Fifteen years ago, the federal government said “no” to piracetam. This was a proposed new ingredient that a company had hoped to market as a dietary supplement. In 2004, the U.S. Food and Drug Administration rejected the company’s application, citing “concerns about the evidence” that supposedly showed piracetam was safe.

Nearly two years ago, Jeremiah Mock heard a student in Marin County, California, complain that her school was littered with e-cigarette waste. A health anthropologist by training, Mock did some shoe-leather investigating in a student parking lot, where he found a significant amount of e-cigarette and tobacco trash. Surprised, Mock went further.

Last October, Erick Solis, a 19-year-old temp worker at a Los Angeles food company, lost two fingers when his hand got caught in an unguarded dough-rolling machine. Cal/OSHA, the state job safety agency, cited the company, JSL Foods Inc., for willful violations because an almost identical accident had happened before.

The Consumer Product Safety Commission is struggling to contain the fallout from a data breach involving thousands of companies, highlighting the tension between the agency’s mandate to protect consumers and to prevent reputational damage to product makers.

Last August, Higinio Romero was working on the roof of a condo in South Florida when he slipped and fell two stories, landing on rocks below. Emergency workers found him unconscious and bleeding from his ears. Romero — a father of two children, 4 months old and 10 years old — died about an hour later. According to a sheriff’s report, he had unclipped his safety harness shortly before the fall.

Since the early 1980s, the Consumer Product Safety Commission has conducted a grim census, tracking reports of deaths from crashes of all-terrain vehicles, or ATVs. Now the body count has risen above 15,250, according to the agency’s latest annual report, with more than one in five of the deaths suffered by children under 16.

After a Florida driver was killed in a crash in 2016 while his Tesla was in “Autopilot” mode, regulators assured the public that Tesla’s autonomous driving system was safe. An investigation by the National Highway Traffic Safety Administration (NHTSA) found that after a key component called Autosteer was added, crash rates in Tesla cars had dropped.

A requirement that employers disclose more information about worker injuries to safety officials and the public has been scaled back by the Trump administration. The Labor Department action, reflecting the administration’s broad push to ease regulations on business, weakens an Obama-era initiative to improve safety enforcement and crack down on underreporting of job injuries. The 2016 rule, which had been hailed by safety advocates, drew the ire of the U.S. Chamber of Commerce and other business groups.

A chickenpox outbreak at a private school in North Carolina drew extensive national news coverage in November. The thrust of most stories was the public health threat of unvaccinated children and superstitious beliefs about vaccine risks.

As the dim early light washed over the Appalachian countryside, Jason Kingsley began his climb up the side of an 80-foot silo. Kingsley was not a morning person. But he was also broke and unemployed. So when a dairy farmer named Ronald Wood called to ask him to help to rescue a piece of machinery that had accidentally been buried under tons of hay and legumes, Kingsley said yes.