Embryo/larval toxicity and transcriptional effects in zebrafish (Danio rerio) exposed to endocrine active riverbed sediments

Environmental Science and Pollution Research - Sediment toxicity plays a fundamental role in the health of inland fish communities; however, the assessment of the hazard potential of contaminated...     

Urinary biomarkers and low-level environmental benzene concentration: assessing occupational and general exposure

The categories of urban workers undergoing prolonged exposure to gasoline due to vehicle emissions, evaporation and traffic fumes are considered occupationally exposed to benzene, even if at low concentrations. The aim of this study was to evaluate the specificity of unmetabolized benzene excreted in urine (UBz) and S-phenylmercapturic acid (SPMA) as biomarkers of exposure to very low levels of benzene, and to study the impact of putative individual confounders like smoking and alcohol habits, co-exposure to other toxicants and body mass index on the exposure assessment. Environmental and biological monitoring of exposure to benzene were performed in 114 Urban Policemen. The mean value of UBz in non-smokers was significantly lower than in either groups of light to moderate smokers and heavy smokers (0.24, 1.82 and 2.82 microg L(-1), respectively). On the contrary, SPMA values did not discriminate exposure resulting from smoking habits. Moreover, the concentration of UBz in non-smokers appears to be correlated with environmental benzene concentration (BenzA) (R(2)=0.13, beta=0.37, p=0.002). On the other hand, no significant correlation was found between SPMA concentration (corrected for creatinine excretion and log transformed, LogSPMA) and LogBenzA (R(2)=0.003, beta=0.05, p=0.6). Our findings reinforce previous research on the use of unmetabolized urinary benzene as a specific and sensitive biomarker of low-level exposure to benzene and confirm that smoking habits strongly influence the excretion of UBz.     

Evaluation of a high visibility enforcement project focused on passenger vehicles interacting with commercial vehicles

Introduction

In 2004, Washington State applied NHTSA's High Visibility Enforcement model used in the Click It or Ticket seat belt campaign in an attempt to reduce unsafe driving behaviors around commercial motor vehicles (CMVs). The program was called Ticketing Aggressive Cars and Trucks (TACT). This paper details the methods used to evaluate the program's effectiveness and the results of the evaluation.

Method

Four high-crash interstate highway corridors, each approximately 25 miles in length, were selected. Two of these corridors received TACT media messages and increased enforcement over an 18-month period while two comparison corridors did not receive any increased media or enforcement.

Results

A total of 4,737 contacts were made with drivers during the two enforcement waves, and 72% of these contacts led to a citation. Drivers at the intervention sites who said they saw or heard any of the TACT messages increased from 17.7% in the pre period to a high of 67.3% in the post periods. Drivers at the intervention sites also reported increased exposure to the core message of leaving more space when passing trucks (14% pre to 40% post period). The percentage of drivers who said they leave more room when passing trucks than when passing cars rose from 16% in the pre period to 24% in the post period at the intervention sites, while comparison sites showed no change. Over 150 hours of video recorded by law enforcement officers in unmarked vehicles were utilized to examine violation rates and severity of violations before and after the intervention campaigns. Statistical analyses showed that violation rates were reduced significantly at the intervention sites (between 23% and 46%), while remaining constant at the comparison sites. Analyses of the video data also showed that the seriousness of the residual violations at the intervention sites decreased.

Conclusions

Overall, the evaluation results provide a consistent picture of the effectiveness of the TACT pilot project. Success was demonstrated at every step - messages were received and understood, knowledge was changed in the intended direction, self reported driving behavior around large trucks improved, and observed driving behaviors confirmed the self reports.

Impact on Industry

After this initial success in Washington State, the TACT model will continue to be implemented and evaluated by FMCSA in an attempt to validate the program. Based on the results of this study and the consistent positive results found for other sTEP projects, it is likely that TACT will show continued success in a variety of settings and will help reduce the number and severity of crashes involving CMVs. Future research should attempt to use many of the methods described here to further validate the methods for not only evaluations of TACT programs, but also for any other highway safety programs that require measurements of the program's effectiveness.     

Traffic speeds associated with implementation of 80 mph speed limits on West Texas rural interstates

Problem

In 2006 Texas raised the daytime speed limit for passenger vehicles on segments of I-10 and I-20 from 75 to 80 mph. Methods: Traffic speeds were measured before and 3, 12, and 16 months after the limit was changed. Results: During the 16-month period following the speed limit increase, mean speeds of passenger vehicles on I-20 increased by 9 mph relative to the comparison road, where no speed limit change occurred and traffic speeds declined. On I-10 mean speeds increased by 4 mph relative to the comparison road. Limiting the analysis to the month before the speed limit change and 1 year later, the proportion of drivers exceeding 80 mph was 18 times higher on I-20 and 2 times higher on I-10. Discussion: The smaller speed increases on I-10 may be related to its proximity to the U.S. border with Mexico. Highly visible border patrol activity coincided with posting of the higher speed limit. Long-term monitoring in other states suggests that traffic speeds in Texas are likely to continue to increase. Impact on Industry: The present study adds to the wealth of evidence that increased speed limits lead to increased travel speeds. The primary countermeasures to reduce the risk of speed-related crashes include highly visible police traffic enforcement and the use of speed cameras accompanied by publicity.     

Working with cognitively impaired drivers: Legal issues for mental health professionals to consider

Introduction

Mental health professionals are gatekeepers of patient confidentiality. Yet, confidentiality held too strictly, by allowing a potentially dangerous driver to assume control of a car, endangers society. Recent court cases have mandated that mental health professionals must warn those who may be potentially harmed by patients. In spite of this, disagreements linger as to whether it is the responsibility of governmental agencies or mental health professionals to decide who is unfit to operate a vehicle because of cognitive impairment. Methods: This article addresses the legally relevant considerations when working with cognitively compromised individuals who operate a motor vehicle. Legal issues surrounding confidentiality, patient rights, foreseeable risk, and the duty to warn and protect are presented in order to understand their relationship to recent court rulings.

Impact on industry

The impact on the mental health care industry includes not only concerns about increased insurance premiums or costs due to alleged negligence or litigation expenses secondary to failure to ensure the safety of an impaired client under their care. Mental health care providers are aware that the welfare of clients with impairment to cognitive decision making ability may require unique considerations for safety such as ensuring safe and appropriate transportation.     

Television news' coverage of motor-vehicle crashes

Problem

Traffic crashes are a major cause of injury and death. Although it has been argued that a skewed estimation of personal risks may be partly attributable to news representations of mortality causes, the manners in which traffic crashes are covered in the news have not received much attention in the literature.

Method

The current study used content analysis to examine the framing of traffic crashes in television news.

Results

The data indicated that Flemish television news does not report traffic crashes from a public health perspective and consequently it misses opportunities to inform the public on the causes and consequences of risk-taking in traffic.

Impact on industry

It is important that professionals are aware of these findings and stress contextual factors surrounding traffic crashes in their communication with journalists. This may lead to more accurate reports and a more accurate risk perception of viewers.     

Risks older drivers pose to themselves and to other road users

Problem

Studies have shown that older drivers have high death rates and lower rates of involvement in crashes that kill others; but most studies have not considered drivers' responsibility for their crashes, and many have considered only one particular measure of risk.

Method

This study examines risks that drivers of various ages pose to themselves and to others on per-driver, per-trip, and per-mile bases, taking responsibility for crashes into account, using United States fatal crash data from 1999 through 2003 and travel estimates from 2001.

Results

Relative to other age groups, drivers aged 85 and older face the highest risk of their own death, whereas teens pose the greatest risk to passengers, occupants of other vehicles, and non-motorists.

Discussion

The oldest drivers pose more risk to other road users than middle-aged drivers do; the degree of their excess risk depends strongly upon how risk is measured.

Impact on industry

These results demonstrate the importance of keeping clear the meaning and implications of various risk measures.     

Epidemiology of subway-related fatalities in New York City, 1990-2003

Problem

Subway transit is a relatively safe mode of transportation, yet compared to all other forms of mass transit in the United States (U.S.), subways have the highest fatality rate. The aim of this paper is to characterize subway-related fatalities in order to identify opportunities for risk reduction.

Method

Medical examiner records for all New York City (NYC) subway-related deaths (1990-2003) were reviewed. Data were abstracted on decedents' demographics and autopsy findings, including laboratory findings.

Results

There were 668 subway-related fatalities, of these, 10 (1.5%) were homicides, 343 (51.3%) were determined to be suicides, and 315 (47.2%) were accidental. Although decedent characteristics varied between fatality categories, they were not particularly informative with regard to prevention.

Conclusion

Prevention strategies that focus on structural controls are likely to be most efficacious in improving the overall safety of the NYC subway systems.

Impact on industry

These findings suggest that structural rather than individual-level interventions would be most successful in preventing subway fatalities.     

An ethnography of low-income mothers' safeguarding efforts

Problem

Children living in lower-income environments are at greater risk for unintentional injuries. However, little is known about the safety practices of mothers living in low-income situations.

Method

This ethnographic study explored the child safeguarding experiences of low-income mothers using in-home interviews and observations.

Results

Mothers' safeguarding efforts included cognitive and emotional work, child directed work, and work directed at the physical and social environments. Factors that influenced the women's safeguarding included the quality of the indoor space, availability of safe play space, traffic hazards, sibling interactions, child care supports, relationships with neighbors, and trust in community services.

Discussion

These findings have implications for the conceptualization of safeguarding practices and provide insight about the experiences of mothers living on low-incomes.

Impact on Industry

When developing safety interventions, program planners should consider the views and practices of mothers as well as contextual factors in the physical and social environments.