Distribution and outsource specialist Bunzl is on track this year so far despite a downturn at its UK and Irish operations."Despite a more difficult first quarter, overall trading is in line with full year expectations," Bunzl said.Revenues for the half year to June rose by 17%. Underlying revenue was marginally lower but consistent with recent levels allowing for exchange rate movements. "The more challenging economic environment has put some pressure on margins, with the UK & Ireland and the Rest of the World hit by lower revenue and the transactional effect of weaker sterling and the Australian dollar," Bunzl added.In North America, new business wins and additional business helped grow underlying revenue at a similar level to the previous year. Underlying revenue in the UK & Ireland is below last year, principally due to weaker performance of the less resilient market sectors. Continental Europe revenue is ahead of last year although underlying revenue softened due to the weaker economic environment throughout the region.