An environmentally friendly tropical crop could lead to hazardous increases in the levels of the air-pollutant ozone, according to new research.
The global production of palm oil now exceeds 35 million tonnes a year, with the average UK supermarket stocking hundreds of products containing it, from processed food such as margarine and cakes to cosmetics.
Palm oil is also used for biofuel as it is considered to be more environmentally friendly than fossil fuels.
However, an international team of scientists involved in a £2m joint UK-Malaysian research project, led by Lancaster University and funded by the Natural Environment Research Council (NERC), has discovered a downside to the increasing global demand for the crop.
A square kilometre of oil palm trees on a plantation emits five times as many volatile organic compounds (VOCs) – a major contributing factor to the ozone – as the same area of rainforest. Palm-oil plantations also emit more oxides of nitrogen than forests, from fertilised soil as well as from factories and vehicles on the plantations.
Project leader Prof Nick Hewitt, of the Lancaster Environment Centre at Lancaster University, said: ‘These compounds lead to the production of ground-level ozone, an air pollutant that damages human health, plants and materials, reduces crop productivity and has effects on the Earth’s climate. Although ozone levels are acceptable at the moment, they will increase if oxides of nitrogen are not controlled in the future.’
The study warns that large-scale palm production has the potential for very serious effects on air quality in Asia, as output rises with economic development, although, according to Hewitt, it is not too late to act.
‘The global demand for oil palm is shooting up and this is an early warning of an unfortunate and inadvertent consequence of producing this crop,’ he said. ‘The options are to manage the oxides of nitrogen emission by carefully controlling regional industrialisation and the use of fertiliser and fossil fuels in the plantations. The other option is to prevent oil palm trees producing VOCs through genetic modification.’
The study was conducted by the universities of Lancaster, Leeds, Leicester, East Anglia, Manchester, York, Cambridge and Edinburgh, l’Aquila University in Italy, the NERC’s Centre for Ecology & Hydrology and the National Centre for Atmospheric Sciences. It was funded by the NERC and was based in Danum Valley, one of the largest and most important protected areas of pristine lowland rainforests in Southeast Asia.
Danum Valley is home to the joint UK-Malaysia Sekhar Foundation & Royal Society’s South East Asian Rainforest Research Programme (SEARRP).