The fate and contamination of trace metals in soils exposed to a railroad used by Diesel Multiple Units: Assessment of the railroad contribution with multi-tool source tracking

Soil samples from cut slopes from lightly loaded railway lines used by Diesel Multiple Units for 5 years in Gdansk (Poland) were collected and analyzed for trace metals (TMs): Zn, Pb, Cd, Ni, Cr, Cu, and Fe. The main aim was to assess soil enrichment, contamination status, and distribution of TMs relative to the distance from the railway track. Extensive source tracking analyses were performed using cluster analysis (CA) and the Pb isotope ratios approach (²⁰⁶Pb, ²⁰⁷Pb, and ²⁰⁸Pb). Soil samples were affected by Cr, Cu, Pb, and Zn (max values in mg/kg d.w.: 31.1, 145, 80.5, and 115, respectively). The Enrichment Factor showed moderate (Cr, Zn, Pb) to very severe (Cu) enrichment. CA allowed TMs to be divided into two general groups: a) containing Zn, Pb, Cd with slight interaction with Cu; and b) containing Fe and Ni with slight interaction with Cr. Correlation analyses indicated Cr as an outlying TM delivered from a separate source associated with the specificity of the construction of railroad 248, where alloys containing Cr were used to counteract increasing wear-and-tear of the rails. Pb isotopic ratios in the ranges of 1.16-1.20 (²⁰⁶Pb/²⁰⁷Pb) and 2.05-2.10 (²⁰⁸Pb/²⁰⁶Pb) corresponded to anthropogenic supplementation (coal combustion, road vehicles, and railroad transport) of Pb and Pb-correlated TMs (Zn, Cd, and partly Cu). Despite the research focus on the impact of the railroad contribution, a comparison with other forms of transport indicated that road transport appeared to have a higher contributing factor to TM pollution at the investigated site. This general conclusion again emphasizes the lower environmental footprint exhibited by railway transport in comparison to road transport.

Powered-hand tools and vibration-related disorders in US-railway maintenance-of-way workers

Maintenance-of-way workers in North America who construct railroad tracks utilize specialized powered-hand tools, which lead to hand-transmitted vibration exposure. In this study, the maintenance-of-way workers were surveyed about neuro-musculoskeletal disorders, powered-hand tools and work practices. Information about vibration emission data of trade specific powered-hand tools for the North American and European Union markets was searched online to obtain respective user information of manufacturer and compared to non-commercial international data banks. The survey showed that maintenance-of-way workers frequently reported typical hand-transmitted vibration-related symptoms, and appear to be at a risk for neuro-musculoskeletal disorders of the upper extremity. Of all of the powered-hand tools used by this trade, 88% of the selected tools exceeded a=5 m/s² and were above vibration magnitudes of common tools of other comparable industries. This may create a risk if these tools are used throughout an 8-h work day and management of vibration exposure may be needed. In the North-American market, limited or no vibration emission data is available from manufacturers or distributors. Vibration emission information for powered-hand tools, including vibration emission levels (in m/s²), uncertainty factor K, and the applied testing standard/norm may assist employers, users and occupational health providers to better assess, compare and manage risk.

The effect of railways on bird diversity in farmland

With a length exceeding 210,000 km in Europe, railways are common linear features dissecting landscapes. However, the impact of railway networks on biodiversity is equivocal. In this study, we investigated the effect of railway embankments on bird diversity components in an agricultural landscape in southern Poland. Forty transects including 20 along railways and 20 as controls in open fields were established. Birds were counted twice in 2009, and environmental characteristics were estimated for each transect. Ordination techniques and generalized additive models were used to compare species composition, richness, abundance, conservation status, population trends and phylogenetic and functional diversity indices between railway and field transects. Species richness and phylogenetic diversity but not abundance nor functional diversity were higher along railway transects than along field transects. Diversity indices near railways, mostly species richness and phylogenetic diversity, were positively associated with bush cover, wet meadow cover, wetland cover and the slope of the railway but negatively associated with dry meadow cover and field cover. Our study shows that railway embankments may be beneficial for bird diversity but probably do not alter the functional properties of bird communities as much as open fields. Proper management of these linear habitats may increase their value for birds and contribute to long-term bird community persistence.

How do organizational practices relate to perceived system safety effectiveness? Perceptions of safety climate and co-worker commitment to safety as workplace safety signals

INTRODUCTION

Integrating safety climate research with signaling theory, we propose that individual perceptions of safety climate signal the importance of safety in the organization. Specifically, we expect that three work-related organizational practices (training effectiveness, procedure effectiveness, and work pressure) relate to the broader risk control system in the workplace via individual perceptions of safety climate as a broad management signal. Further, we expect this broad management signal interacts with a local environmental signal (co-worker commitment to safety) to amplify or diminish perceived system safety effectiveness.

METHOD

In a field study of oil and gas workers (N = 219; Study 1), we used mediation modeling to determine the relationships between work-related organizational practices, perceived safety climate, and perceived safety system effectiveness. In a field study of railway construction workers (N = 131; Study 2), we used moderated mediation modeling to explore the conditional role of co-worker commitment to safety.

RESULTS

We found that training effectiveness, procedure effectiveness, and work pressure predicted perceived system safety effectiveness indirectly via perceived safety climate (Studies 1 and 2) and that these indirect paths are influenced by co-worker commitment to safety (Study 2).

CONCLUSIONS

Findings suggest that perceived safety climate is driven in part by work practices, and that perceived safety climate (from managers) and co-worker commitment to safety (from the local environment) interact to shape workplace safety system effectiveness. Practical applications: The insight that training, procedures, and work pressure are meaningful predictors of perceived safety climate as a signal suggests that organizations should be cognizant of the quality of work-related practices for safety. The insight we offer on the competing versus complimentary nature of managerial safety signals (perceived safety climate) and co-worker safety signals (co-worker commitment to safety) could also be used by safety personnel to develop safety interventions directed in both areas.

Forest Edge Regrowth Typologies in Southern Sweden-Relationship to Environmental Characteristics and Implications for Management

After two major storms, the Swedish Transport Administration was granted permission in 2008 to expand the railroad corridor from 10 to 20 m from the rail banks, and to clear the forest edges in the expanded area. In order to evaluate the possibilities for managers to promote and control the species composition of the woody regrowth so that a forest edge with a graded profile develops over time, this study mapped the woody regrowth and environmental variables at 78 random sites along the 610-km railroad between Stockholm and Malmö four growing seasons after the clearing was implemented. Through different clustering approaches, dominant tree species to be controlled and future building block species for management were identified. Using multivariate regression trees, the most decisive environmental variables were identified and used to develop a regrowth typology and to calculate species indicator values. Five regrowth types and ten indicator species were identified along the environmental gradients of soil moisture, soil fertility, and altitude. Six tree species dominated the regrowth across the regrowth types, but clustering showed that if these were controlled by selective thinning, lower tree and shrub species were generally present so they could form the "building blocks" for development of a graded edge. We concluded that selective thinning targeted at controlling a few dominant tree species, here named Functional Species Control, is a simple and easily implemented management concept to promote a wide range of suitable species, because it does not require field staff with specialist taxonomic knowledge.

Analysis of fatal train-pedestrian collisions in metropolitan Chicago 2004-2012

The paper analyzes spatial and temporal data on fatal train-pedestrian collisions in the Chicago metropolitan area between 2004 and 2012. In comparing different municipalities within the region, the density of grade crossings and stations is found to increase the frequency of unintentional deaths. However, unintentional deaths do not increase with train volume suggesting that pedestrians may exercise more care around busier lines. The distribution of apparent intentional deaths is less strongly related to the density of crossings and stations suggesting that those intending self-harm will seek out a point of access. Apparent intentional deaths are more prevalent on lines with frequent passenger trains, and in municipalities with higher incomes and lower population densities. While most of the apparent intentional deaths (about 70%) are not associated with any copycat activities, the dataset contains possible clusters of intentional deaths that are proximate in both time and space. There was also a highly publicized suicide that led to a 95% increase in apparent intentional deaths throughout the region in the 18 weeks following the incident.