Microbial degradation of bis(tributyltin) oxide

The degradation of the biocide bis (tributyltin) oxide by pur cultures of microorganisms has been studied. Attempts to isolate microorganisms able to utilize bis (tributyltin) oxide as sole carbon source, were unsuccessful. Of many bacterial species investigated $\text{Pseudomonas aeruginosa}$ and $\text{Alcaligenes faecalis}$ degraded sublethal amounts of bis (tributyltin) oxide during aerobic growth in the presence of suitable carbon sources. $\text{P. aeruginosa}$ converted bis (tributyltin) oxide into monobutyltin and small amounts of dibutyltin derivatives. Similar results were obtained with growing mycelium of $\text{Coniophora puteana}$, $\text{Trametes versicolor}$ and $\text{Chaetomium globosum}$. Microbial conversion of monobutyltin trichloride was not observed. Dibutyltin dichloride was converted into monobutyltin derivatives under certain sterile conditions.     

Synthesis of anti-12-hydroxyendrin and 12-ketoendrin,the two major mammalian metabolites of endrin

The first synthesis of $\text{syn}$ and $\text{anti}$ 12-hydroxylated derivatives of endrin (and thence 12-ketoendrin) has been accomplished in three steps starting from hexachlorocyclopentadiene and 7-benzoyloxy [2.2.1]hepta-2,5-diene.     

Metabolites of diisopropylnaphthalene in carp Part 2. Invitro experiment

This study described an $\text{in}$$\text{vitro}$ experiment on biotransformation of 2,6-DIPN in carp hepatopancreas. It has already been revealed by the previous $\text{in}$$\text{vivo}$ studies to be metabolized with enzymatic oxidation in the liver and been postulated a metabolic pathway. These results were confirmed by means of incubation with 2,6-DIPN in carp hepatic microsome preparation with NADPH, and G-6-P as co-factor. It was suggested that DIPN may be mainly metabolized in the hepatic cytochrome P-450 in the microsomes system. The kinetic parameters i.e. apparent Michaelis constant (Km) and maximum velocity (Vmax), in the metabolites formation were also calculated.     

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.     

The effect of nitrogen dioxide on the photochemical and nonphotochemical degradation of pyrene and benzo[a]pyrene adsorbed on coal fly ash

Nitration by NO₂ of pyrene or benzo[a]pyrene adsorbed from the vapor phase onto six coal ashes, alumina, and silica substrates is not observed if the NO₂ is thoroughly purged of nitric acid. Also, the photochemical transformation of pyrene or benzo[a]pyrene adsorbed on these substrates is not detectably influenced by the presence of nitric acid-free NO₂. Photochemical production of nitro derivatives of adsorbed polycyclic aromatic hydrocarbons in the presence of NO₂ does not appear to be a significant process unless appreciable concentrations of nitric acid, or perhaps strong oxidants such as ozone, also are present.     

Photochemistry of 1-nitro-2-phenylnaphthalene available to the environment

Photolysis (254 nm, 72h) of 1-nitro-2-phenylnaphthalene $\text{1}$ in methanol gave 2-phenyl-1,4-naphthoquinone-4-monoxime $\text{2}$, 2,2′-diphenyl-4,4′-binaphth-1,1′-diol $\text{3}$ and 2,2′-diphenyl-4,4′-binaphth-1,1′-dione $\text{4}$. Straightforward reactions available to the environment account for the formation of the products: (a) isomerisation of the nitro compound into a nitrite ester followed by either (a) migration of the nitroso group and isomerisation into the oxime $\text{2}$ or (b) oxidative coupling and solvolysis into the binaphthol $\text{3}$ and followed by oxidation into the binaphthone $\text{4}$.     

Comparative aryl hydrocarbon hydroxylase induction activities of commercial PCBs in Wistar rats and rat hepatoma H-4-II E cells in culture

The activities of several commercial PCB mixtures as inducers of microsomal aryl hydroarbon hydroxylase (AHH) and ethoxyresorufin 0-deethylase (EROD) in male Wistar rats and rat hepatoma cells were dependent on the chlorine content (and congener distribution) of the mixtures. The was a correlation between the $\text{in vivo}$ and $\text{in vitro}$ induction potencies of these mixtures; the most active mixtures, Aroclors 1242, 1248 and 1254 contained 42–54% by weight of Cl whereas formulations with higher or lower (Aroclors 1221 and 1268 respectively) chlorine content exhibited lower activities. This corresponds with studies reported for PCB isomers and congeners in which the most active compounds are tetra-hexachlorobiphenyls.     

Effect of cadmium and zinc on intestinal absorption of xylose and tryptophan in the fresh water teleost fish, Heteropneustesfossilis

The effect of cadmium and of zinc on the rate of uptake of a pentose sugar xylose and an aminoacid tryptophan by the intestine of a teleost fish, $\text{Heteropneustes}$$\text{fossilis}$ was studied under two experimental conditions. In the first, four concentrations of cadmium or zinc (1.0 mM, 0.1 mM, 0.01 mM and 0.001 mM) mixed with the nutrient solution were filled in the intestinal sacs, and the rate of absorption was recorded after 1 h at 23°C. In the second experiment fish were exposed by bath to a sublethal concentration of cadmium (0.26 mg/1) or zinc (4 mg/1) for 15 and 30 days and the rate of absorption of the two nutrients was measured. The activity of intestinal Na⁺, K⁺ activated adenosine triphosphatase was also assayed. The two heavy metals at all the four concentrations decreased the rate of intestinal transport of nutrients. Increase in the concentration of each of the heavy metals decreased the uptake of nutrients, but the decreases were not linear. The rate of intestinal absorption of the two nutrients was also reduced by exposure of fish to the heavy metals $\text{in}$$\text{vivo}$. The activity of Na⁺, K⁺ ATPase decreased $\text{in}$$\text{vitro}$ with all four concentrations of cadmium and zinc and was diminished in fish exposed for 15 and 30 days. Of the two heavy metals, cadmium was more effective in reducing the rate of transport of xylose and tryptophan.     

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).     

Factors controlling benzo(a)pyrene concentration in aerosols in the urbanized coastal zone. A case study: Gdynia, Poland (Southern Baltic Sea)

Annual study on the benzo(a)pyrene (BaP) concentration in aerosols in the coastal zone of the Gulf of Gdansk (southern Baltic) has been performed at Gdynia station. Combustion processes, especially domestic heating of both local and regional origin, were identified as the main sources of benzo(a)pyrene in this area. Concentrations observed during the heating season (mean 2.18 ng?m^?3) were significantly higher than these recorded in the non-heating season (mean 0.05 ng?m^?3). High benzo(a)pyrene concentrations were associated with low temperature and high humidity. Whereas high levels of precipitation usually decreased the BaP concentration in aerosols. The concentration of this factor in the studied area depended also on the wind direction and air masses trajectories. During heating season, continental air masses (coming from S, SE, SW) seemed to increase benzo(a)pyrene concentration, while maritime air masses (from N, NE, NW) caused its decrease. The differences in the BaP concentration resulting from potentially different emission levels of this compound during working and non-working days were not clearly pronounced.     

Environmental photochemistry of PCDDs. Part I. Kinetics and quantum yields of the photodegration of 1,2,3,4,7-penta- and 1,2,3,4,7,8-hexachlorodibenzo-p-dixin in aqueous acetontrile

For the determination of the quantum yields of 1,2,3,4,7-pentachlorodibenzo-$\text{p}$-dioxin ($\text{1}$) and 1,2,3,4,7,8-hexachlorodibenzo-$\text{p}$-dioxin ($\text{2}$), ten Pyrex glass photochemical cells were constructed and their correction factors determined. Quantum yields at 313 nm for $\text{1}$ and $\text{2}$ in aqueous acetonitrile (4:6 v/v) were (9.781 ± 2.376) 10^?5 and (1.096 ± 0.020) × 10^?4, respectively. These quantum yields and the measured absorption spectra were used to estimate the environmental phototransformation first-order rate constants and photochemical half-lives of $\text{1}$ and $\text{2}$ in water under conditions of variable sunlight intensity during various seasons from solar intensity data available in the literature. In summer, typical half-lives for the phototransformation of $\text{1}$ and $\text{2}$, respectively, near the surface of water bodies at 40° north latitude would be 364 ± 88 and 151 ± 3 h; whilst such values in winter would be 1257 ± 309 and 518 ± 10 h.     

Substitutes for phosphate containing washing products: Their toxicity and biodegradability in the aquatic environment

The toxicity of nitrolotriacetic acid (NTA), citrex-S-5, sodium alluminium silicate (NAS), carboxymethyloxysuccinate (CMOS), linear alkylbenzene sulfonate (LAS) and soap was examined using bacteria ($\text{Pseudomonas}$$\text{fluorescens}$), algae ($\text{Chlorella}$$\text{vulgaris}$ and $\text{Microcystis}$$\text{aeruginosa}$), crustaceans ($\text{Daphnia}$$\text{magna}$), insects ($\text{Aedes}$$\text{aegypti}$), fishes ($\text{Poecilia}$$\text{reticulata}$ and $\text{Oryzias}$$\text{latipes}$) and amphibians ($\text{Xenopus}$$\text{laevis}$). The biodegradability of NTA, citrex-S-5, CMOS and LAS was studied in the OECD-test.The acute toxicity of the compounds differed largely with the organisms tested (up to a factor 1,000). Based on the results of the short-term toxicity tests (with all test organisms) and the long-term toxicity tests (with $\text{Daphnia}$$\text{magna}$ and in case of LAS also with $\text{Poecilia}$$\text{reticulata}$) the following no-observed-effect concentrations (NOEC) could be derived: LAS 3.2 mg/1; NAS and soap 10 mg/1; CMOS 32 mg/1; NTA 100 mg/1 and citrex-S-5 320 mg/1. However, testing different samples of one test compound may result in marked differences in toxicity (e.g. NAS: a factor 32).All compounds tested showed to be biodegradable as the percentage DOC decreased more than 80% within four weeks. CMOS biodegraded quickly, whereas citrex-S-5 and LAS showed a somewhat slower rate of degradation. In contrast to the other compounds NTA required an adaptation period of 1 week.     

Soil mobility of surface applied polyaromatic hydrocarbons in response to simulated rainfall

Polyaromatic hydrocarbons (PAHs) are emitted from a variety of sources and can accumulate on and within surface soil layers. To investigate the level of potential risk posed by surface contaminated soils, vertical soil column experiments were conducted to assess the mobility, when leached with simulated rainwater, of six selected PAHs (naphthalene, phenanthrene, fluoranthene, pyrene, benzo(e)pyrene and benzo(ghi)perylene) with contrasting hydrophobic characteristics and molecular weights/sizes. The only PAH found in the leachate within the experimental period of 26 days was naphthalene. The lack of migration of the other applied PAHs was consistent with their low mobilities within the soil columns which generally paralleled their log K _oc values. Thus, only 2.3 % of fluoranthene, 1.8 % of pyrene, 0.2 % of benzo(e)pyrene and 0.4 % of benzo(ghi)perylene were translocated below the surface layer. The PAH distributions in the soil columns followed decreasing power relationships with 90 % reductions in the starting levels being shown to occur within a maximum average depth of 0.94 cm compared to an average starting depth of 0.5 cm. A simple predictive model identifies the extensive time periods, in excess of 10 years, required to mobilise 50 % of the benzo(e)pyrene and benzo(ghi)perylene from the surface soil layer. Although this reduces to between 2 and 7 years for fluoranthene and pyrene, it is concluded that the possibility of surface-applied PAHs reaching and contaminating a groundwater aquifer is unlikely.     

Kinetics of oxidation of methylhydrazines in water. Factors controlling the formation of 1,1-dimethylnitrosamine

The kinetics of oxidation of methylhydrazine ($\text{MMH}$) and 1,1-dimethylhydrazine ($\text{UDMH}$) by dissolved oxygen in water has been measured at various acidities as a function of catalyst (cupric ion) concentration. In dilute solutions the oxidation occurs through a cupric ion catalyzed process as well as by an uncatalyzed step. The extent of formation of nitrosodimethylamine ($\text{NDMA}$) depends upon the initial $\text{UDMH}$ concentration. In dilute solutions $\text{NDMA}$ is not formed, but in more concentrated solutions, $\text{NDMA}$ formation increases with increasing $\text{UDMH}$ content, reaches a maximum at 60–80% $\text{UDMH}$ (by volume) and then decreases. The $\text{NDMA}$ yield appears to approximately parallel the viscosity of the medium, and it is speculated that the factors which control viscosity may also be responsible for governing $\text{NDMA}$ formation.     

Phase distribution and artifact formation in ambient air sampling for polynuclear aromatic hydrocarbons

Laboratory and field sampling experiments were conducted to determine the phase-distribution of polynuclear aromatic hydrocarbons (PAH) in the ambient atmosphere and to determine the potential for artifact formation due to volatilization and ozone (O₃) reaction during normal sampling conditions. The study was conducted in two segments to investigate both summer and winter ambient temperature effects. The winter measurements reflect stronger association of PAH with the particulate phase than the summer data, but data from both seasons show appreciable filter losses due to volatilization of phenanthrene, anthracene, fluoranthene, benz(a)anthracene and chrysene. No evidence was found for volatilization of the heavier PAH, including benzo(e)pyrene, benzo(a)pyrene, indeno(l,2,3-c,d)pyrene, benzo(g,h,i)perylene and coronene. Although O₃ reacted readily with particulate matter that was freshly spiked with PAH in the laboratory experiments, no evidence was found for reaction of O₃ with particulate matter during the field sampling experiments.     

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.     

Effect of fungicidal seed treatments on alfalfa growth and nodulation by Rhizobiummeliloti

A study of the effect of 5 fungicide seed treatments on alfalfa ($\text{Medicago}$$\text{sativa}$ L. var. Vernal) growth and nodulation by $\text{Rhizobium}$$\text{meliloti}$ 102F66 was conducted in a growth chamber. Captan, maneb and thiram exhibited greater toxicity to $\text{R}$. $\text{meliloti}$ and alfalfa plants than that of benomyl and zineb. Recovery of the inhibitory effect was rapid.