More than a month has passed since Freedom Industries Inc. reported a disastrous chemical spill into West Virginia’s Elk River on January 9, prompting a state of emergency and restricting 300,000 people from drinking or using their own tap water.

West Virginians, understandably concerned about a potential public health crisis, have pressed hard for answers. In return, they’ve faced a series of confusing statements and contradictions from state and federal officials. The story is moving so quickly, it can be tough to keep up and parse out what we actually know. Here’s an update of where we are now:

Officials are still sending mixed messages regarding water safety.

The Center for Disease Control and local health departments, along with West Virginia American Water, all maintain that the water is safe to use. They’ve based their assessment on a controversial “screening level” of less than 1 part per million (ppm) of MCMH for safe water usage (more on this later). Samples from treatment plants have met that criterion, though the state still hasn’t conducted planned tests on home plumbing systems.

Recent statements from other officials weren’t so definitive. State Health Officer Dr. Leticia Tierney told the House Transportation and Infrastructure Committee on Monday, “Everybody has a different definition of safe.” In that same hearing, US Chemical Board Chairman Rafael Moure-Eraso said the dearth of knowledge about crude MCHM and PPH means we can’t say outright whether the water is safe.

After the state cleared some residents to use their tap water, the West Virginia Department of Health and Human Resources (DHHR) posted a notice based on CDC recommendations advising pregnant women to drink bottled water instead. The CDC recently approved water usage for all West Virginians, including pregnant women, although the advisory remains posted on the DHHR website.

We still know very little about MCHM.

The Charleston Gazette-Mail has a stunning report about how government scientists rushed to determine the widely cited standard of 1 ppm of MCHM. In short, the CDC determined a chemical safety standard for 300,000 West Virginians the night of the spill’s discovery, based on a chemical manufacturer’s 1994 tests on lab rats. The CDC has since changed its tune, now citing an earlier study by the same company with higher standards. But some experts have criticized both studies—neither peer-reviewed nor publically available—as inadequate for making human health conclusions that affect so many people.

We’ve learned very little since then, and we still don’t know the long-term human health effects of MCHM exposure.

At least five schools have dismissed students over chemical odors.

At least five schools sent students home last week after administrators detected the “licorice-like” odor associated with MCHM on school grounds. One teacher fainted and was sent to the hospital because of the odor. There were also complaints of lightheadedness, burning eyes and burning noses, all symptoms related to MCHM exposure.

The odor itself has become a standard for residents who are wary of the state’s water safety assurances. “If one smells the odor, people know the chemical is in the water,” Dr. Rahul Gupta, director of the Kanawha-Charleston Health Department, told The New York Times. “It’s difficult for a lot of people to drink it even if they agree with the science behind it.”

The storage facility in question fell short of federal standards.

Monday’s congressional hearing revealed that, just three months before the spill, private inspectors found Freedom Industries’ storage tanks to be lacking in “full compliance” with EPA standards.

But Moure-Eraso said during the hearing that the consultants did not inspect the tank that leaked MCHM because it considered the chemical “nonhazardous.” A representative from the consulting firm chose not to give additional details about the review. Though invited, no one representing Freedom Industries attended the hearing.

The spill raises serious questions about regulatory oversight.

For one, West Virginia law doesn’t require inspection of chemical storage facilities. Reports show federal inspectors hadn’t checked Freedom Industries’ site since 1991.

The spill also revealed potential holes in federal regulation standards for chemical storage. In Monday’s hearing, Moure-Eraso noted that the faulty tank’s location “just upstream of the water intake was a historical anomaly that had tragic consequences.” He recommended stricter limits on where chemical storage facilities are built.

The disturbing lack of knowledge about MCHM has led to criticism of the our chemical safety laws. Because MCHM was one of 64,000 chemicals grandfathered in with the Toxic Substances Control Act of 1976, companies do not have to test or confirm its safety before use. Some critics, including the Washington Post’s editorial board, say this approach is completely outdated.

“We can’t just point a single finger at this company,” Angela Rosser, executive director of West Virginia Rivers Coalition, told The New York Times. “We need to look at our entire system and give some serious thought to making some serious reform and valuing our natural resources over industry interests.”