DDT and DDE concentrations in the blood of Mexican children residing in the southeastern region of Mexico

The aim of this study was to assess the levels of dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethylene (DDE) in the blood of children living in the southeastern region of Mexico. In this study, we found high levels of DDT and its principal metabolite (DDE) in the blood of children residing in the communities studied. The levels of total DDT found in our study ranged from 4,676.4 ng/g lipid to 64,245.2 ng/g lipid. All of the children in the study had detectable levels of DDT and/or DDE. In conclusion, our data indicate that children living within the study areas are exposed to high levels of DDT and DDE. Moreover, these results can be used as a trigger to revisit local policies on environmental exposures.     

When to come out from your own shell: risk-sensitive hiding decisions in terrapins

Animals should optimize the decision of when to come out from a refuge after a predators unsuccessful attack because hiding may be costly. Many prey run to hide in refuges in their habitat, whereas others are sessile and take refuge in a protective structure surrounding their body. An intermediate situation is when animals, such as turtles, have morphological structures that provide some partial protection, but they are also able to escape actively to safer refuges. This might complicate hiding decisions predicted by the theory of optimal-refuge use. We studied antipredatory tactics of Spanish terrapins (Mauremys leprosa) in response to simulated predatory attacks with different characteristics (i.e. combinations of several risk factors) and under different conditions (i.e. proximity to safe refuges), which should contribute to overall risk-level estimation. We specifically examined how risk level affected time spent withdrawn into the shell and time until turtles switched to an active escape tactic. The results showed that turtles were able to adjust their hiding behavior by assessing the risk of emerging before the predator had left the area. However, increasing hiding time may also increase the risk that the predator was able to injure or kill the turtle. Thus, the possibility of switching the antipredatory tactic to an alternative active escape to safer refuges (i.e. water) also influenced hiding times.Communicated by P. Bednekoff     

Exposure to chemical mixtures in Mexican children: high-risk scenarios

In developing countries, the management of environmental toxicants is inadequate, thus, humans may be exposed to levels higher than normal levels (background levels). Therefore, the aim of this study was to evaluate the exposure level of Mexican children to dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), lead, and polycyclic aromatic hydrocarbons [using 1-hydroxypyrene (1-OHP) as exposure biomarker] and to assess the percentage of children exposed to these four compounds at concentrations higher than normal in each community studied. We performed random sampling in eight communities in Mexico (five communities in Chiapas State and three communities in San Luis Potosi State). DDT and DDE were analyzed by gas chromatography/mass spectrometry, the quantification of lead in blood was performed using atomic absorption spectrophotometry, and 1-OHP analyses were performed using HPLC with a fluorescence detector. Elevated DDT, DDE, and 1-OHP levels were found in children living in the indigenous communities of Chiapas State, while higher blood lead levels were found in two communities in San Luis Potosí. Approximately 30 % of children living in Chiapas were exposed to all four compounds at concentrations above the guidelines for each compound, whereas 48 % of children studied were exposed to all four contaminants at concentrations higher than normal in a community in San Luis Potosí State. As expected, our results showed that in hot spots, children are exposed to levels higher than normal. Therefore, child environmental health programs are urgently needed.     

Impact of helmet use on traumatic brain injury from road traffic accidents in Cambodia

Objective: Rapid urbanization and motorization without corresponding increases in helmet usage have made traumatic brain injury due to road traffic accidents a major public health crisis in Cambodia. This analysis was conducted to quantify the impact of helmets on severity of injury, neurosurgical indication, and functional outcomes at discharge for motorcycle operators who required hospitalization for a traumatic brain injury following a road traffic accident in Cambodia.

Methods: The medical records of 491 motorcycle operators who presented to a major tertiary care center in Cambodia with traumatic brain injury were retrospectively analyzed using multivariate logistic regression.

Results: The most common injuries at presentation were contusions (47.0%), epidural hematomas (30.1%), subdural hematomas (27.9%), subarachnoid hemorrhages (12.4%), skull fractures (21.4%), and facial fractures (18.5%). Moderate-to-severe loss of consciousness was present in 36.3% of patients. Not wearing a helmet was associated with an odds ratio of 2.20 (95% confidence interval [CI], 1.15–4.22) for presenting with moderate to severe loss of consciousness compared to helmeted patients. Craniotomy or craniectomy was indicated for evacuation of hematoma in 20.0% of cases, and nonhelmeted patients had 3.21-fold higher odds of requiring neurosurgical intervention (95% CI, 1.25–8.27). Furthermore, lack of helmet usage was associated with 2.72-fold higher odds of discharge with functional deficits (95% CI, 1.14–6.49). In total, 30.1% of patients were discharged with severe functional deficits.

Conclusions: Helmets demonstrate a protective effect and may be an effective public health intervention to significantly reduce the burden of traumatic brain injury in Cambodia and other developing countries with increasing rates of motorization across the world.     

Current efforts to monitor and conserve the Eastern Imperial Eagle Aquila heliaca in Hungary

The globally threatened Eastern Imperial Eagle Aquila heliaca has been one of the flagship species of Hungarian bird conservation efforts since the 1980s. Due to these conservation activities and positive land-use changes during the last 2 decades, the Hungarian Imperial Eagle population increased from as few as approximately 20 pairs in the early 1980s to 81 pairs by 2006. Between 2002 and 2005 as part of a LIFE-Nature project, MME/Birdlife Hungary carried out particularly intensive monitoring, conservation, research, and public awareness actions. The main goal of the project was to secure the long-term sustainable increase in the Imperial Eagle population after Hungary's European Union accession in 2004. New methods were developed and applied to census and monitor the breeding and wintering population sizes. Standardized baseline land-use mapping and surveys were introduced to detect long-term land-use and prey density changes in priority areas for Imperial Eagles and to monitor the effects of key mortality factors, such as electrocution. Historical information and data gathered before and during the project period were assimilated using a Geographic Information System and incorporated into a comprehensive set of Imperial Eagle Management Guidelines.     

Identification of Enteric Viruses in Foods from Mexico City

Foodborne viruses are a common and, probably, the most under-recognized cause of outbreaks of gastroenteritis. Among the main foods involved in the transmission of human enteric viruses are mollusks, and fruits and vegetables irrigated with wastewater and/or washed with non-potable water or contaminated by contact with surfaces or hands of the infected personnel during its preparation. In this study, 134 food samples were analyzed for the detection of Norovirus, Rotavirus, and Hepatitis A virus (HAV) by amplification of conserved regions of these viruses. From the 134 analyzed samples, 14 were positive for HAV, 6 for Norovirus, and 11 for Rotavirus. This is the first report in Mexico where emphasis is given to the presence of HAV and Norovirus on perishable foods and food from fisheries, as well as Rotavirus on frozen vegetables, confirming the role of vegetables and bivalve mollusks as transmitting vehicles of enteric viruses.     

Floating kelps in Patagonian Fjords: an important vehicle for rafting invertebrates and its relevance for biogeography

Floating macroalgae are common dispersal vehicles for associated benthic invertebrates. In order to investigate the importance of kelp rafts for species dispersal in the Patagonian Fjord Region (PFR), the abundance and distribution pattern of floating kelps (Macrocystis pyrifera, Durvillaea antarctica) and of the invertebrate fauna associated with M. pyrifera were evaluated during austral spring of 2002–2005, 2008 and 2010. In the southernmost Magellan Region (MR), benthic M. pyrifera were additionally sampled to compare the community structures in both conditions. Floating kelps were abundant throughout the entire PFR, harbouring a diverse and abundant invertebrate fauna. The density of floating kelps increased towards the south. In the MR, a loss of species was observed between benthic and floating condition (e.g. decapods, echinoderms, several peracarid species), but a high diversity of organisms from all major phyla were observed on rafts. Throughout the PFR, the predominant rafting species belonged to the peracarids, molluscs and annelids, but the community composition differed between floating samples from the northern and southern zones of the PFR. Relative abundances of peracarids were higher in northern zones, whereas molluscs and annelids dominated in the southern areas. Species of the peracarid genera Peramphithoe, Gondogeneia, Bircenna and Limnoria were shared between all areas. The results suggest that kelp rafts not only contribute to local population connectivity in the PFR, but could also be an important dispersal vehicle for rafting species along the PFR in north–south direction, crossing the biogeographic boundary around Taitao Peninsula. Furthermore, the MR appears to be an important stepping stone for species dispersal via kelp rafting in the subantarctic region.