Bottled-Water Quality in Metropolitan Mexico City

Bacteriological and physico-chemical parameters of 265 samples from 39 brands sold in 5-gallon plastic and glass bottles and 2-5 L plastic containers were analyzed to determine the quality of bottled water distributed in Mexico City. Tests included fecal and total coliform counts, alkalinity, total hardness, chloride, calcium and magnesium concentrations, pH and conductivity. Correlation and cluster analyses and ANOVA were carried out, and a comparison made of the averages with the maximum permissible levels established in the Official Mexican Norms. Concerning the investigated parameters no differences (p > 0.05) between the brands were found. Physico-chemical parameters were studied and all the samples were within the permissible limits. Most samples taken from the 5-gallon containers exceeded the maximum bacteriological limits. It was concluded that the bacteriological quality of the brands studied was extremely variable. Appropriate sanitary measures, should be established to control this aspect.     

Aluminum speciation in the bulk and rhizospheric soil solution of the species colonizing an abandoned copper mine in Galicia (NW Spain)

Purpose  

The present study was carried out to identify and quantify the aluminum species present in the bulk and rhizospheric soil solution of the spontaneous vegetation colonizing the dump (Calluna vulgaris, Erica cinerea) and slope (C. vulgaris, E. cinerea, Salix atrocinerea) of an abandoned Cu mine in Touro (Galicia, NW Spain).     

Fluorine immission to acid soil in the vicinity of an aluminium smelter in Galicia (NW Spain) and its influence on aluminium dynamics

Purpose

The aluminium smelter located in the northern coast of Galicia (NW Spain) is a source of fluoride pollution. Previous papers Gago et al. (Commun Soil Sci Plant Anal 32:2503–2517, 2001, Fluoride 35:110–121, 2002) have identified an area of 3-km radius around the factory being affected by fluoride emissions. This study aims to investigate the influence of fluoride emissions on fluorine concentration and speciation as well as on aluminium speciation in soils in the vicinity of the smelter.

Materials and methods

PVC cylinders containing soil material from the A horizon of an unpolluted forest soil, similar to that in the vicinity of the factory, were placed within the A horizon of soils surrounding the smelter. The cylinders were placed at various distances (up to 3 km) from the factory in the direction of predominant winds. The PVC columns were removed after 6 months, and the soil material inside was divided into two slices (0–10 and 10–20 cm) and analysed for pH, total and available fluorine, exchangeable cations, effective cation exchange capacity (CEC) and oxalate-extracted aluminium. The soil solution was mimicked by aqueous extracts and analysed for pH, electrical conductivity, Ca, Mg, Na, K, total and free fluorine, total Al, acid-soluble Al, non-labile Al, labile Al and labile Al species.

Results and discussion

In the area closest to the factory (0.5 km), total and available fluorine in the upmost 10 cm soil increased by twofold and eightfold, respectively, while soluble fluoride increased by fourfold. Increases were also observed in exchangeable Ca, Mg, Al and CEC. Noncrystalline Al increased significantly at any distance from the smelter. Fluorine, pH, sulphate, aluminium and organic matter increased in the soil solution of surface (<10 cm) samples closest to the factory. Monomeric Al-organic matter complexes prevailed in the liquid phase at 0.5–1 km from the factory whereas inorganic Al complexes did at distances over 1 km. Among the inorganic Al complexes, fluoride complexes prevailed at distances less than 1 km and hydroxylated complexes at distances greater than 1 km. Al³⁺ concentration was always very low.

Conclusions

Emissions from an aluminium smelter led to increased concentrations of fluorine and various forms of aluminium in the nearby soil. These emissions mobilised aluminium, organic matter and probably sulphate from the soil. In the closest neighbourhood of the smelter, it was found that most soluble aluminium was bound to organic matter, hence having low toxicity, while at distances farther than 1 km Al-F and Al-OH complexes prevailed.     

Effect of industrial dehydration on the soluble carbohydrates and dietary fiber fractions in legumes

The effects of soaking, cooking, and industrial dehydration treatments on soluble carbohydrates, including raffinose family oligosaccharides (RFOs), and also on total dietary fiber (TDF), insoluble dietary fiber (IDF), and soluble (SDF) dietary fiber fractions were studied in legumes (lentil and chickpea). Ciceritol and stachyose were the main alpha-galactosides for chickpea and lentil, respectively. The processing involved a drastic reduction of soluble carbohydrates of these legumes, 85% in the case of lentil and 57% in the case of chickpea. The processed legume flours presented low residual levels of alpha-galactosides, which are advisable for people with digestive problems. Processing of legumes involved changes in dietary fiber fractions. A general increase of IDF (27-36%) due to the increase of glucose and Klason lignin was observed. However, a different behavior of SDF was exhibited during thermal dehydration, this fraction increasing in the case of chickpea (32%) and decreasing in the case of lentil (27%). This is probably caused by the different structures and compositions of the cell wall networks of the legumes.     

Ozone Biomonitoring with Bel-W3 Tobacco Plants in the City of Valencia (Spain)

A biomonitoring study using the ozone-sensitive bioindicator plant Nicotiana tabacum cv. Bel-W3 was conducted in the city of Valencia (eastern Spain) and surrounding areas in 2002. Plants were exposed to ambient air at seven sites, including four traffic-exposed urban sites, a large urban garden and a suburban and a rural station, for six consecutive 2-week periods using highly standardised methods. Foliar injury was registered at all stations in at least one of the exposure periods. The urban stations submitted to intense traffic showed lower ozone injury than the less traffic-exposed stations. Strong changes in the intensity of ozone injury were observed for the different exposure periods. Leaf injury was significantly related to both mean ozone values (24 and 12 h means) and cumulative exposure indices (AOT20, AOT40). However, correlation strength was moderate (r _s?=?0.39 to 0.58), suggesting that the plant response to ozone was modified by environmental factors. The use of sensitive bioindicators like tobacco Bel-W3 in cities provides complementary information to that of continuously operating air quality monitors, as the impact of ambient ozone levels is directly measured.     

Calcium fertilizers induce soil suppressiveness to <Emphasis Type="BoldItalic">Phytophthora cinnamomi</Emphasis> root rot of <Emphasis Type="BoldItalic">Quercus ilex</Emphasis>

Based on the observation that the root disease caused by P. cinnamomi on Q. ilex has a low incidence and severity in soils with medium-high Ca²⁺ content, we studied the ability of Ca²⁺ fertilizers to induce soil suppressiveness to the pathogen. Studies on cultures of P. cinnamomi exposed to different Ca²⁺ fertilizers in vitro showed significant inhibition of sporangial, chlamydospore and zoospore production at millimolar concentrations while mycelial growth was mainly unaffected. Experiments performed with artificially infested soil showed that some Ca²⁺ fertilizers induce a significant decrease on chlamydospore viability. Additionally, greenhouse experiments using artificially infested soils showed a significant reduction of foliar and root symptom severities in Holm oak seedlings growing in soils amended with Ca²⁺ fertilizers. We suggest that limestone amendments in oak rangelands could enhance the suppressiveness of soils to P. cinnamomi, and it is likely that the inhibition of sporangial production was the main mechanism involved.     

Photolysis of pirimicarb in water under natural and simulated sunlight conditions

The photostability of pirimicarb, (2-dimethylamino-5,6-dimethylpyrimidin-4-yl dimethylcarbamate) in aqueous media, under natural and artificial sunlight irradiation conditions, is reported. The pH of the irradiated solutions remained constant during degradation time. The photodegradation mechanism seemed to be similar under both conditions, but the half-life was found to be about three times longer under natural than under artificial conditions. Four main photo-products ( 1 , 2 , 3 and 4 ) were isolated and identified by spectroscopic methods. It is proposed that a common photodegradation pathway exists for pirimicarb under both irradiation conditions. The results obtained from the photodegradation of pirimicarb and of its four main products isolated on solid phase permit the construction of a possible photodegradation pathway. Photoproduct 4 (2-methyl-formylamino-5,6-dimethyl-4-hydroxypyrimidine) is here described for the first time.     

Isolation of amoebae of the genera Naegleria and Acanthamoeba from public fountains in Galicia (N.W. Spain)

Tests for free-living amoebae in water from 11 public fountains in Galicia were conducted at two seasons of the year, winter and summer. Only one fountain gave a negative result for the presence of amoebae in both samples. Twenty five strains were isolated, 14 belonging to the genus Acanthamoeba and 10 to the genus Naegleria. The Acanthamoeba strains were made up of the species A. polyphaga, A. quina, A. castellanii and A. paradivionensis. No relation was found between temperature, presence of free chlorine in the water and whether the water was drinkable and the presence or absence of amoebae, nor with the number of strains present in the water samples. The pathogenic capacity of the strains isolated from the genera Naegleria and Acanthamoeba was tested in vivo. It was found that of the 22 strains that would grow at 37 °C, 4 (3 strains of Acanthamoeba and 1 of Naegleria) caused the death of a statistically significant number of mice that had been inoculated intracerebrally, and the presence of amoebae was confirmed in the brains of all the animals inoculated. Intranasal inoculation caused less mice deaths than intracerebral inoculation, and less organs were found containing amoebae.     

Approaches to spirit aroma: contribution of some aromatic compounds to the primary aroma in samples of orujo spirits

Terpenes and C(13) norisoprenoids are among the most important aromatic compounds found in a volatile and nonvolatile form in grapes. Aromatic typicity of a spirit could be attributed to these compounds despite the very important presence of volatile compounds produced during alcoholic fermentation. In this study, following a solid phase extraction stage, the determination of the varietal aromatic compounds by gas chromatography was performed on 15 samples of Galician orujo spirits. The results show that significant differences (p < 0.05) exist in the concentrations of varietal aromatic compounds in Galician spirits obtained from different varieties of grapes. alpha-Ionona is the varietal aromatic compound that is most likely to contribute to the aroma of all of the spirits studied. The spirits from Catalan Roxo are the most aromatic, with floral and fruity nuances, while the spirits from Godello were the less aromatic group as far as the varietal compounds studied are concerned. Spirits from Mencia and Treixadura show a similar profile, but the former has a more intensive aroma due to beta-pinene, citronellol, and alpha-ionone. Albari?o spirits stand out because of their profile that is marked by the contributions of eugenol and linalool.