Litko now has new toxic flame markers. That is to say, markers to use when marking toxic flames. They’re not flame markers that are, themselves, toxic.
From the release:
New Toxic Flame Markers are usable in Sci-Fi and fantasy gaming, or anywhere you need unusual colored flames.
Small set: 7 small markers
Medium set: 5 medium markers
Large set: 3 large markers
Variety set: 1 lg, 2 med, 2 sm mkrs