Brominated flame retardants in the Australian population: 1993-2009

Brominated flame retardants, including hexabromocyclododecane (HBCD) and polybrominated diphenyl ethers (PBDEs) are used to reduce the flammability of a multitude of electrical and electronic products, textiles and foams. The use of selected PBDEs has ceased, however, use of decaBDE and HBCD continues. While elevated concentrations of PBDEs in humans have been observed in Australia, no data is available on other BFRs such as HBCD. This study aimed to provide background HBCD concentrations from a representative sample of the Australian population and to assess temporal trends of HBCD and compare with PBDE concentrations over a 16 year period. Samples of human milk collected in Australia from 1993 to 2009, primarily from primiparae mothers were combined into 12 pools from 1993 (2 pools); 2001; 2002/2003 (4 pools); 2003/2004; 2006; 2007/2008 (2 pools); and 2009. Concentrations of ∑HBCD ranged from not quantified (nq) to 19 ng g(-1)lipid while α-HBCD and γ-HBCD ranged from nq to 10 ng g(-1)lipid and nq to 9.2 ng g(-1)lipid. β-HBCD was detected in only one sample at 3.6 ng g(-1)lipid while ∑(4)PBDE ranged from 2.5 to 15.8 ng g(-1)lipid. No temporal trend was apparent in HBCD concentrations in human milk collected in Australia from 1993 to 2009. In comparison, PBDE concentrations in human milk show a peak around 2002/03 (mean ∑(4)PBDEs=9.6 ng g(-1)lipid) and 2003/04 (12.4 ng g(-1)lipid) followed by a decrease in 2007/08 (2.7 ng g(-1)lipid) and 2009 (2.6 ng g(-1)lipid). In human blood serum samples collected from the Australian population, PBDE concentrations did not vary greatly (p=0.441) from 2002/03 to 2008/09. Continued monitoring including both human milk and serum for HBCD and PBDEs is required to observe trends in human body burden of HBCD and PBDEs body burden following changes to usage.     

Radiolytic decomposition of multi-class surfactants and their biotransformation products in sewage treatment plant effluents

Electron beam irradiation (EBI), as one of the most efficient advanced oxidation processes, was applied to the treatment of sewage treatment plant (STP) effluent, with the objective of evaluating the effectiveness of radiolytic decomposition of multi-class surfactants. Target compounds, included several high-volume surfactant groups, such as alkylphenol ethoxylates (APEOs) and their biotransformation products, linear alkylbenzene sulfonates (LAS), alkyl sulfates (AS), alkylether sulfates (AES), coconut diethanol amides (CDEA), alcohol ethoxylates (AEO) and polyethylene glycols (PEGs). EBI treatment of STP effluent (total concentration of APEO-derived compounds 265mugl(-1), being APE(2)C the most abundant by-degradation products) resulted in efficient decomposition of all alkylphenolic compounds; elimination of 94% longer ethoxy chain nonylphenol ethoxylates (NPEO, n(EO)=3-15) was obtained when 3kGy were applied. Slightly less efficient decomposition of short ethoxy chain oligomers (NPEO(1) and NPEO(2)) was observed, resulting in disappearance of about 80% of the initially present compounds. LC-MS analysis of treated wastewater suggested that the mechanism of EBI degradation of APEOs is a combination of two parallel pathways: a progressive shortening and oxidation of the ethoxy chain, which resulted in a formation of short ethoxy chain oligomers and APECs and central fission that resulted in formation of PEGs. Decomposition of APECs at 1kGy initially yielded APs, which were subsequently eliminated applying higher radiation doses. With a radiation dose of 2kGy about 95% of NPE(1)C and 97% of NPE(2)C were decomposed. Similar elimination rates were obtained for octylphenolic compounds. Radiolytic treatment applied was also very effective in removing PEGs formed as by-products from APEO degradation, as well as in decomposing other surfactants, such as linear LAS, AS and AES.     

Human exposure to polychlorinated naphthalenes through the consumption of edible marine species

The concentrations of polychlorinated naphthalenes (PCNs) were determined in samples of 14 edible marine species (sardine, tuna, anchovy, mackerel, swordfish, salmon, hake, red mullet, sole, cuttlefish, squid, clam, mussel and shrimp), which are widely consumed by the population of Catalonia, Spain. The daily intake of PCNs associated with this consumption was also determined. A total of 42 composite samples were analyzed by HRGC/HRMS. The highest PCN levels (ng/kg of fresh weight) were found in salmon (227) followed by mackerel (95) and red mullet (68), while the lowest levels of total PCNs corresponded to shrimp (4.9) and cuttlefish (2.7). With the exception of cephalopods and shellfish species, in which tetra-CN was the predominant homologue, penta-CN (60%) was the predominant contributor to total PCNs. For a standard male adult, PCN intake through the consumption of edible marine species was 1.53 ng/day. The highest contributions to this intake (ng/day) corresponded to salmon (0.41), sole (0.28) and tuna (0.24). Concerning health risks, species-specific TEFs such as those reported by WHO and NATO for PCDD/Fs and dioxin-like PCBs are not currently available for PCN congeners. Although in general terms the results of the present study do not seem to suggest specific risks derived from exposure to PCNs through fish and seafood consumption, to establish the contribution of individual PCN congeners to total TEQ is clearly necessary for the assessment of human health risks.     

Seasonal trends of atmospheric nitrogen dioxide and sulfur dioxide over North Santa Clara, Cuba

Atmospheric nitrogen dioxide (NO₂) and sulfur dioxide (SO₂) levels were monitored simultaneously by means of Radiello passive samplers at six sites of Santa Clara city, Cuba, in the cold and the warm seasons in 2010. The dissolved ionic forms of NO₂ and SO₂ as nitrate and sulfite plus sulfate, respectively, were determined by means of ion chromatography. Analysis of NO₂ as nitrite was also performed by UV–Vis spectrophotometry. For NO₂, significant t tests show good agreement between the results of IC and UV–Vis methods. The NO₂ and SO₂ concentrations peaked in the cold season, while their minimum levels were experienced in the warm season. The pollutant levels do not exceed the maximum allowable limit of the Cuban Standard 39:1999, i.e., 40 μg/m³ and 50 μg/m³ for NO₂ and SO₂, respectively. The lowest pollutant concentrations obtained in the warm season can be attributed to an increase in their removal via precipitation (scavenging) while to the decreased traffic density and industrial emission during the summer holidays (e.g., July and August).     

Particle-bound polycyclic aromatic hydrocarbons in an urban, industrial and rural area in the western Mediterranean

Particle-bound PAHs were measured at three sites in southeastern Spain (an urban background location, a suburban-industrial site in the vicinity of two cement plants and a rural area) in order to investigate the influence of the type of location on PAH concentrations. A clear influence of cement production on particulate PAH levels could not be established since for the urban background and suburban-industrial sites the average concentrations of total PAHs in the PM2.5 fraction were very similar (1.085 and 1.151 ng m(-3), respectively), with benzo[b+k]fluoranthene and chrysene as the predominant compounds. Diagnostic ratios, used to identify PAH emission sources, pointed to traffic as the main source of particulate PAH at both locations. As expected, PAH levels at the rural site were significantly lower (0.408 ng m(-3) in the PM10 fraction) due to increasing distance from the emission sources. PAH seasonal variations at the urban background and suburban-industrial sites were the same as reported in many previous studies. Average winter to summer ratios for total PAHs were 4.4 and 4.9 for the urban background and industrial sites, in that order. This seasonal cycle could be partially explained by the higher temperature and solar radiation during summer enhancing PAH evaporation from the particulate phase and PAH photochemical degradation, respectively. The study of PAH distribution between the fine and coarse fraction at the urban site revealed that on average around 80% of total PAHs were associated with fine particles.     

The Hungarian national climate change strategy: its principles, assignments, and a special case study on maize production

Efficient protection against global climate change requires international emission reduction measures. Before these ones are decided, the individual states should make arrangements within their own scope of authority for preventing and mitigating the adverse impacts of climate change already in progress as a consequence of carbon dioxide emissions done so far. In spring 2008 Hungary—among the very first ones in the international stage—passed a middle-term National Climate Change Strategy, which determines both the national tasks in order to reduce greenhouse gas emissions, and sectoral tasks of the adaptation to the ongoing climate change for the period of 2008–2025. As a concrete case study we investigated the possible impacts of the regional change in atmospheric carbon dioxide concentration, temperature and precipitation conditions of the Carpathian Basin on the cultivation conditions of maize, based on the downscaled IPCC 2007 scenarios. Temperatures of each scenarios increased significantly to basic run (1961–1990). This change suppressed the positive influence of elevated CO₂ on carbon assimilation. Serious depression may be waited during extreme hot days at Keszthely, Hungary.     

Identification of surfactant degradation products as toxic organic compounds present in sewage sludge

A cost-effective strategy combining chemical analysis and bioassays for the identification of polar toxic compounds in sewage sludge is reported. ToxAlert 100 bioluminescence inhibition assay was used in combination with chemical analysis involving extraction, clean-up, chromatographic separation and mass spectrometry detection. This methodology was applied to real samples of sludge from three wastewater treatment plants (WWTP) located in Catalonia (Spain) during a 3 month period. In the first step, sewage sludge was lyophilized, treated by sonication with a mixture of methanol and chloroform and finally cleaned up using a sequential solid phase extraction (SSPE) with an octadecylsilica cartridge (C18) in series with a polymeric Lichrolut EN cartridge (Lic EN). In the second step, the toxicity of each fraction of the sludge sample was investigated using the ToxAlert 100. The unequivocal identification and quantification of polar organic cytotoxic substances present in the fractionated extracts were determined by liquid chromatography-mass spectrometry (LC-MS). Major toxic compounds identified were: non-ionic polyethoxylated surfactants (nonylphenol polyethoxylates, alcohol polyethoxylates), their intermediates (polyethylene glycol polyethoxylated, nonylphenol carboxylates and polyethoxylated alcohol carboxylates), linear alkylbenzenesulfonates and heavy metals. The toxic response (in terms of bioluminescence inhibition using ToxAlert 100), defined by the 50% effective concentration (EC50), and the toxicity units (TU) for every standard non-ionic surfactant were calculated. The results provided the identification of polar cytotoxic compounds as well as the evaluation of their contribution to the total toxicity observed in sewage sludge.     

Comparison of effects of paraquat and methidation on enzyme activity and tissue necrosis of carp, following exposure to the pesticides singly or in combination

Under aquarium conditions, treatment with the herbicide paraquat (PQ) and with the insecticide methidation (MD) caused cell damage and stress in carp (Cyprinus carpio L.), as shown by increases in glutamate-dehydrogenase (GIDH, EC 1.4.1.2), glutamate-oxalacetate transaminase (GOT, EC 2.6.1.1) and lactate dehydrogenase (LDH, EC 1.1.1.27) activities and in blood sugar levels. PQ proved synergistic with MD in certain cases as regards the harmful effect exerted. On combined treatment, dilated extracellular spaces were visible by light microscope in the liver, while electronmicroscopic studies revealed signs indicative of cell autolysis in the same organ.