BAP Content Research Articles

Benzo[ a]pyrene in coal tar pitch: chemical conversion in situ by alkylation

Coal tar pitch was compounded with polyester resin or polyethylene glycols of different molecular masses. The group compositions of the pitch and the products were determined, as well as elemental analyses, free radical concentrations, infrared spectra and 13C n.m.r. spectra to elucidate structural changes and substitution of BaP. Over 90% reduction in BaP content was achieved, the mechanism probably including O-alkylation, and the products would be suitable for technical uses.

Bioavailable phosphorus dynamics in agricultural soils and effects on water quality

The transport of bioavailable phosphorus (BAP, i.e., algal available) in agricultural runoff can accelerate freshwater eutrophication. As procedural and theoretical limitations have restricted BAP estimation in agricultural soils and runoff, a routine method was developed using iron oxide-impregnated paper strips (Fe-oxide strips) as a sink for BAR Fe-oxide strips were used to investigate the amounts and seasonal dynamics of BAP in 12 Oklahoma soils over 2 years and the effect of agricultural management on BAP loss in runoff from these 12 and 8 additional sites over 4 years. The sites involved native grass, wheat ( Triticum aestivum L.), sorghum [ Sorghum bicolor (L.) Moench.], and peanut ( Arachis hypogaea L.). The strip P content of unfertilized soils was higher in winter (October–March; 10–19 mg kg −1) than spring months (May–June; 3–6 mg kg −1). For the P-fertilized soils, the strip P content increased from 8–17 mg kg −1 prior to P application (20–25 kg ha −1 yr −1 to 33–42 mg kg −1 immediately following application. Seasonal dynamics of strip and organic (OP) and inorganic P (IP) fractions indicated mineralization of moderately labile OP, as a function of phosphatase enzyme activity, and release of moderately labile IP and fertilizer P, as a function of P sorption capacity; these are the major processes controlling the strip P content of unfertilized and fertilized soil, respectively. Dissolved organic P did not reduce the efficiency of IP sorption by the Fe-oxide strips and removal of P from the strips by NaOH rather than H 2S0 4 minimized hydrolysis of OP sorbed on the strip. The loss of BAP in runoff was a function of watershed management. Over the 4-yr study, BAP losses increased in the order reduced till (98 g ha −1 yr −1), native grass (160 g ha −1 yr −1), no till (382 g ha −1 yr −1), and conventional till (678 g ha −1 yr −1). Although the total P loss was 93% lower from no till than conventional till, 73% was bioavailable for no till compared to only 28% for conventional till. Clearly, strip P is a dynamic soil property, which, along with watershed management, can influence the bioavailability of P loss in runoff. Thus, the BAP content of runoff in conjunction with runoff and erosion potential may provide a more reliable index of the trophic response of receiving water bodies than dissolved or total P.

Bioavailability of organic pollutants in boreal waters with varying levels of dissolved organic material

Dissolved organic matter (DOM) in 20 surface waters in Eastern Finland were characterized to examine relationships between structural and compositional properties of DOM and partition coefficients ( K p) describing sorption of four model contaminants to DOM and the bioavailability of contaminants by Daphnia magna. The hydrophobic acids (HbA), hydrophobic neutrals (HbN) and hydrophilic (HI) fractions of DOM were separated by XAD-8 resin. The K Ps were measured by equilibrium dialysis. Model contaminants were benzo(a)pyrene (BaP), naphthalene (NAPH), 3.3′,4.4′-tetrachlorobiphenyl (TCB) and dehydroabietic acid (DHAA). DOM concentrations varied from 2.0 to 38.3 mg org. C/l in the water series. The percentage of HbA and the aromaticity of DOM, as indicated by the absorptivity at 270 nm (A 270) and hydrogen/carbon ratio (H/C ratio), increased with increasing DOM concentration. Significant correlations were observed between K P of BAP, A 270 and HbA content of the DOM from different sources. For the other contaminants similar kinds of relationships between K p s and quality parameters of DOM could not be found. The bioavailability of model compounds was decreased by increasing DOM concentration in the water series. For all four model contaminants, measured bioconcentration factors (BCF) correlated well with the A 270 of a water and HbA content of the DOM. These results show that the total DOM concentration is an important factor controlling the bioavailability of xenobiotics in natural waters. Besides the quantity also the quality of DOM, like proportion of HbA, can contribute in bioavailability.

Investigations of Indoor and Outdoor Levels of Benzo(a) Pyrene in a Community of Older Homes

Abstract Indoor and outdoor air measurements of PM-10 (particulate mass dp < 10 μm) and its benzo (a)pyrene (Bap) content were made daily in 13 residences and 5 nearby sites during one or more of three 14-day periods (Winters 1987 and 1988, and Fall 1988). These are a population of older homes (60+ years) adjacent to a gray-iron foundry. Winter BaP values were ∼ 10 × higher than fall values. Indoor BaP sources in several homes (e.g., cooking, cigarette smoke, a coal stove) led to contaminant levels higher than the ambient concentrations. However, in homes without strong sources, concentrations were very close to outdoor levels. Periods of elevated ambient pollution were readily discernible in the record of virtually all homes. Correlations for indoor-outdoor concentrations (PM-10 and BaP) were statistically significant (p < 0.01) in the majority of homes. Higher BaP concentrations were associated with periods of lower temperatures. There were high degrees of correlation for BaP and PM-10 among outdoor sit...

Somatic Embryogenesis in Aesculus hippocastanum L. by Culture of Filament Callus

Filaments were harvested from 10–100 year old trees and were cultivated on modified WPM-Media with different BAP- and 2,4-D-contents. The filaments placed on a medium with 2.5 μ mol/l BAP and 5.0 μ mol/12,4-D developed to callus. After transferring this callus to the same medium without 2,4-D, development of embryos from this callus could be observed. In some cases the whole callus was transformed to embryos when the BAP content was lowered to 0.75 μ mol/1.

Large-scalein-vitropropagation ofSenecio×hybridusHyl.

SummaryA method for large-scale micropropagation from mature plants of Senecio × hybridus is described. Adventitious shoots were initiated on petiole expiants and then excised and subcultured to obtain multiple shoot formation. The macronutrients of Murashige and Skoog (1962) were used. High IAA concentrations (4–8 mgl−1) combined with 1 mgl−1 BAP were most useful for shoot initiation on petioles. The IAA content had to be lowered (0–0.1 mgl−1) when the shoots were subcultured to avoid inhibition of shoot production. The BAP content was varied between 0.1 and 1 mg l−1 to achieve a balance between the size and number of shoots formed. When no BAP or only a little (0.1 mg 1−1) was used in the subculture before transfer to soil, no other treatments were needed to establish root formation. Plants were stored in vitro for 6 months at 10°C in 400 lux without transfer to fresh medium. Some of the plants produced had more than one shoot and all the plants developed and flowered in a normal way.

Lung tumours in rats and mice after inhalation of PAH-rich emissions

Rats and mice were exposed to a PAH-rich emission to test the carcinogenic activity. The BaP content of the exposure atmosphere was only 2-3 times higher than the concentration of about 30 micrograms/m3 measured in older coke plants. Although only half of the rats exposed to the exhaust have been investigated histologically up to now, the lung cancer incidence already amounts to 11%, no lung tumours were found in the control animals. Also the mice exposed to the exhaust with and without additional treatment with BaP, DBahA or urethane to induce a "base tumour rate" in the lung, showed a clear exhaust exposure-related carcinogenic effect. The lung tumour multiplicity as well as the incidence was significantly higher. The epidemiological findings of an increased lung cancer risk in coke oven workers can now be supported by the results of this animal inhalation study.

Background environmental pollution of the Eurasian continent

(1) The interest to studying pollution of environmental media on the background level has grown in the recent years. There arose a necessity to establish a specialized observational system for conducting observations of changes in the state of the environment, and of ecological consequences of pollution as well as to produce assessments of the current and predicted states. The realized program of background monitoring and first results of integrated background measurements have already been published. The paper presented illustrates time-and-space features of the background pollution of natural environmental media according to data from various background stations. (2) Long-term systematic measurements at the 'Borovoe' station (Kazakh SSR) commenced in 1976 have been supplemented with the results of the background pollution studies carried out in Berezinskyi, Caucasian, Central-Chernozem, Sary-Chelek, and Repetek Biosphere Reserves and in locations of the background stations in Hungary and Czechoslovakia. The data from the Hungarian and Czechoslovak stations were obtained during joint expeditions. Details are given in the relevant publications. (3) Ozone. Ozone measurements show the diurnal variation with the day-time maxima from 35 up to 160 μg m(-3). The correlation between day-time and nocturnal concentrations is a good indicator of the anthropogenic effect. (4) Sulphur dioxide and sulphates. The annual variation of sulphur dioxide characterised by winter maximum and summer minimum indicates the direct dependence on the amount of fuel burnt in the given region. Mean values of the sulphur dioxide content in the surface layer of the atmosphere correlates with the extent of the region urbanization and varies within 0.2-12.5 μg m(-3). The value of sulphur dioxide and sulphates correlation in the atmosphere is rather stable and varies within 0.18-0.37 μg m(-3). (5) Heavy metals. The annual cycle of the atmospheric content of lead, cadmium and arsenic is well expressed by winter maximum and summer minimum (which is opposite in case of mercury). As for lead and mercury, their annual variation is more distinct than that of cadmium and arsenic; their time-and-space variation is also more distinct. The content of these metals in the urbanized regions of Europe is 5 times higher than in Asia and the Caucasus. Atmospheric contents of arsenic and cadmium vary insignificantly from region to region. The content of all these metals in other environmental media (soil, water, vegetation) is of insignificant spatial variability. Observations in the Caucasian Biosphere Reserve showed minimum levels of the background atmospheric pollution: lead-16 μg m(-3), mercury-5 ng m(-3), arsenic-3.9 ng m(-3), cadmium-0.5 ng m(-3). (6) Organochloride pesticides. Concentrations of DDT and its metabolites and hexachlorocyclohexane isomers in the environmental media of European background regions are 3 times higher than those in Asia ('Borovoe'). (7) PAH. Atmospheric content of BaP has a well expressed annual variation with winter maximum; the difference between winter and summer periods reaches the magnitude of an order. Background concentrations in European regions (Hungary, Berzinskyi Biosphere Reserve) are noticeably higher than in Asia; the difference reaches 3-5 times. (8) Comparisons with literature data on the background pollution show that observational materials from the background monitoring stations supplement to a considerable extent, and extent, the current notions on the background pollution and show the effects of the man-made impact on the background regions.