Computer image generation for job simulation: An effective approach to occupational Risk Analysis

The paper deals with the general approach and features of the computer image generation for job simulation (CIGJS) method, as specially developed to support the Job Safety Analysis (JSA) technique.Starting from some general considerations on the occupational safety and health statistical data collection in Italy, when compared to US methodology, the paper provides an overview of the CIGJS method, developed to improve the effectiveness and usability of the traditional JSA.A case study is discussed in order to highlight how CIGJS makes the use of the JSA technique possible also at the design stage (this being fundamental according to a Prevention through Design approach), and allows to control the effectiveness of the adopted countermeasures.The application of the method complies with the basic European Directives requirements both on workers’ safety and health and on machinery analysis.Furthermore, CIGJS may substantially aid workers’ education and training, to the point of being a possible simulation-training device.     

Vaquita Bycatch in Mexico's Artisanal Gillnet Fisheries: Driving a Small Population to Extinction

Abstract: The world's most endangered marine cetacean, the vaquita (   Phocoena sinus ), continues to be caught in small-mesh gillnet fisheries throughout much of its range. We monitored fishing effort and incidental vaquita mortality in the upper Gulf of California, Mexico, from January 1993 to January 1995 to study the magnitude and causes of the incidental take. Of those factors studied, including net mesh size, soaktime, and geographic area, none contributed significantly to the incidental mortality rate of the vaquita, implying that the principal cause of mortality is fishing with gillnets per se . The total estimated incidental mortality caused by the fleet of El Golfo de Santa Clara was 39 vaquitas per year (95% CI = 14, 93), over 17% of the most recent estimate of population size. El Golfo de Santa Clara is one of three main ports that support gillnet fisheries throughout the range of the vaquita. Preliminary results indicate that fishing effort for San Felipe, Baja California, is comparable to that of El Golfo de Santa Clara, suggesting that this estimate of incidental mortality of vaquitas represents a minimum. We strongly recommend a complete and permanent ban on gillnets in the area. Alternative or supplemental mitigation strategies include (1) a maximum annual allowable mortality limit of vaquitas; (2) mandatory observer coverage of all boats fishing within the Upper Gulf of California and Colorado River Delta Biosphere Reserve; (3) extension of the Upper Gulf of California and Colorado River Delta Biosphere Reserve to encompass all known vaquita habitat; (4) rigorous enforcement of new and existing regulations; and (5) development of alternative sources of income for gillnet fishers.     

Persistent organic pollutants in sea bass (Dicentrarchus labrax L.) in two fish farms in the Mediterranean Sea

We analyzed polychlorobiphenyls (PCBs), perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) in the edible part of farmed sea bass reared in two fish farms in Liguria (Northern Italy). The aim was to determine the contamination levels and human exposure to these chemicals through fish consumption. Concentrations of “dioxin-like” PCBs (DL-PCBs) ranged from 0.033 to 0.759 pg Σ_TEQ-PCB g⁻¹ whole weight (w.w.) in fish farm 1 and from 0.032 to 1.60 pg Σ_TEQ-PCB g⁻¹ w.w. in fish farm 2, and the six indicators of “non-dioxin-like” (NDL-PCBs) from 0.538 to 9.33 ng Σ_6PCB g⁻¹ w.w. and from 1.62 to 27.6 ng Σ_6PCB g⁻¹ w.w. Concentrations were generally lower in farm 1 than in farm 2. One reason for this difference might be the proximity of farm 2 to the seaport of La Spezia, which could be a punctual source of pollutants influencing the contamination of the water in the farm. Principal component analysis (PCA) showed differences also in the congeners profiles for the two sites, with higher-chlorinated PCBs more abundant in farm 1, and lower-chlorinated PCBs were more abundant in farm 2. Most of the concentrations of PFOS and PFOA were below the limit of detection (LOD 0.05 ng g⁻¹ w.w.). Only about 10% of the samples analyzed had levels slightly higher than the LOD. Assessments of exposure using these data showed that consumption of farmed fish may contribute significantly to PCBs through the diet, whereas the contribution of PFOS and PFOA seems to be low.     

Characterization of the olfactory impact around a wastewater treatment plant: optimization and validation of a hydrogen sulfide determination procedure based on passive diffusion sampling

A monitoring program based on an indirect method was conducted to assess the approximation of the olfactory impact in several wastewater treatment plants (in the present work, only one is shown). The method uses H2S passive sampling using Palmes-type diffusion tubes impregnated with silver nitrate and fluorometric analysis employing fluorescein mercuric acetate. The analytical procedure was validated in the exposure chamber. Exposure periods ofat least 4 days are recommended. The quantification limit of the procedure is 0.61 ppb for a 5-day sampling, which allows the H2S immission (ground concentration) level to be measured within its low odor threshold, from 0.5 to 300 ppb. Experimental results suggest an exposure time greater than 4 days, while recovery efficiency of the procedure, 93.0+/-1.8%, seems not to depend on the amount of H2S collected by the samplers within their application range. The repeatability, expressed as relative standard deviation, is lower than 7%, which is within the limits normally accepted for this type of sampler. Statistical comparison showed that this procedure and the reference method provide analogous accuracy. The proposed procedure was applied in two experimental campaigns, one intensive and the other extensive, and concentrations within the H2S low odor threshold were quantified at each sampling point. From these results, it can be concluded that the procedure shows good potential for monitoring the olfactory impact around facilities where H2S emissions are dominant.     

Sun light degradation of 4-chloroaniline in waters and its effect on toxicity. A high performance liquid chromatography - Diode array - Tandem mass spectrometry study

This paper studies the degradation reactions that 4-chloroaniline can naturally undergo in waters for the action of sun light. 10.00 mg L⁻¹ 4-chloroaniline aqueous solution, without any addition of organic solvent, are undergone to photoirradiation under conditions that simulate sun light. The degradation pathway, followed by HPLC-DAD-MS/MS methods, is complex since the pollutant gives rise to many photoproducts: the predominant species are characterized by m/z values of 217 (P5) and 218 (P6) and are compatible with dimeric structures of 4-chloroaniline. Vibrio fischeri tests indicate that the photoproducts of 4-chloroaniline are characterized by a toxicity level significantly greater than the precursor.     

What is the acceptable margin of error for the oxygen uptake method in evaluating the reactivity of organic waste?

The acceptable margin of error for the organic waste reactivity measured by the oxygen uptake method was assessed. Oxygen uptake was determined by the Dynamic Respiration Index (DRI) (mgO₂/kgVS h). The composed uncertainty (uC) of the experimental set up used for the DRI test was evaluated and the uncertainty (u) of all the components of the apparatus was evaluated. A procedure for calculating the uC of the apparatus is proposed. The components affecting the uC of the DRI to a more significant extent were the one of the oxygen mass rate and the u of the amount of VS in the sample analyzed. For a confidence level of 99.73%, the extended uC (UC) interval for a DRI = 1024 mgO₂/kgVS h was ±440 mgO₂/kgVS h, whereas for a DRI = 3489 mgO₂/kgVS h, the UC interval was ±1288 mgO₂/kgVS h. When oxygen consumption and VS content become lower than 600 mgO₂/h and 0.9 kg, respectively, the UC interval is similar to the measured DRI.     

Concentrations of trace elements in tissues of loggerhead turtles (Caretta caretta) from the Tyrrhenian and the Ionian coastlines (Calabria,Italy)

Environmental Science and Pollution Research - Toxic trace elements from both, natural and anthropogenic origin, pose a threat to aquatic environments and marine wildlife due to their long-range...