COMBUSTION OF SOME PESTICIDES AND EVALUATION OF THE ENVIRONMENTAL-IMPACT

A method of combustion and sampling for small-scale laboratory experiments under defined conditions is described. The combustion products were analysed qualitatively and quantitatively, and their environmental impact and toxicology are reviewed. For sampling the organic combustion products, a three-step sampling system is necessary: a cold trap for cooling the combustion products, a filter to sample compounds which have condensed to particles, and an activated carbon tube to sample lower boiling compounds. The pesticides investigated in this study were 2-methyl-4-chlorophenoxyacetic acid, dimethoate and methyl parathion. During a real fire situation, the gaseous combustion products are the most dangerous to the fire-fighters and nearby residents. To protect the environment from disaster during a serious fire in a warehouse where pesticides are stored, the fire-fighters should perhaps not even try to extinguish the fire if it is widespread. Instead, they could protect the surroundings at the scene of the fire and could promote a fast hot fire to burn out all the organic material. This would raise the toxic gases higher into the atmosphere, where they would be diluted, thereby reducing the risk that residents living nearby would be exposed to very high, even lethal, concentrations of toxic gases. In this case, the environmental damage would also be minor, because the organic materials would not enter the soil and they would not be transported by fire-fighting water.