Kava lateral roots have the highest content of kavalactones in the kava plant. Kava prepared as described above is much more potent than processed kava. In Australia, the supply of kava is regulated through the National Code of Kava Management. Kava root extract exports also have become important. Clinical trials of kava have not revealed hepatotoxicity as a problem. The average elimination half-life of kavalactones typically present in kava root is 9 hr. Fresh, undried kava produces a stronger beverage than dry kava. In Vanuatu, exportation of kava is strictly regulated. This has been confirmed by further studies evaluating the toxicology of kava drink. Tongan, Niue, Rapa Nui, Tuamotuan, and Rarotongan "kava"; Samoan and Marquesan "ava"; and Hawaiian "awa". In particular, production of copra and kava create substantial revenue. Muslin is used when making traditional Fijian Kava as a filter. Kavalactones are a class of lactone compounds found in the kava shrub. Fresh kava root contains on average 80% water.