The latest toxic waste emissions results have emerged in the US last week, against a backdrop of legal tussles.

The 2006 figures for the Environmental Protection Agency's Toxic Release Inventory (TRI) showed a two per cent reduction in toxic waste released into the environment by US facilities compared to 2005. The figure has fallen 24 per cent since 2001, says the data.

The TRI, which shows how toxic waste is managed in communities around the US, offers data on the entire range of chemical waste management methods, including source reduction, recycling, and treatment. The "disposal or other releases" category involves toxic chemicals that are disposed of untreated, on or off-site.

However, this year's report has been clouded by a twelve-state lawsuit issued in November, citing a change in the reporting rules passed by the EPA in December 2006. The lawsuit says that the new rules "unlawfully increase TRI reporting thresholds and as a result unlawfully weaken TRI data reporting requirements".

Under the rule change, reflected for the first time in the latest figures, six per cent more facilities were able to use a short-form reporting mechanism that did not require them to divulge information about the quantity of chemical handled.

The rule change allowed short form reporting for the management of persistent, bioaccumulative, and toxic (PBT) waste for the first time, for facilities managing up to 500lbs of that waste, as long as none of the PBTs are disposed of or otherwise released. It also increases the threshold for short-form reporting tenfold from 500lbs to 5,000lbs for non-PBT chemicals, as long as the amount released into the environment does not exceed 2,000lbs.

"The rule allows chemical plants to keep the public in the dark about persistent bioaccumulative toxins," said Greenpeace spokesperson Rick Hind, who has followed the TRI since its introduction in 1986. He suggested that the 2006 rule change would make many smaller facilities exempt from reporting quantities of chemicals.

According to the 2006 TRI figures, the 85 per cent of facilities reporting under 100,000lbs of toxic waste are increasing their toxic waste output. Facilities reporting more than that are reducing their amounts.

"The good thing is that before they can use the short form, they have already done something to reduce chemicals," responded EPA spokesperson Cathy Milbourne. "The changes really just streamline the reporting process. They still have to report."