DDT in fish from the Bulgarian region of the Black Sea

In spite of a worldwide reduction in the utilization of organochlorine pesticides (OCPs), they are still a problem for the aquatic environment and human health. The Black Sea is still being polluted with persistent chemicals, including OCPs. Aquatic organisms (sprat, scad, bluefish, shad, belted bonito, goby, and black mussel) with different feeding behaviours were sampled on a seasonal basis from the Bulgarian region of the Black Sea, and the concentrations of 13 OCP residues were determined. Although many of the OCPs were not detected in the samples, in all samples 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) was present mainly in the form of its metabolites 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE). Only about 12% of the total DDT was present as the parent compound pp-DDT, which suggests that it was not being used recently in the region. The total DDT concentrations were generally below 150 μg kg^-1 fresh weight, but higher levels—up to 354 μg kg^-1 fresh weight—were also measured for fish species with a high fat content. Between-species differences were observed, even when the concentrations were presented on a fat-level basis. DDT concentrations did not show any significant changes over the 2-yr sampling period. Fish sampled in the northern areas of the Bulgarian Black Sea coast seemed to contain higher DDT levels than those from the southern areas, suggesting a major (historical) influence of the Danube River. For permanent monitoring purposes, the utility of Black Sea gobies and scad should be considered.     

Design and validation of a practical index for trauma assessment

In the past 20 years a variety of indices have been suggested for measuring the severity of trauma, however none of them meets the requirement of being a simple and objective instrument that can be utilized efficiently by lay persons and providers of health services without previous experience in triaging. A new system has been proposed which meets this requirement and which has been validated with 197 injured persons at the emergency ward of the Valle University Hospital in Call, Colombia. The instrument showed a high level of concordance with the conventional triaging method and classifies victims into four categories: critical with recovery unlikely, critical but recoverable, moderately serious, and ambulatory. There is discussion on the reliability of this instrument and it is recommended that it be validated with victims from larger disasters. Regardless, it has the advantage of being specific and free of the subjectivity that characterizes other indices.     

Characteristic features of body composition and metabolism in some interzonal copepods

Protein, lipid, phosphorus, and organic carbon contents, as well as electron transport system (ETS) activity, lactatedehydrogenase activity, and gut evacuation rate, were measured in four interzonal species of Pacific copepods:Calanus australis, C. pacificus, Eucalanus inermis, andE. elongatus f.hyalinus, collected at the upwelling areas off Peru (8°S) and California (27°N), and in the middle of the North Pacific (30°N), from February to April 1987. The two Eucalanidae species —E. inermis andE. elongatus — have distinctive biochemical and elemental body composition and rates of main physiological processes. Relative protein, lipid, phosphorus, and organic carbon contents (µg mg^–1 wet weight) in these species were, respectively, ca. 1/7 to 1/10, 1/5 to 1/20, 1/5 to 1/10, and 1/5 those inCalanus spp. Likewise, oxygen uptake rate per unit of wet weight (based on ETS activity) inE. inermis andE. elongatus was 5 to 10% of that in calanids; a similar difference was found in phosphorus excretion rate. In addition, gut evacuation rates inE. inermis andE. elongatus were ca. one-fifth of those inCalanus spp. Based on these data, we considered the eucalanids as belonging to a distinctive physiological group, figuratively named jelly-body copepods. In contrast with calanids, active lactatedehydrogenase has been found in the bodies ofE. inermis andE. elongatus, apparently allowing them to survive for a long time in layers of extremely low oxygen content (<0.2 ml l^–1). The adaptive value of physiological features in these eucalanids and typical calanids is compared.     

Dominions and desert clickers (Orthoptera:Acrididae): influences of resources and male signaling on female settlement patterns

Summary Previous field work on the grasshopper Ligurotettix coquilletti revealed that females were not evenly distributed among male mating territories, Larrea tridentata (creosote) bushes, but were clustered at particular locations. These sites generally harbored several signaling males simultaneously and also possessed foliage preferred by the insects as a food source, this preference being based on the relative concentrations of various extra-foliar compounds. The clustering of females, therefore, could result from a preference for specific bushes because of the resources (i.e., food) available there and/or an orientation to groups of males per se. Here, we present the results of 3 field experiments in which we controlled the spatial distribution and intensity of male signals using a computer-operated system of loudspeakers and monitored the movement of individually marked females released in the study area. When male song was identical at high and low quality territories (all having single loudspeakers), females still aggregated at the high quality sites, indicating that variability in host plant quality alone may be sufficient to promote a skewed distribution of females. Among high quality territories, females did not discriminate between sites with one versus three loudspeakers (all broadcasting the same signal), but displayed a strong preference for sites (all having single loudspeakers) with a high intensity signal over a low intensity one. Field measurements showed that the songs of grouped males were more intense than those of lone males, implying that the signaling of grouped males may have enhanced the settlement of females at the bushes harboring male groups above and beyond that influenced by territory quality alone. We conclude that female attraction to host plants is influenced primarily by male signaling, whereas their subsequent retention is more dependent on territory quality. An experiment on male settlement failed to show an aggregative tendency, suggesting that male groups form through the passive accumulation of individuals at high quality sites.     

Sulfate and conductivity as field indicators for detecting coal-mining pollution

A water quality assessment was conducted on three Appalachian streams polluted by coal mining at the Big South Fork National River and Recreation Area, Tennessee and Kentucky. Results showed that sulfate was an excellent parameter for detecting the effects of coal mining and that sulfate analyses used in conjunction with conductivity readings provided the best detection index. Acidity and pH readings were relatively insensitive indicators, reflecting the mining pollution only after sulfate concentrations already indicated severe pollution levels.Hydrologist, Big South Fork NRRA, during the study; presently at Cape Lookout National SeashoreHydrologist, NPS, during the study; presently with USDA-Forest Service, Washington, DC.     

The extraction of aged polycyclic aromatic hydrocarbon (PAH) residues from a clay soil using sonication and a Soxhlet procedure: a comparative study

A sonication method was compared with Soxhlet extraction for recovering polycyclic aromatic hydrocarbons (PAH) from a clay soil that had been contaminated with tar materials for several decades. Using sonication over an 8 h extraction period, maximum extraction of the 16 US EPA priority PAH was obtained with dichloromethane (DCM)-acetone (1 + 1). The same procedure using hexane-acetone (1 + 1) recovered 86% of that obtained using DCM-acetone (1 + 1). PAH recovery was dependent on time of extraction up to a period of 8 h. The sonication procedure showed that individual PAH are extracted at differing rates depending on the number of fused rings in the molecule. Soxhlet extraction [with DCM-acetone (1 + 1)] over an 8 h period recovered 95% of the PAH removed by the sonication procedure using DCM-acetone (1 + 1), indicating that rigorous sonication can achieve PAH recoveries similar to those obtained by Soxhlet extraction. The lower recovery with the Soxhlet extraction was explained by the observed losses of the volatile PAH components after 1-4 h of extraction. The type of solvent used, the length of time of extraction and extraction method influenced the quantification of PAH in the soil. Therefore, the study has implications for PAH analyses in soils and sediments, and particularly for contaminated site assessments where the data from commercial laboratories are being used. The study emphasizes the importance of establishing (and being consistent in the application of) a vigorous extraction, particularly for commercial laboratories that handle samples of soil in batches (at different times) from a single site investigation or remediation process. The strong binding of PAH to soil, forming aged residues, has significant implications for extraction efficiency. This paper illustrates the problem of the underestimation of PAH using the US EPA method 3550, specifically where a surrogate spike is routinely employed and the efficiency of the extraction procedure for aged residues is unknown. The implications of this study for environmental monitoring, particularly where numerous batches of samples from a single site assessment or remediation program are submitted to commercial laboratories, is that it would be advisable for these laboratories to check their existing method's extraction efficiencies by conducting a time course sonication extraction on their particular soil to determine the optimum extraction time.     

Problems of correlation of global and local monitoring of air pollution

1. The Air Polluttion Monitoring System has got a significant development of late, which is in direct relation with a considerable extention and improvement of the observation network in cities and industrial areas, with creation of a new network for assessing regional and global background of the atmosphere pollution, as well as with the wide involvement of meteorologists to monitoring organization.
2. While developing a new global monitoring system, it is necessary to take into account its relationship with the local monitoring within the region of air pollution sources, i.e. at the \lsimpact\rs level. The need in such an account is dictated first of all by the physics of pollutant spreading that states: changes in air pollution over large territories must be in a certain agreement with greater changes in the vicinity of emission sources. Methods applied in the global and local monitoring have also a number of common peculiarities. White organizing regional network for observations of the background pollution of the atmosphere twin stations (one of the pair of stations located outside the city boundaries in a small community, and the other, in the nearest city with the population of 200–400 thousand inhabitants) were established in the U.S.S.R. and in a number of socialist countries in Europe.
3. Implementation of the twin-station principles in the U.S.S.R. has contributed to data interpretation and representativity assessment as well as to correction of the station location. Observation results from the Soviet background stations and those abroad have been compared by now according to a number of indices.
4. The correlation of monitoring systems of various scales tells positively both on mutual improvement and completion of observational methods. The methods of obtaining integral characteristics of air pollution were used for the global monitoring, in particular spectral actinometric observations and chemical analysis of the precipitation composition. Now they find still wider employment. Thus methods of spectral actinometric measurements and data processing were used to estimate the degree of aerosol pollution of a number of industrial centres. The theory of solar radiation spreading and aerosol contents determination in urban atmosphere has also been developed. It is a generalization of an earlier developed theory, used to estimate global atmosphere pollution basing on actinometric data. The organization of precipitation collection and analysis on a network of stations around Leningrad and in Donbass area enables us to compare the admixture content in precipitations falling in industrial and agricultural areas.
5. A considerable increase of possibilities to measure microconcentrations of sulphur dioxide, nitrogen oxides and of a number of other pollutants is connected with the use of solid solvents for sampling. Their use will allow to avoid establishment of special laboratories at background stations and only send samples by post for their analysis in centralized laboratories.

They will also allow to considerably increase precision and accuracy of measurements. The international comparisons of methods of air pollution measurements on the background level allow to judge about the effiency of these methods.