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Abstract: A direct immersion solid-phase microextraction coupled with gas chromatography-electron capture detection (SPME-GC-ECD) method was optimized and validated for the quantitative determination of 18 organochlorine pesticides in ground water. Ionic strength, stirring speed, adsorption and desorption time and pH were some of the parameters investigated in order to select the optimum conditions for SPME with a 50/30 DVB/CAR/PDMS fiber coating. The SPME-GC/ECD method showed good linear response below 10ngL−1 with R 2 values in the range of 0.9950–0.9997. The repeatability of the measurements were lower than 10%. Values of relative recoveries located within the acceptable range (80–120%). Limits of quantification (LOQ) from 4.5×10−3 to 1.5ngL−1 were obtained. On average 8 organochlorines were found per sample, even so all the 18 organochlorines were quantified among them. Substances such as endrin ketone, γ-BHC and β-BHC were the pesticides determined in larger concentration (0.06–305ngL−1), while methoxychlor and aldrin in smaller amounts (0.151–1.55ngL−1). Measured levels of organochlorine pesticides were above the limits established by Brazilian regulations. [Copyright &y& Elsevier]

Abstract: Fourteen samples of particulate matter and semi-volatile organic compounds were collected during 6 months in the city of Campo Grande, South Mato Grosso State, Brazil. Particle-bound polycyclic aromatic hydrocarbons (PAHs) were collected on Fluoropore PTFE filters and gas-phase PAHs were collected into sorbent tubes with XAD-2 resin. Both types of samples were extracted with a dichloromethane/methanol mixture (4:1v/v), then the extracts were subjected to gas chromatography–mass spectrometry (GC–MS) analysis. PAHs, oxidized PAH (oxy-PAHs), phenols and methoxyphenols were identified by use of GC retention indices and MS files. The average value obtained for the sum of 15 PAHs was 21.05ngm−3 (range: 8.94–62.5ngm−3). The presence of specific tracers and calculations of characteristic ratios (e.g. [Phe]/[Phe]+[Ant]) were used to identify the sources of the emissions of PAHs in the atmospheric samples. Levoglucosan (the anhydride of β-glucose), retene (1-methyl-7-isopropylphenanthrene) and methoxyphenols (derivatives of syringol and guaiacol) and tracers for wood burning were identified. This study demonstrates that biomass burning from the rural zone is the main source of PAHs and emissions of other substances in the investigated site of Campo Grande. [Copyright &y& Elsevier]

The essential oils obtained from the flowers from Campomanesia sessiliflora and Campomanesia xanthocarpa were analyzed by GC and GC/MS. Thirty-seven and 34 components were identified in the fruit oil of Campomanesia sessiliflora and Campomanesia xanthocarpa, respectively. In two species the major constituent was ledol (15.6-18.9%). [ABSTRACT FROM AUTHOR]

The essential oils obtained of the fruits from Campomanesia xanthocarpa and Campomanesia adamantium (Myrtaceae) were analyzed by GC and GC/MS. Thirty-seven and 38 components were identified in the fruit oil of C. xanthocarpa and C. adamantium, respectively. In the two species, the major constituent was cryptomeridiol (11.9-19.2%). [ABSTRACT FROM AUTHOR]

The essential oils obtained from the leaves and flowers from Campomanesia adamantium (Myrtaceae) collected in the Mato Grosso do Sul in the flowering stage were analyzed by GC and GC/MS. Eighty-two components were identified in the leaf oil and thirty-seven in the flower oil. The constituent major in the leaf oil was limonene (21.9%) and in the flower oil was ledol (20.9%). [ABSTRACT FROM AUTHOR]

The essential oil obtained from the leaves of Campomanesia sessiliflora (Myrtaceae) collected in the Mato Grosso do Sul in the vegetative stage was analyzed by GC and GC/MS. Thirty-nine components were identified in the leaf oil. The major constituents in the leaf oil were bicyclogermacrene (22.4%), spathulenol (15.9%) and germacrene D (14.6%). [ABSTRACT FROM AUTHOR]

The essential oil obtained from the leaves of Anacardium humile (Anacardiaceae) were analyzed by GC and GC/MS. Thirty-five compounds were identified in the leaf oil. The major constituents in the leaf oil were α-bulnesene (8.6%), γ-cadinene (7.5%), selina-3,7(11)-diene (6.7%), α-himachalene (6.1%) and cyperene (5.0%). [ABSTRACT FROM AUTHOR]

The essential oil obtained of the flowers from Campomanesia pubescens (Myrtaceae) was analyzed by GC and GC/ MS. Thirty-eight compounds were identified in the flower oil of Campomanesia pubescens. The major constituents in the flower oil were ledol (19.8%), globulol (9.2%), α-cadinol (7.3%) and epi-α-muurolol (5.0%). [ABSTRACT FROM AUTHOR]

The essential oils obtained from the fruits of Campomanesia pubescens O. Berg (Myrtaceae) collected in the Mato Grosso do Sul were analyzed by GC and GC/MS. Thirty-eight components were identified in the fruit oil. The major constituent was cryptomeridiol (14.2%). [ABSTRACT FROM AUTHOR]

A direct immersion solid-phase microextraction coupled with gas chromatography-electron capture detection (SPME-GC-ECD) method was optimized and validated for the quantitative determination of 18 organochlorine pesticides in ground water. Ionic strength, stirring speed, adsorption and desorption time and pH were some of the parameters investigated in order to select the optimum conditions for SPME with a 50/30 DVB/CAR/PDMS fiber coating. The SPME-GC/ECD method showed good linear response below 10 ng L(-1) with R(2) values in the range of 0.9950-0.9997. The repeatability of the measurements were lower than 10%. Values of relative recoveries located within the acceptable range (80-120%). Limits of quantification (LOQ) from 4.5x10(-3) to 1.5 ng L(-1) were obtained. On average 8 organochlorines were found per sample, even so all the 18 organochlorines were quantified among them. Substances such as endrin ketone, gamma-BHC and beta-BHC were the pesticides determined in larger concentration (0.06-305 ng L(-1)), while methoxychlor and aldrin in smaller amounts (0.151-1.55 ng L(-1)). Measured levels of organochlorine pesticides were above the limits established by Brazilian regulations.

Polycyclic aromatic hydrocarbons (PAH) were measured in smoke samples from wood carbonization during charcoal production, in both particulate matter (PM) and gaseous phases. Samples were acquired using a medium-volume air sampler at 1.5 m distance from the furnace. Particle-bound PAH were collected on Fluoropore polytetrafluoroethylene filters and gas-phase PAH were collected into sorbent tubes with XAD-2 resin. PAH were extracted with dichloromethane-methanol and analyzed using gas chromatography-mass spectrometry. The results showed total emission from the furnace of 26 microg/m3 for the 16 PAH and 2.8 microg/m3 for the 10 genotoxic PAH (from fluoranthene to benzo[g,h,i]perylene). High emission of 16 PAH in the first 8 h of wood carbonization was detected (64 microg/m3; 56% of the total emission). Associated with PM, 11% of the total emission of 16 PAH (in both phases) and 60% of 10 genotoxic PAH were found. Relative ratios (for example, [Phe]/[Phe]+[Ant]) for the PAH of the same molecular weight were obtained and compared with the published data. The concentrations of benzo[a]pyrene equivalent (BaP(eq)) were estimated using the list of toxic equivalent factors suggested by . The values of 0.30 and 0.06 mg/m3 were obtained for the total concentrations of BaP(eq) in PM and gaseous phase, respectively.