HAYWARD -- Parents can get their children's blood tested for lead at the Rock the Lot Health Jam next week in South Hayward.

The testing on Aug. 15, part of the county's Healthy Child initiative, is available to children under 6. Children in that age group are more susceptible to lead poisoning, which can cause learning disabilities, because they often put things in their mouths, said Betty DeForest of South Hayward Parish, sponsor of the fair.

Samples of each child's blood will be taken by representatives of the county's Healthy Homes Department and sent for testing. After four to six weeks, families are notified of the results, said Patricia Garcia, county Healthy Child Initiative manager.

Blood tests are the only way to detect lead poisoning, which has no obvious symptoms, she said.

If high levels of lead are found, the county will work with the family to figure out where the exposure is coming from and remove it, said Julie Kurko, Health Homes health services manager. In addition to lead-based paint in older homes, other culprits could include toys, especially ones from China; pottery; and even vinyl purses.

The fair also will offer free basic medical services such as blood pressure checks and diabetes screening, plus information about available community resources.

Medi-Cal representatives will be there to help people sign up. Children's activities and free giveaways are planned.

The fair runs 3 to 7 p.m., Aug. 15 at Westminster Hill Outreach Center, 27287 Patrick Ave.