Press Release – Environmental Protection Authority Just over two months into its call for information on the herbicide glyphosate, the Environmental Protection Authority (EPA) has received over 80 responses. This weed killer has been used by home gardeners, farmers, and councils in New Zealand … Just over two months into its call for information on the herbicide glyphosate, the Environmental Protection Authority (EPA) has received over 80 responses. This weed killer has been used by home gardeners, farmers, and councils in New Zealand since the 1970s. Although it is commonly known as the active ingredient in Roundup, there are 89 mixtures containing glyphosate that are approved for use in this country.