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Glasshouse and field studies showed that Vetiver grass can produce high biomass (>100t/ tha(-1) year(-1)) and highly tolerate extreme climatic variation such as prolonged drought, flood, submergence and temperatures (-15 degrees - 55 degrees C), soils high in acidity and alkalinity (pH 3.3-9.5), high levels of Al (85% saturation percentage), Mn (578 mg kg(-1)), soil salinity (ECse 47.5 dS m(-1)), sodicity (ESP 48%), anda wide range of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). Vetiver can accumulate heavy metals, particularly lead (shoot 0.4% and root 1%) and zinc (shoot and root 1%). The majority of heavy metals are accumulated in roots thus suitable for phytostabilization, and for phytoextraction with addition of chelating agents. Vetiver can also absorb and promote biodegradation of organic wastes (2,4,6-trinitroluene, phenol, ethidium bromide, benzo[a]pyrene, atrazine). Although Vetiver is not as effective as some other species in heavy metal accumulation, very few plants in the literature have a wide range of tolerance to extremely adverse conditions of climate and growing medium (soil, sand, and railings) combined into one plant as vetiver. All these special characteristics make vetiver a choice plant for phytoremediation of heavy metals and organic wastes.

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Dense gas techniques, which utilize the properties of fluids in the vicinity of the critical point, are increasingly being used for the processing of pharmaceuticals. Dense gases are unique solvents that can be used for extractions, chromatographic separations, and chemical syntheses because of their liquidlike solvation power and gaslike mass-transfer properties. The processes can be conducted at moderate temperatures and are thus suitable for many heat-labile compounds such as proteins, biocompatible polymers, and pharmaceuticals. The products formed by densegas processes are generally free of residual solvent. Recent applications of dense gas techniques have focused on micronization; crystallization of high-purity particles; sterilization; and drug formulations, including the formation of liposomes and drug coatings. The following review presents examples of drug extraction, separation, synthesis, sterilization, and particle formation and demonstrates the broad application of dense gases for drug formulation purposes in the pharmaceutical industry.