
In checking with area county road departments, slag is not used on area secondary roads. Winnebago County Engineer Scott Meinders confirmed the non-usage.
Slag is a byproduct of steel manufacturing, and contains metals at levels that are harmful to infants and toddlers but also for people up to 18 years old, the report said.
Children exposed to high levels of manganese could experience learning disabilities and adverse behavioral changes, according to a U.S. Department of Health report.
Slag dust is also dangerous for adults who are exposed to levels nearly twice what’s considered safe, though adults would have to work “an entire workday, most days of the year,” to be harmed, the report said.
People exposed to high manganese levels can experience mild neurological damage that could lead to confusion, balance issues and coordination problems, Schmitz said. The effects would be temporary and likely wear off once a person is no longer exposed.
Slag is cheaper than gravel and has saved Muscatine County, for example, an estimated $1 million, according to officials. The county had previously relied on two decade-old state reports to show that the material was safe.