Toxicological availability of nickel to the benthic oligochaete Lumbriculus variegatus

It is generally accepted that the bioavailability of metals in sediments is influenced by the presence of acid volatile sulfides (AVS). The pore water hypothesis predicts that, if the molar concentration of simultaneously extracted metals (SEM) in a sediment is smaller than the molar concentration of AVS, the free metal ion activity in the pore water is very small and that consequently no metal toxicity in short-term toxicity tests is observed. In this study we examined (1) if this concept can be extended to predict the absence of chronic Ni toxicity to the oligochaete deposit-feeding worm Lumbriculus variegatus and (2) if the organic carbon normalized excess SEM; i.e. [SEM-AVS]/f(OC) predicts the magnitude of Ni toxicity to L. variegatus. A 28-day toxicity experiment was performed in which biomass production of L. variegatus was determined in two natural sediments with different [AVS] and f(OC), spiked at different Ni concentrations. The absence of toxicity is predicted correctly by the [SEM-AVS]<0 criterion when only the 0-1 cm surface layer of the sediment is considered, but not when the whole bulk sediment is considered (0-3 cm). In both sediments, the same [SEM-AVS]/f(OC) at the surface corresponds with a similar decrease in L. variegatus biomass. Thus, [SEM-AVS]/f(OC) in the surface layer accurately predicts the magnitude of toxicity. This measure is therefore a good estimator of toxicologically available Ni. On the other hand, the free Ni(2+) ion activity in the overlying water appeared to be an equally good predictor of the magnitude of toxicity. Consequently, it was not possible to determine the relative importance of the overlying water and pore water exposure route with the semi-static laboratory experiments.     

Vocal alliances in Chacma baboons (<Emphasis Type="Italic">Papio hamadryas ursinus</Emphasis>)

Theory predicts that females in species with matrilineal dominance hierarchies should use nepotistic support systems to maintain their family’s rank. Female Old World monkeys, however, form alliances against other females at surprisingly low rates. Nonetheless, in many species, females utter threat vocalizations when observing others’ disputes, suggesting that these vocalizations may function as ‘vocal alliances’. We describe a playback experiment testing the efficacy of vocal alliances in free-ranging female baboons. Subjects were played the same female’s threat-grunts under three separate conditions: after being threatened by the signaller’s close relative to mimic kin support, after being threatened by a female maternally unrelated to the signaller to mimic non-kin support, and after a friendly interaction with the signaller’s close relative as a control. Subjects responded more strongly to the playback and avoided the signaller and her matrilineal relatives for a longer period of time in kin support trials than in either non-kin support or no aggression trials. In contrast, there was no difference in subjects’ behaviour between non-kin support and no aggression trials. These results corroborate observational data showing that vocal support occurs at a higher rate than physical support in female baboons, and that kin are more likely to provide vocal support than non-kin. We conclude that vocal support plays a similar role as physical support in the alliances of female baboons.     

Affluence,occupational safety and ergonomics: are they interdependent?

The number of fatal occupational injuries (FOI), the number of scientific publications in ergonomics (SP) and the gross domestic product (GDP) of 30 countries were investigated for their mutual dependence. This article shows that, although the ratio of FOI/SP decreases exponentially with a linear increase in the GDP, GDP may be only one of the major influencing factors.     

Statistical analysis of regulatory ecotoxicity tests.

ANOVA-type data analysis, i.e.. determination of lowest-observed-effect concentrations (LOECs), and no-observed-effect concentrations (NOECs), has been widely used for statistical analysis of chronic ecotoxicity data. However, it is more and more criticised for several reasons, among which the most important is probably the fact that the NOEC depends on the choice of test concentrations and number of replications and rewards poor experiments, i.e., high variability, with high NOEC values. Thus, a recent OECD workshop concluded that the use of the NOEC should be phased out and that a regression-based estimation procedure should be used. Following this workshop, a working group was established at the French level between government, academia and industry representatives. Twenty-seven sets of chronic data (algae, daphnia, fish) were collected and analysed by ANOVA and regression procedures. Several regression models were compared and relations between NOECs and ECx, for different values of x, were established in order to find an alternative summary parameter to the NOEC. Biological arguments are scarce to help in defining a negligible level of effect x for the ECx. With regard to their use in the risk assessment procedures, a convenient methodology would be to choose x so that ECx are on average similar to the present NOEC. This would lead to no major change in the risk assessment procedure. However, experimental data show that the ECx depend on the regression models and that their accuracy decreases in the low effect zone. This disadvantage could probably be reduced by adapting existing experimental protocols but it could mean more experimental effort and higher cost. ECx (derived with existing test guidelines, e.g., regarding the number of replicates) whose lowest bounds of the confidence interval are on average similar to present NOEC would improve this approach by a priori encouraging more precise experiments. However, narrow confidence intervals are not only linked to good experimental practices, but also depend on the distance between the best model fit and experimental data. At least, these approaches still use the NOEC as a reference although this reference is statistically not correct. On the contrary, EC50 are the most precise values to estimate on a concentration response curve, but they are clearly different from the NOEC and their use would require a modification of existing assessment factors.     

International trade causes large net economic losses in tropical countries via the destruction of ecosystem services

Despite the large implications of the use of tropical land for exports (“land absorption”) on ecosystem services (ES) and global biodiversity conservation, the magnitude of these externalities is not known. We quantify the net value of ES lost in tropical countries as a result of cropland, forestland and pastureland absorption for exports after deducting ES gains through imports (“land displacement”). We find that net ES gains occur only in 7 out of the 41 countries and regions considered. We estimate global annual net losses of over 1.7 x 10¹² international dollars (I$) (I$1.1 x 10¹² if carbon-related services are not considered). After deducting the benefits from agricultural, forest and livestock rents in land replacing tropical forests, the net annual losses are I$1.3 and I$0.7 x 10¹², respectively. The results highlight the large magnitude of tropical ES losses through international trade that are not compensated by the rents of land uses in absorbed land.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-016-0768-7) contains supplementary material, which is available to authorized users.     

Fetal fibrochondrogenesis at 26 weeks' gestation

An Erratum has been published for this article in Prenatal Diagnosis 22(13) 2002, 1241. Fibrochondrogenesis is a rare and lethal osteochondrodysplasia with an autosomal recessive mode of inheritance. We report a male fetus in which the diagnosis of lethal osteochondrodysplasia was suspected on prenatal ultrasound and radiological examinations during the second trimester of pregnancy. After termination of pregnancy, fibrochondrogenesis was diagnosed by radiological examination and histological study of fetal bones. Interwoven fibrous septa and fibroblastic degeneration of chondrocytes are pathognomonic. The recurrence rate is 25% and accurate diagnosis is necessary to enable genetic counselling. Copyright © 2002 John Wiley & Sons, Ltd.     

Case report: a prenatal case of Jarcho–Levin syndrome diagnosed during the first trimester of pregnancy

The Jarcho–Levin syndrome is a specific form of spondylocostal/spondylothoracic dysostosis. There have been various classifications of this syndrome. We present the case of a severe prenatal Jarcho–Levin syndrome, diagnosed by ultrasound examination during the first trimester of pregnancy in a family with no previous medical history of an affected child. X-ray exploration, high-resolution spiral computed tomography and autopsy confirmed the diagnosis. Copyright © 2003 John Wiley & Sons, Ltd.     

Fate of CL-20 in sandy soils: degradation products as potential markers of natural attenuation

Hexanitrohexaazaisowurtzitane (CL-20) is an emerging explosive that may replace the currently used explosives such as RDX and HMX, but little is known about its fate in soil. The present study was conducted to determine degradation products of CL-20 in two sandy soils under abiotic and biotic anaerobic conditions. Biotic degradation was prevalent in the slightly acidic VT soil, which contained a greater organic C content, while the slightly alkaline SAC soil favored hydrolysis. CL-20 degradation was accompanied by the formation of formate, glyoxal, nitrite, ammonium, and nitrous oxide. Biotic degradation of CL-20 occurred through the formation of its denitrohydrogenated derivative (m/z 393 Da) while hydrolysis occurred through the formation of a ring cleavage product (m/z 156 Da) that was tentatively identified as CH₂N-C(N-NO₂)-CHN-CHO or its isomer N(NO₂)CH-CHN-CO-CHNH. Due to their chemical specificity, these two intermediates may be considered as markers of in situ attenuation of CL-20 in soil.