Synthesis of branched para-nonylphenol isomers: occurrence and quantification in two commercial mixtures

Eight tertiary nonanols were synthesized via Grignard reaction and coupled by Friedel–Crafts alkylation with phenol to the corresponding nonylphenols. Six branched para-nonylphenols (NP) were obtained: 4-(3′-methyl-3′-octyl)phenol (33NP), 4-(2′-methyl-2′-octyl)phenol (22NP), 4-(2′,5′-dimethyl-2′-heptyl)phenol (252NP), 4-(2′,5′,5′-trimethyl-2′-hexyl)phenol (2552NP), 4-(2′,4′-dimethyl-2′-heptyl)phenol (242NP) and 4-(4′-ethyl-2′-methyl-2′-hexyl)phenol (4E22NP). Their structures were confirmed by GC–MS and NMR spectroscopy. These six isomers as well as the earlier synthesized 4-(3′,5′-dimethyl-3′-heptyl)phenol (353NP), 4-(3′,6′-dimethyl-3′-heptyl)phenol (363NP) and 4-(2′,6′-dimethyl-2′-heptyl)phenol (262NP) were compared with commercial NP mixtures purchased from Acros and Fluka by GC–MS (equipped with a 100 m polysiloxane column). The analyses revealed that all obtained isomers are occurring in different quantities in both commercial NP mixtures.     

Tissue retention and metabolism of 2,3,4,3′,4′-pentachlorobiphenyl in mink and mouse

2,3,4,3′,4′-Pentachlorobiphenyl was retained as the unmetabolized parent compound in liver and fat from mouse and mink. In contrast, in mouse plasma - 4-hydroxy-2,3,5,3′,4′-pentachlorobiphenyl - was present in concentrations 15 times higher than that of the parent chlorobiphenyl. In mink plasma the parent compound and the 4-hydroxylated metabolite were present in similar concentrations. Faeces was the major excretion pathway in both animals. Both the mouse and the mink excreted mainly the parent compound accompanied by trace amounts of hydroxylated metabolites but the mink also excreted significant amounts of hydrophilic metabolites, that gave hydroxylated products after acidic hydrolysis. Five hydroxylated metabolites, 4-hydroxy-2,3,5,3′,4′-pentachlorobiphenyl, 4-hydroxy-3,5,2′,3′,4′-pentachlorobiphenyl, 2-hydroxy-3,4,2′,3′,4′-pentachlorobiphenyl, 5-hydroxy-3,4,2′,3′,4′-pentachlorobiphenyl and 5-hydroxy-2,3,4,3′,4′-pentachlorobiphenyl, were identified in excreta of mink and mouse.     

Contents and origin of polychlorinated diphenyl ethers (PCDE) in salmon from the Baltic Sea, Lake Saimaa and the Tenojoki river in Finland

The presence of 26 congeners of polychlorinated diphenyl ethers (PCDEs) was investigated in salmon from three locations in Finland. In addition to salmon, one chlorophenol wood preservative (Ky-5) and one fly ash sample were analyzed for PCDEs. Concentrations of PCDE congeners in salmon muscle measured by high resolution gas chromatography/low resolution mass spectrometry ranged from < 0.02 to 2.4 ng/g fresh weight. The major components of tetra- to octachlorinated PCDEs in salmon were one TeCDE (22′44′-), two PeCDEs (22′44′5- and 23′44′5-) and three HxCDEs (22′44′56′-, 22′44′55′- and 22′344′5-). The Baltic salmon caught from the Simojoki River had higher levels of PCDEs than the Atlantic salmon from the Tenojoki River or salmon from Lake Saimaa in South-Finland. Same PCDE congeners which were abundant in the wood preservative were also detected in salmon, whereas PCDE congeners in the fly ash were different from those in salmon or in Ky-5.     

Reductive dechlorination of non-ortho substituted polychlorinated biphenyls by ultraviolet irradiation in alkaline 2-propanol

The photodechlorination pathways of 3,3′,4,5,5′-pentachlorobiphenyl (3,3′,4,5,5′-PentaCB) and the related lower polychlorinated biphenyl congeners irradiated at 254 nm in alkaline 2-propanol were elucidated. Steric effect is the most important factor for controlling the dechlorination pattern of these substrates. Electronic effect also influences the photoreactivity of chlorine substituents.     

Organochlorine pesticides and polychlorinated biphenyl congeners in wild terrestrial mammals and birds from Chubu region, Japan: Interspecies comparison of the residue levels and compositions

In order to understand the residue levels of organochlorine compounds (OCs) and their accumulation patterns in wildlife inhabiting Chubu region, Japan, the concentrations of polychlorinated biphenyls (PCBs), hexachlorocyclohexane isomers (HCHs), DDT compounds (DDTs) and hexachlorobenzene (HCB) were measured in 8 species of terrestrial mammals and 10 species of birds. In view of feeding habits, the contamination levels of OCs were found to be higher in omnivorous mammals than in herbivorous ones, and in fish-eating ones and raptores than in omnivorous birds. In fox and dog, PCB-180 (2, 2′, 3, 4, 4′, 5, 5′-heptachlorobiphenyl) was the most dominant PCB congener, while in the other species PCB-153 (2, 2′, 4, 4′, 5, 5′-hexachlorobiphenyl) was the most persistent. The ratios of lower chlorinated PCB congeners (tri- to tetra-) to total PCBs were larger in fish-eating birds than in the other birds. The results indicate that the compositions of PCB congeners would reflect the differences of feeding habits and xenobiotic metabolizing systems among each species.     

Determination of the toxic impurities 3,3′,4,4′-tetrachloroazobenzene and 3,3′,4,4′-tetrachloroazoxybenzent in commercial diuron, linuron and 3,4-dichloroaniline samples

Methods are described for the determination of 3,3′,4,4′-tetrachloroazobenzene (TCAB) and 3,3′,4,4′-tetrachloroazoxybenzene (TCAOB) in diuron and linuron formulations and in 3,4-dichloroaniline. The formulations were extracted with acetone, and after removal of solvent, the residue was partitioned between methanol-water and hexane. 3,4-Dichloroaniline products were partitioned between methanol-1M hydrochloric acid and hexane. The hexane extracts were purified by column chromatography on silica gel and analysed by gas chromatography with electron-capture detection. Detection limits for TCAB and TCAOB were around 0.1 ug/g using samples of one gram. Levels of 5.5 – 28 ug TCAB and 1.9 − < 0.05 ug TCAOB/g herbicide formulation and 2.4 – 460 ug TCAB/g TCAB/g 3,4-dichloroaniline have been found. TCAOB levels were below the detection limits in the 3,4-dichloroaniline samples. The presence of TCAB and TCAOB was confirmed by gas chromatography-mass spectrometry.     

3,3′,4,4′-Tetrachlorobiphenyl in human fat and milk samples

Samples of adipose tissue from 7 male persons and 10 samples of human milk were analyzed for 3,3′,4,4′-tetrachlorobiphenyl by HRGC-HRMS. The levels found are in the lower ppt-range on a fat weight basis     

Organochlorinated pesticides in sediments from the Lake Albufera of Valencia (Spain)

Bottom sediment samples from 121 sites of the Lake Albufera of Valencia were analyzed. Dieldrin, endrin, heptachlor and op′-DDT were not detected (<0.01 ng g⁻¹) in 88–93% of the sites. Aldrin and HCB concentration ranges were between <0.01 and 0.1 ng g⁻¹ in 86% and 94% of the sites, respectively. Heptachlor-epoxide and lindane 95% confidence intervals were 0.2–0.5 and 0.06–0.12, respectively. The greatest average concentration corresponds to pp′-DDE, pp′-DDD and pp′-DDT. The sum of six isomers and derivatives of the DDT average concentration reaches 2.1 ng g⁻¹, as opposed to 2.7 ng g⁻¹ for the sum of 13 pesticides considered. In the site with a major contamination, 27.0 ng g⁻¹ of pp′-DDD and 12.8 ng g⁻¹ of pp′-DDT were accumulated. The DDE:DDT proportion average was 0.37, indicating an aged DDT contamination. Concentrations of pesticides in sediments were compared to three sediment quality guidelines, and indicated that a low biological effects level can be expected in either sediments or aquatic organisms.     

Brominated-chlorinated diphenyl ethers formed by thermolysis of polybrominated diphenyl ethers at low temperatures

Polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants (BFRs) used mainly as additives in different kinds of plastic material. Various PBDEs are found in all environmental compartments as well as in tissue and blood serum of animals and humans due to their persistence and tendency to bioaccumulate. Emission of PBDEs into the environment can occur during recycling of PBDE-containing plastic material or during their uncontrolled or insufficient combustion as e.g. in accidental fires or landfill fires. Under these circumstances, PBDEs can also function as precursor molecules for the formation of polybrominated dibenzodioxins (PBDDs) and dibenzofurans (PBDFs). In this study, we qualitatively investigated the reaction of two PBDE congeners, 2,2′,4,4′-tetrabromo diphenyl ether (BDE 47) and 2,2′,4,4′,5,5′-hexabromo diphenyl ether (BDE 153), as well as hexabromobenzene (HBB), a flame retardant used in the past, when exposed to temperatures between 250 °C and 500 °C. The formed reaction products were analysed by high resolution gas chromatography–low resolution mass spectrometry (HRGC-LRMS). Among others brominated–chlorinated diphenyl ethers were formed by chlorodebromination of the PBDEs. In addition, thermolysis of BDE 47 and BDE 153 in the presence of tetrachloromethane as model substance for an organic chlorine source was studied. Thermal treatment of HBB resulted in the formation of brominated–chlorinated benzenes.     

Interactions of 2,2′,4,4′,5,5′-hexachlorobiphenyl and 2,3,7,8-tetrachlorodibenzo-p-dioxin in a subchronic feeding study in the rat

Female (SD) rats were fed diets containing 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB 153) in various concentrations for three months. PCB 153 had no significant effect on the body weight gain when given alone or in combination with TCDD. The increases in relative liver weights were additive. For thymic atrophy no interactive effects became apparent. PCB 153 had no effect on the EROD induction by TCDD. PROD induction by PCB 153 was diminished in the presence of TCDD. The level of TCDD in the liver was decreased by PCB 153. Increasing TCDD dosage led to an increase in PCB 153 levels.     

Organochlorine compounds in a three-step terrestrial food chain

The concentrations of 15 organochlorine chemicals (PCBs and pesticides) were studied in a Central European oak wood food chain system: Great tit (Parus major), caterpillars (Tortrix viridana, Operophtera brumata, Erannis defoliaria), and oak-leaves (Quercus robur). Juvenile tits receive organochlorines from the mother via egg transfer and, eventually to a greater extent, from the caterpillar food source during nestling period. The concentrations of PCB 153 (2,2′,4,4′,5,5′-hexachlorobiphenyl, the most abundant in this study) was found in leaf material at ca. 1 ng/g, in caterpillars 10 ng/g, and in bird eggs 170 ng/g on an average and on a dry mass basis.     

Levels of 3,3′,4,4′-tetrachloroazobenzene in herbicides and bulk reagents

The contamination levels of different commercial herbicides and bulk reagents with the carcinogen 3,3′,4,4′-tetrachloroazobenzene (TCAB) were determined by high resolution mass spectrometry. The concentrations vary from 0.00071 to 2.8 ug/g (ppm) for the herbicides and from 0.085 to 14 ug/g for the bulk reagents. They are thus lower than those of other reports.     

Organochlorine pesticides accumulation and degradation products in vegetation samples of a contaminated area in Galicia (NW Spain)

The content of 21 organochlorine pesticides were studied in vegetation samples of a highly contaminated area by isomers of hexachlorocyclohexane (HCH) located close to a former industrial area in Galicia (NW Spain). Five species of plants were collected at different points of the contaminated area and the different parts of the plants were separated in order to study differences in accumulation capabilities. Samples were extracted employing microwave energy followed by a clean-up step using solid phase extraction and finally determined by GC–ECD. The results obtained show that the most abundant pesticides are HCHs isomers, being the main isomers β-HCH and -HCH in all samples whereas δ-HCH and γ-HCH were at lower levels. Some other pesticides such as p,p′-DDT, p,p′-DDD and p,p′-DDE were also present in much lower amount in some of the samples. Several degradation products of HCH were also identified in some samples by GC–MS.     

Screening 31 endocrine-disrupting pesticides in water and surface sediment samples from Beijing Guanting reservoir

For screening 31 potential or suspected endocrine-disrupting pesticides in water and surface sediments, a multiresidue analysis method based on gas chromatography with electron capture detection (GC/ECD) was developed. Solid phase extraction (SPE) technology with Oasis^® HLB cartridge was also applied in sample extraction. The relevant mean recoveries were 70–103% and 71–103% for water and sediment, respectively. Relative standard deviations (RSD) are 2.0–7.0%, 4.0–8.0% for water and sediment, respectively. Thirty one pesticides (-HCH, β-HCH, γ-HCH, δ-HCH, hexachlorobenzene (HCB), aldrin, heptachlor, endosulfan I & II, p,p′-DDD, o,p′-DDT, p,p′-DDT, p,p′-DDE, endrin aldehyde, endosulfan sulphate, methoxychlor, hepachlor epoxide, -chlordane, γ-chlordane, dieldrin, endrin, dicofol, acetochlor, alachlor, metolachlor, chlorpyriphos, nitrofen, trifluralin, cypermethrin, fenvalerate, deltamethrin) in water and surface sediment samples from Beijing Guanting reservoir were analyzed. Concentrations of pesticides ranged from 7.59 to 36.0 ng g⁻¹ on a dry wt. basis for sediment samples, from 279.3 to 2740 ng l⁻¹ for pore waters and from 48.8 to 890 ng l⁻¹ for water samples, respectively, with a mean concentration of 10.7 ng g⁻¹ in sediment, 735 ng l⁻¹ in pore water and 295 ng l⁻¹ in water, respectively. The data obtained provides information on the levels and sources of endocrine-disrupting pesticides in Guanting reservoir. These results underscore the need to improved environmental protection measures in order to reduce the exposure of the population and aquatic biota to these endocrine-disrupting compounds.     

A survey of PCB congeners in U.K. cows'' milk

Samples of unpasteurised bulked milk, taken directly from ten herds of dairy cattle on rural and urban farms in the north west of England on five separate sampling occasions, were analysed for a range of PCB congeners. ΣPCB concentrations (sum of 37 congeners) ranged from 3.4–16.4 ng/g milk fat with a mean ΣPCB concentration of 8.4 ng/g milk fat. The dominating congeners were 118, 153, 138 and 180, which contributed 15%, 20%, 17% and 9% of the ΣPCB load respectively. The chlorine pattern of the congeners which made moderate or major contributions to the ΣPCB concentration were typically substituted at both para positions (4, 4′), while the PCB congeners not detected in the milk had at least one ring that was not 4-substituted. These results indicate the 4,4′ substitution pattern as being the key to PCB persistence in cows. It is estimated that consumption of typical daily intakes of milk with the PCB concentrations measured in this study would contribute 11 % of the average daily ΣPCB intake for individuals in the UK. This contribution would increase to 30% when exposure through the consumption of dairy products prepared from such milk (e.g. cheese, butter) is taken into account. It is estimated that the inclusion of the TEF assigned PCBs would typically increase the TEQ rating of cows' milk by approximately 40% over that attributed to PCDD/Fs alone.     

Herbicide effects on typha latifolia (Linneaus) germination and root and shoot development

Aqueous 7-d germination and growth experiments were performed to compare responses of T. latifolia to exposures of atrazine (2-chloro-4-ethylamino-6-isopropylamine-s-atrazine) and paraquat dichloride (1,1′-dimethyl-4,4′-bipyridinium dichloride). T. latifolia seed germination was < 50 % in concentrations ≥ 1.0 mg/L of paraquat dichloride. No observed effect concentration (NOEC) and lowest observed effect concentration (LOEC) for paraquat and root growth were 0.001 and 0.01 mg/L, respectively, while NOEC and LOEC for paraquat and shoot growth were 0.01 and 0.1 mg/L, respectively following 7-d exposures. Greater than 72 % of seeds germinated in each concentration up to 30 mg/L atrazine. After 7-d exposure, NOEC and LOEC for atrazine and root growth were 0.1 and 1.0 mg/L, while atrazine and shoot growth NOEC and LOEC values were 15 and 30 mg/L, respectively. This research provides data concerning relative sensitivity of T. latifolia seedlings to the herbicides atrazine and paraquat, as well as the potential use of T. latifolia as a representative plant test species.     

Cold season CH4, CO2 and N2O fluxes from freshwater marshes in northeast China

Cold season (winter and thaw) CH₄, CO₂ and N₂O fluxes from freshwater marshes (47°35′N, 133°31′E, Northeast China) were measured, using the static chamber method. The mean CH₄ and CO₂ fluxes from Carex lasiocarpa (Cl) were 0.5 ± 0.19 and 6.23 ± 1.36 mg C m⁻² h⁻¹, respectively, and those from Deyeuxia angustifoli (Da) were 0.18 ± 0.15 and 5.22 ± 2.48 mg C m⁻² h⁻¹, respectively in winter. There was no significant difference between Cl and Da (p > 0.05). The contributions of winter CH₄ fluxes were about 5.5% and 3% in the Cl and Da, respectively. Marshes are an important potential N₂O sink in winter season in northeast China. During thaw, the CH₄ and CO₂ emissions rapidly increased, 4.5–6 times of winter emissions. Wetland became a source of N₂O. Cold season gases flux from northern wetlands play an important role in the seasonal gas exchange.     

Comparisons of coarse and fine versions of two carbons for reducing the bioavailabilities of sediment-bound hydrophobic organic contaminants

Coarse (whole) and finely ground Ambersorb 1500 and coarse and fine coconut charcoal were compared as to their efficiencies in scavenging organic contaminants desorbed from sediment. Aqueous slurries of a test sediment spiked (1 ppm) with p,p^′-DDE (DDE), 2,2^′,5,5^′-tetrachlorobiphenyl (TCB), naphthalene (NAP), or phenanthrene (PHEN), and containing 1% levels of the test carbons were treated by shaking at 35 °C while exposed to clusters of low-density polyethylene membrane (detox spiders). Controls consisted of spiked sediments and detox spiders but no added carbon of any kind and thus represented unimpeded bioavailabilities (to the spiders). After the treatments––agitation periods from 2.5 to 60 h, depending on contaminant hydrophobicity––the exposed detox spiders were analyzed. The fine carbon of either type was more effective than its coarser variant in obstructing contaminant bioavailabilities. The finer variants of both carbons obstructed the bioavailabilities of NAP and PHEN equally well as did the coarser variants of both. Whole Ambersorb 1500 and coarse coconut charcoal were similarly ineffective in intercepting TCB and DDE. Ground Ambersorb 1500 obstructed virtually all bioavailability of all four contaminants and was far more effective than fine coconut charcoal in intercepting DDE and TCB. An additional experiment compared the effectiveness of ground Ambersorb 1500 and fine coconut charcoal in obstructing the bioavailabilities from sediment of a broad array of spiked organochlorine pesticides. The performance of ground Ambersorb 1500 was again found to be superior; the bioavailable levels of each of the 27 pesticides were markedly lower in the presence of ground Ambersorb 1500 than in the presence of fine coconut charcoal.     

Partial solubility parameters of chlorobenzene and chlorophenol compounds at equilibrium distribution in two immiscible phases

Partial solubility parameters of chlorobenzene and chlorophenol compounds at equilibrium distribution in two immiscible phases such as soil-water system were studied. An integral distribution equilibrium equation is derived from the concept of partial solubility parameters and Flory-Hungins equation. Twelve chlorobenzenes and nineteen chlorophenols were employed in this study and their partial solubility parameters including dispersion( (δ_d),and polar van der Waals (δ_p), as well as their electron acceptor and donor solubility parameters (δ_a and δ_b) were calculated.Hildebrand's solubility parameter(δ) of the compounds was also obtained by using boiling point and formula.HPLC was performed by octadecyl-bonded phase as the stationary phase with methanol or acetonitrile as the mobile phase to determine the capacity factor k′ of all compounds for the calculation of δ_a and δ_b.     

A simple effective procedure for the determination of adenosine triphosphate in soils

A simple method for the extraction and determination of adenosine 5′-triphosphate (ATP) in soil is described. ATP was extracted by stirring with dimethyl sulphoxide (DMSO), followed by adding 0.01 M trisodium phosphate (Na₃PO₄) buffer solution for a further dispersion. The ATP content was quantitatively measured by luciferin-luciferase system employing a standard addition technique. The method was most efficient in comparison with 7 other extraction procedures. The recoveries of ATP in spiked soil were found to be approximately 100 %. ATP contents in 16 selected soils were in ranges of 0.76±0.05 – 7.79±0.83 μg/g (dry weight). A significant correlation between ATP amounts and biomasses in these soils was also observed.