China National Chemical Corp. said it filed for US antitrust approval with the Federal Trade Commission for its proposed $43 billion takeover of Swiss agrochemical company Syngenta AG. ChemChina has submitted documentation required by the Hart-Scott-Rodino Act and expects the US antitrust process to be “on track,” the company said in an e-mail. The FTC, which oversees merger reviews along with the Justice Department, generally has 30 days to clear the proposed tie-up or issue a second request, seeking more information and a longer review period. When it’s a cash tender offer, the FTC has 15 days to review. According to Bloomberg, the proposed transaction already has been cleared by a US national security panel and won antitrust approval in Australia, where there are overlapping products between Syngenta and ChemChina’s Israeli-based generic agrochemical maker Adama.