It explains that some overseas markets require logs and lumber to be fumigated with methyl bromide gas before export, to ensure they are free of insect pests.

Fumigation is strictly regulated by the government in order to protect residents, passers-by, pets and plants from harm. However, methyl bromide damages the ozone layer which protects the planet from UV rays, so the government and forest industry are pulling out all stops to find alternatives.

Stakeholders in Methyl Bromide Reduction, the industry group that co-ordinates research into ways of reducing the use of methyl bromide, says forest owners and wood processors pride themselves on their environmental management, so are keen as everyone else to find ways to make the industry’s exports bug-free without harming the planet.

In the meantime, until alternative treatments are developed and approved by overseas authorities, it thanks the public for its patience. Although the industry is doing its best to find environmentally sustainable alternatives that are acceptable to overseas markets, this will be a gradual process.

Some people who live near ports are concerned that exposure to very low levels of the gas may cause nervous system illnesses like motor neurone disease (MND). This possibility was carefully investigated in a Nelson Marlborough District Health Board study in 2005. It found no evidence linking methyl bromide use at Port Nelson to cases of MND in the city. The recent ERMA reassessment of methyl bromide also found no link to MND.

“Like all chemicals, the toxicity of methyl bromide depends on how much a person is exposed to. At the levels used during fumigation – 10,000–30,000 parts per million (ppm) – it is highly toxic to humans, animals and insects. On the other hand, methyl bromide occurs naturally at trace levels in the atmosphere, and this poses no risk at all,” explains the brochure.

“In this respect, methyl bromide is similar to the carbon monoxide in car exhaust. Carbon monoxide is very dangerous when a car engine is run in a closed garage, but normally poses little risk in the open air.”

To download a web version of the brochure, click here.

For printed copies of the brochure (DLE format), please contact the Forest Owners Association, tel +64 4 473 4769, This email address is being protected from spambots. You need JavaScript enabled to view it.