Minimization of the environmental impact of chrome tanning: a new process with high chrome exhaustion

In all tanning technology operations wastes are generated. These reach the environment as residual waters, solid and liquid waste as well as atmospheric emissions and odours.

This study tests an alternative method to the traditional tanning method at an industrial level. The new method is based on tanning without float and by significantly increasing the temperature at the end of the tanning process. The properties of the leathers obtained using the two methods have been compared and the results indicate that those leathers have similar physical, chemical, and organoleptic properties. However, the differences existing from the environmental point of view are significant. It is not necessary to use clean water for this tanning. Moreover, there is a 75% reduction of the residual float, a 91% reduction of the chrome discharged, and a 94% reduction of the chlorides discharged. A financial assessment was carried out to demonstrate that the newly proposed system is 32% more economic than the traditional one.     

Congener distribution of polybrominated diphenyl ethers in feral carp (Cyprinus carpio) from the Llobregat River, Spain

Feral carp were collected at two Spanish rivers, Anoia and Cardener, showing PBDE levels from 29 to 638 ng/g lipid weight (lw) and from 54 to 744 ng/g lw, respectively. Sediments were also collected, showing PBDE contamination between 2 and 10 ng/g dry weight (dw). Differences in PBDE profiles between sediments and fish were noticed. Contribution of BDE-47 in sediment was up to 11%, whereas it contributed 37-90% of PBDEs in fish. Similar results were observed for BDE-154, which was only detected in one sediment sample, but presented high contribution in carp. In contrast, BDE-99 contributed up to 32% in sediments, but it was not detected in fish. Similar results were observed for BDE-153, BDE-183 and BDE-209. The main reason for their concentration decrease or absence in biota may be due to low bioavailability potential or due to biotransformation processes.     

The predictive value of cytogenetic diagnosis after CVS based on 4860 cases with both direct and culture methods

Cytogenetic analysis was performed in 4860 chorionic villus samples by means of both direct preparation and long-term culture. The results of the analysis were compared with a classification including all theoretical types of combinations between the chromosomal constitution of the cytotrophoblast, extraembryonal mesoderm, and fetus, with the aim of evaluating the cytogenetic variability along the trophoblast—embryo axis. Eighteen of 29 possible combinations were found demonstrating a considerable heterogeneity. A mosaic conceptus was found in 1·5 per cent of cases, with generalized mosaicisms and confined mosaicisms in 0·2 and 1·3 per cent, respectively. Cytogenetic variability along the trophoblast—embryo axis was found in 1·42 per cent of cases. Results possibly leading to diagnostic errors (false-positive and false-negative results) were found in only 1·38 per cent. False-positive results of direct preparation were the most commonly observed discrepancy (0·8 per cent), while the incidence of false-positive results of the culture method and of both methods was 0·31 and 0·16 per cent respectively. The incidence of false-negative results was 0·1 per cent, with false-negative results of direct preparation 0·08 per cent and false-negative results of both methods 0·02 per cent. False-negative results of the culture method were not found. Our data confirm the high diagnostic accuracy of chorionic villus sampling and the utility of the combined use of the two methods in minimizing diagnostic errors and in reducing the need for follow-up amniocentesis.     

Sonographic depiction of fetal tooth germs

Recently, sonography of the fetal face has gained increasing importance in prenatal diagnosis. It is not yet clear whether sonographic depiction of fetal tooth germs would have an influence on the prenatal diagnosis of ectodermal dysplasia syndromes. During routine malformation screening, horizontal sections of fetal jaws were visualized and examined for tooth germs in 124 pregnant women following sonographic ‘facing’. Histological jaw sections of fetuses that had died in utero at various gestational ages were produced in order to examine the degree of correspondence between the sonographic and histological findings. At least four tooth germs were found in the jaws of all fetuses between 19 and 34 gestational weeks (n=104). Although jaw visualization was possible between 14 and 18 gestational weeks (n=20), the exact number and location of the tooth germs could not be determined. Assessment of tooth germs may become increasingly important, as aplasia of the tooth germs is one of the principal signs of various hereditary ectodermal diseases.     

Transverse limb reduction defects after chorion villus sampling: A retrospective Cohort study

A retrospective cohort study was performed in five Italian obstetrical centres from 1984 to 1991 in order to verify the association between chorionic villus sampling (CVS) and transverse limb reduction defects (TLRDs). TLRD rates by period of gestation at CVS were calculated, and the study's results were compared with data from the general population. Of the 3430 pregnancies for which CVS was performed, 2759 had a known outcome. The overall rate for TLRDs was 1 in 1143 CVS pregnancies, four times higher than that of the general population in Italy (1 in 4458). The rate of TLRDs was 2·9/1000 for CVS performed at 9 weeks' gestation and 1·0/1000 for CVS at 10 weeks' gestation. A scalp defect was detected in a pregnancy in which CVS was performed at 10 weeks. A high proportion of pregnancies lost to follow-up and the poor quality of the data may have affected the results. Nevertheless, our results suggest an association between CVS carried out at less than 10 weeks' gestation and TLRDs which is consistent with the findings of other studies. CVS should not be prepared at less than 10 weeks' gestation until additional evidence is obtained.     

In utero ultrasonographic features of campomelic dysplasia

A prenatal diagnosis of campomelic dysplasia in a primigravida is described. First level fetal ultrasonography demonstrated bowing and shortening of lower limbs. Second level examination allowed the correct diagnosis by demonstrating several skeletal anomalies pathognomonic of campomelic dysplasia.     

The lizard Gallotia galloti as a bioindicator of organophosphorus contamination in the Canary Islands

The aim of this study is to propose a bioindicator organism, the lizard Gallotia galloti, and a nondestructive biomarker assay, utilising serum butyrylcholinesterase, for the assessment of the toxicological impact of organophosphorus (OP) insecticides in the Canary Islands. Laboratory and field studies were performed using the OP insecticide Trichlorphon. In the laboratory study, experimental groups of Gallotia galloti were treated with 5, 50 and 100 mg/kg of Trichlorphon, respectively, and after 24 h the following enzyme activities were assayed: brain acetylcholinesterase (AChE), serum butyrylcholinesterase (BChE), microsomal carboxylesterase (CbE) and microsomal 7-ethoxyresorufin dealkylation (EROD). BChE activity was monitored in two groups of lizards treated with 50 and 100 mg/kg of Trichlorphon, respectively, for a period of 21 and 31 days after treatment. In the field study, BChE activity was detected in Gallotia galloti specimens, 24 and 48 h after treatment of an experimental area with 10 kg/ha of Dipterex sp80 (80% Trichlorphon). Three conclusions can be drawn. (1) Gallotia galloti has the features of an ideal bioindicator: high sensitivity to OPs and extremely slow recovery of serum BChE with respect to other vertebrate species; this property extends the temporal application of this biomarker in field studies. (2) A high correlation was found between the destructive biomarker brain AChE and the nondestructive biomarker serum BChE, 24 h after treatment. (3) The results of the field study show the relative 'non-toxicity' of Trichlorphon for nontarget organisms, such as lizards, at the average concentrations used in agriculture.     

Feeding activity rhythm of<Emphasis Type="Italic"> Nephrops norvegicus</Emphasis> of the western Mediterranean shelf and slope grounds

Over a 24-h time scale, benthic decapods show complex patterns of behavioural activity associated with feeding. Information is scarce on the feeding rhythms of the burrowing decapod Nephrops norvegicus (L.), especially in those deep, benthic environments typical of western Mediterranean slopes, where the fishery of this species is highly developed. In the present study, the feeding of this species was determined by means of stomach sampling, from animals captured during four continuous 24-h cycles of trawl hauls at 100–110 m and 400–430 m, in October (the autumn equinox) and June (the spring solstice). A total of 3348 stomachs were analysed for fullness and classified by means of a visual, qualitative scale. A high proportion of the stomachs collected was empty (47.2%). Feeding rhythmicity was analysed by computing a percentage value of empty stomachs for each catch. Over 4 days, the percentage values presented marked fluctuations. Therefore, periodogram and form estimate analyses were performed on time series of percentages of empty stomachs, to determine the phase and periodicity of feeding rhythms. In October, animals ingested food during the daytime, presenting nocturnal peaks of empty stomachs at both depths considered in this study. In June, nocturnal peaks of empty stomachs were recorded for the slope, while a marked feeding arrhythmia was present on the shelf. A hypothesis linking feeding activity to endogenous rhythms in locomotion, cardiac and respiratory activities is presented to account for the animals diurnal ingestion, irrespective of the depth of distribution.Communicated by S.A. Poulet, Roscoff     

Monitoring concentrations of persistent organic pollutants in the general population: the international experience

Assessing the adverse effects on human health of persistent organic pollutants (POPs) and the impact of policies aiming to reduce human exposure to POPs warrants monitoring body concentrations of POPs in representative samples of subjects. While numerous ad hoc studies are being conducted to understand POPs effects, only a few countries are conducting nationwide surveillance programs of human concentrations of POPs, and even less countries do so in representative samples of the general population. We tried to identify all studies worldwide that analyzed the distribution of concentrations of POPs in a representative sample of the general population, and we synthesized the studies' main characteristics, as design, population, and chemicals analyzed. The most comprehensive studies are the National Reports on Human Exposure to Environmental Chemicals (USA), the German Environmental Survey, and the Arctic Monitoring and Assessment Programme. Population-wide studies exist as well in New Zealand, Australia, Japan, Flanders (Belgium) and the Canary Islands (Spain). Most such studies are linked with health surveys, which is a highly-relevant additional strength. Only the German and Flemish studies analyzed POPs by educational level, while studies in the USA offer results by ethnic group. The full distribution of POPs concentrations is unknown in many countries. Knowledge gaps include also the interplay of age, gender, period and cohort effects on the prevalence of exposures observed by cross-sectional surveys. Local and global efforts to minimize POPs contamination, like the Stockholm convention, warrant nationwide monitoring of concentrations of POPs in representative samples of the general population. Results of this review show how such studies may be developed and used.