This aim of study was to compare the performance of a biofilter (BF) and trickle bed reactor (TBR) under increased styrene loading with a constant acetone load, 2 gc/m /h. At styrene loading rates up to 30 gc/m /h, the BF showed higher styrene removal than TBR. However, the BF efficiency started to drop beyond this threshold loading and could never reach steady state, whereas the TBR continued ...

This study examined biodegradation kinetics of styrene and ethylbenzene as representatives of alkenylbenzenes and mono-alkylbenzenes, respectively. The compounds were studied independently and as binary mixtures using a series of aerobic batch degradation experiments introduced by acclimatized mix culture. Initial concentration of styrene and ethylbenzene in the liquid phase vacillated from 0 t...

Metabolic activation is considered to be a critical step for styrene-induced pulmonary toxicity. Styrene-7,8-oxide is a primary oxidative metabolite generated by vinyl epoxidation of styrene. In addition, urinary 4-vinylphenol (4-VP), a phenolic metabolite formed by aromatic hydroxylation, has been detected in workers and experimental animals after exposure to styrene. In the present study, new...

Bottled water may not be safer, or healthier, than tap water. The present studies have proved that styrene and some other aromatic compounds leach continuously from polystyrene (PS) bottles used locally for packaging. Water sapmles in contact with PS were extracted by a preconcentration technique called as "purge and trap" and analysed by gas chromatograph-mass spectrometer (GC/MS). Eleven arom...

Two different mechanisms were responsible for the disappearance of styrene in enrichment cultures: (i) a mixed population of microorganisms, capable of utilizing styrene as a sole carbon source, oxidized this substrate to phenylethanol and phenylacetic acid; (ii) the culture also mediated polymerization of the monomer to low-molecular-weight styrene oligomers. This chemical reaction probably oc...

Styrene-specific N-7- and O6-guanine DNA adducts and N-terminal valine adducts were determined in mice tissues after the intraperitoneal administration of styrene. Blood, liver, lungs and spleen were collected 3 h after administration of various doses (from 0 to 4.35 mmol/kg b.w.) of styrene. DNA adducts were analysed by the modified 32P-postlabelling assay and N-terminal valine adducts were de...

Styrene is a commercially important chemical widely used in the manufacture of synthetic rubber, resins, polyesters and plastics. The highest levels of human exposure to styrene occur during the production of reinforced plastic products. The objective of this work was to evaluate both DNA and cytogenetic damage in styrene-exposed workers, analysing only non-smoker individuals. Environmental lev...

Styrene is discharged particulary from the factories of styrene resin and synthetic rubber, and it was listed as one of the offensive odor substances by the Offensive Odor Control Law in Japan at 1976. Styrene vapor has stimulating action on eye (STEWART et al. 1968) and membrana of nose and trachea (STEPHENSON & FOSDICK 1960). It has toxic effects on blood cells and liver (KATZ 1962), and nerv...

To elucidate the effect of maternal styrene exposure, which is due to various postnatal changes in the development and behavior of offspring, we investigated pregnancy-induced changes in the metabolism of styrene in rat liver in relation to the regulation of cytochrome P450 enzymes. We also examined age and sex-induced changes in the metabolism of styrene. Pregnancy appeared to exert a negative...

An effort was made to improve the separation issue of styrene-butadiene-styrene modifiers in styrene-butadiene-styrene-modified asphalt binders and further enhance their performance by adding nano-ZnO binder prepare compound modified binder. First, optimum dosage determined based on conventional tests, i.e., penetration, ring ball softening point, ductility at a fixed dosage; then, dynamic shea...