Oak processionary posed a health threat. In April 2018, an outbreak of the caterpillars was reported across Greater London and surrounding areas. The moth is now fairly common in Belgium, notably in the Campine but also elsewhere, with fluctuating population numbers from year to year. In 2007 infestations in the Belgian province of Limburg were so acute that soldiers were deployed to burn them. In the Netherlands, the caterpillars are dealt with by biological pest control. Local authorities use, like in Germany, fluids containing bacteria that are toxic only to the caterpillars. These fluids are sprayed onto the infected trees. Furthermore, an
Hazard substitution data, making alternatives assessments difficult. Another type of regrettable substitution involves shifting the burden of a hazard to another party. One example is that the potent neurotoxin acrylamide can be replaced with the safer "N"-vinyl formamide, but the synthesis of the latter requires use of the highly toxic hydrogen cyanide, increasing the hazards to workers in the manufacturing firm. In performing an alternatives assessment, including the effects over the entire product lifecycle as part of a life-cycle assessment can mitigate this. Hazard substitution Hazard substitution is a hazard control strategy in which a material or process is replaced with another