A new study aims to discover whether toxic mould in homes is making people sick.

A Wellington-based University of Otago research team's been granted funding of $1.2 million for the research.

It will look at whether there's an association between toxic mould in homes and respiratory problems.

Lead researcher Julian Crane told Mike Hosking little is known about the impact of the toxic moulds.

"We have a lot of data on mould. Studies that have looked at people who live in mouldy houses and health and we know that they are more likely to have breathing problems and generally feel unwell but we don't know why."

LISTEN ABOVE AS JULIAN CRANE SPEAKS WITH MIKE HOSKING