Lead is widespread in municipal solid waste throughout the United States. The sources
for the lead are numerous, although lead-acid storage batteries are the biggest culprit by far. According
to the EPA, in 1995 lead acid storage batteries accounted for 64.7% (by weight) of the lead in the waste stream.
The second biggest source of lead in municipal solid waste is from Cathode Ray Tubes (CRTs), which accounted for
28.56% of the waste stream lead in 1995. CRT waste contribution was expected to increase to 30% by the the
year 2000, due to the rapidly escalating number of consumer electronic devices that are thrown away each year.
CRTs are the major component of television screens and computer monitors, with the lead confined
predominantly to the neck and funnel of the CRT. When CRTs are disposed of in landfills, lead and other heavy
metals can leach into groundwater. When CRTs are incinerated, the ash can become contaminated with the heavy
metals causing further disposal problems. The leachability of lead in CRTs is determined by the Toxicity
Characteristics Leaching Procedure (TCLP), a general method to examine whether a solid leaches hazardous pollutants.
The regulatory limit for for TCLP lead is 5.0 mg/L.
Over 10 weeks, televisions and computer monitors were collected from individual donations,
electronics repair facilities, an electronics manufacturer, and institutional electronics disposal. A total
of 36 models of CRTs were obtained and tested, with 15 of these exceeding the regulatory limit of lead. In
the study, researchers used the TCLP to identify the leachable concentration of lead in the neck, funnel and face.
In this data set we list the weighted average that was obtained (weighted by fractional mass). Several models
of CRTs had a (weighted) leachable lead concentration reported as <1.0 mg/L; we converted these figures to 1.0
mg/L for data analysis purposes.
Source: "Characterization of Lead Leachability from
Cathode Ray Tubes Using the Toxicity Characteristic Leaching Procedure",
Townsend, T.G., 1999, University of Florida and the Florida Center
for Solid and Hazardous Waste Management.