Effect of acute nitrogen dioxide exposure on the composition of fatty acid associated with phospholipids in alveolar lavage

In vivo exposure of rats to 10 ppm nitrogen dioxide (NO₂) for 12h caused changes in fatty acids composition of alveolar lavage phospholipids. Among the fatty acid species, the relative ratio of palmitic acid, myristic acid and palmitoleic acid increased significantly. While the relative ratio of stearic acid, oleic acid, linoleic acid and arachidonic acid decreased significantly. Both the increase in the incorporation of palmitic acid in phosphatidylcholine which would be released into the alveoli and the increase in the release of phosphatidylcholine into the alveoli may account for the changes in the fatty acid composition of the present findings.     

Leaching of heavy metals in acid mine drainage.

Acid mine drainage is one of the most serious environmental problems that the coal and metal mining industry is currently facing. The generation of low pH drainage enhances the dissolution of heavy metals in water. The samples used in this research originated from three pits at mine dumps. In a study reported in this paper, three types of tests; namely static test, kinetic test and column test were conducted to estimate acid generation and acid neutralization reaction rates, and to predict the solubility of metals and their release rates. Static test showed that all samples had a pH of net acid generation (NAG pH) <4, a net acid producing potential (NAPP) >10 kg H2SO4tonne(-1), and a S-content >3%, which can be classified as a high acid-forming capacity. Simulated runoff in the column tests was equivalent to 5-year average rainfall in Indonesia, the resultant leachates showed acidic behaviour (pH < 3.5). Based on the results, it was found that high mobilization of heavy metals (Cr, Cu, Zn, Cd and Pb) takes place under strong acidic conditions (pH approximately equal 2).     

Voltammetric response of ferroceneboronic acid to diol and phenolic compounds as possible pollutants

A voltammetric determination of possible organic pollutants such as diol and phenolic compounds in water was studied using ferroceneboronic acid (FBA) as a redox-active marker. A cyclic voltammogram of FBA exhibited a pair of oxidation and reduction peaks at 230 and 170 mV at pH 7.0, respectively, while another pair of redox peaks was observed in the presence of diol or phenolic compounds tested. The results were rationalized based on the formation of boronate esters of FBA with the added compounds. The changes in the redox peak currents were dependent on the concentration of the additives, suggesting a usefulness of FBA in the electrochemical determination of these compounds in water.     

Potential ammonia emission from flag leaves of paddy rice (Oryza sativa L. cv. Koshihikari)

The present study aimed to investigate the potential ammonia (NH₃) emission from flag leaves of paddy rice (Oryza sativa L. cv. Koshihikari). The study was conducted at a paddy field in central Japan that was designed as a free-air CO₂ enrichment (FACE) facility for paddy rice. A dynamic chamber method was used to measure the potential NH₃ emissions. The air concentrations of NH₃ at two heights (2 and 6 m from the ground surface) were measured using a filter-pack method, and the exchange fluxes of NH₃ of the whole paddy field were calculated using a gradient method. The flag leaves showed potential NH₃ emissions of 25-38 ng N cm⁻² h⁻¹ in the daytime from the heading to the maturity stages, and they showed potentials of approximately 22 ng N cm⁻² h⁻¹, even in the nighttime, at the heading and mid-ripening stages. The exchange fluxes of NH₃ of the whole paddy field in the daytime were net emissions of 0.9-3.9 g N ha⁻¹ h⁻¹ whereas the exchange fluxes of NH₃ in the nighttime were approximately zero.     

Field Survey of Trans-boundary Air Pollution with High Time Resolution at Coastal Sites on the Sea of Japan during Winter in Japan}

An intensive field survey, with 6-h measurement intervals, of concentrations of chemical species in particulate matter and gaseous compounds was carried out at coastal sites on the Sea of Japan during winter. The concentration variation of SO₂(g) and HNO₃(g) were well correlated, whereas the NH₃(g) concentration variation had no correlation with those of SO₂(g) and HNO₃(g). The NH₄ ⁺ (p)/non-sea-salt- (nss-)SO₄ ^{2 −}(p) ratio in particulate matter was mainly affected by the location of the sampling site. One or more concentration peaks of nss-Ca^{2 +} for survey period were observed. Backward trajectories analyses for the highest nss-Ca^{2 +} concentration peaks showed some inconsistency in pathways. We consider that insufficient mixing of the atmosphere and/or insufficient time for the transported air pollutants to react with those discharged locally are the most likely explanations for the discrepancies between the measured products [HNO₃][NH₃] and the calculated values.     

Land-Cover Changes and Its Impacts on Ecological Variables in the Headwaters Area of the Yangtze River, China

Land cover changes affect ecological landscape spatial pattern, and evolving landscape patterns inevitably cause an evolution in ecosystem functionality. Various ecological landscape variables, such as biological productivity (plant biomass and stock capacity), soil nutrients (organic matter and N content) and water source conservation capacity are identified as landscape function characteristics. A quantitative method and digital model for analyzing evolving landscape functionality in the headwaters areas of the Yangtze River, China were devised. In the period 1986–2000, patch transitions of the region's evolving landscapes have been predominantly characterized by alpine cold swamp meadow, with the highest coverage tending to be steppified meadow or steppe, and desertification landscape such as sand and bare rock land expansion. As the result of such changes, alpine swamp areas decreased by 3.08 × 10³ km² and the alpine cold sparse steppe and bare rock and soil land increased by 6.48 × 10³ km² and 5.82 × 10³ km², respectively. Consequently, the grass biomass production decreased by 2627.15 Gg, of which alpine cold swamp meadows accounted for 55.9% of this loss. The overall stock capacity of the headwaters area of the Yangtze River decreased by 920.64 thousand sheep units, of which 502.02 thousand sheep units decreased in ACS (Alpine cold swamp) meadow transition. Soil organic matter and N contents decreased significantly in most alpine cold meadow and swamp meadow landscape patches. From 1986 to 2000 the total losses of soil organic matter and total N in the entire headwaters region amounted to 150.2 Gkg and 7.67 Gkg. Meanwhile, the landscape soil water capacity declined by 935.9 Mm³, of which 83.9% occurred in the ACS meadow transition. In the headwater area of the Yangtze River, the complex transition of landscape resulted in sharp eco-environmental deterioration. The main indication for these changes involved the intensity of the climate in this region is becoming drier and warmer, resulting in a gradual degradation of the permafrost.     

Effects of parabens on apoptosis induced by serum-free medium

Alkyl esters of p-hydroxybenzoic acids (parabens), an endocrine disrupter, are used as preservatives in cosmetics and foods. In this study, to understand the relationship between parabens and differentiation in infants, the effects of parabens on apoptosis induced by serum deprivation in PC12 cells were investigated. In addition, apoptosis-related factors were assayed. As results, a tendency toward enhancement of apoptosis was observed in the cells cultured in the serum-free medium with methylparaben, and this tendency was suggested to be related to the contents of BAD, a pro-apoptotic protein. Butylparaben did not show any tendency to enhance apoptosis.     

Some mineral constituents of Parasol Mushroom (Macrolepiota procera)

This article reports background concentrations of Ag, Ba, Cd, Co, Cr, Cs, Cu, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Se, Tl, V and Zn in caps and stalks of M. procera collected from four spatially distant sites across Poland. The elements were determined using inductively coupled plasma-mass spectrometry (ICP-MS), hydride generation atomic absorption spectrometry (HG-AAS) or a cold vapor atomic absorption spectrometry (CV-AAS). Copper, zinc, rubidium, selenium, chromium and cobalt were the most abundant amongst elements determined in this mushroom. Some elements (Cu, Zn, Rb, Se, Pb, Hg, Cd, Mo) occurred at greater concentrations in the caps than stalks of M. procera and some (Ag, Ba, Sr, V, Tl) dominated in the stalks, while for some other this proportion was similar or varied (Mn, Cr, Co, Ga, Sb, Cs) depending on the sampling site. For elements such as copper, zinc, rubidium as well as selenium some spatial similarity in distribution and/or concentration values both in caps and stalks was noted. Cadmium and lead content in caps of M. procera was usually below the European Union tolerance limit value of 2.0 and 3.0 microg/g dw set for cultivated mushrooms, respectively. These two toxic metals have been found in elevated concentration in M. procera from unpolluted stands outside of Poland as reported by some authors, which implies the possibility of relatively high background levels in this species.     

Specific accumulation of arsenic compounds in green turtles (Chelonia mydas) and hawksbill turtles (Eretmochelys imbricata) from Ishigaki Island, Japan

Concentrations of total arsenic (As) and individual compounds were determined in green and hawksbill turtles from Ishigaki Island, Japan. In both species, total As concentrations were highest in muscle among the tissues. Arsenobetaine was a major compound in most tissues of both turtles. High concentrations of trimethylarsine oxide were detected in hawksbill turtles. A significant negative correlation between standard carapace length (SCL), an indicator of age, and total As levels in green turtles was found. In contrast, the levels increased with SCL of hawksbill turtles. Shifts in feeding habitats with growth may account for such a growth-dependent accumulation of As. Although concentrations of As in marine sponges, the major food of hawksbill turtles are not high compared to those in algae eaten by green turtles, As concentrations in hawksbill turtles were higher than those in green turtles, indicating that hawksbill turtles may have a specific accumulation mechanism for As.