If the government removed VAT from Bio-Pesticides then it would help to encourage farmers to use them, rather than the hazardous chemicals which are used most often. This would result in less dangerous chemicals being released into the atmosphere, and into our food chain. 

Pesticides are primarily used by farmers to protect their crops from creatures such as insects. They are supposedly used to help food production, however, there are still traces of these harmful chemicals on the foods we eat everyday, from supermarkets, market stalls and even school canteens. Research suggests that long term exposure to pesticides can lead to Parkinson's disease, depression, cancer and even death. They have also plays a huge part in the recent bee decline, and are a huge constantly affecting our environment.