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81.
Previously, high concentrations of cadmium have been found in the hepatopancreas of the edible or brown crab (Cancer pagurus) sampled from positions north of about 67° N, compared to regions further south along the Norwegian coast, with no clear understanding why. In order to study a similar organism in the same ecosystem, the present study analyzed 210 shore crabs (Carcinus maenas) from four different locations along the Norwegian coast, two in the North and two in the South. The physiological variables size, sex, molting stage, hepatosomatic index, carapace color, and gonad maturation were registered, in attempt to explain the high inter-individual variation in cadmium levels in hepatopancreas. In contrast to the brown crabs, the shore crabs showed no clear geographical differences in cadmium concentrations. This indicates physiological differences between the two crab species. No clear and consistent correlations were found between cadmium levels and physiological parameters, except for sex, where cadmium concentration in hepatopancreas was twice as high in males compared to females. The cadmium levels also varied with season, with approximately 40 and 60% lower cadmium concentration in April than August for male and female shore crabs, respectively. None of the analyzed cadmium concentrations in muscle meat from claws exceeded EUs food safety limit, and low cadmium levels in soup prepared from shore crabs clearly indicated that this dish is not problematic regarding food safety.  相似文献   
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Purpose  

The two artificial sweeteners cyclamate (CYC) and acesulfame (ACE) have been detected in wastewater and drinking water treatment plants. As in both facilities ozonation might be applied, it is important to find out if undesired oxidation products (OPs) are formed.  相似文献   
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Earlier assessments have suggested that salmon farms may act as a source of mercury (Hg) and other elements in local marine environments. In this study, we measured 30 elements in the livers of demersal Atlantic cod (Gadus morhua) and pelagic saithe (Pollachius virens) caught in association with salmon farms (farm associated [FA]; n = 75) or at reference locations (control; n = 80) in three regions throughout the latitudinal extent of Norway (59-70° N). Concentrations of most elements (24 of 30) were higher (20-70%) in cod compared to saithe. In particular, Hg was 6.8 times higher in cod than saithe. Nine elements were significantly different between FA saithe and control saithe, but only four (Hg, U, Cr and Mn) were highest in FA saithe, and this pattern was only detected consistently across all locations for Hg. Thirteen elements differed in concentration between FA cod and control cod, but only three elements (U, Al and Ba) were higher in FA cod than controls, and this pattern was only detected consistently across all locations for Al. After controlling for a set of potentially confounding variables, the estimated concentrations of Hg in saithe livers were ~80% higher in FA fish compared to controls. In contrast, Hg concentrations were ~40% higher in control cod compared to FA cod. Our results do not support the notion that salmon farms in general increase the concentrations of potentially harmful elements in wild fish, and the distribution of Hg and other elements in cod and saithe in Norwegian coastal waters may be more influenced by habitat use, diet, geochemical conditions and water chemistry.  相似文献   
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This study describes the relations between different dimensions of leadership commitment, safety climate and attitudes toward change, and how these affect employee perceptions of safety during organizational change in a high risk environment. We collected data from a European national air navigation services provider during a volatile 3-year corporatization process that ended in the sudden collapse of a deliberate change implementation project. Surprisingly, despite visible signs of internal and external stress caused by the volatile and disruptive change process, we did not observe any change in the traditional safety metrics of incident and accident reporting during the study. The study is based on a large survey (n = 422) of individual attitudes and perceptions of safety climate, perception of leadership commitment to safety, attitudes to organizational change, and perception of safety. The data support the claim that perception of safety at least, in part, depends on individual perceptions of the leadership’s commitment to safety, and the safety climate in place at a given point in time. The model shows how employee perceptions of the leadership’s commitment to safety and safety climate are related to both attitudes toward change, and to perceived safety.  相似文献   
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Yom-Tov Y  Kvam T  Wiig Ø 《Ambio》2011,40(1):43-51
We studied the effect of various factors on body size variation of the Eurasian lynx in Norway, using data from 374 lynx collected between 1960 and 1976 and whose locality of capture, year of birth, sex, and age were known. Body size of lynx in Norway was mainly affected by sex and age. Female skull size (and by implication body size) was also positively affected by the availability of its main prey (roe deer) and by latitude, and negatively by the North Atlantic Oscillation (NAO). Male size was not affected by any of the environmental factors examined. We interpret the effects of NAO and latitude on body size through their effect on the local climate and particularly snow conditions. We suggest that females are more sensitive to environmental factors than males.  相似文献   
89.
The environment in which biology exists has dramatically changed during the last decades. Life was formed during billions of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation and the terrestrial magnetism. The existing organisms are created to function in harmony with these forces. However, in the late 19th century mankind introduced the use of electricity and during the very last decades, microwaves of the modern communication society spread around the world. Today one third of the world’s population is owner of the microwave-producing mobile phones. The question is: to what extent are living organisms affected by these ubiquitous radio frequency fields? Since 1988 our group has studied the effects upon the mammalian blood-brain barrier (BBB) by non-thermal radio frequency electromagnetic fields (RF-EMF). These have been revealed to cause significantly increased leakage of albumin through the BBB of exposed rats as compared to non-exposed animals—in a total series of about two thousand animals. One remarkable observation is the fact that the lowest energy levels give rise to the most pronounced albumin leakage. If mobile communication, even at extremely low energy levels, causes the users’ own albumin to leak out through the BBB, also other unwanted and toxic molecules in the blood, may leak into the brain tissue and concentrate in and damage the neurons and glial cells of the brain. In later studies we have shown that a 2-h exposure to GSM 915 MHz at non-thermal levels, gives rise to significant neuronal damage, seen 28 and 50 days after the exposure. In our continued research, the non-thermal effects (histology, memory functions) of long-term exposure for 13 months are studied as well as the effects of short term GSM 1,800 MHz upon gene expression. Most of our findings support that living organisms are affected by the non-thermal radio frequency fields. Studies from other laboratories in some cases find effects, while in other cases effects are not seen. Our conclusion is that all researchers involved in this field have the obligation to intensify this research in order to reduce, or avoid, the possible negative effects of the man made microwaves!  相似文献   
90.
Emerging contaminants in wastewater and sewage sludge spread on agricultural soil can be transferred to the human food web directly by uptake into food crops or indirectly following uptake into forage crops. This study determined uptake and translocation of the organophosphates tris(1-chloro-2-propyl) phosphate (TCPP) (log K ow 2.59), triethyl-chloro-phosphate (TCEP) (log K ow 1.44), tributyl phosphate (TBP) (log K ow 4.0), the insect repellent N,N-diethyl toluamide (DEET) (log K ow 2.18) and the plasticiser N-butyl benzenesulfonamide (NBBS) (log K ow 2.31) in barley, wheat, oilseed rape, meadow fescue and four cultivars of carrot. All species were grown in pots of agricultural soil, freshly amended contaminants in the range of 0.6–1.0 mg/kg dry weight, in the greenhouse. The bioconcentration factors for root (RCF), leaf (LCF) and seed (SCF) were calculated as plant concentration in root, leaf or seed over measured initial soil concentration, both in dry weight. The chlorinated flame retardants (TCEP and TCPP) displayed the highest bioconcentration factors for leaf and seed but did not show the same pattern for all crop species tested. For TCEP, which has been phased out due to toxicity but is still found in sewage sludge and wastewater, LCF was 3.9 in meadow fescue and 42.3 in carrot. For TCPP, which has replaced TCEP in many products and also occurs in higher residual levels in sewage sludge and wastewater, LCF was high for meadow fescue and carrot (25.9 and 17.5, respectively). For the four cultivars of carrot tested, the RCF range for TCPP and TCEP was 10–20 and 1.7–4.6, respectively. TCPP was detected in all three types of seeds tested (SCF, 0.015–0.110). Despite that DEET and NBBS have log K ow in same range as TCPP and TCEP, generally lower bioconcentration factors were measured. Based on the high translocation of TCPP and TCEP to leaves, especially TCPP, into meadow fescue (a forage crop for livestock animals), ongoing risk assessments should be conducted to investigate the potential effects of these compounds in the food web.  相似文献   
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