PTZ group, rats in the ibuprofen+PTZ group and 3-MA+ibuprofen+PTZ group had significantly decreased seizure grading and incidence of complete ignition, and significantly increased latency period (P<0.05). (2) The EEG waveform of the control group was normal; electroencephalogram of PTZ group and 3-MA+PTZ group showed sharp waves of high amplitude and spike waves; EEG wave peaks in the ibuprofen+PTZ group and 3-MA+ibuprofen+PTZ group decreased significantly, presenting frequent small spike waves and slow spike waves, among which ibuprofen+PTZ group showed more obvious changes. (3) The results of immunofluorescence staining and Western blotting showed that as compared with the PTZ group, 3-MA+PTZ group had statistically decreased LC3 expression and significantly increased GFAP expression (P<0.05); as compared with the PTZ group, ibuprofen+PTZ group had statistically increased LC3 expression and significantly decreased GFAP expression (P<0.05), however, 3-MA+ibuprofen+PTZ group had statistically decreased LC3 expression and significantly increased GFAP expression (P<0.05). Conclusion Ibuprofen can reduce astrocyte proliferation by promoting autophagy to affect seizures.

RESUMEN

Objective To explore the effect of quality control circle in decreasing the unqualified rate and improving quality of specimen in clinical laboratory during the pre-analytical phase.Methods The laboratory department of the First Affiliated Hospital of Kunming Medical University established quality control circle management model,since March 1 st to June 1 st 2016,following the steps of the theory and method of quality management.Used professional tools of quality control circle to solve existing problems before procedure.Then compared the disqualification rates before and after the implementation,and used chi-square test for statistical analysis.Results After activity of quality control circle,the unqualified rate of specimen in clinical laboratory declined from 0.565%to 0.220%.The difference was statistically significant (χ2=155.22,P<0.01), the goal achievement was 86.25%,the advance rate was 61.06%.And the ability of employees in using scientific means have improved.The ability of using quality control tools increased by 33.3%,the problem solving ability increased by 9.3%, the coordination and communication ability increased by 125%,the team cohesion increased by 56%and the enthusiasm increased by 20.7%. Conclusion With the application of quality control circle tools,the unqualified rate of specimen decreases and the ability of solving problems by applying of quality control circle tools.(Chin J Lab Med,2018,41:324-327)

RESUMEN

Illicit drugs and their metabolites have recently been recognized as an emerging group of contaminants due to their potential ecotoxicological impact in aquatic ecosystems. To date, information on the occurrence of these compounds in the aquatic environment of China remains limited. In this study, we collected surface water samples from 36 rivers in north China that discharge into the Bohai Sea and north Yellow Sea and measured the concentrations of amphetamine-like compounds, ketamines, cocainics, and opioids. The occurrence and spatial patterns of these substances show significant differences between the rivers and regions. Two designer drugs, methamphetamine (METH) and ketamine (KET), were the most abundant compounds detected in the entire set of samples (detection frequency of 92 and 69 %). The concentrations of METH and KET ranged from <0.1 to 42.0 ng L(-1) (mean = 4.53 ng L(-1)) and <0.05 to 4.50 ng L(-1) (mean = 0.49 ng L(-1)), respectively. The high detection frequencies of METH and KET are consistent with the fact that they are the main illicit drugs consumed in China. The high concentrations of these illicit drugs and their metabolites were found in areas that have a high population density. The riverine input of total illicit drugs into the Bohai Sea and north Yellow Sea was estimated to be in the range of 684 to 1160 kg per year.

Asunto(s)

RESUMEN

Almost 3% of newborns are diagnosed as small for gestational age(SGA)worldwide.Born SGA is one of the important causes of perinatal morbidity and mortality,and is also associated with metabolic diseases in adulthood.Low birth weight by itself is insufficient to characterize growth restriction,as it does not include information about the neonate’s body proportionality.Depending on the origin,timing and severity of in-sult,small for gestational age infants are classified into two types:proportionate or symmetric growth restriction (SGR)and disproportionate or asymmetric growth restriction(AGR).There may be differences in physical and neurological development of these two types.This study compares three classification indexes,and to find differ-ences in postnatal growth of these two types.

RESUMEN

Objective To investigate how to improve test quality by monitoring and analyzing 15 clinical laboratory quality indicators from the National Health and Family Planning Commission .Methods Data were collected from clinical laboratory department of the First Affiliated Hospital of Kunming Medical University between January 2011 and August 2015.15 quality indicators were analyzed retrospectively , including the error rate of specimen type , the coefficient variation unqualified rate of internal quality control test, the reporting rate of critical value , et al.Results The monitoring results of quality indicators basically satisfied the quality goals , except that the median of turn around time in pre-analytical phase was not established, routine internal quality control was not conducted in some laboratory tests in analytical phase and the reporting rate and reporting timely rate of critical value should be further improved in post -analytical phase .Conclusion Medical laboratory quality system can be continuously improved by means of setting up the quality goals of 15 quality indicators referring to sub-specialty and laboratory tests , as well as automated monitoring, statistics and analysis in LIS.

RESUMEN

In this study, 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed in 157 concurrently collected soil samples in 2005 over China. Higher concentration of ∑16PAHs was found in urban soil, followed by rural and background soil. The results indicated that PAHs in Chinese surface soil showed a primary distribution pattern, which was confirmed by the positive correlation with emission inventory. Based on the results of literature over the past 10 years (2004-2013) in China, the spatial distribution of PAHs in urban and rural soil was established. An obvious geographical distribution with PAH concentration was found, as higher in Eastern China and lower in Middle and Western China. Furthermore, PAH pollution in Chinese riverbank soil was summarized and showed higher levels, indicating their potential sources from polluted rivers. According to our knowledge, this is the first time to comprehensively study the PAH pollution status in Chinese surface soil on the national scale based on monitoring results.

Asunto(s)

RESUMEN

Objective To evaluate the capability for detecting of tumor cells in ascites and pleural effusion by Sysmex XN‐2000 hematology analyzer .Methods Determination of 84 samples of ascites and pleural effusion specimens with Sysmex XN‐2000 hema‐tology analyzer humoral model to analyze the study parameters highly fluorescent cells absolute value (HF‐BF # ) and percentage (HF‐BF% ) of ascites and pleural effusions screening of tumor cells ,and related data for statistical analysis .Results In 84 cases of pleural effusion and ascites samples ,cytology found 14 cases of malignant cells ,cancer cells are not found in 70 cases .14 cases of malignant cases ,HF‐BF # average of 169 /μL(0-2 001) ,HF‐BF% with an average of 29 .7% (0% -261% );70 cases of benign cases ,HF‐BF # an average of 39 /μL(0-524) ,HF‐BF% with an average of 4 .2% (0% -27 .8% ) ,both groups were statistical differences in the mean significance(P<0 .05) .ROC curve analysis with high absolute value and percentage of fluorescent cells to tumor cells detection function ,HF‐BF # area under the curve(AUC) was 0 .493 ,the area(AUC)% HF‐BF under the curve was 0 .222 .Conclusion Sysmex XN‐2000 Pattern of humoral parameters of HF‐BF # and HF‐BF% ,although the tumor cells may pro‐vide some screening information ,but ineffective ,so we believe that in our daily work can′t be over‐reliance on the instrument HF‐BF# ,HF‐BF% and other parameters should be performed on every sample smear staining ,thus improving the detection rate of ma‐lignant cells .

RESUMEN

Objective To understand the distribution of overweight and obesity in 0-5 years old children who were born small for gestational age ( SGA) in Shanghai through a cross-sectional investigation. Methods All resident children aged 0-5 years were included, covering all 18 districts in Shanghai. Health-check cards were prepared for SGA children. The check-up included weight,length/height and head circumference. Body mass index ( BMI) was used to evaluate the overweight and obesity according to the standard of World Health Organization ( WHO) . Results This study investigated 728 602 children aged 0-5 years in Shanghai,and ultimately 23 871 of them were defined as SGA,a-mong whom 9 805(41. 4%) were boys and 14 066(58. 9%) were girls. The BMI of SGA children were higher than that of appropriate for gestational age( AGA) from 4 to 18 months,while for the rest of the time,they were basically the same. There was no difference in changing tendency of BMI between SGA children and those AGA children. The distri-bution of overweight and obesity according to the standard of WHO in SGA boys among different ages was 7. 7% to 20. 7%, and 15. 7% in average;the distribution of SGA girls among different ages was 5. 9% to 18. 3%,and 12. 9% in average. The proportion of overweight at the age of 4-18 months was significantly higher than that of other ages. There was no correlation between overweight at 0-2 years old and overweight at the age of 5(P>0. 05). Conclusions Com-pared with SGA girls,overweight and obesity in SGA boys were more serious. The age of 4-18 months were the period of high incidence of overweight. There was no correlation between overweight at 0-2 years old and overweight at the age of 5.

RESUMEN

Objective: In order to evaluate the quality of Panax ginseng and its preparation, a simple and accurate HPLC method for determining the contents of 16 ginsenosides from P. ginseng was established. Methods: The chromatographic separation was achieved on a C18 column (150 mm × 4.6 mm, 5 μm) using a mobile phase made up of acetonitrie and water at a flow rate of 1.0 mL/min. The detection wavelength and column temperature were set as 203 nm and 35°C, respectively. Results: Sixteen ginsenosides (Rg1, Re, Rf, Rb1, Rg2, Rc, Rb2, Rb3, F1, Rd, F2, Rg3, protopanaxatriol, compound K, Rh2, and protopanaxadiol) were separated at baseline with good linearity (r ≥ 0.9990). The recovery rates were 95%-102% (RSD < 2%). Conclusion: The method is simple, fast, accurate, and could be applied to the quality control of P. ginseng and its preparation.

RESUMEN

As the emission source of polycyclic aromatic hydrocarbons (PAHs), domestic coal combustion has attracted increasing attention in China. According to the coal maturity, combustion form and stove type associated with domestic coal combustion, a large-size, full-flow dilution tunnel and fractional sampling system was employed to collect the emissions from five coals with various maturities, which were burned in the form of raw-coal-chunk (RCC)/honeycomb-coal-briquettes (HCB) in different residential stoves, and then the emission factors of PAHs (EF(PAHs)) were achieved. The results indicate that the EF(PAHs) of bituminous coal ranged from 1.1 mg x kg(-1) to 3.9 mg x kg(-1) for RCC and 2.5 mg x kg(-1) to 21. 1 mg x kg(-1) for HCB, and the anthracite EF(PAH8) were 0.2 mg x kg(-1) for RCC and 0.6 mg x kg(-1) for HCB, respectively. Among all the influence factors of emission factors of PAHs from domestic coal combustion, the maturity of coal played a major role, the range of variance reaching 1 to 2 orders of magnitude in coals with different maturity. Followed by the form of combustion (RCC/HCB), the EF(PAHs) of HCB was 2-6 times higher than that of RCC for the same geological maturity of the coal. The type of stove had little influence on EF(PAHs).

Asunto(s)

RESUMEN

Forty-eight surface sediment samples collected from Jiaozhou Bay, Taozi Bay and Sishili Bay were analyzed for organochlorine pesticides (OCPs) by Gas Chromatography. Results showed that average concentrations of HCHs, HCB and DDTs in marine sediments were 0.33, 0.31 and 10.33 ng x g(-1) in Jiaozhou Bay and 0.26, 0.10 and 4.56 ng x g(-1) in Taozi Bay and Sishili Bay, respectively. Contamination status of OCPs was relatively higher in Jiaozhou Bay than in other inland coastal regions, especially for the levels of DDTs; however, OCPs concentrations were relatively low in Taozi Bay and Sishili Bay. The source of HCHs could be mainly attributed to the heavy historical application in agricultural areas and late transport to coastal region through surface runoff or riverine discharge, and DDTs were primarily originated from the use of technical DDTs. Fresh input of lindane and dicofol-type DDTs were found in several sites, such as Qingdao Port. High concentrations of DDTs in Jiaozhou Bay should arouse much attention.

Asunto(s)