The biggest problem our environment faces today in my opinion would be the genetic modification of food. With all of these food that have been genetically engineered, we are not in a position where we are putting foods into our bodies that are packed with toxins and diseases. These foods aren't natural and can have adverse effects, especially to wildlife.
Ultimately, these foods are not entirely environmentally friendly and have a much lower level of biodiversity. It's been proven by a number of scientists that these modified foods are not completely safe to consume - they can carry diseases and in more serious instances, cause death to both humans and animals.