The effect of cadmium ion on the growth,photosynthesis, and nitrogenase activity of Anabaenainaequalis

The growth of $\text{Anabaena}$$\text{inaequalis}$ was significantly inhibited by Cd²⁺ concentrations greater than 0.02 ppm (μg/ml) and completely inhibited at 0.06 ppm (Day 12). Cadmium had no significant effect upon the lag phase of growth or the culture doubling time, but caused the retardation phase to arrive sooner. One ppm Cd²⁺ significantly inhibited the rates of both photosynthesis and acetylene reduction, by $\text{A}$. $\text{inaequalis}$, with complete inhibition at 4 and 20 ppm respectively. Cell sensitivity increased directly with exposure time. Cadmium caused some cell lysis of $\text{A}$. $\text{inaequalis}$ and induced an increase in filament length, heterocyst frequency, and a loss of cellular contents from filament apical cells. The cellular abnormalities observed and the fact that toxicity increased with longer exposure times, suggested that metal toxicity resulted from effects of Cd²⁺ taken up by cells rather than Cd²⁺ at the cell surface.     

Toxicite aigue du vanadium vis-a-vis de quelques especes benthiques et phytoplanctoniques marines

$\text{Acute toxicity of vanadium to some marine benthic and phytoplanktonic species}$The acute toxicity of vanadium as sodium metavanadate to three benthic ($\text{Carcinus}$$\text{maenas}$, $\text{Mytilus}$$\text{galloprovincialis}$, and $\text{Nereis}$$\text{diversicolor}$) and three phytoplankton species ($\text{Dunaliella}$$\text{marina}$, $\text{Prorocentrum}$$\text{micans}$ and $\text{Asterionella}$$\text{japonica}$) were studied. In general the phytoplankton were found to be more sensitive than the benthic organisms used in our experiments. Considering the results from LC₅₀ (9 days) experiments, the organisms, can be classified in the following decreasing order of sensitivity: $\text{D}$. $\text{marina}$ (0.5 ppm), $\text{A}$. $\text{japonica}$ (2 ppm), $\text{P}$. $\text{micans}$ (3 ppm), $\text{N}$. $\text{diversicolor}$ (10 ppm), $\text{C}$. $\text{maenas}$ (35 ppm), $\text{M}$. $\text{galloprovincialis}$ (65 ppm).     

A practical and simple method in fractional determination of ambient forms of mercury in air

A collecting method to prepare a fractional determination of ambient forms of mercury in air is proposed. Particulate mercury is collected by a glass fiber filter. Sequential trap tubes consist of four long and slender quartz tubes, in which the Chromosorb W treated with HC$\text{l}$ gas for Hg(II), the Chromosorb W treated with 0.1 M NaOH for methylmercury, the silver-wire tip for metallic mercury and the gold plate tip for dimethylmercury are packed. The collection efficiency for these trap tubes was in the range of about 85 ～ 100% at the μg or ng concentration level. With this method, the air was collected by suction at the rate of 1.5 $\text{l}$/min. for about five hours, the detection limit being 0.2 ng Hg/m³. The results indicate that the regional distribution of total mercury in air was considerably greater in the volcanic and hot spring regions. Mercury species was found to be mostly Hg(II), followed by metallic mercury, methylmercury, dimethylmercury and particulate mercury in this order.     

Partitioning of mercury in the North Saskatchewan River

Mercury levels in fish, water and sediments were determined during 1982 along a 600 km stretch of the North Saskatchewan River (NSR) in the province of Alberta. Migratory fish species such as goldeye, walleye and sauger in the NSR were found to contain total mercury levels ranging from 0.104 to 1.553 mg/kg ($\text{mean}\text{≧ 0.5}\text{mg}\text{/}\text{kg}$). Northern pike, white sucker, longnose sucker and northern redhorse sucker had total mercury levels ranging from 0.003 to 1.003 mg/kg (mean < 0.5 mg/kg) Regression analysis of the data revealed that neither the sex of the fish nor the location of the sampling site contributed significantly to the mercury burden in fish in the entire study section of the river. Sediment analysis showed a low and more or less uniform concentrations of mercury in Alberta (≦0.1 mg/kg). The total mercury in NSR water averaged 0.09 μg/L in upstream Edmonton and was found to elevate in downstream NSR (0.22 μg/L) near industrial discharge sites and agricultural runoff areas (mean = 0.20 μg/L). Calculated partition coefficients seem to group the fish into two categories, (i) goldeye, walleye and sauger (bioconcentration factor [BCF] =3?3.7×10³ and (ii) northern pike, longnose sucker, white sucker and northern redhorse sucker (BCF=1.2?1.8×10³).     

A baseline study on the concentrations of chlordane-, PCB-and DDT-compounds in Finnish fish samples in the year 1982

113 Fishes (pike, vendace and roach) samples were analyzed for chlordane, PCB-and DDT-compounds. The average concentrations in pike ($\text{Esox lucius}$) muscle tissue in Finnish lakes were 0.05, 0.01 and 0.01 mg/kg wet weight for PCB compounds, total DDT and chlordanes respectively. The results show that chlordanes are evenly distributed in the Finnish environment which indicate that the main part of chlordanes in Finnish fish is due to long range transportation.     

Mercury and methyl mercury in higher fungi and their relation with the substrata in a cinnabar mining area

195 specimens of higher fungi and their substrata collected in the Hg mining area of M.Amiata and around Siena (Central Italy), were analyzed for their total Hg content. Whereas wood decomposers and many species of mycorrhizal fungi accumulated the metal at a very low rate, some mycorrhizal species and all the humus decomposers may accumulate up to 100 μg.g^?1d.w. of Hg and in the least contaminated sites, up to 63 times as much Hg as the substratum. Instead in mineralized areas the concentration factor rarely exceeded 1. The methyl mercury content of 35 species (almost all edible), ranged between 0.01 and 3.7 μg.g^?1 d.w..The possible significance of these findings and the toxicologic implications for local co$\text{n}$ sumers are considered.     

Heavy metal pollution from a point source demonstrated by means of mussels, Mytilusedulis

Heavy metal pollution from a point source has been demonstrated by the levels of mercury in flesh of mussels, $\text{Mytilus}$$\text{edulis}$.     

Mercury induced alterations in the intestinal,absorption of nutrients in the fresh water murrel, Channapunctatus

The effect of five concentrations (10 mM, 1 mM, 0.1 mM, 0.01 mM and 0.001 mM) of mercury on the rate of absorption of glucose, fructose, glycine and tryptophan by the intestine of the fresh water murrel $\text{Channa}$$\text{punctatus}$ has been studied. Intestinal absorption of these nutrients was also examined in fish exposed to a sublethal concentration (3 μg/l) of mercury for 15 and 30 days. Significant decrease was recorded in the rate of intestinal absorption of all the four nutrients with higher concentrations (10 mM, 1 mM and 0.1 mM) of mercury. 0.01 mM and 0.001 mM of mercury also reduced the transport rate but it was insignificant, except in case of tryptophan, where 0.01 mM of mercury also produced significant decrease. Exposure of fish by bath to mercury also resulted in significant decrease in the intestinal transport rate of all the four nutrients after 30 days.     

Fate of 3,3′,4,4′-tetrachloroazobenzene in soybean plants grown in treated soils

Three soils of varying organic matter (OM) concentrations (0, 1.7 and 57%) were treated with 3,3′4,4′-tetrachlorazobenzene (TCAB) at the 25 ppm level. Germinated soybeans$\text{(Glycine}$$\text{max}$ (L.) Merr.) were planted in the treated soils, along with controls, and grown for 12 days. The shoots, roots and soil were air-dried and analyzed for TCAB and 3,3′,4,4′-tetrachloroazoxybenzene (TCAOB). TCAB appears to translocate from the treated soil into the plant shoots and roots. Residue levels varied with the percentage organic matter of each soil; levels as high as 58.4 ppm were identified in roots of soybeans grown in 1.7% OM soil and 0.620 ppm in the shoots from 0% OM soil. TCAOB was identified in soil and root extracts with the highest levels in soybean roots grown in 0% OM soil, 0.317 ppm. Residues of TCAB and TCAOB decreased in soil and root and shoot tissues as percentage OM increased. Bound residues of TCAB were released from roots grown in 0% OM soil by refluxing with boron trifluoride methanol (BF₃CH₃OH).     

Selectivity of Euphorbia lathyris L., to chlortoluron results from the accumulation of the herbicide in the leaves

$\text{Euphorbia lathyris L.}$, was treated for 24 h. with 0.1, 1 and 10 ppm chlortoluron. The induction kinetic of the fluorescence on the whole leaf was registered during the following 15 days. A recovery of $\text{E. lathyris}$ seedlings and an accumulation of chlortoluron in leaves was observed. The fluorescence levels obtained on the leaves emerged after the treatments were similar to the one observed on the control plants. This explains the detoxification mechanism as an accumulation of chlortoluron in the leaves present during the treatment.     

Effect of long term exposure to petroleum on mixed function oxygenases in fish: Further support for use of the enzyme system in biological monitoring

A number of long term, low level petroleum hydrocarbon exposures were carried out from 1978 to 1981 in order to further evaluate use of the mixed function oxygenase (MFO) system in biological monitoring. The studies involved exposure, at ambient temperatures, of fish from three separate families including (a) spawning codfish ($\text{Gadus morhua}$), (b) post-spawned sculpins ($\text{Myoxocephalus octodecemspinosus}$), and (c) gonadally maturing flounder ($\text{Pseudopleuronectes americanus}$). MFO activity remained elevated approximately four-fold in the liver, and three-fold in the gills of codfish exposed for four months to water concentrations of 0.30–0.60 ppm petroleum, at ?1-1°C. Similarly, liver enzyme activity remained elevated approximately three-fold in sculpins exposed to very low levels (0.15–0.20 ppm) of petroleum for three months, at 4–12°C. Results indicate that several years may be required before hydrocarbon concentrations are reduced in petroleum contaminated sediments, such as those heavily impacted by oil spills, to non-inducing threshold levels. Oil contaminated sediment was, even after a year of weathering, quite effective in inducing a high level of MFO activity (seven-fold) in flounder, at 11-6°C. A number of factors that might detract from use of the mixed function oxygenase system in biological monitoring were not realized in these long term studies with petroleum hydrocarbons.     

Removal of alpha-pinene from gases using biofilters containing fungi

Biofiltration is cost-effective for the treatment of gases containing low concentrations of volatile organic compounds $\text{(<3}\text{g}\text{m}{}^{\mathrm{-3}}\text{)}$. However, conventional biofilters, based on compost and bacterial activity, face problems with the elimination of hydrophobic compounds. Besides that, biofilter operational stability is often hampered by acidification and drying out of the filter bed. To overcome these problems, biofilters with fungi on inert packing material have been developed. Fungi are more resistant to acid and dry conditions than bacteria, and it is hypothesised that the aerial mycelia of fungi, which are in direct contact with the gas, can take up hydrophobic compounds faster than flat aqueous bacterial biofilm surfaces. Alpha-pinene was chosen as a model compound. It is an odorous compound emitted by the wood processing industry. In $\text{2}\text{l}$ biofilter columns four different packing materials were tested: perlite, expanded clay granules, polyurethane foam cubes and compost. The filters were inoculated with forest soil and ventilated with gas containing alpha-pinene. Start up took 1–2 months and removal efficiencies of more than 90% were observed, but mostly ranged from 50% to 90% due to overloading. In the filters containing perlite, clay, polyurethane and compost volumetric removal capacities of, respectively, 24, 33, 38 and $\text{24}\text{g}$ alpha-$\text{pinene}\text{m}{}^{\mathrm{-3}}$ filter $\text{bed}\text{h}{}^{\mathrm{-1}}$ were attained and the gas pressure drops in the $\text{60}\text{cm}$ high filter beds measured at a superficial gas velocity of $\text{35}\text{m}\text{h}{}^{\mathrm{-1}}$ were 70, 550, 180 and $\text{250}\text{Pa}$. The results indicate that it is possible to develop biofilters based on the action of fungi with higher elimination capacities for alpha-pinene as reported in literature for bacterial biofilters. The use of polyurethane foam cubes is preferred because of the low gas pressure drop in combination with a high volumetric elimination capacity.     

Effects of tin on sulfhydryl containing enzymes in liver of rats

A single intraperitoneal administration of tin (II) tartrate to albino rats (2 mg $\text{Sn}{}^{\mathrm{++}}\text{100}\text{g}$ body wt) depressed the levels of hepatic glutathione reductase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase, succinic dehydrogenase, reduced glutathione (GSH) and total sulfhydryl contents and led to an elevated level of tin. Serum aminotransferase levels were however, not affected but an increase in serum bilirubin and calcium levels was noticed.$\text{In}$$\text{vitro}$ studies showed that tin tartrate upto a concentration of 2 uM did not affect the activity of liver enzymes tested, when the enzyme preparations were incubated with metallic salts during the time of assay. The critical concentration of tin for these parameters was at 5 uM.     

Toxicity of pH,heavy metals and bisulfite to a freshwater green alga

Low pH markedly reduced the growth and photosynthetic activity of an $\text{Ankistrodesmus}$ sp. The alga could not grow at pH 3 and only slight growth occurred at pH 4. The alga grew well above pH 4 with maximum growth occurring at pH 6. The fixation of ¹⁴CO₂ followed a similar pattern with pH. The algal cells were also sensitive to mercury and bisulfite in acidic conditions. Algal growth and photosynthesis were reduced by mercury and bisulfite more at pH 5 than at pH 7. Lead was relatively non-toxic to the algal cells at both pH levels. Bisulfite inhibited the membrane transport of α-amino-¹⁴C-isobutyric acid at pH 5 but not at pH 7. The results suggest that algal growth and activity may be reduced in acidic lakes by low pH and that the toxicity of mercury and bisulfite is enhanced in acidic conditions.     

Physiological and biochemical responses of several freshwater algae to a mixture of metals

A mixture of ten metals (As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se and Zn) at the Great Lakes Water Quality Objective levels was found to reduce the primary productivity of four cultured freshwater algae ($\text{Scenedesmus}$, $\text{Chlorella}$, $\text{Anabaena}$ and $\text{Navicula}$) as well as natural phytoplankton from Lake Ontario water. The metal mixture also caused a reduction in the reproduction and transport of an amino acid analogue (α-aminoisobutyric acid) by $\text{Ankistrodesmus}$. The depuration and exchange of the amino acid analogue were not affected by the metal mixture. The nitrogenase activity of $\text{Anabaena}$ was, however, reduced in the presence of the metal mixture.     

Oil residues in Baltic sediment,mussel and fish. II. Study of the Finnish Archipelago 1979–1981

Aliphatic hydrocarbons and non-polar aromatic compounds have been analyzed after a spill of grude oil at Baltic Sea 1979 from drifting weathered oil glumps, sediment and sediment trap samples and bivalves at five areas of the Finnish Archipelago Sea. $\text{Mytilus}$ and flounder muscles and flounder livers were analyzed 1980 and 1981 from three of the previous five areas. The glumps were shown to be weathered grude oil. Sediment trap samples on the visibly contaminated area contained higher amounts of oil residues and in different ratios than the bottom sediments at the same areas. Extra local aliphatic hydrocarbon pollution was detected from the sediment traps at the reference area. Bivalves contained high amount of oil residues at visibly polluted but in some visibly non-polluted areas also 1979. Any significant decontamination was not detected at summer 1979 but next year the $\text{Mytilus}$ samples contained only traces if any and 1981 no detectable levels of aromatic oil residues. Aliphatic hydrocarbon residues in flounders showed no regional differences and no significant change of levels between 1980 and 1981. In contrary, the aromatic oil residues decreased to the non-detectable level in flounder muscles and to a significantly lower level in flouder livers 1981 related to 1980. Linear correlations of the analysis results are discussed.     

Photochemistry of pesticides, 3: Photolysis of methyl 2-benzimidazolecarbamate (Carbendazim) in the presence of singlet oxygen

The photolysis of methyl 2-benzimidazolecarbamate (Carbendazim, $\text{1}$) in methanol and in the presence of singlet oxygen, was studied. Dimethyl oxalate $\text{4}$, 2-aminobenzimidazole $\text{7}$, benzimidazole $\text{9}$, N,N′-dicarbomethoxyguanidine $\text{13}$, monocarbomethoxyguanidine $\text{14}$, monocarbomethoxyurea $\text{15}$, and 2-guanidinobenzimidazole $\text{17}$, were isolated and identified in this reaction.A mechanism that accounts for the formation of the photoreaction products, is presented.