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.