Impax Asset Management, the UK-listed equity fund management firm focusing on environmentally-themed investments, said its assets under management increased 22 per cent  from £1.8 billion ($2.7 billion) to £2.2 billion in the six months to 31 March from October 2012, reflecting net inflows of £100 million and rising equity markets.

Revenue in the first half of 2013 was £8.7 million, down 5.4 per for the same period the previous year.

Unaudited profit before tax in the latest six-month period to 31 March was £1.5 million, compared with a loss of £2.7 million in the comparable period for 2012, including charges of £360,000 associated with the firm's share-based incentive scheme.

“With rising concerns about the pace of climate change, the quality of water and air, the reliability of harvests and the price of materials, investors are increasingly interested in exposure to companies active in resource efficiency and environmental markets. I am therefore pleased that Impax has delivered strong investment performance and secured significant inflows," said Ian Simm, chief executive of Impax.

The firm also announced that director Peter Gibbs was stepping down from the board. The role of senior non-executive director has been assumed by Mark White, and Vince O’Brien has become chairman of the remuneration committee.