The roach (Rutilus rutilus) as a sentinel for assessing endocrine disruption.

Alterations in development and reproduction as a consequence of exposure to endocrine-disrupting chemicals (EDCs) have been demonstrated in many wildlife species. Animals living in, or closely associated with, the aquatic environment are particularly vulnerable to endocrine disruption because thousands of chemicals are actively disposed into rivers, estuaries and seas. Fish have thus been a focus in endocrine disruption studies, and some of the most comprehensive studies on the disruption of sexual development and function are on the roach (Rutilus rutilus). This paper provides a critical analysis of the roach as a sentinel for studies into endocrine disruption. The paper starts by describing what is known on the basic reproductive biology of the roach, information essential for interpreting chemical effect measures on sexual development and function. We then analyze where and how the roach has been applied to improve our understanding of the estrogenic nature of discharges from wastewater treatment works (WWTWs) and describe the phenomenon of feminized male roach in UK rivers. In this paper, the causation of these effects and issues of relative susceptibility and sensitivity of the roach to the effects of estrogenic EDCs are addressed. The paper then describes the ongoing work on the development of genetic and genomic resources for roach and analyses how these are being applied in studies to understand the mechanisms of disruption of sexual development. Finally, the paper addresses the biological significance of sexual disruption and intersex for the individual and discusses the possible implications for wild populations.     

Consumer product-related eye injury in the United States, 1998-2002

PROBLEM: Eye injury is currently a leading cause of visual impairment and monocular blindness in the United States. Information regarding consumer products associated with eye injuries can have important implications for the prevention of these injuries. METHODS: The National Electronic Injury Surveillance System (NEISS) was used to describe the types of consumer products associated with emergency department treated eye injuries in the United States from 1998 through 2002. RESULTS: The leading product type associated with eye injuries was welding equipment followed by household cleaners, basketball equipment, workshop equipment, and adhesives. Eye injuries attributed to hardware, tools, construction, sports, toys, and lawn equipment were more common among males. In females, eye injuries attributable to chemicals, housewares, storage and organization, and bed and bath items were more common. Differences were also apparent across the age spectrum. CONCLUSION: This study identified specific products and categories of products frequently associated with eye injury and prevention initiatives should focus on these items. IMPACT ON INDUSTRY: This study has identified consumer products associated with eye injuries requiring medical treatment in the United States. Manufacturers of these products could be encouraged to add or strengthen safety messages regarding the potential for eye injury.     

Epiphytic cyanobacteria maintain shifts to macroalgal dominance on coral reefs following ENSO disturbance

Macroalgal dominance of some tropical reef communities in the Eastern Pacific after coral mortality during the 1997-1998 El Ni?o Southern Oscillation (ENSO) was facilitated by protection from herbivory by epiphytic cyanobacteria. Our results do not support that reduction in number of herbivores was a necessary precursor to coral reef decline and shifts to algal reefs in this system. Rather, macroalgae dominated the community for several years after this pulse disturbance with no concurrent change in herbivore populations. While results of microcosm experiments identified the importance of nutrients, especially phosphorus, in stimulating macroalgal growth, nutrient supply alone could not sustain macroalgal dominance as nutrient-stimulated growth rates in our in situ experiments never exceeded consumption rates of unprotected thalli. In addition, thalli with nutrient-enriched tissue were preferentially consumed, possibly negating the positive effects of nutrients on growth. These tropical reefs may be ideal systems to conduct experimental tests distinguishing phase shifts from alternative stable states. Shifts were initiated by a large-scale disturbance with no evidence of a changing environment except, perhaps, dilution in herbivory pressure due to increased algal cover. Community establishment was most likely stochastic, and the community was likely maintained by strongly positive interaction between macroalgal hosts and cyanobacterial epiphytes that uncoupled consumer control of community structure.     

Wildlife Contact Rates at Artificial Feeding Sites in Texas

Given the popularity of feeding white-tailed deer (Odocoileus virginianus) in Texas and the increasing amount of corn that is distributed, more information is needed on the impacts of this activity on non-target wildlife. Our objectives were to report visitation, intra- and interspecific contact, and contact rates of wildlife at artificial feeding sites in Texas. Our study was conducted at three sites in Kleberg and Nueces counties, Texas. We trapped animals from February to April and August to September, 2009 and marked animals with passive integrated transponder (PIT) tags. At each site and season, we placed one feeder system containing a PIT tag reader within 600 m of trap locations. Readers detected PIT tags from a distance of 25 cm. We determined a contact event to occur when two different PIT tags were detected by feeder systems within 5 s. We recorded 62,719 passes by raccoons (Procyon lotor), 103,512 passes by collared peccaries (Pecari tajacu), 2,923 passes by feral swine (Sus scrofa), 1,336 passes by fox squirrels (Sciurus niger), and no passes by opossums (Didelphis virginiana) at feeder systems. For site–season combinations in which contact events occurred, we found intraspecific contact rates (contacts per day) for raccoons, collared peccaries, and feral swine to be 0.81–124.77, 0.69–38.08, and 0.0–0.66, respectively. Throughout our study we distributed ~2,625 kg of whole kernel corn, which resulted in 6,351 contact events between marked wildlife (2.4 contacts per kg of corn). If 136 million kg of corn is distributed in Texas annually, we would expect >5.2 billion unnatural contact events between wildlife would result from this activity each year in Texas. Consequently, we do not believe that it is wise for natural resource managers to maintain artificial feeding sites for white-tailed deer or other wildlife due to pathogen transmission risks.     

Phosphorus fractions in grassland soils

The partitioning of P among major chemical forms was studied in 110 non-fertilized, semi-natural grassland soils of southeastern Sweden, comprising a wide range of soil acidity and other chemical properties. The P fractions bound to Ca and Fe were closely related to soil acidity, expressed as pH-KCl, especially when calculated as % of the total pool of mineral P. The relationship was inversely linear for log10P-Fe, whereas it was strongly positively curvilinear for log10P-Ca, with a sudden decrease of this fraction below pH-KCl 4.5. Phosphate bound to Al was inversely related to pH-KCl, but the variability accounted for was rather low. Easily exchangeable phosphate, interpreted as the most labile form of P-Al, was more closely related to soil acidity, with very low values at pHg-KCl > 5.5. Soil concentration of organic P was mainly a function of its contents of organic matter. Data were treated by PCA and stepwise regression analysis.     

Effects of temperature,nutritive and metal stressors on the reproductive biology of Mytilus edulis

Experimental observations suggest that the gametogenic cycle of Mytilus edulis from Swansea Bay, South Wales (U.K.) is adversely modified by the combined effects of temperature, nutritive and sublethal metal-induced stress. During low temperature stress, oogenesis remained in the vegetative stage and vitellogenesis only commenced when temperatures were raised to ambient levels. Copper was the most toxic metal, although its uptake was slowest. A concentration of 0.05 mg l^-1 of this metal proved lethal at ambient temperatures, although at low temperatures there was no mortality. Copper suppressed both the growth of young oocytes and vitellogenesis in larger oocytes. Zinc was less toxic than copper, although this also inhibited oocyte development and resulted in severe lysis of gametes. Cadmium was the least toxic of the three metals studied and suppressed gametogenesis only in the initial stages of gonad development. The low toxicity of cadmium to gametogenesis may be a result of its high solubility and its possible storage in the digestive gland.     

Nitrous oxide nitrification and denitrification 15N enrichment factors from Amazon forest soils.

The isotopic signatures of 15N and 18O in N2O emitted from tropical soils vary both spatially and temporally, leading to large uncertainty in the overall tropical source signature and thereby limiting the utility of isotopes in constraining the global N2O budget. Determining the reasons for spatial and temporal variations in isotope signatures requires that we know the isotope enrichment factors for nitrification and denitrification, the two processes that produce N2O in soils. We have devised a method for measuring these enrichment factors using soil incubation experiments and report results from this method for three rain forest soils collected in the Brazilian Amazon: soil with differing sand and clay content from the Tapajos National Forest (TNF) near Santarém, Pará, and Nova Vida Farm, Rond?nia. The 15N enrichment factors for nitrification and denitrification differ with soil texture and site: -111 per thousand +/- 12 per thousand and -31 per thousand +/- 11 per thousand for a clay-rich Oxisol (TNF), -102 per thousand +/- 5 per thousand and -45 per thousand +/- 5 per thousand for a sandier Ultisol (TNF), and -10.4 per thousand +/- 3.5 per thousand (enrichment factor for denitrification) for another Ultisol (Nova Vida) soil, respectively. We also show that the isotopomer site preference (delta15Nalpha - delta15Nbeta, where alpha indicates the central nitrogen atom and beta the terminal nitrogen atom in N2O) may allow differentiation between processes of production and consumption of N2O and can potentially be used to determine the contributions of nitrification and denitrification. The site preferences for nitrification and denitrification from the TNF-Ultisol incubated soils are: 4.2 per thousand +/- 8.4 per thousand and 31.6 per thousand +/- 8.1 per thousand, respectively. Thus, nitrifying and denitrifying bacteria populations under the conditions of our study exhibit significantly different 15N site preference fingerprints. Our data set strongly suggests that N2O isotopomers can be used in concert with traditional N2O stable isotope measurements as constraints to differentiate microbial N2O processes in soil and will contribute to interpretations of the isotopic site preference N2O values found in the free troposphere.     

Multi-year observations on the gametogenic ecology of the Antarctic seastar <Emphasis Type="Italic">Odontaster validus</Emphasis>

This study reports the first multi-year observations on the reproductive patterns for an Antarctic predator/scavenger, Odontaster validus (Koehler 1912). Seastars were collected monthly from a shallow site (15–20 m depth) near the British Antarctic Survey (BAS) Rothera Research Station (Adelaide Island, 67°34′S 68°08′W) from July 1997 to January 2001. Reproductive condition, oocyte size frequencies and spermatogenesis were examined in at least ten seastars each month using histological and image analysis techniques. Gonad indices (GI) and pyloric caeca indices (PI) were also examined in the same samples. Female and male GIs varied seasonally, in parallel with a reduction in the proportion of large oocytes and mature sperm in the gonad in August to mid-October following winter spawning. Despite there being remarkable consistency in the timing of spawning from year to year, differences in the reproductive condition of individuals were apparent. Patterns in the digestive tissues also varied with season, peaking in December and reaching a minimum in February in two of the three study years. This weaker annual pattern may partly reflect the varied diet of this predator/scavenger species, which is not directly dependant on the timing and magnitude of the annual phytoplankton bloom. Pooled oocyte size distributions and residual analysis suggested that oogenesis progressed over 18–24 months, with the largest of the two size classes (maximum diameter = 183 μm) being spawned annually. This pattern of oocyte growth and spawning was previously reported in the early 1960s for an O. validus population from McMurdo Sound, which lies south of Rothera by 10° latitude. The extremely catholic diet of this predator/scavenger suggests the reproductive patterns of the seastar will be less susceptible to changes in food supply compared to polar suspension feeders or deposit feeders. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Estrogenic Effects of Effluents from Sewage Treatment Works

The occurrence of hermaphrodite fish in the lagoons of sewage treatment works led us to hypothesize that sewage effluent might contain a substance, or substances, estrogenic to fish. to test this hypothesis, we placed cages containing rainbow trout in the effluent from sewage-treatment works, and one to three weeks later measured the vitellogenin concentration in the plasma of the fish. Vitellogenin is a protein synthesized by the liver of oviparous fish in response to estradiol stimulation; it is then conveyed by the blood to the ovary, where it is sequestered by oocytes to form the yolk. Thus, the presence of vitellogenin in the plasma is indicative of estrogenic stimulation of the liver. an initial study, at a sewage-treatment works, showed that plasma vitellogenin concentrations rose rapidly and very markedly (over 1000-fold in three weeks) when trout were maintained in the effluent. an extensive nationwide survey was then conducted. Results were obtained from fifteen sewage-treatment works distributed throughout England. in all cases, exposure of trout to effluent resulted in a very pronounced increase (500 to 100,000-fold, depending on site) in the plasma vitellogenin concentration. Induction of vitellogenesis was also observed in carp, but to a much lesser extent than in trout.

The identity of the estrogenic substance is unknown. It is suggested that the two most likely possibilities are ethynylestradiol, originating from pharmaceutical use, or alkylphenol-ethoxylates (APE), originating from the biodegradation of surfactants and detergents during sewage treatment.

Laboratory studies on the potency of ethynylestradiol demonstrated that levels as low as 1 to 10 ng 1^-1 could generate the response shown by the caged fish and that positive responses may arise at 0.1 to 0.5 ng 1^-1. Further work is in progress on the potency of APE.     

Variations in public and private employees’ perceptions of organizational preparedness for natural disasters

Studies have demonstrated that public and private organizations differ in many respects (e.g. funding mechanisms and risk-taking capabilities). Based on this scholarship, we expect to see differences in their disaster preparedness levels. Hence, we propose the following research question: Are there variations in public and private employees’ perceptions of organizational preparedness for natural disasters? We answer this question by employing the theories of publicness and social identity. We define publicness through the core approach arguing that public and private organizations are uniquely different based on their legal status or ownership and social identity as an individual’s feeling of oneness or belongingness to a particular group or organization. Using data gathered in 2014 from a nationally representative sample of 1634 public and private employees in the United States, we posit that employees of private organizations will report higher preparedness levels in comparison to employees of public organizations. Our proposition is based on scholarship that found a negative relationship between publicness and organizational identification and a positive relationship between organizational identification and organizational performance. Contrary to our proposition, but in line with the disaster literature, the results showed that in general, employees of public organizations reported a higher preparedness level than employees of private organizations.