* Seven ethanol companies fined for slave labor since 2016 * Firms are part of Brazil's fuel decarbonization program * Government says scheme does not address labor issues By Fabio Teixeira RIO DE JANEIRO, Oct 26 (Thomson Reuters Foundation) - W hen manual laborer Alison Moreira dos Santos moved across Brazil for a job on a sugarcane plantation in the southeastern state of Minas Gerais in March, he expected to work hard. Just over a month later, the 35-year-old was dead.