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The in vivo genotoxic potential of bisphenol A using the comet assay in mice and in human sperm cells in vitro without metabolizing enzymes was studied. Male mice were exposed by oral gavage to the following doses of bisphenol A (0 125, 250 and 500 mg/kg body weight). DNA damage was investigated in liver, kidney, testes, urinary bladder, colon and lungs cells. In testicular cells, a significant increase in DNA strand breaks was observed in the lowest, but not in the medium or highest dose groups. Histopathological investigation of the testicular samples did not show any treatment dose-related effects. No DNA strand breaks were observed in any of the other investigated tissues. In human sperm cells in vitro, bisphenol A did not induce DNA strand breaks. [ABSTRACT FROM AUTHOR]

• RCC reduction techniques in the houses like load bearing constructions address EW. • Exposed brick masonry and speedy constructions boost EW management. • Steel, cement, and brick are not the prime-most embodied water consumers. • The results seek attention as it finds embodied and operational water almost equal. • Energy related embodied water is negligible in post material production phase. • The study identifies various EW impacting parameters much beyond A+D only. The study assesses the embodied water (EW) of conventional masonry houses in Jammu, India. The research uses material inventory, site investigations, and hybrid EW coefficients in the hybrid process-based ISO 14046 LCA study. It carries improvised system boundary analysis to infer the disaggregated, aggregated results using descriptive statistics (frequency analysis) and regression. The study finds high aggregated EW at 43.7 KL/m2 with materials EW (EW MAT.), in-direct water (IDW), and direct water (DW) components of 51.26%, 40.34%, and 8.38%. The study infers (i) EW is equally important (97%) as the operational water, (ii) sand, aggregates, DW, and finishing materials impact EW more than typical cement, brick, and steel (iii) The unprioritized labor meals and DW are significant and seeks construction management (iv) off-site (pre-cast) construction, and transportation is not a barrier to EW as energy-related EW is negligible. The results identify EW as a multi-faceted issue requiring a collaborative stakeholders' approach than Architecture + Design (A+D) and construction optimizations. The analysis implies the importance of load-bearing constructions in low-rise houses, exposed masonry, alternatives to wall finishes and aggregates, adaptive reuse, and RCC reduction-based A+D. The four houses based solitary study breakthrough a canvas of issues to capitalize EW agenda further. [ABSTRACT FROM AUTHOR]

The in vivo Comet assay is a sensitive method for evaluating DNA damage. A recurrent concern is how to analyze the data appropriately and efficiently. A popular approach is to summarize the raw data into a summary statistic prior to the statistical analysis. However, consensus on which summary statistic to use has yet to be reached. Another important consideration concerns the assessment of proper sample sizes in the design of Comet assay studies. This study aims to identify a statistic suitably summarizing the % tail DNA of mice testicular samples in Comet assay studies. A second aim is to provide curves for this statistic outlining the number of animals and gels to use. The current study was based on 11 compounds administered via oral gavage in three doses to male mice: CAS no. 110-26-9, CAS no. 512-56-1, CAS no. 111873-33-7, CAS no. 79-94-7, CAS no. 115-96-8, CAS no. 598-55-0, CAS no. 636-97-5, CAS no. 85-28-9, CAS no. 13674-87-8, CAS no. 43100-38-5 and CAS no. 60965-26-6. Testicular cells were examined using the alkaline version of the Comet assay and the DNA damage was quantified as % tail DNA using a fully automatic scoring system. From the raw data 23 summary statistics were examined. A linear mixed-effects model was fitted to the summarized data and the estimated variance components were used to generate power curves as a function of sample size. The statistic that most appropriately summarized the within-sample distributions was the median of the log-transformed data, as it most consistently conformed to the assumptions of the statistical model. Power curves for 1.5-, 2-, and 2.5-fold changes of the highest dose group compared to the control group when 50 and 100 cells were scored per gel are provided to aid in the design of future Comet assay studies on testicular cells. [ABSTRACT FROM AUTHOR]

Abstract: The impact on the sensitivity of the in vitro comet assay by increasing the number of cells scored has only been addressed in a few studies. The present study investigated whether the sensitivity of the assay could be improved by scoring more than 100 cells. Two cell lines and three different chemicals were used: Caco-2 cells were exposed to ethylmethane sulfonate and hydrogen peroxide in three concentrations, and HepG2 cells were exposed to ethylmethane sulfonate, hydrogen peroxide and benzo[a]pyrene in up to four concentrations, in four to five independent experiments. The scoring was carried out by means of a fully automated scoring system and the results were analyzed by evaluating the % tail DNA of 100–700 randomly selected cells for each slide consisting of two gels. By increasing the number of cells scored, the coefficients of variance decreased, leading to an improved sensitivity of the assay. A two-way ANOVA analysis of variance showed that the contribution from the two variables “the number of cells scored” and “concentration” on the total variation in the coefficients of variance dataset was statistically significant (p <0.05). The increase in sensitivity was demonstrated by the possibility to detect an increase in % tail DNA with statistical significance at lower concentrations. The results indicated that for low levels of DNA damage, below 9% tail DNA, scoring of 600 cells increased the sensitivity compared with scoring of 100 cells. For relatively low levels of DNA damage, about 9–16% tail DNA, scoring of 300 cells increased the sensitivity. Thus, the recommendation for the optimum number of cells scored would be 600 and 300 for low and relatively low levels of DNA damage, respectively. The findings from this study could be particularly important for bio-monitoring studies where small differences in DNA-damage levels could be relevant. [Copyright &y& Elsevier]

Abstract: The natural clay mineral montmorillonite (Cloisite® Na+) and an organo-modified montmorillonite (Cloisite® 30B) were investigated for genotoxic potential as crude suspensions and as suspensions filtrated through a 0.2-μm pore-size filter to remove particles above the nanometre range. Filtered and unfiltered water suspensions of both clays did not induce mutations in the Salmonella/microsome assay at concentrations up to 141μg/ml of the crude clay, using the tester strains TA98 and TA100. Filtered and unfiltered Cloisite® Na+ suspensions in culture medium did not induce DNA strand-breaks in Caco-2 cells after 24h of exposure, as tested in the alkaline comet assay. However, both the filtered and the unfiltered samples of Cloisite® 30B induced DNA strand-breaks in a concentration-dependent manner and the two highest test concentrations produced statistically significantly different results from those seen with control samples (p <0.01 and p <0.001) and (p <0.05 and p <0.01), respectively. The unfiltered samples were tested up to concentrations of 170μg/ml and the filtered samples up to 216μg/ml before filtration. When tested in the same concentration range as used in the comet assay, none of the clays produced ROS in a cell-free test system (the DCFH-DA assay). Inductively coupled plasma mass-spectrometry (ICP-MS) was used to detect clay particles in the filtered samples using aluminium as a tracer element characteristic to clay. The results indicated that clay particles were absent in the filtered samples, which was independently confirmed by dynamic light-scattering measurements. Detection and identification of free quaternary ammonium modifier in the filtered sample was carried out by HPLC-Q-TOF/MS and revealed a total concentration of a mixture of quaternary ammonium analogues of 1.57μg/ml. These findings suggest that the genotoxicity of organo-modified montmorillonite was caused by the organo-modifier. The detected organo-modifier mixture was synthesized and comet-assay results showed that the genotoxic potency of this synthesized organo-modifier was in the same order of magnitude at equimolar concentrations of organo-modifier in filtrated Cloisite® 30B suspensions, and could therefore at least partly explain the genotoxic effect of Cloisite® 30B. [Copyright &y& Elsevier]

Abstract: Airborne particulate matter (PM) was sampled by use of an electrostatic sampler in an oven hall and a receiving hall in a waste-incineration energy plant, and from urban air in a heavy-traffic street and from background air in Copenhagen. PM was sampled for 1–2 weeks, four samples at each site. The samples were extracted and examined for mutagenicity in Salmonella typhimurium strains TA98, YG1041 and YG5161, for content of inorganic elements and for the presence of eight polycyclic aromatic hydrocarbons. The induction of IL-6 and IL-8 mRNA expression and the presence of DNA damage – tested by the comet assay – were determined after 24-h incubations with human A549 lung epithelial cells. The PM2.5 concentration was about twofold greater in the oven hall than in the receiving hall. The particle size distribution in the receiving hall was similar to that in street air (maximum mode at about 25nm), but the distribution was completely different in the oven hall (maximum mode at about 150nm). Also chemically, the samples from the oven hall were highly different from the other samples. PM extracts from the receiving hall, street and background air were more mutagenic than the PM extracts from the oven hall. PM from all four sites caused similar levels of DNA damage in A549 cells; only the oven hall samples gave results that were statistically significantly different from those obtained with street-air samples. The receiving hall and the urban air samples were similarly inflammatory (relative IL-8 mRNA expression), whereas the oven hall did not cause a statistically significant increase in IL-8 mRNA expression. A principal component analysis separated the oven hall and the receiving hall by the first principal component. These two sites were separated from street and background air with the second principal component. Several clusters of constituents were identified. One cluster consisted of all the polycyclic aromatic hydrocarbons (PAH), several groups of metals and one group of the biological endpoints (DNA damage, IL-6 and IL-8 mRNA expression). The PAH and the inorganic content of the air in the receiving hall may be due to vehicle emissions and suspended waste particles. The inorganic content in the street and background air may have been influenced by break wear, road emissions and long-range transport. The results from a partial least-square regression analysis predicted that both PAHs and a group of metals including Fe and Mn contributed to IL-6 and IL-8 induction. Only Mn and Sr were predicted to influence DNA damage statistically significantly. Among the PAHs only chrysene had influence on DNA damage. The PM from the oven hall was markedly different from the PM at other locations in particle size distribution, chemical composition and the resulting biological effects when A549 cells were incubated with the PM. These characteristics and observations in the oven hall indicated that the PM source was oven exhaust, which was well combusted. [Copyright &y& Elsevier]

An extensive literature search to identify and collect studies related to the toxicity of grayanotoxins and 5‐hydroxymethylfurfural (5‐HMF) was performed in the three databases PubMed, Web of Science and SciFinder® for six and four Areas, respectively. After combination of the searches from the three databases and removal of the duplicates, the total number of references for the grayanotoxins was 652 and for 5‐HMF Area 1b was 3,862, for Area 2b was 37, for Area 3b was 221 and for Area 4b was 500. The evaluation of all retrieved references for relevance by screening the title and abstract (if available) and applying eligibility criteria (inclusion/exclusion) resulted in a total number of relevant references for the grayanotoxins for Area 1a of 71, for Area 2a of 3, for Area 3a of 5, for Area 4a of 75, for Area 5a of 141, and for Area 6a of 78 and for 5‐HMF for Area 1b of 55, for Area 2b of 14, for Area 3b of 15 and for Area 4b of 8. [ABSTRACT FROM AUTHOR]

An extensive literature search to identify and collect studies related to the toxicity of polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA) and brominated phenols (BPs) was performed in the three databases PubMed, Web of Science and SciFinder® for four Areas. After combination of the searches from the three databases and removal of the duplicates, the total number of references for Area 1 was 6,231, for Area 2 was 8,236, for Area 3 was 4,994 and for Area 4 was 6,363. The evaluation of all retrieved references for relevance by screening the title and abstract (if available) and applying eligibility criteria (inclusion/exclusion) resulted in a total number of relevant references for Area 1 of 378 (PBDEs), 46 (TBBPA) and 29 (BPs), for Area 2 of 188 (PBDEs), 37 (TBBPA) and 4 (BPs), for Area 3 of 518 (PBDEs), 180 (TBBPA) and 49 (BPs), and for Area 4 of 717 (PBDEs), 59 (TBBPA) and 18 (BPs). [ABSTRACT FROM AUTHOR]

While regulatory requirements for carcinogenicity testing of chemicals vary according to product sector and regulatory jurisdiction, the standard approach starts with a battery of genotoxicity tests (which include mutagenicity assays). If any of the in vivo genotoxicity tests are positive, a lifetime rodent cancer bioassay may be requested, but under most chemical regulations (except plant protection, biocides, pharmaceuticals), this is rare. The decision to conduct further testing based on genotoxicity test outcomes creates a regulatory gap for the identification of non-genotoxic carcinogens (NGTxC). With the objective of addressing this gap, in 2016, the Organization of Economic Cooperation and Development (OECD) established an expert group to develop an integrated approach to the testing and assessment (IATA) of NGTxC. Through that work, a definition of NGTxC in a regulatory context was agreed. Using the adverse outcome pathway (AOP) concept, various cancer models were developed, and overarching mechanisms and modes of action were identified. After further refining and structuring with respect to the common hallmarks of cancer and knowing that NGTxC act through a large variety of specific mechanisms, with cell proliferation commonly being a unifying element, it became evident that a panel of tests covering multiple biological traits will be needed to populate the IATA. Consequently, in addition to literature and database investigation, the OECD opened a call for relevant assays in 2018 to receive suggestions. Here, we report on the definition of NGTxC, on the development of the overarching NGTxC IATA, and on the development of ranking parameters to evaluate the assays. Ultimately the intent is to select the best scoring assays for integration in an NGTxC IATA to better identify carcinogens and reduce public health hazards. [ABSTRACT FROM AUTHOR]

An extensive literature search to identify and collect all studies related to fumonisins and their modified forms was performed in the two databases PubMed and Web of Science for nine Areas. After combination of the searches from the two databases and removal of the duplicates, the total number of hits for Area 1 was 4456, for Area 2 was 2261, for Area 3 was 1649, for Area 4 was 3555, for Area 5 was 1632, for Area 6 was 2424, for Area 7 was 5087, for Area 8 was 3284, and for Area 9 was 3283. The evaluation of all retrieved references for relevance by screening the title and abstract (if available) and applying eligibility criteria (inclusion/exclusion) resulted in a total number of relevant references for Area 1 of 532, for Area 2 of 114, for Area 3 of 273, for Area 4 of 87, for Area 5 of 138, for Area 6 of 38, for Area 7 of 270, for Area 8 of 709, and for Area 9 of 270. This publication is linked to the following EFSA Journal article: http://onlinelibrary.wiley.com/doi/10.2903/j.efsa.2018.5172/full [ABSTRACT FROM AUTHOR]