Fluoride

Small quantities of particulate and gaseous fluoride emissions are mainly generated in aluminium smelters when converting alumina to aluminium.

Fluoride has been associated with impacts on human health. It can be taken up by plants and enter the food chain and can have an affect the strength of teeth and bones. However, we have controls in place to minimise any potential health and environmental impacts.

How we minimise the health risks

We identify and minimise all air pollutant emissions and their potential impacts by applying our Air Quality Control Standard.  We assess and prioritise them according to the significance of their impact, and then design and put in place the right emissions controls to ensure protection of ambient air quality.

Our results

• Our 2006 results show that reported fluoride emissions have increased by 10 per cent over 2005 levels.
• This net increase was primarily influenced by:

1. A gradual build-up of production at Rio Tinto Aluminium's new Yarwun facility.

2. An upgrade of the fluoride emissions measurement system at Rio Tinto Aluminium Bell Bay (resulting in higher reported figures).

3. Emissions control equipment at Boyne Smelters reaching the end of its lifecycle (due for replacement in early 2007).

4. Process and practice improvements at Anglesey Aluminium that resulted in a decrease in fluoride emissions, which partially offset the increases reported by other operations.