On 11 November 2015, the Brazilian Foreign Trade Council (Camex) issued Resolution no. 109 increasing the import tariff on acrylic acid and sodium polyacrylate. The goods are classified under the following Mercosur Common Nomenclature (NCM):

• acrylic acid, NCM 2916.11.10: from 2% to 10%
• sodium (poly)acrylate, NCM 3906.90.44: from 2% to 12%

 
List of Exceptions to the Common External Tariff
The tariff codes were included in the List of Exceptions to the Common External Tariff (LETEC) of Mercosur, which is a mechanism that allows member states of Mercosur to apply customs duties that are lower or higher than otherwise listed in the Mercosur Common External Tariff schedule.
 
However, the tariffs shall not surpass the ceilings given by the WTO. Mercosur Decision CMC no. 26/15 gives Brazil the right to maintain a list of 100 codes based on the Mercosur Common Nomenclature until 31 December 2021.
 
Due to this restriction, Brazil had to retrieve two other goods from the LETEC, which were NCM 2915.40.10 (monochloroacetic acid) and NCM 2933.69.22 (Hexazinone).
 
The new tariffs took effect on 12 November 2015.

Update
On 25 October 2018, the Brazilian Foreign Trade Council has adopted Resolution 82 revoking 124 resolutions including this one.