Why is calcium carbide, used to ripen fruits, harmful?

The use of calcium carbide for the artificial ripening of fruits is banned in India. According to the Ministry of Health and Family Welfare, calcium carbide releases acetylene gas, containing harmful traces of arsenic and phosphorus. These can cause serious health issues such as dizziness, frequent thirst, irritation, weakness, difficulty in swallowing, vomiting and skin ulcers, among others.