Laundered Shop Towels Expose Printers to Heavy Metals

Of the 29 metals studied, 26 were found on more than 90% of the towels tested.

Gradient, a Cambridge, MA-based environmental- and risk-science consulting firm published a study that finds elevated levels of heavy metals in tested and laundered shop towels. The study, “Evaluation of Potential Exposure to Metals in Laundered Shop Towels,” builds up an earlier analysis published in 2003 and concludes that, even after commercial laundering, the towels studied retain elevated levels of metals. This could result in printers being exposed to levels that exceed agency guidelines, which are based on various health problems, such as cancer.

Commissioned by Kimberly-Clark Professional, Gradient researchers analyzed data from laundered shop towels submitted by 26 North American companies across various manufacturing industries including a large number of printers. The towels were submitted to an independent lab for testing. Gradient found significantly higher levels of contamination than in the similarly designed study from 2003.

The findings include the following: A worker using a typical number of laundered shop towels a day (12) may be exposed to levels of antimony, beryllium, cadmium, cobalt, copper, lead, and molybdenum that are higher than health-based guidelines set by regulatory agencies. They also found that the concentrations of six metals—aluminum, barium, calcium, copper, magnesium, and sodium—were found to be significantly higher than towels tested in the original 2003 Gradient study. A wider variety of heavy metals were commonly found on the shop towels tested. Of the 29 metals studied, 26 were found on more than 90% of the towels tested. To get a copy of the latest report, visit

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