For all practicality, the research points that this reed is the same material you import for production of duduk reeds. From Wikipedia.org "Arundo donax was introduced from the Mediterranean to California in the 1820s for roofing material and erosion control in drainage canals in the Los Angeles area (Bell 1997; Mackenzie 2004). Through spread and subsequent plantings as an ornamental plant, and for use as reeds in woodwind instruments, it has become naturalised throughout warm coastal freshwaters of North America, and its range continues to spread." which indicates the use for woodwind instrument reeds. And, also "The stem material is both strong and flexible. It is the principal source material for reeds for woodwind instruments such as the oboe, bassoon, clarinet, and saxophone. It is also often used for the chanter and drone reeds of many different forms of bagpipes. Giant reed has been used to make flutes for over 5,000 years. The pan pipes consist of ten or more reed pipes". You are correct in that the Arundo donax, Giant Cane, does have the ability to uptake certain heavy metals and other undersirable pollutants into it's stem, so getting a source in clear water and streams would certainly be prudent. It does, however and more importantly where ever it is grown, also uptakes silica, and would depend on the amount of silica availabe in the soil, but it is what gives it some attributs to NOT be used as fodder for forage animals like cattle, and sheep since it (silica) can become a toxic accumulation in the stems. These plants seem to have a unique ability to survive and thrive even when introduced outside their native habitat. This is what makes them so problematic in areas such as America, in that they really grow well, and have developed ways to keep 'their kind' well established in the world. Since they do not repoduce from seeds, the DNA transfers to each plant in an amost exacting match from plant to plant. Quite similar to the way that certain clone of Vitis vinifera, (wine grapes) have been carefully and systematically repoduced in 'like kind' from their origins in Germany, Fance, Spain and Italy to parts of the United States as well as other countries around the world. Through DNA testing and more specifically, in testing certain DNA markers within the range, we have isolated what we once only knew as Zinfandel in this country to have actually come from a vine in Croatia so many years ago. It's secret lost in the shuffle of plant material brought here so many years ago, now brought to light. Zinfandel is Crljenak from Croatia. BTW, I work as a winemaker in the wine industry here in Michigan, so cloning and plant specifis in DNA are a facinating study to me.