Complex sentence: The tonic was eventually exposed as a lethal blend of cocaine, acetanilid, and alkaloid botanicals, and was the cause of uncounted addictions and deaths, including that of Hezekiah's wife and Antoine's mother, Constance Leng Pendergast.
Split into simpler sentences: The tonic was eventually exposed as a lethal blend of cocaine, acetanilid, and alkaloid botanicals. It was the cause of uncounted addictions and deaths, including that of Hezekiah's wife and Antoine's mother, Constance Leng Pendergast.