Admitting that its assessment based on computer models for destroying 250 animals, should be seen as “a first attempt at a difficult problem,” the DOH nevertheless warned that anyone less than two kilometres (1.25 miles) downwind of fires is likely to have dioxin intake above recommended safety levels. The model, which describes emissions for a “typical pyre”, also predicted that air concentrations of sulphur dioxide will exceed health limits up to 3.5 kilometres (2.2 miles) and have a “significant effect on asthma” at 1.5 kilometres (0.94 miles) from fires. Fine particulates will also exceed government standards at 3 kilometres (1.9 miles) from pyres.
The report criticism from environmentalists over the lack of use of the preferred options of disposal of carcasses outlined by the Environment Agency (EA) and concerns risks from the burning and burying of animals (see related story). The DOH, which said that the models are as realistic as possible, using two sets of meteorological conditions in the north-west for April and May, has warned that larger pyres will produce more pollutants. The benchmark measurement of two kilometres was chosen as, it said, the general public are unlikely to be exposed much closer than this to pyres.
The DOH also warned that “certain meteorological conditions” might occur, which would cause higher concentrations than those predicted in the model and produced health recommendations for pyres, including:
- keeping any pyre burning over 250 animals at least two kilometres from dwellings habitations and large pyres of more than 1,000 carcasses at least 3km away;
- choosing less-polluting materials for pyres, avoiding substantial amounts of PVC, tyres and wood treated with certain preservatives such as lindane;
- warning that asthma sufferers might experience a worsening of their condition and should have reliever medication available; and
- monitoring around pyres to improve understanding of emissions and deposition of pollutants.
Meanwhile, the EA issued its preferred hierarchy of disposal:
- rendering;
- incineration in authorised and regulated incinerators;
- use of appropriately engineered and authorised landfill sites;
- on-farm burning; and last
- on-farm burial.
However, the government has been criticised for relying too much on the least preferred options, but the Agency says it is “currently supporting a number of important initiatives” such as working with farmers to review possible on-farm burial sites and promoting the use of engineered landfill sites for disposal.