The prefix "nano" means 1/1,000,000,000 = 1e-9, so 1,000,000,000 ng = 1e+09 ng = 1 g. 1 ng = 1,000 picograms. 1000 ng = 1 microgram. 1 ng = 1e-12 kg. This unit, along with picogram, femtogram, attogram and zeptogram are unlikely to ever appear on an MSDS!