Cleveland, Ohio -- The history of lead stretches back at least as far as the Roman Empire, which first used the metal to carry water in pipes.
Here's a more recent history:
1904: Lead is first scientifically linked to the poisoning of a dozen children exposed to flaking paint in Australia in 1892.
1920s: General Motors experiments with adding a lead mixture -- tetraethyl lead-- to gasoline.
1922: The League of Nations, the precursor to the United Nations, bans lead-based paint. The United States declines to sign on.
1924: At least 15 workers producing the gas additive die in New Jersey and Ohio and many others fall ill.
1925: The U.S. Surgeon General temporarily suspends adding lead to gasoline but the ban is later lifted.
1962: Cuyahoga County Coroner Dr. Samuel Gerber starts investigating lead deaths in local children along with researchers at what was then Western Reserve School of Medicine. The deaths of at least 19 children between 1952 to 1959 were attributed to lead poisoning.
1970: Cleveland Mayor Carl B. Stokes testifies before the U.S. Senate Committee on Labor and Public Welfare about the impact of lead poisoning in Cleveland. He tells the committee it costs about $300 to abate a home of lead and approaches $275,000 for the lifetime care of a brain damaged child.
1971: The Cleveland Health and Welfare Department receives a $700,000 federal grant to start a comprehensive lead poisoning prevention and control program.
1972: Using federal grants for screening, the city defines its "lead belts" with the highest rates of lead poisoning in the Hough/Norwood neighborhood and the Near West Side/Tremont neighborhoods. At the time, Dr. Jack Wilt, the chief of the city's environmental unit, oversaw testing of 10,000 children.
Jan. 12, 1973: Mayor Ralph Perk launches a five-year, citywide program to screen children for lead poisoning.
Nov. 28, 1973: The Environmental Protection Agency releases a study that confirms lead from automobile exhaust is "posing a direct threat to public health."
1974: Federal phase-out of leaded gasoline begins.
1978: Federal ban on lead-based paint for residential usage begins.
1988: The Lead Contamination Control Act of 1988 authorizes the Centers for Disease Control and Prevention to create programs to eliminate childhood lead poisoning.
August 3, 1990: President George Bush announces that "first dog" Millie, an English springer spaniel, was poisoned by lead during renovations to the White House. Bush calls her illness a "terrible thing."
1991: The Centers for Disease Control and Prevention (CDC) recommend universal screening for blood lead levels and lowers the level of concern for children from 25 micrograms per deciliter to 10 micrograms per deciliter.
1992: Mayor Mike White responds to criticisms about the city's lack response to health department reports that reveal that 86 percent of young children tested in the Glenville neighborhood had high lead levels. He calls for more federal resources.
1992: Congress passes the Residential Lead-Based Hazard Reduction Act Title X to help protect young children and families from exposure to lead in paint, dust and soil.
1996: EPA's full phase-out of leaded gasoline complete.
1998: The CDC surveys 19 states to determine the level of childhood lead poisoning. Ohio has the second-largest percentage of children who test positive. Cuyahoga County has the highest percentage among all the counties surveyed.
1999: HUD rejects Cleveland's proposal for a $3 million lead hazard reduction grant due to a poor record of using the money to abate homes under a $5.5 million federal grant awarded Cleveland in 1995. The city had contracted to reduce lead hazards in 600 dwelling units, but a March 1998 snapshot of the city's progress showed only 11 dwelling units had been completed.
2003: A Plain Dealer series titled "Children Left Behind" finds that Cleveland has the 2nd highest rate of lead poisoning of 10 cities with comparable demographics.
July 19, 2005: Mayor Jane Campbell kicks off a lead awareness week press conference celebrating the progress made. She says the number of lead poisoned kids has declined 47 percent from 1994 to 2004.
2007: The 70-member Greater Cleveland Child Lead Advisory Council asks more than 1,200 doctors and clinics throughout Cuyahoga County to track children whose lead levels are within the legal limit but are still considered dangerous by some clinicians. County officials who push for the added intervention hope it can increase screenings -- particularly in the suburbs, where little testing is done -- and possibly spark a movement to change national childhood lead poisoning guidelines. Screening rates don't change but the lower level of concern is later adopted.
2010: The Centers for Disease Control and Prevention, HUD and the Environmental Protection Agency support a national goal of eliminating childhood lead poisoning by 2010.
Jan. 4, 2012: The CDC's Advisory Committee on Childhood Lead Poisoning Prevention says dealing with the housing of children only after they have an elevated blood lead level "should no longer be acceptable practice."
January 2012: Cleveland is stripped of the remainder of a $2 million federal grant for cleaning hazardous lead paint and dust from homes because officials fail to spend the federal money in a timely manner. HUD also demands that the city transfer management of the program from the Department of Public Health to the Community Development Department in order to spend the remaining million.
2012: The CDC lowers the "level of concern" for lead in children's blood from 10 to 5mg/dL
August 2013: HUD rejects Cleveland's application for a $3 million grant to reduce or remove lead paint and dust from more than 200 homes.
September 2015: HUD awards both Cuyahoga County and Cleveland with lead grants of more than $3 million.