We developed a model for evaluating the environmental risk of persistent organic pollutants (POPs) to aquatic organisms. The model is based on fuzzy theory and uses information provided by international experts through a questionnaire. It has been tested in two case studies for a particular type of POPs: brominated flame retardants (BFRs). The first case study is related to the EU-funded AQUATERRA project, with sampling campaigns carried out in two Ebro tributaries in Spain (the Cinca and Vero Rivers). The second one, named the BROMACUA project, assessed different aquatic ecosystems in Chile (San Vicente Bay) and Colombia (Santa Marta Marsh). In both projects, the BFRs under study were polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). However, the model can be extrapolated to other POPs and to different aquatic ecosystems to provide useful results for decision-makers.

The Air Quality Standards for Particulate Matter (PM) at high altitude urban areas in different countries, must consider the pressure and temperature due to the effect that these parameters have on the breath volume.This paper shows the importance to correct Air Quality Standards for PM considering pressure and temperature at different altitudes. Specific factors were suggested to convert the information concerning PM, from local to standard conditions, and adjust the Air Quality Standards for different high altitudes cities. The correction factors ranged from: 1.03 for Santiago de Chile to 1.47 for El Alto Bolivia. Other cities in this study include: Mexico City, México; La Paz, Bolivia; Bogota, Cali and Medellin, Colombia; Quito, Ecuador and Cuzco, Peru.If these corrections are not considered, the atmospheric concentrations will be underestimated.

Tropospheric ozone is a secondary pollutant whose primary sources are volatile organic compounds and nitrogen oxides. The national standard is exceeded on a third of summer days in some areas of the Chilean Metropolitan Region (MR). This study reports normalized springtime experimental emissions factors (EF) for biogenic volatile organic compounds from tree species corresponding to approximately 31% of urban trees in the MR. A Photochemical Ozone Creation Index (POCI) was calculated using Photochemical Ozone Creation Potential of quantified terpenes. Ten species, natives and exotics, were analysed using static enclosure technique. Terpene quantification was performed using GC-FID, thermal desorption, cryogenic concentration and automatic injection. Observed EF and POCI values for terpenes from exotic species were 78 times greater than native values; within the same family, exotic EF and POCI values were 28 and 26 times greater than natives. These results support reforestation with native species for improved urban pollution management.

Cerebrovascular accidents, or strokes, are the second leading cause of mortality and the leading cause of morbidity in both Chile and the rest of the world. However, the relationship between particulate matter pollution and strokes is not well characterized. The association between fine particle concentration and stroke admissions was studied. Data on hospital admissions due to cerebrovascular accidents were collected from the Ministry of Health. Air quality and meteorological data were taken from the Air Quality database of the Santiago Metropolitan Area. Santiago reported 33,624 stroke admissions between January 1, 2002 and December 30, 2006. PM2.5 concentration was markedly seasonal, increasing during the winter. This study found an association between PM2.5 exposure and hospital admissions for stroke; for every PM2.5 concentration increase of 10 μg m−3, the risk of emergency hospital admissions for cerebrovascular causes increased by 1.29% (95% CI 0.552%–2.03%).

The main aim of this study was to determine the occurrence of resistant bacteria in florfenicol-treated and untreated scallop larval cultures from a commercial hatchery and to characterize some selected florfenicol-resistant strains. Larval cultures from untreated and treated rearing tanks exhibited percentages of copiotrophic bacteria resistant to florfenicol ranging from 0.03% to 10.67% and 0.49–18.34%, respectively, whereas florfenicol resistance among oligotrophic bacteria varied from 1.44% to 35.50% and 3.62–95.71%, from untreated and treated larvae, respectively. Florfenicol resistant microbiota from reared scallop larvae mainly belonged to the Pseudomonas and Pseudoalteromonas genus and were mainly resistant to florfenicol, chloramphenicol, streptomycin and co-trimoxazole. This is the first study reporting antimicrobial resistant bacteria associated to a shellfish hatchery and the results suggest that a continuous surveillance of antimicrobial resistance even in absence of antibacterial therapy is urgently required to evaluate potential undesirable consequences on the surrounding environments.

Anthropogenic marine debris (AMD) is frequently studied on sandy beaches and occasionally in coastal waters, but links between these two environments have rarely been studied. High densities of AMD were found in coastal waters and on local shores of a large bay system in northern-central Chile. No seasonal pattern in AMD densities was found, but there was a trend of increasing densities over the entire study period. While plastics and Styrofoam were the most common types of AMD both on shores and in coastal waters, AMD composition differed slightly between the two environments. The results suggest that AMD from coastal waters are deposited on local shores, which over time accumulate all types of AMD. The types and the very low percentages of AMD with epibionts point to mostly local sources. Based on these results, it can be concluded that a reduction of AMD will require local solutions.

The AZTI’s marine biotic index (AMBI), an ecological indicator for managing estuarine and coastal waters worldwide, was tested in two fjords in Chilean Patagonia. The Aysen Fjord (42° Lat. S) supports intensive salmon farming in coastal ecosystems, while the Baker Fjord (48° Lat. S) is currently just beyond the limit of the southern expansion of salmon concessions. The ecological status of the Aysen Fjord was classified as good, while the status of the Baker Fjord was classified as high and unbalanced. These differences were consistent with our expectations, illustrating the effect of local environmental conditions and human activities, combined with river inputs into semi-confined fjords. This method is appropriate for the evaluation of the ecological status of the fjords, but requires a sufficient amount of data for the robust environmental assessment as proposed by the Water Framework Directive (WFD).

The volatile monoterpene alpha-pinene has been measured in sediments of a selected area at "Carlos Anwandter" Nature Sanctuary, a Ramsar protected wetland located at the northwest of Valdivia City, south-central Chile. The ecosystem was seriously damaged by an uncontrolled liquid emission of a pulp mill (CELCO-Arauco) located about 15 km upstream of Rio Cruces during 2004. Exploratory data analysis was applied to analytical data collected from sediment samples, having found alpha-pinene as a reiterative chemical at relatively high concentrations in some specific areas of the wetland. The decrease of the total concentration of alpha-pinene in the area under study is coincident with a point contamination that occurred during 2004 (12,240 ng g(-1)) showing a decay in 2005 (7,890 ng g(-1)) and middle of 2006 (4,060 ng g(-1)). The following years, last 2006, 2008, and 2009, show a relatively constant concentration with a clear tendency toward baseline levels (2,460-2,640 ng g(-1)). Since the decrease of concentrations of alpha-pinene in sediments in the period 2004-2009 shows an opposite trend as compared to the surface area increase of pine and eucalyptus plantation in Region de Los Rios, and not having found potential sources of alpha-pinene by anthropogenic activities other than the pulp mill in the area under study, it may be finally concluded that this compound did not enter the bodies of water from a gradual and natural process; instead there is a base to sustain anthropogenic input. alpha-Pinene in sediments may be a plausible chemical tracer capable of detecting pollution events over time and its impacts in aquatic ecosystems as well as changes in aquatic ecosystems produced by improperly treated pulp mill liquid emissions that use pine and eucalyptus species.

The present study consisted of an in vitro experiment based on columns to restore a soil affected by the tsunami of 27 February 2010 that struck the Coliumo District, Bio-Bio region, Chile. The agricultural productivity of many coastal lands was severely affected, rendering them unfit for crop production. Composite soil samples were taken at 0 to 20 cm soil depth in Coliumo, Bio-Bio region. The initial physical and chemical analysis showed textural changes, low pH, high levels of electrical conductivity (EC), sodium (Na⁺), and sulfate (SO₄²⁻), whereas bioassay tests showed severe toxicity for lettuce (Lactuca sativa L.) seeds. Germination index (GI), length of hypocotyl (LH), and length of radicle (LR) were used as indicators in the bioassay tests. Two different treatments were used: T1 = soil amended with 7.7 t ha⁻¹ of limestone (CaCO₃) and T2 = soil amended with 7.7 t ha⁻¹ of gypsum (CaSO₄). A control treatment (T0) with unamended soil was included. Each treatment received a total of 1,100 mm of clean water (4 water loads, 275 mm each), which was equivalent to the mean annual precipitation of the area studied. The T2 treatment produced a significant decrease in the concentration of Na⁺ (8.27 to 0.16 meq L⁻¹), decreased EC (1.58 to 0.03 dS m⁻¹), and increased pH from 4.83 to 6.27 in the soil under study. Leaching of Na⁺ and SO₄²⁻ with successive water loads was effective in the soil. The bioindicators as GI, LH and LR revealed that T2 was more effective than T1 and control in removing Na and SO₄ analytes from the soil matrix. The CaSO₄ amendment showed good potential for seed development, but further research on plant growth to maturity is required to determine yield parameters in the affected area.

Dinophysis and Phalacroma species containing diarrheic shellfish toxins and pectenotoxins occur in coastal temperate waters all year round and prevent the harvesting of mussels during several months each year in regions in Europe, Chile, Japan, and New Zealand. Toxicity varies among morphologically similar species, and a precise identification is needed for early warning systems. Molecular techniques using ribosomal DNA sequences offer a means to identify and detect precisely the potentially toxic species. We designed molecular probes targeting the 18S rDNA at the family and genus levels for Dinophysis and Phalacroma and at the species level for Dinophysis acuminata, Dinophysis acuta, and Dinophysis norvegica, the most commonly occurring, potentially toxic species of these genera in Western European waters. Dot blot hybridizations with polymerase chain reaction (PCR)-amplified rDNA from 17 microalgae were used to demonstrate probe specificity. The probes were modified along with other published fluorescence in situ hybridization and PCR probes and tested for a microarray platform within the MIDTAL project ( http://www.midtal.com ). The microarray was applied to field samples from Norway and Spain and compared to microscopic cell counts. These probes may be useful for early warning systems and monitoring and can also be used in population dynamic studies to distinguish species and life cycle stages, such as cysts, and their distribution in time and space.