The provocative creators of 42 Below vodka have done it again with their new skincare range: they've sparked formal complaints with an in-your-face billboard of a naked woman mounted on a white horse.

The vodka company was ticked off by the Advertising Standards Authority (ASA) after an advertisement that depicted Maori trading vodka for blankets and muskets.

Founder Geoff Ross and his business partners sold the vodka company a few years later for $138 million, boasting on the website: "We are totally f***ing loaded."

Now, Ross' new Ecoya skincare company is up before the ASA for a billboard that critics describe as "sexually provocative".

The billboard, one of three Ecoya erected last month in Auckland and Wellington to promote their natural skin care products, has elicited three formal complaints.

Family First national director Bob McCoskrie said the billboard, on Auckland's Fanshawe St, was unacceptable as it could be seen by children. "There is a sexually provocative undertone to it, I think, that is what makes it cross the border and the boundary of public decency.

"The fact of the matter is they [children] are being forced to be more open to it ... Should we be protecting their moral innocence, does it matter if we sexualise everything? What harm is that doing?"

McCoskrie called for a vetting system that would give families a voice, and stronger community and family representation.

But ASA chief executive Hilary Souter said: "I think the complaints process is robust ... we uphold half of the complaints that go to the board and as soon as a complaint is upheld they are withdrawn."

Ecoya marketing manager Donna Marris said the company was proud of the images, describing them as tasteful and effective. "We don't expect everyone to respond in the same way, but what it's about is delivering clear and beautiful skin and this image shows a nourished body in a tasteful way," she said.