Polycyclic aromatic hydrocarbons degradation by marine-derived basidiomycetes: optimization of the degradation process

ABSTRACT Pyrene and benzo[a]pyrene (BaP) are high molecular weight polycyclic aromatic hydrocarbons (PAHs) recalcitrant to microbial attack. Although studies related to the microbial degradation of PAHs have been carried out in the last decades, little is known about degradation of these environmental pollutants by fungi from marine origin. Therefore, this study aimed to select one PAHs degrader among three marine-derived basidiomycete fungi and to study its pyrene detoxification/degradation. Marasmiellus sp. CBMAI 1062 showed higher levels of pyrene and BaP degradation and was subjected to studies related to pyrene degradation optimization using experimental design, acute toxicity, organic carbon removal (TOC), and metabolite evaluation. The experimental design resulted in an efficient pyrene degradation, reducing the experiment time while the PAH concentration applied in the assays was increased. The selected fungus was able to degrade almost 100% of pyrene (0.08 mg mL-1) after 48 h of incubation under saline condition, without generating toxic compounds and with a TOC reduction of 17%. Intermediate metabolites of pyrene degradation were identified, suggesting that the fungus degraded the compound via the cytochrome P450 system and epoxide hydrolases. These results highlight the relevance of marine-derived fungi in the field of PAH bioremediation, adding value to the blue biotechnology.

Degradation of polynuclear aromatic hydrocarbons by two strains of Pseudomonas

ABSTRACT The goal of this investigation was to isolate competent polynuclear aromatic hydrocarbons degraders that can utilize polynuclear aromatic hydrocarbons of former industrial sites at McDoel Switchyard in Bloomington, Indiana. Using conventional enrichment method based on soil slurry, we isolated, screened and purified two bacterial species strains PB1 and PB2. Applying the ribotyping technique using the 16S rRNA gene analysis, the strains were assigned to the genus Pseudomonas (Pseudomonas plecoglossicida strain PB1 and Pseudomonas sp. PB2). Both isolates showed promising metabolic capacity on pyrene sprayed MS agar plates during the preliminary investigations. Using time course studies in the liquid cultures at calculated concentrations 123, 64, 97 and 94 ppm for naphthalene, chrysene, fluroanthene and pyrene, P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 showed partial utilization of the polynuclear aromatic hydrocarbons. Naphthalene was degraded between 26% and 40%, chrysene 14% and 16%, fluroanthene 5% and 7%; pyrene 8% and 13% by P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 respectively. Based on their growth profile, we developed a model R2 = 1 to predict the degradation rate of slow polynuclear aromatic hydrocarbon-degraders where all the necessary parameters are constant. From this investigation, we confirm that the former industrial site soil microbial communities may be explored for the biorestoration of the industrial site.

Morphological changes and growth of filamentous fungi in the presence of high concentrations of PAHs

In this study, we evaluated the effect of low and high molecular weight polycyclic aromatic hydrocarbons (PAHs), i.e., Phenanthrene, Pyrene and Benzo[a]pyrene, on the radial growth and morphology of the PAH-degrading fungal strains Aspergillus nomius H7 and Trichoderma asperellum H15. The presence of PAHs in solid medium produced significant detrimental effects on the radial growth of A. nomius H7 at 4,000 and 6,000 mg L⁻¹ and changes in mycelium pigmentation, abundance and sporulation ability at 1,000–6,000 mg L⁻¹. In contrast, the radial growth of T. asperellum H15 was not affected at any of the doses tested, although sporulation was observed only up to 4,000 mg L⁻¹ and as with the H7 strain, some visible changes in sporulation patterns and mycelium pigmentation were observed. Our results suggest that fungal strains exposed to high doses of PAHs significantly vary in their growth rates and sporulation characteristics in response to the physiological and defense mechanisms that affect both pigment production and conidiation processes. This finding is relevant for obtaining a better understanding of fungal adaptation in PAH-polluted environments and for developing and implementing adequate strategies for the remediation of contaminated soils.

A study of the status of exposure to polycyclic aromatic hydrocarbons (PAHs) in relation to its metabolites among workers in a Korean chemical factory / Um estudo sobre o estado de exposição a hidrocarbonetos aromáticos policíclicos (HAPs), em relação aos seus metabolitos, entre os trabalhadores em fábricas de produtos químicos coreana

The study was conducted to evaluate the status of worker exposure to polycyclic aromatic hydrocarbons (PAHs) through the measurement of urinary metabolites such as 1-hydroxypyrene (OHP) and 2-naphthol. A survey using a questionnaire involving 326 workers with measurement of urinary metabolites of 1-OHP and 2-naphthol was conducted. The differences in urinary 1-OHP and 2-naphthol concentrations, and changes in work, smoking habits and lifestyle were analyzed. The number of male subjects was 314 (96.3%), the largest age group was the fifth decade (170 cases, 52.1%). The urinary 1-OHP and 2-naphthol concentrations were significantly higher in the production workers. The urinary 1-OHP and 2-naphthol concentrations were significantly higher in smokers. In a multiple regression model, log (1-OHP) increased in smokers and production workers, while log (2-naphthol) only increased in smokers. Our results suggest that workers in this factory were exposed to PAHs from non-occupational as well as occupational sources. The occupational exposure to PAHs can be reduced through the improvement of the process, but the exposure due to smoking can be prevented only by giving up smoking.

O presente estudo foi realizado para avaliar o estado de exposição a hidrocarbonetos aromáticos policíclicos (HAPs) em trabalhadores, por medição de metabólitos urinários, tais como 1-hidroxipireno (OHP) e 2-naftol. Foi realizada uma pesquisa por questionário envolvendo 326 trabalhadores e a mensuração dos metabólitos urinários de 1-OHP e 2-naftol. Foram analisadas as diferenças na urinária 1-OHP e as concentrações de 2-naftol e mudanças pelo trabalho, hábito de fumar e estilo de vida. O número de indivíduos do sexo masculino foi de 314 (96,3%), a maior faixa etária foi a quinta década (170 casos, 52,1 %). Com relação aos metabólitos urinários 1 -OHP e 2-naftol, as concentrações foram significativamente maiores nos trabalhadores produtivos. As concentrações dos metabólitos urinários 1-OHP e 2-naftol foram significativamente maiores nos fumantes. Em um modelo de regressão múltipla, log (1-OHP) aumentou em fumantes e em trabalhadores produtivos, enquanto que log (2-naftol) aumentou apenas em fumantes. Nossos resultados sugerem que os trabalhadores desta fábrica foram expostos tanto a HAPs de fontes não ocupacionais como ocupacionais. A exposição ocupacional a HAPs pode ser diminuída através da melhoria do processo, mas a exposição devido ao fumo só pode ser impedida interrompendo esse hábito.

Polycyclic aromatic hydrocarbons monohydroxy metabolites level in urine of general population in eight provinces of China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To assess the levels of polycyclic aromatic hydrocarbons monohydroxy metabolites in urine of general population in China among 8 provinces, provide the baseline of the metabolites in the general population.</p><p><b>METHODS</b>From 2009 to 2010, 18 120 subjects of general population aged 6-60 years old were recruited from 24 areas among 8 provinces in east, west and central areas of China mainland by cluster random sampling. The information of the living environment and health condition were collected by questionnaire and spot urine samples were collected, 4 680 urine samples were analysed by high performance liquid chromatography with tandem mass spectrometry, and monohydroxy metabolites distribution in urine among groups of gender and ages were analysed.</p><p><b>RESULTS</b>Geometric means (GM) of 2-naphthol, 1-naphthol, 3-phenanthrol and 1-hydroxypyrene concentration in urine (95%CI) were 1.85 (1.75-1.95), 1.55 (1.50-1.61), 0.57 (0.54-0.59) and 0.82 (0.78-0.85) µg/L, respectively;and median are 2.44, <0.50, 0.72 and 0.90 µg/L, respectively. The concentration between male and female were significantly different (P < 0.01), and the concentration among the groups of population were significantly different (P < 0.01), the GM of 2-naphthol among the groups of population aged 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were 1.60, 1.56, 1.69, 2.23, 1.91 and 1.86 µg/L (χ(2) = 17.90, P < 0.01), the GM of 1-naphthol in the groups were 1.30, 1.16, 1.53, 1.68, 1.80 and 1.52 µg/L (χ(2) = 76.22, P < 0.01), the GM of 3-phenanthrol in the groups were 0.78, 0.76, 0.55, 0.42, 0.50 and 0.99 µg/L (χ(2) = 66.48, P < 0.01), the GM of 1-hydroxypyrene in the groups were 0.77,0.64, 1.00, 0.84, 0.84 and 0.57 µg/L (χ(2) = 51.48, P < 0.01), respectively.</p><p><b>CONCLUSION</b>The distribution of monohydroxy metabolites levels in urine of general population were different, it provided a basic data for the further study of polycyclic aromatic hydrocarbons biomonitoring in the population.</p>

Characterization of pyrene utilizing Bacillus spp. from crude oil contaminated soil

Pyrene, a high molecular weight polycyclic aromatic hydrocarbon (PAH), is a priority pollutant present in soil contaminated with crude oil, coal-tar and complex PAHs. Bacterial consortium CON-3 developed from crude oil contaminated soil of Patiala, Punjab (India) cometabolized 50 µg ml-1 pyrene in the presence of glucose (0.5 %; w/v) at 30 °C, as determined by reverse-phase high performance liquid chromatography (HPLC). Bacillus sp. PK-12, Bacillus sp. PK-13 and Bacillus sp. PK-14 from CON-3, identified by 16S rRNA gene sequence analysis, were able to cometabolize 64 %, 55 % and 53 % of pyrene in 35 days, respectively. With the increase in glucose concentration to 1.0 % (w/v) in growth medium isolates PK-12, PK-13 and PK-14 showed 19 - 46 % uptake of 50 µg ml-1 pyrene in 4 days, respectively. Uptake of pyrene was correlated with growth and biosurfactant activity, which is suggestive of the potential role of members of Bacillus genera in pyrene mobilization and its uptake.

Effects of smoking on the concentrations of urinary 10 metabolites of polycyclic aromatic hydrocarbons in coke oven workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the effects of smoking on urinary 10 metabolites of polycyclic aromatic hydrocarbons (PAHs) in the coke oven workers.</p><p><b>METHODS</b>Occupational health examination was performed on 1401 coke oven workers in one coking plant, their urine were collected respectively. The concentrations of the ten monohydroxy polycyclic aromatic hydrocarbons in urine were detected by gas chromatography/mass spectrometry. The 1401 workers were divided into four groups, namely control, adjunct workplaces, bottom and side, top group according to their workplaces and the different concentrations of PAHs in the environment. The concentrations of the ten monohydroxy polycyclic aromatic hydrocarbons between smokers and nonsmokers in each workplace group were compared using analysis of covariance, respectively.</p><p><b>RESULTS</b>The levels of concentrations of the sixteen polycyclic aromatic hydrocarbons we detected at control were significantly higher than those at other areas (P < 0.05). Comparing the ten monohydroxy polycyclic aromatic hydrocarbons levels between smokers and nonsmokers, the levels of 1-hydroxynaphthalene and 2-hydroxynaphthalene among smokers were higher than nonsmokers with statistically significance in control, adjunct workplaces, bottom and side and top groups (P < 0.05). However, the levels of 1-hydroxypyrene had no statistically significant differences between the four areas.</p><p><b>CONCLUSION</b>Urinary 1-hydroxynaphthalene and 2-hydroxynaphthalene may be used as biomarkers for the impact of smoking on monohydroxy polycyclic aromatic hydrocarbons in the coke oven workers.</p>

The dose response decrease of lung function associated with the urinary polycyclic aromatic hydrocarbons metabolites in coke oven workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To analyze the relationship between metabolites of polycyclic aromatic hydrocarbons (PAHs) and lung function in coke oven workers, and to provide scientific basis for further exploring the potential mechanism and developing the preventing strategies of the workers' early lung damage.</p><p><b>METHODS</b>We measured carbon monoxide, sulfur dioxide, benzene soluble matter, particulate matters, and PAHs at different workplaces of a coke oven plant. Detailed information on demography and occupational health condition of 912 workers were collected. We divided these workers into control group and coke oven group according to their workplaces and the different concentrations of COEs in the environment. We detected 10 urinary PAH metabolites and lung function using gas chromatography-mass spectrometry and spirometric tests, respectively.</p><p><b>RESULTS</b>FEV(1.0) (91.12 ± 13.31) and FEV(1.0)/FVC (108.61 ± 20.37) of the coke oven group is significantly lower than the control group (94.16 ± 15.57, 113.45 ± 19.70). In the coke oven group, the hydroxyphenanthrene and 1-hydroxypyrene are negatively correlated with FEV(1.0)/FVC (β = -0.136, β = -0.100), Ptrend < 0.05 for all.</p><p><b>CONCLUSION</b>The dose response decrease of lung function is associated with the urinary PAH metabolites in coke oven workers. Indicated that the long exposure to PAHs may cause the early lung damage in coke oven workers, phenanthrene and pyrene may be the main factors.</p>

Hydrocarbon degrading microflora in a tropical fuel-contaminated aquifer: assessing the feasibility of PAH bioremediation

An aquifer located within a petroleum processing plant in Moin, Costa Rica, suffers hydrocarbon pollution. This study aimed to determine the ability of indigenous microorganisms from this site to degrade polycyclic aromatic hydrocarbons [PAHs] to evaluate the feasibility of an eventual bioremediation process. Aerobic conditions were found in the aquifer, while microbial analyses of the groundwater indicated the presence of important hydrocarbon-degrading populations. Sixteen PAH-degrading strains were isolated with the ability to grow on naphthalene [5 strains], phenanthrene [3], fluorene [6] and pyrene [2]. Most of the identified isolates belonged to the genus Pseudomonas, although, Comamonas, Sphingomonas Stenotrophomonas and Delftia were also found. A mixture of selected strains was evaluated by its performance of PAH degradation in soil-slurry systems, where efficiency of removal was naphthalene > fluorene > phenanthrene > pyrene. This study is an initial approach to evaluate the feasibility of applying a bioremediation process in the contaminated site

Modification of GSTM1, GSTT1 and GSTP1 gene polymorphisms on urinary 1-hydroxypyrene excretions / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the modification of GSTM1, GSTT1 and GSTP1 gene polymorphisms on urinary 1-hydroxypyrene (1-OHP) excretions in workers under different exposure levels.</p><p><b>METHODS</b>Four hundred and forty-seven occupationally exposed workers from two coking plants and 220 control workers from a wire rod plant were genotyped to analyze the modification of GSTM1, GSTT1 and GSTP1 gene polymorphisms on urinary 1-OHP excretions.</p><p><b>RESULTS</b>The urinary 1-OHP concentration in exposed group was much higher than that in control group (4.61 vs 0.34 µmol/mol Cr, P < 0.05). Occupational exposure levels and cigarette smoking were of the dominating factors affecting 1-OHP excretions in urine. After controlling potential confounders, decreased excretion of urinary 1-OHP was associated with GSTP1 I105V AG + GG genotype in coke oven workers (single-gene model, P = 0.012; multi-gene model, P = 0.011) and with GSTT1 null type in the analysis including all subjects (P = 0.055 in both single-gene and multi-gene models). GSTT1 and GSTP1 were interacted on the urinary concentrations of 1-OHP.</p><p><b>CONCLUSION</b>Urinary 1-OHP concentrations can be modified by GSTM1, GSTT1 and GSTP1 gene polymorphisms, indicating that these genes are involved in the metabolism of polycyclic aromatic hydrocarbons.</p>

A Comparative Study of Nursing Home-Acquired Pneumonia with Community-Acquired Pneumonia / 결핵및호흡기질환

BACKGROUND: Little data is available regarding hospitalized patients with nursing home-acquired pneumonia (NHAP). This is unfortunate because there is an increasing number of elderly persons who are living in nursing homes in Korea. The aim of this study was to compare clinical characteristics and treatment responses of NHAP with community-acquired pneumonia (CAP). METHODS: Patients with pneumonia who were admitted from eight nursing homes or from their own homes were enrolled between May 2007 and April 2009. Their clinical characteristics and treatment responses were reviewed retrospectively, and differences between the two groups were analyzed. RESULTS: Of 110 Patients with pneumonia, 66 (60%) were from nursing homes and their median age was 84. In the NHAP group, functional performance status was significantly poorer, classical symptoms of pneumonia were less severe, and multi-lobe involvement (on chest radiographs) was more frequent than in the CAP group. Patients with NHAP more frequently showed lymphocytopenia, anemia, hypoalbuminemia, hypoxemia, and elevated blood urea nitrogen on admission. The mean CURB-65 score was 2.2 in the NHAP group, higher than 1.7 in the CAP group (p=0.004), and multi-drug resistant pathogens were also highly identified in NHAP group (39% vs. 10%, p=0.036). The mean duration of antibiotic therapy was greater for the NHAP (12.6 days) than for the CAP group (6.6 days) (p<0.001). The mortality rate was 23% in NHAP group, which was significantly higher than 5% in the CAP group (p=0.014). CONCLUSION: NHAP should be more intensively investigated because of the higher frequency of multi-drug resistant pathogens and mortality than the CAP.

Relationship between urinary 1-hydroxypyrene level and peripheral blood lymphocyte chromosomal damage among coke oven workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the urinary 1-hydroxypyrene level and cytokinesis-block micronucleus in peripheral blood lymphocyte in coke oven workers.</p><p><b>METHODS</b>One hundred and fifty-eight workers from a coke plant and 158 referents without occupational PAHs exposure were recruited in this study. Urnary level of 1-hydroxypyrene was measured by alkaline hydrolysis combined with high performance liquid chromatography as an internal exposure dose, and the chromosomal damage of peripheral blood lymphocyte were evaluated with cytokinesis-block micronucleus (CBMN) method. Personal information including occupational history, age, sex, smoking and alcohol drinking, was collected by questionnaire.</p><p><b>RESULTS</b>The lymphocyte chromosomal damage level expressed as frequency of CBMN in coke oven workers was significantly higher than that of controls (3.32 ± 2.90 vs 0.57 ± 0.88, P < 0.01) after adjusting for sex, age, smoking and alcohol drinking, and correlation between urinary 1-hydroxypyrene concentrations and frequency of CBMN was found (Spearman Partial correlation coefficient = 0.28, P < 0.05) in coke oven workers. Three hundreds and sixteen subjects were divided into three groups by their urine 1-hydroxypyrene level (expressed as 0.11 ∼ 0.70, 0.71 ∼ 4.09 and 4.10 ∼ 24.74 µmol/mol Cr). After adjusting for age, sex, smoking and alcohol drinking by multiple nonparametric analysis of covariance, the frequency of CBMN in the groups of 0.71 ∼ 4.09 and 4.10 ∼ 24.74 µmol/mol C were 1.89 ± 2.37 and 3.29 ± 2.36, significantly higher than that in the group of 0 ∼ 0.70 µmol/mol Cr (0.56 ± 0.89).</p><p><b>CONCLUSIONS</b>Under present PAHs exposure levels, the Cytokinesis-block micronucleus test could detect PAHs-induced genotoxicity in coke oven workers.</p>

Association between telomere length and occupational polycyclic aromatic hydrocarbons exposure / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the association between polycyclic aromatic hydrocarbons (PAHs) exposure and telomere length (TL), so as to investigate the effective biomarkers to evaluate the genetic damage in peripheral blood of workers exposed to PAHs.</p><p><b>METHODS</b>The exposure group consisted of 145 coke-oven workers (including 30 top-oven workers, 76 side-oven workers and 39 bottom-oven workers), and the non-exposure control group comprised 68 medical staffs. At 6 hours after the weekend duty shift, the samples of urine and 1 ml venous blood were collected from each subject. Airborne benzene-soluble matter (BSM) and particulate-phase B(a)P in the working environment of coke-oven and controls were sampled and analyzed. The concentration of urinary 1-hydroxypyrene (1-OHPyr) was determined. A real-time PCR method was used to determine the relative telomere length (RTL) of genomic DNA in peripheral blood. The relationship between the RTL and external exposure of PAHs, the potential factors which might have influence on TL were analyzed.</p><p><b>RESULTS</b>The medians of air BSM and particulate-phase B(a)P were higher in coke-oven (BSM: 328.6 µg/m(3); B(a)P: 926.9 ng/m(3)) than those in control working environment (BSM:97.8 µg/m(3); B(a)P: 49.1 ng/m(3)). The level of 1-OHPyr among coke-oven workers was significantly higher than that of non-exposed group (12.2 µmol/mol Cr vs 0.7 µmol/mol Cr; t = 26.971, P < 0.01). RTL in coke-oven workers were significantly shorter than those of controls (1.10 ± 0.75 vs 1.43 ± 1.06; t = 2.263, P = 0.026), and after adjusting for cigarettes per day and urinary 1-OHPyr, the significant difference was still observed (F(adju) = 5.496, P(adju) = 0.020). Stratification analysis found that RTL among the male and non-drinking groups in coke-oven workers were shorter than those the same sex and alcohol using status in controls (1.08 ± 0.73 vs 1.51 ± 1.10, F = 9.212, P = 0.003; 0.96 ± 0.38 vs 1.26 ± 0.46, F = 6.484, P = 0.012). Significant correlation between RTL and age was found (r = -0.284, P = 0.019) in non-exposure group.</p><p><b>CONCLUSION</b>PAH-exposure has effect on TL of genomic DNA in peripheral blood, which is mainly observed in the male and non-drinking groups between PAH-exposed workers and controls. It indicates that TL of genomic DNA in peripheral blood might be an effective biomarker as PAH-induced genetic damage.</p>

Health Effect Assessment on Volunteers Involved in the Cleanup Operation Following the Hebei Spirit Oil Spill Along the Taean Coast, Korea / 대한산업의학회지

OBJECTIVE: The objetive of this study is to assess the level of oxidative stress by the exposure to volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) in volunteers who cleaned up the crude oil spilled from the Hebei Spirit on the Coast of Taean County, Korea. METHODS: The study subjects were 46 volunteers and 37 controls from the National Institute of Environmental Research. A self-administered questionnaire was used for volunteers to examine their working environment and health effects. Urinary concentrations of hippuric acid, 1-hydroxypyrene, and 2-naphthol were measured as exposure markers for VOCs and PAHs, and urinary thiobarbituric acid reactive substances (TBARS) and 8-hydroxydeoxyguanosine (8-OHdG) levels were measured as oxidative stress markers. RESULTS: Sixty-four percent of the respondents presented a variety of symptoms, including sore eyes and throat, nausea, dizziness, headache, low back pain, and leg pain after participating in the cleanup operation. Urinary 2-naphthol and TBARS concentrations appeared higher in the volunteers. Univariate and multivariate analyses showed that urinary TBARS and 8-OHdG levels were positively correlated with urinary 2-naphthol and 1-hydroxypyrene concentrations respectively, especially among the volunteers. CONCLUSIONS: The result implies that participating in cleanup work of oil spills may have a possibility to induce oxidative damage by exposure to PAHs in crude oil.

Degradation of Benzo [a] Pyrene by a novel strain Bacillus subtilis BMT4i (MTCC 9447)

Benzo [a] Pyrene (BaP) is a highly recalcitrant, polycyclic aromatic hydrocarbon (PAH) with high genotoxicity and carcinogenicity. It is formed and released into the environment due to incomplete combustion of fossil fuel and various anthropogenic activities including cigarette smoke and automobile exhausts. The aim of present study is to isolate bacteria which can degrade BaP as a sole source of carbon and energy. We have isolated a novel strain BMT4i (MTCC 9447) of Bacillus subtilis from automobile contaminated soil using BaP (50 ìg /ml) as the sole source of carbon and energy in basal salt mineral (BSM) medium. The growth kinetics of BMT4i was studied using CFU method which revealed that BMT4i is able to survive in BaP-BSM medium up to 40 days attaining its peak growth (10(29) fold increase in cell number) on 7 days of incubation. The BaP degradation kinetics of BMT4i was studied using High Performance Liquid Chromatography (HPLC) analysis of BaP biodegradation products. BMT4i started degrading BaP after 24 hours and continued up to 28 days achieving maximum degradation of approximately 84.66 percent. The above findings inferred that BMT4i is a very efficient degrader of BaP. To our best of knowledge, this is the first report showing utilization of BaP as a sole source of carbon and energy by bacteria. In addition, BMT4i can degrade a wide range of PAHs including naphthalene, anthracene, and dibenzothiophene therefore, it could serve as a better candidate for bioremediation of PAHs contaminated sites.

In vitro activity of thienyl-2-nitropropene compounds against Trypanosoma cruzi

The in vitro activity of four 2-nitropropene derivatives, 1-(3-benzothienyl)-2-nitropropene (N1), 1-(3-thienyl)-2-nitropropene (N2), 1-(5-bromo-2-thienyl)-2-nitropropene (N3) and 1-(4-bromo-2-thienyl)-2-nitropropene (N4), were tested against cultures of the parasite Trypanosoma cruzi. Cytotoxicity studies were performed using Vero cells. The blood trypomastigotes, amastigotes and epimastigotes showed differential degrees of sensitivity towards the four tested compounds; the highest activity against the epimastigotes and blood tripomastigotes was exhibited by N1, followed by N3, N4 and finally N2. In contrast, whereas the compounds N1, N3 and N4 exerted similar magnitudes of activity against amastigotes, N2 was found to be a much less potent compound. According to our results, the compound N1 had the highest level of activity (IC50: 0.6 ìM) against epimastigotes.

Relationship between CYP1A1 gene polymorphisms and urinary 1-hydroxypyrene levels in coke oven workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the associations of CYP1A1 gene polymorphisms with levels of urinary 1-hydroxypyrene among coke oven workers.</p><p><b>METHODS</b>223 male workers from a coke plant (76, 82 and 65 workers in oven top group, oven-side group and oven-bottom group respectively) and 119 controls without occupational polycyclic aromatic hydrocarbons exposure were selected. The MspI gene polymorphism in CYP1A1 3' flanking region and the genotypes at I462V site in exon 7 of CYP1A1 were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele specific amplification (ASA).</p><p><b>RESULTS</b>The urinary 1-hydroxypyrene of coke oven workers in oven-top, oven-side and oven-bottom (3.77+/-0.64, 3.57+/-0.49, 3.26+/-0.80 micromol/mol Cr) were significantly higher than controls (2.80+/-1.02 micromol/mol Cr) (P<0.01). The urinary 1-hydroxypyrene was not significantly different among MspI genotypes in CYP1A1 3' flanking region (P>0.05). In oven-top group and oven-side group, the subjects with Val/Val genotype in exon 7 of CYP1A1 had significantly higher urinary 1-hydroxypyrene levels than those with Ile/Val or Ile/Ile genotype, and urinary 1-hydroxypyrene of Ile-Val genotype were also significantly higher than Ile/Ile genotype (P<0.01). Multivariate logistic regression analysis showed that the coke oven workers (OR in oven top group, oven-side group and oven-bottom group was 24.926, 4.226 and 6.729 respectively) and subjects with m2/m2 genotype in CYP1A1 3' flanking region (OR=4.031) or with Val/Val or Ile/Val genotype in exon 7 of CYP1A1 (OR were 5.524 and 3.811) had elevated urinary 1-hydroxypyrene (greater than 95 percentile of control group, 3.876 micromol/mol Cr).</p><p><b>CONCLUSION</b>BAP concentration of work environment contributes to the elevated urinary 1-hydroxypyrene levels, and the exposed BAP levels were regulated by the CYP1A1 MspI and I462V genotypes. Genetic polymorphism of CYP1A1 gene could be a susceptible biomarker in coke oven workers which was involved in the individual susceptibility on metabolism of PAHs.</p>

Remediation of soil co-contaminated with pyrene and cadmium by growing maize [Zea mays L.]

Sites co-contaminated with organic and metal pollutants are common and considered to be a more complex problem as the two components often causes a synergistic effect on cytotoxicity. Phytoremediation has been proposed as a cost-effective technology for treating heavy metal or organic contamination and may be suitable for remediation of co-contaminated soil. This study investigated theconcurrent removal of pyrene and cadmium in co-contaminated soil by growing maize in a pot experiment. At the end of 60 day culture, pyrene in spiked soil diminished significantly, accounting for 21-31% of the initial extractable concentration in unplanted soil and 12-27% in planted soil. With the increment of cadmium level, the residual pyrene both in unplanted and planted soil tended to increase. Although the presence of cadmium increased the accumulation of pyrene in maize, plant accumulation only account for less than 0.30% of the total amount of the dissipated pyrene in vegetated soils. It implied that plant-promoted microbial biodegradation was the predominant contribution to the plant-enhanced dissipation of pyrene in co-contaminated soil. Unlike pyrene, heavy metal cadmium cannot be degraded. It was observed that maize can concurrently removed about on the average 0.70% of the total cadmium amount in soil by plant uptake, but Cd phytoextraction would be inhibited under contamination of pyrene. Maize CT38 can normally grow in the co-contaminated soil with high level Cd and pyrene and can effectively remedy the sites co-contaminated with these two types of contamination, which suggest the possibility of simultaneous phytoremediation of two different contaminant types

Determination of lead, naphthalene, phenanthrene, anthracene and pyrene in street dust

Street dust is a potential source of lead exposure to humans, however scarce information about the pollution levels with lead and polyromatic hydrocarbons exists in Venezuela, limiting the appropriate evaluation of the levels of risk of the people. This work was aimed in the determination of the concentrations of lead, naphtalene, anthracene, phenanthrene and pyrene in the street dust of the most transited avenues and streets of Maracay city. Thirty street dust samples were collected at the streets and avenues, troll and bus main station. Lead was determined by atomic absorption spectrometry after acid digestion [Pb-total], also the fractions of lead soluble in 1 M MgCI2 and 0.5 M ammonium acetate [pH = 7] were quantified. The polyaromatic hydrocarbons concentrations were determined by capillary gas chromatography equipped with a flame ionization detector. The Pb-total ranged between 734 and 11.439 micro g/g with the higher values at the most transited streets and avenues. About 60% of samples exhibited concentrations between 1.000 and 2.500 micro g/g, similar to the values reported in the literature for soils of urban areas. The fraction of lead soluble in magnesium accounted for less than 3% of Pb-Total, while the 0.5 M ammonium acetate solution represented more than the 75% of the total loads of the pollutant. The most contaminated samples were those taken at the toll with concentrations of 695.5 and 252.1 micro g/g phenanthrene and anthracene were the most abundant, while at the bus station all compounds were detected

Relationship between aryl hydrocarbon receptor G1661A gene polymorphism and level of urinary 1-hydroxypyrene of coke oven workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the relationship between polymorphism of aryl hydrocarbon receptor (AhR) gene in G1661A and the level of urinary 1-hydroxypyrene among coke oven workers.</p><p><b>METHODS</b>295 male subjects were studied, including 214 workers working in coke oven plant and 81 controls working in raw material plant who were not generally exposed to polycyclic aromatic hydrocarbons occupationally. General in-formation of subjects were collected in a specific questionnaire including age, smoking and drinking habits, the history of occupation and so on. The AhR genotypes were detected by allele specific amplification (ASA), and the levels of urinary 1-hydroxypyrene were measured by high performance liquid chromatography with a fluorescence detector.</p><p><b>RESULTS</b>The frequencies of G/G, G/A and A/A genotype were 52.8% (113/214), 27.6% (59/214) and 19.6% (42/214) in exposed group and 67.9% (55/81), 19.8% (16/81) and 12.3% (10/81) in control group, respectively. No significant difference was found in three genotypes between the exposed and control group. Allele frequencies of G and A were 66.6% (285/428) and 33.4% (143/428) in exposed group and 77.8% (126/162) and 22.2% (36/162) in control group, and no statistical differences were found in allele frequency between exposed and control group. After the length of service and external exposure orders in general linear model were adjusted, results of covariance analysis showed that logarithmic transformed urinary 1-hydroxypyrene levels were (3.62 +/- 0.12), (3.43 +/- 0.12) and (3.44 +/- 0.08) micromol/mol Cr in individuals with A/A, G/A and G/G, respectively. The logarithmic transformed urinary 1-hydroxypyrene levels were (3.24 +/- 0.09) and (3.43 +/- 0.10) micromol/mol Cr in individuals with allele of G and A. No statistical differences were found in level of 1-hydroxypyrene among A/A, G/A and G/G genotype individuals, and between allele G and allele A after external exposure orders and length of service were adjusted.</p><p><b>CONCLUSION</b>The polymorphism of aryl hydrocarbon receptor G1661A has no significant impact on levels of urinary 1-hydroxypyrene.</p>