(Bloomberg) -- For two decades, Brazil’s unique solution to curb tailpipe emissions — specialty cars powered by any mix of gasoline and ethanol — helped it boast a fraction of the roadway pollution of other countries its size. Now, it threatens to hold it back.Most Read from BloombergA $500 Billion Corporate-Debt Storm Builds Over Global EconomyApple Tests ‘Apple GPT,’ Develops Generative AI Tools to Catch OpenAIIn London, New York and Paris, a Giant Office Bet Is Going WrongTesla Investor Rode