New Jersey joins Louisiana and North Carolina in prohibiting state DOT and tollway authorities from using paint mixed with reflective glass beads; and 22 other states have adopted bid specification requirements developed and approved by the American Association of State Highway Transportation Officials last August.

At least two studies show that imported glass beads contain increasingly higher levels of arsenic and lead that quickly leach when exposed to groundwater and normal environmental conditions. U.S. manufacturers use environmentally friendly recycled flat glass, but overseas producers — particularly those in emerging nations, according to the American Glass Bead Manufacturers' Association — use glass that required chemical modification, resulting in products with high levels of the toxins.

China, for example, regulates heavy metals for domestic use but continues to export contaminated products made from old glass.