Arch Chemicals said that second-quarter profit fell as lower volumes and unfavourable foreign exchange rates offset higher pricing and the favorable impact of the Advantis acquisition. Net earnings declined to $30.9 million, or $1.23 per share, from $33.2 million, or $1.33 per share, a year earlier, the Norwalk, Connecticut-based company said. Revenue fell to $414.2 million from $469.6 million.