SAO PAULO, Aug 21 (Reuters) - Brazil's biosafety regulator CTNBio has approved the use of Bayer's (BAYG.DE: Quote, Profile, Research, Stock Buzz) genetically modified cotton seed, which is tolerant of the herbicide glufosinate ammonium, the regulator and the company said on Thursday.

The seed must still be approved by the Latin American country's Agriculture Ministry before it can be planted.

Within the CTNBio's decision-making committee, 18 members voted in favour, three against and two abstained.

Any objections to the decision must be raised within 30 days, and would be examined by the National Biosafety Council, which comprises representatives from 11 government ministries.

CTNBio's decision was its first approval of a genetically modified crop since September 2007, when it approved Syngenta's (SYNN.VX: Quote, Profile, Research, Stock Buzz) pest-resistant Bt11 corn.

Several genetically modified crops are already planted in the agricultural powerhouse, including herbicide-resistant soy and pest-resistant cotton. Genetically modified corn already approved in Brazil could be planted on some farms next season. (Reporting by Roberto Samora; Writing by Peter Murphy; Editing by Walter Bagley)