Mango Materials, of Berkeley, CA, makes the biopolymers PHA (Poly-hydroxyalkanoate ) and PHB (poly-hydroxybutryate) from waste methane. The Mango team was challenged to investigate colorants because while PHA is biodegradable, many of the substances added to it for application performance are not and some of the currently used industrial colorants have properties that are cause for concern. Iron oxide red, for example, is persistent in the environment and has shown evidence of carcinogenic effects.
The Mango team researched several areas in...