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Exposure to polycyclic aromatic hydrocarbons and phthalates are linked to lung function decline and altered relative telomere length (RTL) accompanying with oxidative stress and inflammatory events in human body. However, limited data are available about impacts of co-exposure of PAHs and phthalates on lung function and RTL. We conducted a pilot study with repeated measures during the winter of 2014 and summer of 2015 in Wuhan city, China. Participants took part in the measures of lung function, RTL, urinary monohydroxylated-PAHs (OH-PAHs) and phthalate metabolites over three consecutive days in each season. Linear mixed-effect (LME) models and Bayesian kernel machine regression (BKMR) were used to analyze the relations of OH-PAHs or phthalate metabolites with lung function or RTL. LME models showed the negative associations of 3-day average of hydroxyphenanthrene (2 + 3-, 4-OHPhe) or 1-hydroxypyrene with FEV1, 3-day average of 2 + 3-OHPhe with FVC. BKMR models revealed the negative relation of eight OH-PAHs with FEV1, FVC or RTL; nine phthalate metabolites may counteract an overall effect of eight OH-PAHs on FEV1, FVC or RTL. The findings indicated that urinary phthalate metabolites may counteract the negative association of urinary OH-PAHs on FEV1 or FVC, which may be partially linked to shorter RTL regarding biological aging., Competing Interests: Declaration of Competing Interest None declare., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Complex mixture exposures, such as those associated with water sources, are an important issue in health risk assessment. This study assessed the cytotoxicity of chemical mixtures extracted from water sources in regions of the Huai River Basin with high cancer incidences and built statistical models of cytotoxicity based on pollution profiles that were measured with gas chromatography-mass spectrometry (GC-MS). Both surface and ground waters were collected from rural water sources of Shenqiu County, Henan Province of China from 2008 to 2011 and extracted with XAD-2 resigns. Cytotoxicity was evaluated with Chinese hamster ovary K1 (CHO-K1) cells and compared against the pollution profiles of the extracts. IC50 of water samples ranged from 0.023 to 0.338L-eq/mL. The pollutants in waters determined by GC-MS are complex and some of the compounds that contributed to cytotoxicity lack toxicity data. A partial least squares (PLS) regression model of cytotoxicity was built based on linear aggregation of predictor variables (i.e., peaks for single compounds in the gas chromatograms). The PLS model contains 2 PLS factors extracted from 141 variables. The model was validated internally with training data permutation and externally with a test sample. The model explained 92% of the cytotoxicity in the training samples and 40% in the test sample. This approach provides a general, rapid method for relating water toxicity to GC-MS chromatograms and for predicting the compounds that contribute most to toxicity., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A resazurin method was employed to test and compare cytotoxicity of extracts from fruiting bodies, insects and cultured mycelia of Cordyceps formosana against Chinese hamster ovary (CHO) cells. Results showed that the cultured mycelia had much stronger cytotoxicity than that of the fruiting bodies and infected insects. This suggests that using cultured mycelia to substitute a natural Cordyceps may result in poisoning. A combined method of HPLC-PAD-HRMS and cytotoxic analysis revealed that the most toxic compound (Compound 1) was found mainly in the cultured mycelia and also a small amount in the infected insect body of the Cordyceps, but not in the fruiting body. The second toxic compound (Compound 2) was found in all structures of Cordyceps and in cultured mycelia. Different contents of the toxic compounds resulted in the different cytotoxicity of the extracts. Compound 1 and Compound 2 were prepared with preparative HPLC as yellow and orange powders, respectively. Cytotoxic tests showed that the median lethal dose (LD₅₀) against CHO cells of Compound 1 was 18.3 ± 0.2 and 103.7 ± 5.9 μg/mL for Compound 2. Compound 1 and Compound 2 were identified as rugulosin and skyrin by HRMS, UV and NMR data. The two compounds were never previously isolated from the genera Cordyceps and Hirsutella and their cytotoxicity against CHO cells was also reported for the first time., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Powerful, robust in silico approaches offer great promise for classifying and predicting biological effects of complex mixtures and for identifying the constituents of greatest concern. Support vector machine (SVM) methods can deal with high dimensional data and small sample size and examine multiple interrelationships among samples. In this work, we applied SVM methods to examine pollution profiles and mutagenicity of 60 water samples obtained from 6 cities in China during 2006-2011. Pollutant profiles were characterized in water extracts by gas chromatography-mass spectrometry (GC/MS) and mutagenicity examined by Ames assays. We encoded feature vectors of GS-MS peaks in the mixtures and used 48 samples as the training set, reserving 12 samples as the test set. The SVM model and regression were constructed from whole pollution profiles that ranked compounds in relation to their correlation to the mutagenicity. Both classification and prediction performance were evaluated. The SVM model based on whole pollution profiles showed lower performance (sensitivity, specificity, accuracy and correlation coefficient were 69.5-70.7%, 70.6-73.2%, 69.9-72.1%, and 0.55-0.59%, respectively) than one based on compounds with highest association with mutagenicity. A SVM model with the top 10 compounds had the highest performance (sensitivity, specificity, accuracy, and correlation coefficient were 89.8-90.3%, 90.1-92.1%, 90.1-91.3%, and 0.80-0.82%, respectively), with negligible decreases in performance between the test and training set. SVM can be a powerful, robust classifier of the relationship of pollutants and mutagenicity in complex real-world mixtures. The top 14 compounds have the greatest contribution to mutagenicity and deserve further studies to identify these constituents., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

It is generally known that there are many endocrine disrupting compounds (EDCs) in the effluents from wastewater treatment plants (WWTPs). Most research has focused on the occurrence of estrogenic or androgenic activities, while ignoring that there are environmental chemicals disrupting thyroid system, which is essential for growth and development in both humans and animals. In the present work, a two-hybrid yeast assay was conducted to evaluate the removal efficiencies of agonistic or antagonistic thyroid receptor (TR) mediated effects in different treatment processes of three WWTPs located in Beijing. We found no TR agonistic, but TR antagonistic activities in all processes from the WWTPs. The TR antagonistic activities in organic extracts of water samples were then calibrated regarding to a known TR-inhibitor, amiodarone hydrochloride (AH). The observed concentration of TR disrupting substances ranged from 2.35 x 10(-8) to 6.19 x 10(-7) mol/L AH in Gaobeidian WWTP, 3.76 x 10(-8) to 8.75 x 10(-8) mol/L AH in Lugouqiao WWTP, and 4.80 x 10(-9) to 2.55 x 10(-8) mol/L AH in Beixiaohe WWTP. Of the three WWTPs, the removal rates were 92.7%, 42.2%, and 23.1% respectively. Industrial sewage may contain more TR disrupting substances compared with domestic sewage. The recipient waters were found to contain considerable concentrations of TR disrupting substances that may cause adverse effects on the exposed organisms.