Uranium-238 and thorium-232 series concentrations in soil, radon-222 indoor and drinking water concentrations and dose assessment in the city of Aldama, Chihuahua, Mexico

High-resolution gamma spectrometry was used to determine the concentration of 40K, 238U and 232Th series in soil samples taken from areas surrounding the city of Aldama, in Chihuahua. Results of indoor air short-time sampling, with diffusion barrier charcoal detectors, revealed relatively high indoor radon levels, ranging from 29 to 422 Bq/m3; the radon concentrations detected exceeded 148 Bq/m3 in 76% of the homes tested. Additionally, liquid scintillation counting showed concentrations of radon in drinking water ranging from 4.3 to 42 kBq/m3. The high activity of 238U in soil found in some places may be a result of the uranium milling process performed 20 years ago in the area. High radon concentrations indoor and in water may be explained by assuming the presence of uranium-bearing rocks underneath of the city, similar to a felsic dike located near Aldama. The estimated annual effective dose of gamma radiation from the soil and radon inhalation was 3.83 mSv.     

Operation of a 27‐m3 biopile for the treatment of petroleum‐contaminated soil

Soil and groundwater contamination due to petroleum hydrocarbon spills is a frequent problem worldwide. In Mexico, even when programs oriented to the diminution of these undesirable events exist, in 2000, a total of 1,518 petroleum spills were reported. Exploration zones, refineries, and oil distribution and storage stations frequently are contaminated with total petroleum hydrocarbons (TPH); diesel fraction; gasoline fraction; benzene, toluene, ethyl benzene, and xylenes (BTEX); and polycyclic aromatic hydrocarbons (PAHs). Among the many methodologies available for the treatment of this kind of contaminated soil, bioremediation is the most favorable, because it is an efficient/low‐cost option that is environmentally friendly. This article discusses the capability of using a biopile to treat soils contaminated with about 40,000 mg/kg of TPH. Design and operation of a 27‐m³ biopile is described in this work, including microbiological and respirometric aspects. Parameters such as TPH, diesel fraction, BTEX, and PAHs considered by the U.S. Environmental Protection Agency were measured in biopile samples at 0, 2, 4, 6, 8, 10, and 22 weeks. A final average TPH concentration of 7,300 mg/kg was achieved in 22 weeks, a removal efficiency of 80 percent. © 2007 Wiley Periodicals, Inc.     

The liver but not the skin is the site for conversion of a red carotenoid in a passerine bird

Carotenoids may provide numerous health benefits and are also responsible for the integumentary coloration of many bird species. Despite their importance, many aspects of their metabolism are still poorly known, and even basic issues such as the anatomical sites of conversion remain controversial. Recent studies suggest that the transformation of carotenoid pigments takes place directly in the follicles during feather growth, even though the liver has been previously recognised as a storing organ for these pigments with a certain potential for conversion. In this context, we analysed the carotenoid profile of plasma, liver, skin and feathers of male Common Crossbills (Loxia curvirostra). Interestingly, the derivative feather pigment 3-hydroxy-echinenone was detected in the liver and in the bloodstream (i.e. the necessary vehicle to transport metabolites to colourful peripheral tissues). Our results demonstrate for the first time with empirical data that the liver may act as the main site for the synthesis of integumentary carotenoids. This finding contradicts previous assumptions and raises the question of possible inter-specific differences in the site of carotenoid conversion in birds.     

Assessment of heavy metals in the particulate matter of two Brazilian metropolitan areas by using <Emphasis Type="BoldItalic">Tillandsia usneoides</Emphasis> as atmospheric biomonitor

Purpose  

The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface.     

The fungal colonisation of rock-art caves: experimental evidence

The conservation of rock-art paintings in European caves is a matter of increasing interest. This derives from the bacterial colonisation of Altamira Cave, Spain and the recent fungal outbreak of Lascaux Cave, France—both included in the UNESCO World Heritage List. Here, we show direct evidence of a fungal colonisation of rock tablets in a testing system exposed in Altamira Cave. After 2 months, the tablets, previously sterilised, were heavily colonised by fungi and bacteria. Most fungi isolated were labelled as entomopathogens, while the bacteria were those regularly identified in the cave. Rock colonisation was probably promoted by the dissolved organic carbon supplied with the dripping and condensation waters and favoured by the displacement of aerosols towards the interior of the cave, which contributed to the dissemination of microorganisms. The role of arthropods in the dispersal of spores may also help in understanding fungal colonisation. This study evidences the fragility of rock-art caves and demonstrates that microorganisms can easily colonise bare rocks and materials introduced into the cavity.     

Digit ratios (2D:4D), secondary sexual characters and cell-mediated immunity in house sparrows <Emphasis Type="Italic">Passer domesticus</Emphasis>

Homeobox genes regulate development of digits, and it has been suggested that the ratio of length of second to length of fourth digit reflects such genetic effects in a sex-specific manner. We show that digit ratios in the sexually dichromatic house sparrow Passer domesticus differ between sexes, with males having higher ratios than females, and that individuals produce consistent ratios on the two feet. If Homeobox or other genes had pleiotropic effects on development of digits, behavior, and physiology of males and females, we would expect secondary sexual characters and immunity to be related to digit ratio in a sex-specific manner. The size of the visible part of the black badge in February (a secondary sexual character), but not total badge size, was positively correlated with digit ratios, suggesting that males with more male-like digit ratios had larger visible badges. Because of sex-specific effects of development on secondary sexual characters and immunity, we predicted sex-specific differences in immune response to be related to digit ratio. House sparrows with large digit ratios had weaker T cell-mediated immune response than individuals with small digit ratios, particularly in females, implying that females with more male-like digit ratios had weak immune responses. These findings are consistent with the hypothesis that early development, as reflected by digit ratios, and genetics affect the expression of adult characters that are supposedly strongly contributing to fitness.     

Environmental quality assessment combining sediment metal levels, biomarkers and macrobenthic communities: application to the óbidos coastal lagoon (Portugal)

Macroinvertebrate benthic communities are one of the key biological components considered for the assessment of benthic integrity in the context of the Water Framework Directive (WFD). However, under moderate contamination scenarios, the assessment of macrobenthic alterations at community level alone could be insufficient to discriminate the environmental quality of coastal and transitional waters. Keeping this in view, sediment quality of moderately contaminated sites in a coastal lagoon (óbidos lagoon, Portugal) was assessed by the combination of sediment metal levels, Carcinus maenas biomarkers (accumulated metals and oxidative stress responses) and macrobenthic communities. Two sites were selected in confined inner branches (BS and BB) and a third one in the middle lagoon (ML). The site BB presented slightly higher levels of metals in sediment but biological variables calculated for macrobenthic data were not significantly different between sites. The biotic index M-AMBI that is being applied to assess environmental quality of transitional waters in the scope of the WFD pointed either to high (site ML) or good quality status (BS and BB) in the selected sites. However, crabs from BB site presented significantly higher levels of Ni in hepatopancreas than those from ML and macrobenthic community structure was significantly different between BB and ML. Additionally, spatial differences were obtained for oxidative stress parameters suggesting that BB site presented stressors for crabs (higher GST and lower GSH_t at BB site). Factor analysis (PCA) integrating sediment contamination, biomarkers in crabs and macrobenthic data also distinguished BB site as the most environmentally disturbed. On the other hand, at ML site, some macrobenthic variables (equitability and polychaetes’ diversity) were found to be enhanced by current environmental conditions, suggesting the existence of a better sediment quality. Current results pointed to the usefulness of integrating macrobenthic community alterations with responses at organism level (bioaccumulation and biochemical endpoints) in order to increase the accuracy of environmental quality assessment in lagoon systems. Moreover, the application of different statistical methods was also found to be recommendable.