Toxicology Commons^™

Numerical Simulations Of In Vitro Nanoparticle Toxicity – The Case Of Poly(Amido Amine) Dendrimers., Marcus Maher, Pratap Naha, Sourav Prasanna Mukherjee, Hugh Byrne

Articles

A phenomenological rate equation model is constructed to numerically simulate nanoparticle uptake and subsequent cellular response. Polyamidoamine dendrimers (generations 4-6) are modelled and the temporal evolution of the intracellular cascade of; increased levels of reactive oxygen species, intracellular antioxidant species, caspase activation, mitochondrial membrane potential decay, tumour necrosis factor and interleukin generation is simulated, based on experimental observations.

The dose and generation dependence of several of these response factors are seen to well represent experimental observations at a range of time points. The model indicates that variations between responses of different cell-lines, including murine macrophages, human keratinocytes and colon cells, …

Interactive Effects Of Climate Change With Nutrients, Mercury, And Freshwater Acidification On Key Taxa In The North Atlantic Landscape Conservation Cooperative Region, Alfred E. Pinkey, Charles T. Driscoll, David C. Evers, Michael J. Hooper, Jeffrey Horan, Jess W. Jones, Rebecca S. Lazarus, Harold G. Marshall, Andrew Milliken, Barnett A. Rattner, John Schmerfold, Donald W. Sparling

Biological Sciences Faculty Publications

The North Atlantic Landscape Conservation Cooperative LCC (NA LCC) is a public-private partnership that provides information to support conservation decisions that may be affected by global climate change (GCC) and other threats. The NA LCC region extends from southeast Virginia to the Canadian Maritime Provinces. Within this region, the US National Climate Assessment documented increases in air temperature, total precipitation, frequency of heavy precipitation events, and rising sea level, and predicted more drastic changes. Here, we synthesize literature on the effects of GCC interacting with selected contaminant, nutrient, and environmental processes to adversely affect natural resources within this region. Using …

Mechanisms Of Arsenic Detoxification And Resistance, Jitesh Kannan Pillai

FIU Electronic Theses and Dissertations

Arsenic is a ubiquitous environmental toxic substance. As a consequence of continual exposure to arsenic, nearly every organism, from Escherichia coli to humans have evolved arsenic detoxification pathways. One of the pathways is extrusion of arsenic from inside the cells, thereby conferring resistance. The R773 arsRDABC operon in E. coli encodes an ArsAB efflux pump that confers resistance to arsenite. ArsA is the catalytic subunit of the pump, while ArsB forms the oxyanion conducting pathway. ArsD is an arsenite metallochaperone that binds arsenite and transfers it to ArsA. The interaction of ArsA and ArsD allows for resistance to As(III) at …

Acid-Base Properties Of The Adsorption Of Synthetic Dyes From Solutions, Rada-Mayya Kostadinova, Gabriela Sikorska, Michelle Naidoo, Abel E. Navarro

Publications and Research

The presence of synthetic dyes is often underestimated in environmental protection. However, it has been demonstrated the impact of colored compounds in ecology and human health. Green tea (GT) and peppermint (PM) tea bag wastes were used as potential adsorbents of dyes from aqueous solutions to evaluate the effect of pH on the adsorption. Basic yellow 57, basic blue 99 and crystal violet were chosen as model dyes due to their widespread use in the industry. Dye solutions at different pH values were placed in contact with the adsorbents in batch experiments at room temperature. Results indicate that crystal violet …

Possible Pro-Carcinogenic Association Of Endotoxin On Lung Cancer Among Shanghai Women Textile Workers, H. Checkoway, J. I. Lundin, S. Costello, R. Ray, W. Li, E. A. Eisen, G. Astrakianakis, N. Seixas, Katie M. Applebaum, D. L. Gao, D. B. Thomas

Environmental and Occupational Health Faculty Publications

Background:

Endotoxin (lipopolysaccharide) is a widespread contaminant in many environmental settings. Since the 1970s, there has been generally consistent evidence indicating reduced risks for lung cancer associated with occupational endotoxin exposure.

Methods:

We updated a case–cohort study nested within a cohort of 267 400 female textile workers in Shanghai, China. We compared exposure histories of 1456 incident lung cancers cases diagnosed during 1989–2006 with those of a reference subcohort of 3022 workers who were free of lung cancer at the end of follow-up. We applied Cox proportional hazards modelling to estimate exposure–response trends, adjusted for age and smoking, for cumulative …

Candy Flavorings In Tobacco, Jessica E. Brown, Wentai Luo, Lorne M. Isabelle, James F. Pankow

Chemistry Faculty Publications and Presentations

Professor James F. Pankow reveals striking similarities between the patterns in the flavoring chemicals used in flavored tobacco products and those in popular candy and Kool-Aid products. The authors analyzed 12 artificially flavored candy and fruit drink products and compared them to 15 widely-available flavored tobacco products. They found significant overlap in the chemical signatures of the flavor chemicals. Several of the tobacco products contained flavor chemicals at much higher concentrations than in the non-tobacco products.

Speciation, Metabolism, Toxicity, And Protein-Binding Of Different Arsenic Species In Human Cells, Szabina A. Stice

FIU Electronic Theses and Dissertations

Despite of its known toxicity and potential to cause cancer, arsenic has been proven to be a very important tool for the treatment of various refractory neoplasms. One of the promising arsenic-containing chemotherapeutic agents in clinical trials is Darinaparsin (dimethylarsinous glutathione, DMA^III(GS)). In order to understand its toxicity and therapeutic efficacy, the metabolism of Darinaparsin in human cancer cells was evaluated. With the aim of detecting all potential intermediates and final products of the biotransformation of Darinaparsin and other arsenicals, an analytical method employing high performance liquid chromatography inductively coupled mass spectrometry (HPLC-ICP-MS) was developed. This method was …

Re: Pierce Et Al. Diacetyl And 2,3-Pentanedione Exposures Associated With Cigarette Smoking: Implications For Risk Assessment Of Food And Flavoring Workers Crit Rev Toxicol, 2014; 44(5): 420-435, Muge Akpinar-Elci, Omur Cinar Elci

Center for Global Health Publications

We were greatly dismayed by Pierce et al.’ s report on the associations between exposure to Diacetyl and 2,3-pentanedione and cigarette smoking (Pierce et al. 2014). It stated that “ Diacetyl and 2,3-pentanedione exposures from cigarette smoking far exceed occupational exposures for most food/flavoring workers who smoke. ” Based on this finding, the authors suggested that “ previous claims of a significant exposure – response relationship between diacetyl inhalation and respiratory disease in food/flavoring workers were confounded because none of the investigations considered or quantified the non-occupational diacetyl exposure from cigarette smoke, yet all the cohorts evaluated had considerable smoking …

Epoxy Resin Monomers With Reduced Skin Sensitizing Potency, Niamh F. O'Boyle, Ida B. Niklasson, Ali R. Tehrani-Bagda, Tamara Delaine, Krister Holmberg, Kristina Luthman, Ann-Therese Karlberg

Articles

Epoxy resin monomers, including diglycidyl ethers of bisphenol A and F (DGEBA and DGEBF), are extensively used as building blocks for thermosetting polymers. However, they are known to cause widespread contact allergy. This research describes a number of alternative epoxy resin monomers, designed with the aim of reducing the skin sensitizing potency whilst maintaining the ability to form thermosetting polymers. The compounds were designed, synthesized, assessed for skin sensitizing potency using the in vivo murine local lymph node assay, and tested for technical applicability using thermogravimetric analysis and differential scanning calorimetry. All the novel epoxy resin monomers had decreased skin …

Concern-Driven Integrated Toxicity Testing Strategies For Nanomaterials - Report Of The Nanosafety Cluster Working Group 10, Hugh Byrne, Agnes G. Oomen, Peter M.J. Bos, Teresa F. Fernandes, Kerstin Hund-Rinke, Diana Boraschi, Karin Aschberger, Stefania Gottardo, Frank Von Der Kammer, Dana Kühnel, Danail Hristozov, Antonio Marcomini, Lucia Migliore

Articles

Bringing together topic-related European Union-(EU)-funded projects, the so-called “NanoSafety Cluster” aims at identifying key areas for further research on risk assessment procedures for nanomaterials (NM). The outcome of NanoSafety Cluster Working Group 10, this commentary presents a vision for concern-driven integrated approaches for the (eco-)toxicological testing and assessment (IATA) of NM. Such approaches should start out by determining concerns, i.e. specific information needs for a given NM based on realistic exposure scenarios. Recognized concerns can be addressed in a set of tiers using standardized protocols for NM preparation and testing. Tier 1 includes determining physico-chemical properties, non-testing (e.g. structure …