Health News Roundup: California governor acts to stem 'epidemic' of youth vaping; Factbox: U.S. lawsuits take aim at vaping

More evidence supports helmet use by cyclists

Most Americans who are injured in cycling accidents don't wear helmets, and this is especially true of men, children, and black and Hispanic riders, a new study suggests. Researchers examined data on 76,032 cycling injuries from 2002 to 2012 and found that overall, just 22% of adults and 12% of kids were wearing helmets at the time of their bike accidents.

California governor acts to stem 'epidemic' of youth vaping

California's governor on Monday ordered a public awareness campaign on health risks posed by a "youth epidemic" of vaping, but said he lacked authority to unilaterally ban flavored e-cigarettes that he said were deliberately marketed to children. Governor Gavin Newsom, acting a day after New York Governor Andrew Cuomo announced such a ban, became the latest politician seeking to crack down on e-cigarettes and other electronic inhaling - or vaping - devices, which have exposed a new generation of young people to nicotine hazards.

Factbox: U.S. lawsuits take aim at vaping

Several deaths and potentially hundreds of illnesses have been tied to e-cigarettes, which allow users to inhale nicotine vapor, often flavored, without smoking. Lawsuits have been filed against e-cigarette maker Juul and more are expected amid increasing scrutiny. The following is a summary of how the litigation is playing out across the United States: * About 30 lawsuits have been filed over vaping-related injuries in courts around the country, including both individual lawsuits and class actions. The lawsuits target Juul Labs Inc, which controls about 75% of the e-cigarette market. Some have also named Altria Group Inc, which has a minority stake in Juul, as a defendant. Altria is the parent company of tobacco giant Philip Morris.

Potentially harmful carbon pollution reaches fetal side of placenta: study

Airborne carbon particles that can cause health problems in adults and children are getting into the placenta as it nourishes a developing fetus, a new study has found. Tissue samples from 5 pre-term and 23 full-term births found that the more airborne soot the mother was exposed to during pregnancy, the higher the number of so-called black carbon particles found in the placenta, researchers report in Nature Communications.

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