WASHINGTON - A machete knife left near an outdoor play area. Household chemicals accessible to preschoolers. Widespread failures to conduct criminal background checks of employees.

These violations and others were found at Head Start centers across the country, according to a report released Tuesday by the Inspector General of the Department of Health and Human Services.

Head Start is the federal program with roots in President Lyndon Johnson's War on Poverty that today provides early-education services to nearly one million poor children nationwide. The federal government gives grant dollars to public, nonprofit, and for-profit programs to provide the services.

Other safety violations found at the centers include a screw protruding from a bookcase at child-height level in Longmont, Colo.; a children's bathroom in Edna, Texas, without lighting for months; and expired infant formula found in the refrigerator in the District of Columbia.

The Inspecter General's review was compiled using 24 audits of Head Start grantees running 175 facilities in eight states from May 2009 to October 2010. While the review was a fraction of the approximately 1,600 Head Start grantees, it still raises red flags about the safety of children in such programs.

All told, the review found:

Twenty-one of 24 grantees did not comply fully with federal Head Start or state requirements to conduct criminal and other background checks.

Nearly 90 percent of the facilities had toxic chemicals such as markers labeled "keep out of reach of children" and cleaning supplies accessible to children.

More than 70 percent had open or broken gates leading to parking lots, streets, or unsupervised areas and inadequate or broken fences.

More than half had playground equipment that was not in good repair, with problems such as protruding bolts, broken climbing apparatuses, and elevated platforms without protective guards.

The inspector general recommended that the Administration for Families and Children, which falls under HHS and oversees Head Start, conduct on-site monitoring to ensure that centers comply with health and safety regulations.

It also called for the agency to determine whether it should seek legislation to require periodic background checks for Head Start employees. It also suggested policies to require that employees be disqualified or terminated if they have been convicted of sexual abuse of a child or other forms of child abuse.

In response, Families and Children said it "takes health and safety regulations very seriously."

Of the 24 grantees audited, three have since had Head Start dollars revoked, while others corrected the deficiencies, Families and Children said. It also said it was reviewing the suggested policy changes.

Ensuring quality in Head Start programs has been an ongoing issue.

Last month in Yeadon, Pa., President Obama called Head Start "an outstanding program and a critical investment," but he said more accountability was needed.

Under new rules that he announced, lower-performing Head Start programs must compete for funding if they have deficiencies discovered in their on-site review or do not meet other standards.

In most cases, the centers said in letters included in the audits that they had taken action to fix the problems found.