The determination of chlorocarbons in drinking wateris described. The chlorocarbons studied include:tetrachloromethane, 1,1,1-trichloroethane, tribromomethane,bromodichloromethane, dibromochloromethane. Three methods ofsample preparation were compared: liquid-liquid extraction(LLE), purge & trap (P&T) and direct aqueous injection (DAI).The samples of drinking water were taken from Toruń (Poland):local sources, municipal water intake, drilled wells. Theobtained data allowed to create the map of chlorocarbonscontamination for Toruń town. Repeatability, linearity anddetection limits of LLE, P&T, DAI were evaluated forhalocarbons under investigation.

Using ¹³C/¹²C ratios in particulate organic carbon(POC), this study evaluated the fraction of terrestrially derivedPOC in Winyah Bay, South Carolina, an anthropogenically impactedestuary in the southeastern United States. Results from themixing model, which should be viewed as an upper limit becauseof possible dilution from additional potential end-members,showed that between 50 and 90% of POC in the Winyah Bay estuaryis of terrestrial origin. As this POC may be associated withriver-transported pollutants, the potential for accumulation ofpollutants in Winyah Bay is high because POC may become trappedin the estuary as part of either estuarine bottom sediments,circulation or food webs. Thus strategies for pollutionmonitoring and control in the estuary and its watershed arenecessary for the future management of Winyah Bay naturalresources.

Water and sediment quality in threetidal bayous located near Pensacola, Florida, wereassessed during 1993–1995. The primary objective wasto determine the environmental condition of therelatively small urban bayous by comparing thechemical quality of the sediments and surface waterwith published guidelines and criteria developed toprotect marine life. Surface water concentrations ofmost potential toxicants such as heavy metals,organochloride pesticides, PAHs and PCBs were usuallybelow method detection limits. The major exception tothis trend was for copper which consistently exceededFlorida and National acute and chronic water qualitycriteria. Nickel, cadmium and chromium intermittentlyexceeded these criteria. Sediment contamination wassite-specific and chemically diverse. Theconcentrations of as many as 17 compounds exceededproposed Florida sediment quality assessmentguidelines indicating the potential for adversebiological effects. Nutrient concentrations, with oneexception, were below average levels found in otherFlorida estuaries. Seasonal variation in contaminantconcentrations for sediment collected from the samesampling station was less than an order of magnitude. The differences in the concentrations of the sameanalytes as measured for the multiple samplingstations located within the same bayou varied 1 to 2orders of magnitude and over 2 orders of magnitude forthe 20 sampling stations located in the three bayous. A within-bayou sediment contaminant gradient wasevident; sediment quality generally improved seaward.

Some biological effects of soilfertilisation with sewage sludge were investigated aftersoil reclamation in an opencast mining area. Two earthwormspecies (Allolobophora chlorotica chloroticaand Nicodrilus caliginosus meridionalis) inhabitingthe reclaimed soil were tested for their response to twohigh doses of sludge (75 and 150 g kg⁻¹ of dry sludgein dry sieved soil). The metal concentrations in thesludge amended soils were below that which worm mortalitywould be expected. Mean annual density of the earthwormswas higher in the plots where the sludge was applied (435and 335 ind. m⁻²) than in control (115 ind. m⁻²).We verified the accumulation of Cd and Zn by the twoearthworm species at any dose of sludge, and metalaccumulation was higher in N. caliginosus than inA. chlorotica. Zn, Pb, Cr, Cu and Ni were moreconcentrated in the earthworm egesta than in the bulk soil.

The focus in the present study is the spatialvariation of anthropogenic volatile organic carbon compounds (VOC), mainly benzene and toluene, in parks and their built-up surroundings. Case studies were located in two large Scandinavian cities and measurements were made two meters aboveground level in maximum traffic periods. The results showedlarge variations in time and space but despite high pollutionlevels in the streets the air in parks and non-traffickedbuilt-up areas are substantially cleaner. The pollutantconcentration inside a large park decreased to a low level(i.e. 1/3 to 1/9 the concentration at the source) in a shortdistance (<40 m). An analysis showed that measured VOC wasassociated with fresh emissions, suggesting that the localtraffic intensity was the main governing parameter. It is,however, obvious that the spatial pattern of pollution is theresult of a combination of many different factors and variablesincluding traffic intensity, weather, local climate, land useand the character of park border.

Phosphorus and nitrogen can leach from porous golf greens potentially causing degradation of ground water quality. Agreenhouse experiment was carried out with 52 cm columns (15 cm diam.) made to USGA green specifications and sodded to `Tifdwarf' bermudagrass to determine the effects of fertilizer sources at various rates on P and N leaching. Fertilizers were balanced soluble and controlled-release (polyand sulfur coated) sources at N rates of 0, 12, 24, and 49 kg N ha⁻¹ and at P rates of 0, 5, 11, and 21 kg ha⁻¹ every other week for a total of 6 applications. Controlled-release N was from NH₄ and urea and the soluble source N was from KNO₃, urea, and (NH₄)PO₄. Irrigation rate was 0.63 cm per day initially and increased to 1.25 cm per day at week 7. Weeklyleachate collections for 23 weeks were analyzed for P andNO₃-N. Concentrations of N and P were lower in the leachatefor the controlled-release source than for the soluble source. Leaching of P continued for the entire 23 weeks of theexperiment, whereas N was essentially exhausted by week 15indicating that P leaches at a slower rate than N. For the low Prate (5 kg ha⁻¹) for the controlled-release source there was no increase in P concentration in the leachate compared to control. Thus, low P rates will not result in degradation of water quality due to increased P. For the controlled-release source at the low rate <10% of the P added leached, whereasthe values for N were in the range of 20 to 45% for all ratesand sources. Control treatments resulted in N concentrations in the leachate as high as 26 mg L⁻¹. Results show thatP leaching is a potential problem only at high rates of solublesources and high irrigation, whereas N is more readily leached.

A new technique based on traditional concepts has beendeveloped for rapid, on-site analysis of mercury inenvironmental media. In this method, mercury isanalyzed by integration of thermal decomposition,amalgamation, and atomic absorption spectrometry(TDA-AAS). Sample preparation and analysis areessentially integrated into a single instrumentalsystem; solid samples can be analyzed directly,without chemical pre-treatment, in an analysis time ofapproximately 5 minutes per sample. A wide range ofstandard reference material has been analyzed byTDA-AAS. Agreement with the certified values at the95% confidence interval for all matrices testedvalidates this technique. Subsequent to validation,TDA-AAS has been used in a series of field studies inconjunction with remediation of mercury-contaminatedsoil at natural gas utility sites. Reasonableagreement has been demonstrated between TDA-AASon-site results and laboratory results usingconventional mercury analysis techniques. Independentlaboratory confirmation of the field data is notrequired as TDA-AAS demonstrates lab-quality resultson-site. This field technique has been shown tosurpass traditional laboratory methods in terms ofboth precision and detection limits. A method for theUnited States Environmental Protection Agency (USEPA), Method 7473, has been developed and validatedbased on TDA-AAS methodology (US EPA, 1998).

The effect of soil treatment with brominal (a herbicide) and theinsecticide selecron (the equivalent field rates and five-fold) on population counts of bacteria, actinomycetes and celluloyticfungi in soil was tested throughout 10 weeks incubation at28 °C. Also, tested their effect on four soil enzymes:cellulase, acid phosphatase, alkaline phosphatase andarylsulphatase. Bacterial and actinomycetes populations in soiltreated with the two pesticides were promoted at fieldapplication rates and inhibited at higher levels. The twopesticides significantly decreased the total number ofcellulolytic fungi and most fungal species after most incubationperiods either by one or the two used levels but the effect ofselecron was more pronounced.Cellulase activity in soil treated with brominal and selecronwas inhibited after most incubation periods. The effect of soiltreatment with the two pesticides on acid phosphatase waspromotive at field application rates after some incubationperiods but the enzyme activity was delayed at the higherapplication doses. Alkaline phosphatase activity in treated soilwas accelerated with both pesticides even at the higherapplication rates, suggesting a direct role of alkaline soil pHin increasing resistance of alkaline phosphatase to pesticides.The effect of soil treatment with pesticides on arylsulphataseactivity fluctuated between promotion and inhibition, butinhibition was predominant.

Twelve Mediterranean hydrophyte species collected inLebanon were evaluated for their potential asbioindicator species for heavy metal pollution innutrient cultures enriched with 1 ppm Cr, Ni and Cd.These were: Nasturtium officinale R.Br, Apium nodiflorum L., Veronica beccabunga L., Veronica anagallis aquatica L., Veronicalysimachioides L., Veronica anagalloides L., Mentha longifolia L., Mentha aquatica L., Mentha pulegium L., Potentilla reptansL., Mentha sylvestris L., and Cardamine uliginosa L.. Large variability in responseto exposure to the heavy metals was observed. Growthrates remained high during the experimental period,indicating that the plants were little affected by thepresence of the metal at the experimentalconcentration. Metal accumulation and bioconcentrationvaried within at least one order of magnitude, andranged from less than 10 to over 200. Cr waspreferentially accumulated in the roots. All speciesbut M. pulegium, P. reptans and V. anagallisaquatica accumulated and bioconcentrated sufficientCr to qualify as bioindicator species. Five of thespecies that accumulated Cr also accumulated Ni, withthe same partitioning into the root. These were: N. officinale, C. uliginosa sp., M. longifolia, M. aquatica and M. sylvestris, all of which mayalso be used as bioindicators of Ni pollution. Onlyone species, M. aquatica, accumulated Cdsignificantly, and may, therefore, be used as abioindicator for all three metals.

The starch manufacturing industrial units, such as sago mills,both in medium and large scale, suffer from inadequate treatment and disposal problems due to high concentration of suspended solids present in the sludge. A laboratory scale study was conducted to investigate the viability of anaerobic treatment of sago waste sludge, enriched in particulate organicmatter, using a fluidized bed reactor. The start-up of the reactor was carried out using a mixture of digested supernatantsewage sludge and cow dung slurry in different proportions. The effect of operating variables such as COD of the effluent, bed expansion, minimum fluidization velocity on efficiency oftreatment and recovery of biogas was investigated. The maximum efficiency of treatment was found to be 82% and the nitrogen enriched digested sludge was recommended for agricultural use. A kinetic model was developed for the degradation of particulate organic matter using the general kinetic equation [dS/dt = K HC SXC] which allowed for a more accurate mathematical representation of the hydrolysis process. Analysing data from a series of batch tests, the best fit value of C was found to be in the range 0.43 to 0.62.