For more than two months, we have been on point to learn everything we can about a St. Joseph tannery’s waste product implicated as a suspected cause of brain tumors and other health problems.

We know much more now than we did that first day, April 22, when the suspicions were raised in a lawsuit. We even allowed ourselves to breathe a cautious, tentative sigh of relief upon hearing that studies so far have not found a health risk from the tannery’s sludge that was spread on fields as a fertilizer.

And still, we want and need to know more. It’s important to us, and it’s important to thousands of others throughout Northwest Missouri.

That’s why we strongly endorse the continuing investigation by the U.S. Environmental Protection Agency, the Missouri Department of Natural Resources and the Missouri Department and Health and Senior Services.

The sludge ultimately may be proven to be safe to humans in every application. However, establishing this as fact is no small chore. Investigators have identified 773 distributions of sludge to 116 Northwest Missouri farmers over a 25-year period, ending in 2008; the first round of testing involved only eight soil samples from three farms.

The testing did detect the presence of the chemical of concern, hexavalent chromium, which has been shown to cause some forms of cancer. But so far the testing has found the chemical only in amounts well below the normal standards for closer investigation.

The next round of tests — involving the collection of soil samples from 15 additional parcels of farm land — clearly is warranted because the initial tests were so limited. Beyond this next round, we’ll see.

Our pursuit of definitive answers about the sludge runs parallel to the quest of those who have brought forward concerns about brain tumors in and around Clinton County. Residents with a vested interest in either topic should make every effort to attend the public forum scheduled for 6:30 to 9 p.m. Tuesday in the Fulkerson Center on the Missouri Western State University campus.

We would do well to remind the scientists and government officials leading these probes how much we care about their findings.