Ireland’s seasonally adjusted trade surplus fell by nearly €2 billion in September as imports rose, new figures from the Central Statistics Office show.

The trade surplus for September decreased by €1.984 billion, and is now at its lowest since April 2011. As a result, the seasonally adjusted trade balance narrowed to €2.9 billion in September, from August’s record monthly high of €4.9 billion.

Seasonally adjusted imports increased by €220 million (or 5 per cent) in the month, while exports decreased €1.7 billion (or 19 per cent) from the August high of €9 billion. The increase in imports was due mainly to imports of aircraft last month.

The EU remains the main source of imports accounting for 57 per cent of the value of imports in September 2012, with Great Britain accounting for 31 per cent.

On a seasonally adjusted basis, exports of €7.3 billion in September were 19 per cent lower than last month’s record level of exports and 7 per cent lower than the same month last year, mainly due to a decrease in the export of organic chemicals.

On an overall basis the EU accounted for 56 per cent of total exports in September 2012, while the US accounting for 21 per cent of total exports.

Exports of organic chemicals fell by €512 million in the month, while medical and pharmaceutical products declined by €261 million.

Declines in pharmaceutical sector output in September most likely herald a period of volatility in the Irish trade data with patents due to expire through 2012 and 2013, Davy Stockbrokers said in a note.

Exports of food and live animals increased (up €43 million) last month, as did exports for mineral fuels (up €48 million).