Increase in membrane thickness during development compensates for eggshell thinning due to calcium uptake by the embryo in falcons

We compared membrane thickness of fully developed eggs with those of non-developed eggs in different endangered falcon taxa. To our knowledge, membrane thickness variation during development has never been examined before in falcons or any other wild bird. Yet, the egg membrane constitutes an important protective barrier for the developing embryo. Because eggshell thinning is a general process that occurs during bird development, caused by calcium uptake by the embryo, eggs are expected to be less protected and vulnerable to breakage near the end of development. Thus, egg membranes could play an important protective role in the later stages of development by getting relatively thicker. We used linear mixed models to explore the variation in membrane thickness (n = 378 eggs) in relation to developmental stage, taxon, female age, mass and identity (73 females), egg-laying sequence (105 clutches) and the study zone. Our results are consistent with the prediction that egg membranes are thicker in fully developed eggs than in non-developed eggs, suggesting that the increase in membrane thickness during development may compensate for eggshell thinning. In addition, our data shown that thicker membranes are associated with larger, heavier and relatively wider eggs, as well as with eggs that had thinner eggshells. Egg-laying sequence, female age and the study zone did not explain the observed variation of membrane thickness in the falcon taxa studied. As we provide quantitative data on membrane thickness variation during development in falcons not subjected to contamination or food limitation (i.e. bred under captive conditions), our data may be used as a reference for studies on eggs from natural populations. Considering the large variation in membrane thickness and the multiple factors affecting on it and its importance in the protection of the embryo, we encourage other researchers to include measurements on membranes in studies exploring eggshell thickness variation.     

Mandating interlocks for fully revoked offenders: the New Mexico experience

OBJECTIVE: In New Mexico, between July 1999 and December 2002, the installation of an ignition interlock was an optional judicial sanction for second and third driving-while-impaired (DWI) offenders. This is a study of the recidivism of 437 offenders who were convicted and installed interlocks for an average of 322 days during that period. METHODS: The comparison group was a stratified random sample (N = 12,554) of the 20,949 offenders who were convicted during the same period but did not install interlocks. DWI arrest and conviction data for all study participants were received from the Motor Vehicle Department's Citation Tracking System. RESULTS: Only 11 (2.5%) of the interlock offender group were rearrested for DWI while interlocks were installed, whereas 1,017 (8.1%) of the comparison group were rearrested during an equivalent 322-day period. Survival graphs and Cox proportional hazard regression analyses were used to compare the interlock and noninterlock groups during installation, after installation, and for the entire period up to December 2004. Results indicate a reduction in recidivism of 65% during installation. After removal, there was no significant difference in recidivism rates in a 3-year follow-up period. Following all offenders for 4 years, including both the period while the interlock was installed and the period after its removal, indicates that the difference in recidivism achieved during installation, though not increased, is maintained, so at the end of 4 years, interlock users still have lower total recidivism than nonusers. CONCLUSIONS: The magnitude of interlock effectiveness reported here is similar to those in other published studies with comparable samples.     

Metal-contaminated soil remediation by using sludges of the marble industry: toxicological evaluation

The major risks due to metal pollution of sediments consist of leaching to groundwater and potential toxicity to animals and/or plants. The objective of this study was to evaluate by means of an ecotoxicological approach the effects of the addition of cutting marble sludges on the mobile metal fraction of sediments polluted with heavy metals. The study was carried out on two sediments derived from mining activities in Portman Bay (SE, Spain) polluted by heavy metals. These sediments were mixed with sludges left after the cutting of marble. The results obtained by leaching experiments showed that the addition of marble cutting sludge, consisting mainly of carbonates, to a heavy-metal polluted sediment produces a decrease of available metal forms. The carbonate content seems to play a role in chemical stabilisation of metals and in a decrease of toxicity of sediments. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover effects to long term.     

Initial study on the effects of Prestige oil on human health

The big oil tanker Prestige wrecked at 130 miles from the coast of Galicia, on the Northwest of Spain, in November 19, 2002. During the accident over 40,000 tons of oil were spilled, and along the next weeks 22,000 more reached the shore in the way of three black tides. A great number of people participated in the cleaning tasks. The objective of this study was to initially evaluate the damage caused by Prestige oil in exposed individuals both from the cytogenetic and the endocrine points of view. Exposure level was determined by analysing volatile organic compounds in the environment and heavy metals in blood. Cytogenetic damage was determined by sister chromatid exchanges (SCE), and plasmatic prolactin and cortisol levels were used as biomarkers of endocrine toxicity. Finally we have determined the possible influence of GST genetic polymorphisms (GSTM1 and GSTT1 deletion polymorphisms, GSTP1 Ala105Val) on the evaluated effects. The exposed population was classified according to the performed cleaning tasks in three groups: volunteers that collaborated for 1 week (N=25), hired manual workers (N=20) and hired high-pressure cleaner workers (N=23). The control population consisted of 42 individuals. Exposure to Prestige oil caused cytogenetic damage in exposed individuals, being its effect influenced by age, sex, tobacco consumption and GSTM1 polymorphism. With regard to endocrine toxicity, our results showed that xenobiotics present in Prestige oil induced alterations in hormonal status, and thus it may be considered as an endocrine disruptor. Therefore, the selected parameters have shown to be good indicators of toxicity related to exposure to Prestige oil. In addition, data obtained point to the importance of using protective devices in preventing the effects related to the exposure.     

A novel approach to the sequential extraction of plutonium from oxic and anoxic sediment using sodium citrate to inhibit post-extraction resorption

Sequential extraction has been used extensively to study the solid partitioning of radionuclides in soils and sediments. A difficulty with sequential extraction is that radionuclides released by a particular extractant can be resorbed and artificially redistributed amongst the remaining solid phases. Here, we describe experiments (on selected model phase and natural materials), which were designed to determine whether the inclusion of a chelating agent (sodium citrate) in an established sequential extraction protocol (a) inhibits post-extraction resorption of plutonium, (b) increases non-targeted dissolution of sediment phases, and (c) gives rise to unwanted ligand competition for plutonium. The results clearly demonstrate the capacity of citrate to inhibit the resorption of plutonium from the various extractants, and confirm that there is no discernible increase in non-targeted phase dissolution, but indicate significant ligand competition with the carbonate phase. The merits of using citrate are discussed and an optimised sequential extraction protocol that includes citrate is proposed. Finally, the protocol is applied to oxic and anoxic sediments sampled in the NE Irish Sea and the Roads of Cherbourg, and it is shown that the bulk of the plutonium on these sediments is associated with the more labile geochemical fractions.     

Physico-chemical and toxicological characterization of the historic estuarine sediments: a multidisciplinary approach

The accumulation rates, the geochronology of metals and PAH contamination, and the Microtox toxicity are studied in five sediment cores (50 cm length) covering different areas of the Santander Bay, Northern Spain. Chronology given by (210)Pb and (137)Cs reveals significant differences in accumulation rates between sites (0.2-1.1 cm/year), as well as a variable degree of anthropogenic enrichment factors for Fe, Mn, Cu, Pb, Zn, Ni (from 1 to 15) and concentrations of summation Sigma 16PAHs (from 0.01 to 23.84 mg/kg dw) in sediments over the last 90 years. The results indicate the increasing contamination pressure from industrial and urban activities along the Bay. No toxic results from the Microtox test are obtained either with pore water or with normalised sediment aqueous extracts (European Norm EN 12457), suggesting low water solubility and low availability of contaminants in the studied sediments. However, the EC50 values from the Microtox Basic Solid Phase Test (BSPT) ranged from 0.03% to 2.35%, showing vertical toxicity profiles in accordance with metal and PAHs behaviour. The correlation degrees of Microtox BSPT toxicity to chemical concentration in sediment profiles are widely variable showing a high site-dependent toxicity. The oligochaete Limnodrilus hoffmeisteri has been used as a chronic bioassay over surface sediments of two of the studied sites, showing results coherent with the Microtox BSPT acute test results. Global results of the present work provide regional geochemical baselines for metals and PAHs and toxicological data now make it possible to obtain a preliminary quality assessment of the Santander Bay sediment profiles.     

Evolution and frequency (1970–2007) of combined temperature–precipitation modes in the Spanish mountains and sensitivity of snow cover

Snow cover in Spanish mountains is crucial for ensuring water availability in spring and summer months, for the success of winter tourism or for the maintenance of biodiversity in mountain ecosystems. A changing climate may affect the volume of snow cover even in high mountains, where weather conditions are usually favorable for snow accumulation. In this paper, we aim to investigate the evolution (1970–2007) of combined precipitation–temperature modes in the Spanish mountains, and the sensitivity of the snowpack to their occurrence. The climatic database “Spain02” and snow thickness data for Spanish mountains were used for this purpose. Results showed that the frequency of dry-warm and wet-warm days has increased over time in all mountain ranges, while the frequency of the “cold” modes has decreased. The thickness of the snowpack in the Pyrenees has also decreased and its evolution is negatively correlated with the frequency of dry-warm days, and positively correlated with the frequency of dry-cold and wet-cold days. This work constitutes the first approach that relates the evolution of climatic conditions favorable or unfavorable for snow accumulation and the evolution of the snowpack in Spanish mountains.     

Electrochemical degradation of amoxicillin in acidic aqueous medium using TiO2-based electrodes modified by oxides of transition metals

Environmental Science and Pollution Research - One of the most widely used antibiotics is amoxicillin (AMX), which is the most widely used in humans and animals, but it is discharged metabolically...     

Morphological responses and tolerance of a tree native to the Brazilian Cerrado Astronium fraxinifolium Schott to boron toxicity

Environmental Science and Pollution Research - The indiscriminate use of fertilizers and chemical pesticides can lead to boron contamination of the soil. Decontamination in general is expensive and...     

Amylose Modified Starches as Superabsorbent Systems for Release of Potassium Fertilizers

Journal of Polymers and the Environment - High-amylose maize starch (AS) was modified by graft copolymerization with sodium acid maleate and disodium maleate, using the KMnO4-NaHSO3 redox system,...