Transportation

Some two million hybrid electric vehicles (HEVs) have been sold in the United States since commercial production began in 1999. Among the advantages typically mentioned are that hybrids are cleaner, more energy-efficient and quieter. However, one of these apparent benefits carries with it potential risks for other road users, who are accustomed to an environment dominated by louder combustion-engine vehicles (CEVs).

Drunk driving is the leading cause of motor vehicle deaths in the United States, and hundreds of thousands of alcohol-related automobile accidents continue to take place each year.  Many studies have explored the impacts of alcohol taxes and traffic laws on the incidence of these crashes.

The increased global production of biofuels such as ethanol has become a subject of controversy, as land formerly dedicated to the growing of food crops is repurposed to meet energy needs. Each year, more crops such as sugar, palm oil, corn and cassava are diverted for these purposes.

Prior to March 2011, parents in the United States were advised to keep their child’s car seat rear-facing at least until the child weighed 20 pounds and turned 1 year old, at which point the car seat might safely be turned around to face forward during travel. That prevailing guideline changed when the American Academy of Pediatrics issued a new recommendation that the position of car seats should be kept rear-facing until the child is 2 years old.

Marijuana usage in America rose 6.9% between 2009 and 2010, when some 17.4 million Americans reported using the drug. Sixteen states now permit the medical use of marijuana for diseases such as glaucoma and multiple sclerosis, but the drug’s growing popularity is primarily due to more recreational users ages 18 to 34, according to the Substance Abuse and Mental Health Services Administration.

There are four primary options for urban transit systems: bus, bus rapid transit, light rail and heavy rail. There has been considerable debate over the systems’ comparative advantages, from lower construction costs to greater carrying capacity.

Every year, traffic accidents kill more than a million people and injure close to 50 million around the world. As tragic and needless as these deaths are, they’re expected to increase over time: By 2020, traffic crashes will be third in the world ranking of burden of disease, as measured in disability-adjusted life years.

Train and subway stations play a significant role in both transit networks and the urban environment. While numerous studies have examined stations’ effect on property values, the results have been mixed: Some show a negative impact, others insignificant differences, and some indicate positive effects.