Influence of Sulfur Dioxide and Hydrogen Fluoride as a Mix or Reciprocal Exposure on Citrus Growth and Development

The influence of exposure to mixtures of SO₂ and HF on Koethen sweet orange and mixtures and alternate exposure to these gases on Satsuma mandarin were tested using a rotating fumigation greenhouse. Effects of HF-SO₂ mixtures on linear growth and leaf area of Koethen orange were additive, not synergistic. No necrosis was observed on Koethen oranges exposed to HF, SO₂, or a mixture of HF and SO₂. Effects of the mixture on chlorosis of Satsuma mandarin foliage was also not synergistic. No significant difference in linear growth of Satsuma mandarin was found among all treatments. Alternate exposure to SO₂ followed by HF produced no synergistic injury to Satsuma mandarin. Satsuma mandarin appeared more sensitive than Koethen orange to HF, SO₂, and mixtures of these two gases using degree of chlorosis and leaf abscission as the criteria of sensitivity. If iinear growth and leaf area were the principal criteria considered, Koethen orange would appear more sensitive.     

Online measurements of low-volatile organic chlorine for dioxin monitoring at municipal waste incinerators

In this study, an automatic sampling device and an analysis device have been developed for the measurement of low-volatile organic chlorine (LVOCl) in flue gas. The concentrations of dioxins (polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls) have been estimated by online measurements of LVOCl at a municipal solid waste incinerator (MSWI) using these devices. The LVOCl concentration at the outlet of the selective catalyst reactor (SCR) of the MSWI increased momentarily up to 95 μg Cl m⁻³ during the startup period of the MSWI; subsequently, it gradually decreased to less than 1.0 μg Cl m⁻³ after 50 h from the start of waste feeding. The concentration of toxic equivalent quantity (TEQ)-Dioxins at the SCR outlet had a linear positive relationship with the LVOCl concentrations. Moreover, the level of TEQ-Dioxins concentration can be estimated by using this relationship with LVOCl. From our results, since the LVOCl concentrations in a flue gas can thus be automatically analyzed every hour by online measurements, the operators of an MSWI would be able to monitor approximate TEQ-Dioxin emissions on a daily basis.     

Development of active and diffusive sampling methods for determination of 3-methoxybutyl acetate in workplace air

Monitoring of the workplace concentration of 3-methoxybutyl acetate (MBA), which is used in printer's ink and thinner for screen-printing and as an organic solvent to dissolve various resins, is important for health reasons. An active and a diffusive sampling method, using a gas chromatograph equipped with a flame ionization detector, were developed for the determination of MBA in workplace air. For the active sampling method using an activated charcoal tube, the overall desorption efficiency was 101%, the overall recovery was 104%, and the recovery after 8 days of storage in a refrigerator was more than 90%. For the diffusive sampling method using the 3M 3500 organic vapor monitor, the MBA sampling rate was 19.89 cm(3) min(-1). The linear range was from 0.01 to 96.00 microg ml(-1), with a correlation coefficient of 0.999, and the detection limits of the active and diffusive samplers were 0.04 and 0.07 microg sample(-1), respectively. The geometric mean of stationary sampling and personal sampling in a screen-printing factory were 12.61 and 16.52 ppm, respectively, indicating that both methods can be used to measure MBA in workplace air.     

Gas chromatography�Cmass spectrometry for metabolite profiling of Japanese medaka (Oryzias latipes) juveniles exposed to malathion

Purpose

We evaluate malathion toxicity to Japanese medaka (Oryzias latipes) juveniles by using a mass spectrometry combined with gas chromatography (GC/MS) metabolomics approach.

Methods

Medaka were exposed to low (L) and high (H) concentrations (nominally 20 and 2,000 ??g/L, respectively) of water-borne malathion. Metabolites were extracted from the fish, derivatized, and analyzed by GC/MS. Identified metabolites were subjected to one-way analysis of variance and principal component analysis (PCA). We examined the variations in the amounts of the metabolites during the exposure period.

Results and discussion

At 24 h, control, L, and H groups were separated along PC1, suggesting that the effects of malathion depended on exposure concentration. The PCA results at 96 h suggest that the metabolite profiles variations of the L and H groups differed, and thus that the effects of malathion in groups differed. At 24 h, the amounts of amino acids in both exposed groups were lower than the control group amounts, perhaps owing to accelerated protein synthesis. At 96 h, the amounts of almost all the amino acids increased in the L group but decreased in the H group relative to the control group amounts, suggesting the proteolysis occurred in the L group while protein synthesis continued in the H group, that the high malathion exposure affected the fish. In addition, at 96 h, gluconeogenesis may have been induced in the L group but not in H group.

Conclusions

Malathion exposure may have altered the balance between protein synthesis and degradation and induced gluconeogenesis in medaka. Our results suggest that metabolomics will be useful for comprehensive evaluation of toxicity.     

Monitoring of PAHs and alkylated PAHs in aquatic organisms after 1 month from the Solar I oil spill off the coast of Guimaras Island, Philippines

Following the oil spill accident of the Solar I tanker in 2006 off the coast of Guimaras Island in the Philippines, polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in some aquatic organisms were investigated at Luzaran in Guimaras and Taklong Islands, which were heavily polluted with spilled oil, immediately and 1 month after the accident. The concentrations of total PAHs were 11.9–52.3 ng/g dry weight in fish. Meanwhile, total PAH concentrations in shellfish were 38.0–3,102 ng/g dry weight in Luzaran and 128–236 ng/g dry weight in Taklong. Pyrene, phenanthrene, and fluoranthene were dominant in most fish and chrysene in all shellfish. Significantly higher concentrations of all alkylated homologs were detected in shellfish than in fish. These differences had two possible causes, that is, the differences between fish and shellfish could be attributed to the uptake routes and/or their metabolizing abilities.     

Assessment of the Effectiveness of Protected Areas Management in Iran: Case Study in Khojir National Park

The requirement to assess the management effectiveness (ME) in protected areas (PAs) is increasing around the world to help improve management and accountability. An evaluation of ME for Khojir National Park (KNP), one of the Iran’s oldest PAs, was conducted using a multi-method approach that consisted of structured interviews, open interviews, and site visits. This was the first ME evaluation in Iran. The structured interview was based on the management effectiveness tracking tool methodology. KNP received an average score of 43 %, which is lower than the global average, illustrating that its general management was in the low-intermediate level. The indices of legal status, resource inventory, planning for land and water use, regulations, and objectives received the highest average scores, whereas education and awareness, community co-management, regular work plan, boundary demarcation, visitor facilities, budget sources, staff training, protection systems, and management plan received the lowest ones. The management system of KNP was generally established, but many problems of the management still need to be resolved. To improve ME, some countermeasures should be taken, such as increasing funding, strengthening capacity building, planning, and adaptive management, and implementing community participation.     

Uptake and distribution of 90Sr and stable Sr in rice plants

The stable Sr content in the aboveground parts of rice plants at various growth stages, and the distributions of 90Sr and stable Sr in rice plant components, such as polished rice, rice bran, hull, straw and root, at harvest time, were determined. The total Sr content in the aboveground rice plants was dependent on the growth stage and followed the sigmoidal shape of the growth curve. The concentration of 90Sr among the different components of rice plants varied within two orders of magnitude, whereas the 90Sr/Sr concentration ratio had a constant value. Therefore, the translocation rate of 90Sr in rice plants had similar values to that of stable Sr. However, the 90Sr/Sr concentration ratio for the rice plants was different for each study site. Only 0.6% of the total Sr was found in polished rice, while more than 99% was found in the non-edible components, of which 87% was present in the straw. These findings suggest that 90Sr in the non-edible parts could have been transferred to humans through the soil-plant system and/or feed-livestock pathway. The soil-to-plant transfer factor of 90Sr in polished rice was 0.0021 +/- 0.00007, which was two orders of magnitude lower than that in the straw. The percentage of 90Sr removed from the upper soil layer to the aboveground biomass of rice plants at harvest time was calculated as 0.094%. It is possible that approximately 0.1% of the total 90Sr content in the surface soil layer is removed from the soil-plant system by human activities every year.     

Concentration and specific activity of fallout 137Cs in extracted and particle-size fractions of cultivated soils

Fallout (137)Cs and stable Cs in soils were separated with two extractants (1M CH(3)COONH(4) solution and 0.8M CH(3)COONH(4) in 5% HNO(3) solution after H(2)O(2) oxidization). The residue remaining after removal of the oxidizable organic-bound fraction was separated into the particle-size fractions including clay, silt, fine sand and coarse sand with a sieving and sedimentation method. Then, the concentrations of (137)Cs and stable Cs in the extracted fractions and the particle-size fractions were determined. The (137)Cs contents in the exchangeable and organic-bound fractions in the soil were approximately 10 and 20%, respectively. The (137)Cs content in the strongly bound fraction was about 70%, and the concentration of (137)Cs in the clay was the richest among the particle-size fractions. The specific activity of (137)Cs (concentration ratio of fallout (137)Cs/stable Cs) decreased in the order exchangeable, organic-bound and strongly bound fractions. The data suggest that equilibrium between (137)Cs and stable Cs was not reached among those fractions, even though most of the (137)Cs that had been deposited on the soil was derived from fallout weapons tests that occurred several decades ago. The concentration of (137)Cs among the particle-size fractions in each soil was different, whereas the specific activity of (137)Cs in the particle-size fractions had a relatively similar value.