Measurement of the distribution of m-xylene in rat tissues by head space gas chromatography.

An automated head space-gas chromatography (HS-GC) method was developed and evaluated for reliability in measurement of m-xylene in rat tissues. For tissue samples spiked with m-xylene (n = 2), the analytical precision was better than 12% relatives standard deviation (RSD) over the concentration range of 0.1 to ca 100 micrograms/g for liver and kidney, 0.

Application of an automated HS-GC method in partition coefficient determination for xylenes and ethylbenzene in rat tissues.

An automated static head space-gas chromatography method was used in the determination of partition coefficients (Kd) for the xylene isomers and ethylbenzene in blood, brain, muscle, kidney, liver and fat of Sprague Dawley rats. Since homogenization resulted in the potential loss of analytes from tissue samples, unhomogenized samples were used. With a few exceptions, tissue:air Kd values were independent of the concentrations of the analytes, singly or as a mixture.

Sonication of aqueous solutions of chlorobenzene.

Sonication at two frequencies (20 and 900 kHz) was carried out on dilute (220 ppm) aqueous solutions of chlorobenzene. The formation of chloride ions was followed using ion chromatography. The solutions became more colored with time; the absorbance maximum was around 270 nm.

The effect of frequency on sonochemical reactions III: dissociation of carbon disulfide.

Investigations were made of the effects of frequency, temperature, intensity and gases on the rate of sonochemical dissociation of carbon disulfide. Application of 900 kHz ultrasound did not produce any noticeable change. When carbon disulfide was irradiated with 20 kHz, the liquid formed a heterogeneous mixture of black particles in a yellow solution.

Environmental health and monitoring in Estonia.

An assessment of environmental health and monitoring in Estonia after the dissolution of the Soviet Union has shown that the country suffered from neglect during the "cold war" after World War II, and efforts to improve the status quo have been slow since independence was gained in 1991. Conditions in Estonia are affected by the fifty-year long occupation. Industrial, military and agricultural activities have left a legacy of pollution and obsolete installations.

An automated head space analysis method for xylenes and ethylbenzene in blood and water.

A sensitive, reliable method of analysis was established for water and blood samples containing xylene isomers (m-,o- & p-) and ethylbenzene by means of an automated head space sampler connected to a GC equipped with a flame ionization detector. Minimum detection limits (MDLs) were ca. 1 and 6 ng/mL, respectively, for each of the four target compounds in water and blood samples.

Mutagenicity and chemical analysis of sequential organic extracts of airborne particulates.

To obtain insight into the identity of chemicals associated with the mutagenicity of United States National Institute of Standards and Technology (NIST) Standard Reference Materials SRM 1649 (urban dust) and SRM 1650 (diesel particulate), parallel mutagenicity tests and chemical analyses were performed on dichloromethane and sequential organic extracts of these samples. SRM 1649 and 1650 were sequentially extracted with five organic solvents of increasing polarity, in order to partition mutagenic components into discrete fractions. The solvents (with associated polarity index) were as follows: (1) hexane (0.

Short-term dermal toxicity and mutagenicity of coal coprocessing products in the rat.

The present study was conducted to determine the dermal toxicity of coal coprocessing products and to assess their potential health hazards. Groups of 10 male and 10 female Sprague-Dawley rats were administered dermally coal coprocessing products (light gas oil, LGO; heavy gas oil I, HGOI; heavy gas oil II, HGOII) at 1 g/kg body weight/d for 14 d. The control and positive control groups received normal saline and a coal liquefaction product (CLP) at the same dose level, respectively.

Subacute inhalation toxicity of a medium-boiling coal liquefaction product (154-378 degrees C) in the rat [Part III].

The short-term inhalation toxicity of a medium-boiling coal liquefaction product (CLP) was investigated in the rat. Groups of 5 male and 5 female Sprague-Dawley rats were exposed to CLP aerosols at 25 mg/m3 (low dose) or 100 mg/m3 (high dose) 6 h/d, 5 d/w, for 4 wk. The control group was exposed to filtered air while the positive control received diesel fuel aerosols at 100 mg/m3.

A review of techniques for measurement of airborne aldehydes.

The literature on aldehyde measurement methods was surveyed and critically reviewed to determine which methods would prove most suitable for monitoring personal exposure to a number of aldehyde compounds that have been found in air. A variety of methods was found that were applicable to measurement of specific aldehydes. Some of these were based on instrumental and spectrophotometric analytical methods.

Dermal toxicity of a medium-boiling (154-378 degrees C) coal liquefaction product in the rat--Part I.

The subchronic dermal toxicity of a medium-boiling coal liquefaction product (CLP, 154-378 degrees C) was investigated in the rat. CLP was applied to the shaved backs of rats at dose levels of 50, 100, 200, or 400 mg/kg body weight.d, 7 d/wk for a period of 13 wk.

Dermal toxicity of a high-boiling (bp 250-450 degrees C) coal liquefaction product in the rat--II.

Coal liquefaction products have been considered as an alternate source of energy to replace conventional crude oil. The present study was designed to investigate the dermal toxicity of a heavy fraction of coal liquefaction product (CLP, bp 250-450 degrees C) in the rat. Groups of 10 male and 10 female Sprague-Dawley rats (180-200 g) were treated dermally with CLP at dose levels of 100, 200, 400, or 800 mg/kg body weight.

Fabric protectors. Part II - Propane, 1,1,1-trichloroethane, and petroleum distillates levels in air after application of fabric protectors.

Propane, 1,1,1-trichloroethane, and petroleum distillates levels in air which were generated during the use of aerosol type fabric protectors were monitored by means of the NIOSH charcoal tube, a glass bulb grab sampling, and the GASBADGE passive device techniques. Although 1982 ACGIH TLV-STEL were readily exceeded in an unventilated test room, when fabric was sprayed with 450 g of fabric protector in an unconfined area within a home the generated vapors quickly dispersed and STEL and 8-hour TWA-TLV were not exceeded.

Fabric protectors. Part I - Evaluation of a grab sampling technique for determination of organic vapors.

A grab sampling technique utilizing evacuated glass sampling bulbs was evaluated and was found suitable for the simultaneous determination of propane, 1,1,1-trichloroethane, and petroleum distillates which would be generated into air during the use of fabric protectors.

Mutagenicity in a modified Salmonella assay of fabric-protecting products containing 1,1,1-trichloroethane.

Methyl chloroform (1,1,1-trichloroethane) was identified as a major component in two fabric-protector spray products. Mutagenic effects were determined at several dosage levels for the two products and some of the identified components. Levels of organics in the air of sealed desiccators, used as exposure chambers in modified Salmonella reversion assays, were measured by a gas chromatographic technique.

Mutagenicity of paint removers containing dichloromethane.

A volatile component of commercially available paint and varnish removers was mutagenic in strains of Salmonella typhimurium TA1535, TA100 and TA98. Levels of dichloromethane in exposure chambers were determined by gas chromatography and were related directly to mutational dose-effect curves observed for the products.