There is neither a prescribed format nor a rigid sequence of testing to follow for the assessment of health and environmental effects of chemicals. Conventional animal toxicity tests plus medical surveillance and monitoring of exposed human populations will provide knowledge of the biological effects of chemicals and assurance that they can be handled safely. Useful information also can be deri...

Chemicals that specifically inhibit human neurite outgrowth pose a hazard to the developing nervous system. Identifying such chemicals remains a major challenge in biological research. In response to the need for more efficient methods to identify potential developmental neurotoxicants, an image processing framework is presented that allows to automatically quantify neurite growth in LUHMES hum...

1. A method is described for the primary growth of chick embryo liver cells on cover slips in culture, and the factors of the culture medium are considered that affect the induction of porphyrin formation with certain chemicals. 2. A method is described for following &aminolevulinic acid synthetase (ALA synthetase) activity by the determination of porphyrin fluorescence developed in the cells o...

polybrominated diphenyl ethers as flame retardants prevent the branching mechanism of free radicals in gas phase during the combustion. therefore, they are used in electric and electronical instruments. these supplies are entering the landfills after use. the existing flame retardants in these landfills enter the air, water and soil and pollute them. in this paper a mass-transfer model is devel...

In vitro liver preparations are increasingly used for the study of hepatotoxicity of chemicals. In recent years their actual advantages and limitations have been better defined. The cell models, slices, and mainly primary hepatocyte cultures, appear to be the most powerful in vitro systems, as liver-specific functions and responsiveness to inducers are retained either for a few days or several ...

Biological monitoring and biomarkers are used in occupational toxicology for a more accurate risk assessment of occupationally exposed people. Appropriate and validated biomarkers of internal dose, like urinary metabolites, besides to be positively correlated with external exposure, have a predictive value to the risk of adverse effects. The application of liquid chromatography-mass spectrometr...

Under the new European chemicals regulation, REACH, a new safety value, the Derived No Effect Level (DNEL) must be established for all chemicals manufactured, imported or used in the EU in quantities greater than 10 metric tonnes per year. The DNEL is to be calculated for all relevant exposure pathways, exposure populations, and endpoints of toxicity. The EU has published guidance on how to der...

High-performance liquid chromatography/mass spectrometry (HPLC/MS) is sensitive and specific for targeted quantitative analysis and is readily utilized for small molecules from biological matrices. This brief review describes recent selected HPLC/MS methods for the determination of urinary mercapturic acids (mercapturates) which are useful as biomarkers in characterizing human exposure to elect...