Nigeria’s government defied private-sector opposition to impose a new “sin tax” on Monday amid fears that growing tobacco and alcohol consumption could threaten a public health crisis.

Ignoring a last-minute legal challenge, the country’s finance ministry announced that a rise in excise duties had finally come into force, three months after Muhammadu Buhari, the president, was forced by public opposition to delay the hike.

With Nigeria emerging from a painful recession, the new duties will help both to boost revenues and reduce the exchequer’s dependency on the oil sector.

But health campaigners also hope that the taxes will begin to reverse the increasingly deadly habits of a growing number of their countrymen.

Nigerians are Africa’s biggest drinkers, consuming 12.28 litres of alcohol a year per head, according to industry figures. Alcohol consumption is also rising faster in Nigeria than anywhere else on the continent.

Alcohol dependency has led to a rise in non-contagious diseases and has done much to contribute to Nigeria’s grim road safety statistics, medical experts say. Nigeria’s roads are among the most dangerous in Africa, with fatality rates nearly double the global average.