A series of chemical extraction procedures are used to obtain data on the partitioning of trace metals among the various geochemical phases of sediments. These components include intersititial water, solubility of solid minerals, ions on exchange sites, metal carbonates, easily reducible phases, organics and sulfides, iron oxides, and lithogenous (mineral residual) fractions. In general, a mass balance of less than 10% deviation can be obtained. Experimental results show very small fractions of trace metals to be in the form of interstital water or soluble ions. Trace metals in the exchangeable phase are almost negligible, and those in the mineral residual phases range from 2.5% Cd for one sediment to 98% Cu for another. The non-residual trace metals content is found to increase with decreasing sand content.
A method for the determination of neophytadiene in the total particulate matter of cigarette smoke was developed and applied to test its relationship to isoprene deliveries. Neophytadiene is suggested as a preferred measure of the contribution of terpenoids to experimental tobacco smoke carcinogenicity. Typical deliveries of neophytadiene are presented.
Click to increase image sizeClick to decrease image sizeKey Words: toxinpoisonred tidered waterdinoflagellateshellfish poison
A study of the Flat Creek Embayment of Lake Sidney Lanier near Gainesville, Georgia revealed three genera of algae, Chlorococcum, Fragillaria and Nostoc, to be prominent in this eutrophic region of the lake. The algae was grown in phosphate-rich media and subsequently labelled with P-32. All species incorporated luxury amounts of phosphorus as determined by the uptake of P-32. The results indicate that the P-32 uptake is proportional to the surface-per-volume ratio. The higher surface-per-volume ratio resulted in greater uptake of P-32.
Use of hydrophobic membrane filters is shown to effectively reduce the interfering moisture level in the detection of SO2 in air at the parts per billion range. Quadrol is used as a sensitive coating on piezoelectric crystal detectors in a flow system.
The behavior of several metal chelates [X(N)] of 1-14C-(ethylenedinitrilo) tetraacetic acid [EDTA] under irradiation from a wide spectrum Xenon arc lamp has been studied. In static tests at pH 4.5, chelates of Mn(II), Fe(II) and Co(II) photodegraded to give 14CO2 and CH2O. Chelates of Na(I), Mg(II), Ca(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) did not exhibit any significant photodegradation as measured by 14CO2 evolution. It is concluded that the photodegradation of Fe(III)-EDTA by sunlight will prevent EDTA build up in natural waters.
Aluminum, barium, berylliu, bismuth, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, silver, strontium, vanadium and zinc concentrations in the sewage, effluents and sludges of ten southern Ontario wastewater treatment plants are reported. The efficiency for metal removal by a conventional activated sludge plant was determined. The effect of metal concentrations in receiving waters from residual metals in sewage effluents is discussed. The environmental hazards of disposing of sewage sludges with high metal content on agricultural land is considered.
The field observation that the occurrence of red tides at Omura Bay may have a close connection with the development of anoxic conditions in bottom waters was tested by bioassays of seawater collected during summer 1971. The stimulating effect of anaerobically-decomposed products of bottom mud on the growth of Gymnodinium type-'65 was examined. The results suggest that the development of oxygen deficiency in the bottom waters of Omura Bay makes the environment favourable for the growth of red tide organisms, both by the supply of inorganic nutrients and of some unidentified stimulants.
Adsorption of tryptophan onto CaCO3 at constant ionic strength (0.05 M Nacl) and from dilute aqueous solution (10(-4) M to 10(-3) M tryptophan) is reported. Adsorption was primarily determined by the charge characteristics of both the adsorbate amino acid and adsorbent CaCO3. When both adsorbate and adsorbent are semicharged, tryptophan ions are expelled away from the CaCO3-solution interface. Tryptophan is only removed by CaCO3 in a narrow pH range, 6.0 greater than pH less than 8.5 within which CaCO3 has positive charges, and tryptophan is negatively charged. The pH of zero point of charge, pHzpc, of CaCO3 was also determined by alkalimetric tritration and coagulation techniques and a value of 9.50 +/- 0.5 was found. These preliminary finding demonstrate primarily that interfacial chemical reactions play an important role in the temporal and spatial transformation of dissolved organic matter in natural water systems.
Vertical migration as an accumulation mechanism in the formation of red tide models is discussed with reference to extant mathematical models. Its relationship to other biological and physical factors such as population density changes, tidal rhythms, nutrient limitation and light intensity is evaluated in terms of its possible causal role in red tides.
Chloroform, bromodichloromethane, dibromochloromethane, bromoform, and dichloroiodomethane have been found in chlorinated drinking water. In addition to these five compounds, the other possible trihalomethanes (chlorodiiodomethane, bromochloroiodomethane, dibromoiodomethane, bromodiiodomethane, and iodoform) can also be formed by chlorination of surface water containing bromides and iodides. Mass spectra for each of these ten compounds were obtained.
The toxin from the dinoflagellate Gonyaulax tamarensis blocks nervous conduction through a selective inhibition of the mechanism whereby the membrane undergoes an increase in permeability to sodium ions. The effect is exerted only from outside of the nerve membrane. These effects are exactly the same as those exerted by tetrodotoxin or saxitoxin.
Assessment of the effects on land use, social, economic, historic and natural environment as a result of highway construction are discussed. Predictions of these effects on the various categories twenty years hence are also presented. Information of this type is a necessary segment of an environment impact study soas to conform to EPAand Department of Rransportation (DOT) guidelines.
The control of insect populations by restricting their birth rate offers several advantages over methods based on increasing the death rate. The sterile-male technique scored practical success in the control of the screwworm, Cochliomyia hominivorax (Coquerel), but more general applications of the sterility procedure may be expected in conjunction with the development of integrated procedures for pest insect management.
The distribution of O2, chlorophyll a, alkalinity, phosphate, Ca, Mg, Mn, Fe, Cu, Zn, Cd and Pb has been measured in the discharge plume of the large sewage treatment plant on Back River, Maryland. The concentrations of phosphate and the trace metals decrease downstream more rapidly than can be accounted for by conservative dilution. Solubility calculations suggest that saturation with respect to phosphate or oxyhydroxide phases could limit the mobility of phosphate, Fe, Mn, and Pb. For Cu, Zn, and Cd, saturation is not a feasible control mechanism, and other processes such as biofixation or adsorption are probably involved.
A comparison of the field attractiveness of five samples of American-synthesized and one sample of Japanese-synthesized (Z,E)-9,11-tetradecadien-1-01 acetate (9,11-TDDA), the sex pheromone of Spodoptera littoralis Boisd. and S. litura (F.), showed that traps baited with one of the American-produced samples and the Japanese product were equally effective in attracting and capturing S. littoralis males in cotton and alfalfa fields of Israel. Optimum captures were obtained for periods up to three months with 4800 mug of 9,11-TDDA plus 8 mg of an antioxidant; higher doses were not advantageous. Paper squares were superior to two types of rubber septa and to closed polyethylene vials as dispensers for the pheromone; the polyethylene vials were least effective. In terms of numbers of moths captured, open polyethylene vials were as effective as paper dispensers when both were baited with 9-11-TDDA plus antioxidant. Admixture of (Z,E)-9,12-tetradecadien-1-o1 acetate (9,12-TDDA) with 9,11-TDDA was antagonistic at ratios of 1:20 and 1:50, but ratios from 1:500 to 1:1600 were synergistic, increasing moth catches up to 2.5-fold. Pheromone traps placed in Caesarea sand dunes located at least 3 km from the nearest host area captured larger numbers of males than traps placed in cultivated areas. It is therefore recommended that safety belts of pheromone traps, about 500 m apart, be used around cultivated areas to prevent invasion of the pest from outside and to attract males present inside such areas, thus reducing both the male population and mating through mass trapping and disruption of sex communication.
A nine month study of current noise levels was made at twenty-two sites within a community in Eastern Pennsylvania to evaluate the noise pollution factors for a proposed highway. An attempt was made to correlateamnient noise levels for each day of theweek with each location. Computer programs were utilized for datareduction, statistical calculations, and prediction of future noise levels. The prediction analyses were composed of contour analyses, sensitive receptor sites analyses, and the "Do Nothing" analysis. Results indicated no noise pollution problems existed during the survey, but future noise levels may exceed Federal Standards for certain sections of the proposed alignments. Factors that cause the unacceptable future noise levels are identified and modifications may be incorporated for adherence to the standards.
Muskelung (Esox-masquinongy chiensis) fry were used in a 96 hour toxicity study with diquat and simazine. Although the death of sufficient control fish invalidated the test as a whole, some interesting observations were made. At the end of 48 hours 4 out of 10 fish had died in the control tank and 8 had died in the simazine tank while all 10 diquat-treated fish appeared healthy. Two model eco-systems with components from Chautauqua Lake, N.Y. were constructed in 20 gallon glass aquaria to trace the movement of 14C labeled diquat. After activity had reached near background levels in the water from the test tank, fish, plants, sediments and snails were counted in a liquid scintillation counter to discover the fate of diquat within the system. The concentration of diquat was found to be highest in sediments, followed by fish tissue, snail parts, with plants having the lowest measured concentration.
Chemicals which interfere with the growth and development of insects (morphogenetic agents) have been receiving major attention as potential means of selective insect control. Major advances in this field resulted from the identification of Juvenile Hormones -1, -2, and -3, and the discovery that various terpenoid and sesquiterpenoid derivatives were more potent morphogenetic agents than the three known Juvenile Hormones. Several highly active compounds have emerged from these research programs. Their field performance, problems, and prospects in selective insect control are considered here.
