Comparison of Acute Toxicity and Genotoxic Concentrations of Single Compounds and Waste Elutriates Using the Microtox/Mutatox Test System

The role of CYP1A inhibition in the embryotoxic interactions between hypoxia and polycyclic aromatic hydrocarbons (PAHs) and PAH mixtures in zebrafish (Danio rerio)

“…Compared to BaP, PY metabolism appears to be relatively simple with most of the parent pyrene being converted to 1-hydroxypyrene (1-HP) (Law et al 1994). While 1-HP has been reported to be mutagenic and toxic to natural microbial assemblages and nematodes (Lambert et al 1995; Hauser et al 1997; Hwang et al 2001), a literature search uncovered no reports of toxicity of 1-hydroxypyrene to fish. The identity of the pyrene species responsible for its embryotoxicity remains unclear; however, it appears that hypoxia may inhibit its formation by inhibiting CYP1A activity.…”

Liquid chromatography–mass spectrometry analysis of hydroxylated polycyclic aromatic hydrocarbons, formed in a simulator of the human gastrointestinal tract

“…The liquid chromatography-mass spectrometry (LC-MS) methods have utilized atmospheric pressure chemical ionization (APCI) or electrospray ionization (ESI) in both positive and negative ionization mode to screen for hydroxylated PAH compounds [15,16]. However reported detection limits of around 0.5 g ml −1 are relatively high when taking into account that concentrations in the range 0.039-2.5 g ml −1 have been previously used for detecting in vitro mutagenic effects and that urinary 1-hydroxypyrene levels of only 2.5 ng ml −1 may occur [17,10].…”

Wastewater Toxicity Assessment by Whole Cell Biosensor

“…ToxAlert 10 (Merck Ltd UK). Meanwhile the Microtox system has developed to include the Microtox chronic test [15] and the Mutatox genotoxicity test [16]. With the revolution in molecular biology and the ability to routinely manipulate the nucleic acids of bacteria, a major focus area is the development of genetically modified bacteria and other organisms for toxicity testing [17].…”

“…The choice between a natural hydrogel, such as agar or alginate, or a synthetic hydrogel, such as polyacrylamide, is dictated by a small number of key factors. Natural hydrogel materials are non-toxic to microorganisms, but are disadvantageous in a number of other aspects: -They have low mechanical strength -They require immobilisation of bacteria at around 45°C, which can be damaging to some cells -Most are rather biodegradable -They dry out quickly -Some (notably K-carrageenan and Ca-alginate) dissolve in media lacking the counterions necessary for their stabilisation, and thus dissolve in domestic wastewater [199] 204 J. Philp et al 16 Methods for immobilisation of biocatalysts by entrapment. From [197] Many or all of these limitations can be overcome by the use of a synthetic hydrogel, but many of these also have disadvantageous properties: they form gels at higher concentrations, which limits pore size and diffusivity [200], and the hydrogels themselves, or the polymerisation process, can be toxic to microorganisms.…”