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Related Experiment Video

Updated: Jun 26, 2026

Building a Simple and Versatile Illumination System for Optogenetic Experiments

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Published on: January 12, 2021

Lead in Christmas lights.

Joseph Laquatra¹, Lelia M Coyne, Mark R Pierce

¹Cornell University, Department of Design and Environmental Analysis, Ithaca, NY 14853-4401, USA. JL27@cornell.edu

Journal of Environmental Health

|January 1, 2009

Summary

This summary is machine-generated.

Lead was detected in Christmas light strings, with surface levels exceeding safety standards. Further research is needed to understand potential health impacts from this lead exposure.

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Area of Science:

Environmental Science
Toxicology
Consumer Product Safety

Background:

Lead is used as a stabilizer in Polyvinyl Chloride (PVC) jacketing for Christmas light conductors.
Public awareness of lead in consumer products has increased.

Purpose of the Study:

To quantify accessible lead levels in various Christmas light sets.
To assess surface lead concentrations against established safety benchmarks.

Main Methods:

Researchers collected wipe and total lead content samples from new and old Christmas light sets.
Samples were analyzed using procedures aligned with U.S. Environmental Protection Agency (U.S. EPA) Lead Inspectors' protocols.
Lead content was measured and normalized to string length and estimated surface area.

Main Results:

Lead was present in all tested Christmas light samples.
Surface lead concentrations on some samples exceeded the U.S. EPA's clearance level for residential surfaces.
Cornell University's later analysis of Nebraska samples showed diminished lead quantities, suggesting potential degradation or transfer.

Conclusions:

Christmas lights can contain significant surface lead, potentially posing an exposure risk.
There are currently no established standards or testing protocols for lead content in Christmas lights.
Consumers should exercise caution to minimize potential lead exposure from Christmas lights.