Potential physiological effects of pharmaceutical compounds in Atlantic salmon (<Emphasis Type="Italic">Salmo salar</Emphasis>) implied by transcriptomic analysis

Background, aim, and scope  

Pharmaceuticals are emerging pollutants widely used in everyday urban activities which can be detected in surface, ground, and drinking waters. Their presence is derived from consumption of medicines, disposal of expired medications, release of treated and untreated urban effluents, and from the pharmaceutical industry. Their growing use has become an alarming environmental problem which potentially will become dangerous in the future. However, there is still a lack of knowledge about long-term effects in non-target organisms as well as for human health. Toxicity testing has indicated a relatively low acute toxicity to fish species, but no information is available on possible sublethal effects. This study provides data on the physiological pathways involved in the exposure of Atlantic salmon as representative test species to three pharmaceutical compounds found in ground, surface, and drinking waters based on the evaluation of the xenobiotic-induced impairment resulting in the activation and silencing of specific genes.     

Linking Salmon Aquaculture Synergies and Trade-Offs on Ecosystem Services to Human Wellbeing Constituents

Salmon aquaculture has emerged as a successful economic industry generating high economic revenues to invest in the development of Chiloe region, Southern Chile. However, salmon aquaculture also consumes a substantial amount of ecosystem services, and the direct and indirect impacts on human wellbeing are still unknown and unexplored. This paper identifies the synergies and trade-offs caused by the salmon industry on a range of ecosystem services. The results show that large economic benefits due to the increase of provisioning ecosystem services are also causing a reduction on regulating and cultural services. Despite the improvement on average income and poverty levels experienced in communities closely associated with the sector, this progress is not large enough and social welfare did not improve substantially over the last decade. The rest of human wellbeing constituents in Chiloe region have not changed significantly compared to the development in the rest of the country.     

Product Guide/1970

Abstract

In Mexico City, the use and composition of fuels determine that carbon monoxide (CO) comes mostly from mobile sources, and sulfur dioxide (SO₂) from fixed and mobile sources. By simultaneously measuring hydrocarbons (HC), CO, and SO₂ in the atmosphere of Mexico City, the relative amounts coming from different sources can be estimated. Assuming that some HC are emitted proportionally to CO emissions, we can establish that [HC]₁= m1? [CO], where the proportionality constant ml corresponds to the ratio of emissions factor for HC and CO in mobile sources. Similarly for fuels containing sulfur, it can be assumed that [HC]₂ = m2 ? [SO₂]. In this way, the total HC are [HC]_total=[HC]₀+ ml ? [CO]+ m2 ? [SO₂], where [HC]₀ corresponds mainly to other sources like solvent evaporation, gas consumption, and natural emissions. In this way, it can be estimated that in Mexico City 75% of average HC comes from mobile sources, 5% from sulfur-related sources, and 19% from natural sources and solvent evaporation. Compared with the HC/CO ratio measured in the exhaust pipe of vehicles, we estimated that 70% of HC emitted from mobile sources are evaporative losses, and only 30% come through the exhaust system.     

Effects of the organophosphate insecticide azinphos-methyl on the reproduction and cholinesterase activity of Biomphalaria glabrata

Azinphos-methyl is an organophosphate insecticide used for pest control on a number of food crops in many parts of the world. The snail Biomphalaria glabrata is a freshwater gastropod widely distributed in South America, Central America and Africa. The aim of the present work was to investigate whether azinphos-methyl causes alterations in the reproduction of B. glabrata. To this end, gastropod pigmented specimens were exposed to various concentrations of the insecticide (0.021, 0.5, 2.5, and 5 mg L⁻¹) for either 2 or 14 d. Along 14 d, several reproduction parameters and cholinesterase (ChE) activity were evaluated. In each group, the number of egg masses, the number of eggs per mass, the number of hatchings, the time to hatching, and the survival of the offspring after one month of treatment was evaluated. The results showed that, depending on the concentration and time of exposure, azinphos-methyl induced alterations in the reproduction of B. glabrata. These alterations were mainly represented by a decrease in the number of egg masses, and, in some cases, by a lower number or even the total absence of hatchings. Thus, the gastropods exposed to 2.5 and 5 mg L⁻¹ of azinphos-methyl for 14 d showed ChE inhibitions higher than 35% along time and completely lost their ability to reproduce. On the other hand, exposure to high acute concentrations or exposure to low concentrations for 14 d resulted in ChE inhibition equal to or lower than 35% between 7 and 14 d of treatment and similar alterations in reproduction. These were represented by a decrease in the number of egg masses. At low pestice levels, the number of egg masses and the number of offspring resulted to be more sensitive biomarkers than ChE inhibition. It is concluded that the insecticide azinphos-methyl can cause a decline in the reproductive performance of B. glabrata.     

Accumulation,biotransformation, and biochemical responses after exposure to arsenite and arsenate in the estuarine polychaete <Emphasis Type="BoldItalic">Laeonereis acuta</Emphasis> (Nereididae)

Introduction  

This study aimed to analyze antioxidant responses and oxidative damage induced by two inorganic forms of arsenic (As; As^III and As^V) in an estuarine polychaete species, Laeonereis acuta (Nereididae). The capacity of arsenic biotransformation was also evaluated through the methylation process considering the activity of a key enzyme involved in the metabolization process.     

Spatial variability of precipitation in Spain

The spatial variability of annual and seasonal precipitation in the conterminous land of Spain has been evaluated by using correlation decay distance analysis (CDD). The CDD analysis essentially explores how the correlation between neighbouring stations varies according to distance. We analysed CDD independently for the decades 1956–1965, 1966–1975, 1976–1985, 1986–1995, and 1996–2005 using only those stations with no missing values for each decade. To this end, 972, 1,174, 1,242, 773 and 695 complete series were used for each decade, respectively. In particular, for each station and decade, we calculated the threshold distance at which the common variance between target (i) and neighbour series is higher than 50 % (r ²  = 0.5) to evaluate whether current density of the climate data set captures the spatial variability of precipitation within the study area. Results indicate that, at an annual scale, neighbouring stations with 50 % of common variance are restricted on average to about 105 km, but this distance can vary from 28 to 251 km within the study area. The lowest variability is located to the SW and in winter, while the higher spatial variability is found to the north, in the Cantabrian area, and to the east, in the Mediterranean and Pyrenees, during summer. Our results suggest that current density of climate stations (those operating in 2005) is good enough to study precipitation variability at an annual scale for winter, spring and autumn, but not enough for summer.     

Methylmercury levels and bioaccumulation in the aquatic food web of a highly mercury-contaminated reservoir

The low Ebro River basin (NE Spain) represents a particular case of chronic and long-term mercury pollution due to the presence of an industrial waste (up to 436 μg/g of Hg) coming from a chlor-alkali plant Albeit high total mercury (THg) levels have been previously described in several aquatic species from the surveyed area, methylmercury (MeHg) values in fish individuals have never been reported. Accordingly, in order to investigate bioaccumulation patterns at different levels of the aquatic food web of such polluted area, crayfish and various fish species, were analysed for THg and MeHg content. At the hot spot, THg mean values of crayfish muscle tissue and hepatopancreas were 10 and 15 times, respectively, greater than the local background level. Higher mean THg concentrations were detected in piscivorous (THg=0.848 ± 0.476 μg/g wet weight (ww); MeHg=0.672 ± 0.364 μg/g ww) than in non-piscivorous fish (THg=0.305 ± 0.163 μg/g ww; MeHg=0.278 ± 0.239 μg/g ww). Although these results indicated that THg in fish increased significantly with increasing trophic position, the percentage of the methylated form of Hg was not strongly influenced by differences in relative trophic position. This is an important finding, since the fraction of THg as MeHg in the top fish predator was unexpectedly lower than for other species of the aquatic food chain. Moreover, mean THg concentrations in piscivorous fish exceed the maximum level recommended for human consumption. From our findings, it is clear that for this specific polluted system, speciation becomes almost mandatory when risk assessment is based on MeHg, since single measurements of THg are inadequate and could lead to an over- or under-estimation of contamination levels.     

Utilizing international networks for accelerating research and learning in transformational sustainability science

A promising approach for addressing sustainability problems is to recognize the unique conditions of a particular place, such as problem features and solution capabilities, and adopt and adapt solutions developed at other places around the world. Therefore, research and teaching in international networks becomes critical, as it allows for accelerating learning by sharing problem understandings, successful solutions, and important contextual considerations. This article identifies eight distinct types of research and teaching collaborations in international networks that can support such accelerated learning. The four research types are, with increasing intensity of collaboration: (1) solution adoption; (2) solution consultation; (3) joint research on different problems; and (4) joint research on similar problems. The four teaching types are, with increasing intensity of collaboration: (1) adopted course; (2) course with visiting faculty; (3) joint course with traveling faculty; and (4) joint course with traveling students. The typology is illustrated by extending existing research and teaching projects on urban sustainability in the International Network of Programs in Sustainability, with partner universities from Europe, North America, Asia, and Africa. The article concludes with challenges and strategies for extending individual projects into collaborations in international networks.