The state Department of Public Welfare is investigating a day care center in Fayette County after receiving complaints that staffers gave children pickling salt containing a potentially toxic compound to discipline them.

Five employees of the YMCA Child Development Center in South Connellsville, including its director and child care providers, were suspended without pay yesterday for "not following proper discipline procedures," said Steven Simon, executive director of the Regional Family YMCA of Laurel Highlands.

Stacey Witalec, the welfare department's spokeswoman, said the complaint from a parent indicated that five children were being given alum "as a disciplinary measure."

Mr. Simon confirmed that the substance in question was alum pickling salt and was given as "punishment for misbehaving."

Alum can cause nausea, vomiting, abdominal pain and burning, and it is corrosive upon ingestion, according to the federal Centers for Disease Control and Prevention.

One parent, who requested anonymity, said he learned from another parent Wednesday that his 3-year-old son was one of the children given alum.

"I asked my son, 'When you get in trouble, what happens?' And he said, 'They put powder in my mouth.' And he named the director," the parent said.

The parent said the incidents came to light when two day care teachers witnessed alum being given to children and called a child-abuse hot line. One of those teachers then contacted at least one of the parents whose child had been disciplined.

When he learned of the alum, he said, he contacted the county Children and Youth Services.

His son, he said, seems to be fine now. But looking back, he said, there might have been warning signs.

"He complained about his stomach being upset," the father said, "but he played normally, so we figured it was like a 'cry wolf' thing."

Alum, or ammonium aluminum sulfate, is an odorless, white crystal or powder found in several household products including some baking powder and styptic pencils. It is an astringent and is also used in pickling, paper-making, tanning, waterproofing and fireproofing.

The danger posed by any alum ingested by children would depend on the amount swallowed and its concentration, Dr. Edward P. Krenzelok, director of the Pittsburgh Poison Center, said.

"A little exposure is no big deal," Dr. Krenzelok said. "My guess is a pinch would be inconsequential unless it's a high concentration."

But a large enough dose at the right concentration could prove fatal.

"If someone got a teaspoonful of alum, that would not be a good thing. You could have vomiting, you could have diarrhea, you could have some pretty serious irritation to the inside of the mouth," Dr. Krenzelok said.

Details of the investigation were not released. Ms. Witalec said she did not know over what period of time the abuse was alleged to have taken place, how much alum was said to have been given to the children, or how old the children were.

"We'll be going out to the facility doing interviews with the staff as well as doing different on-site investigations, seeing what we can find and if the complaint can be verified," Ms. Witalec said. "I can assure you with a complaint as serious as this we will be leaving no stone unturned."

The child development center is licensed for up to 100 children.

"The staffers involved in this situation had been thoroughly investigated and had, to the best of our knowledge, served the YMCA and the Connellsville community responsibly," Mr. Simon said in a statement,

Mr. Simon said the child care center continues to operate.

"We are open and we are taking care of children the best that we are able to do," he said.