Instruct: Classify a given review into positive or negative sentiment.
Query: A Landmark Work On A Very Important Subject!

According to the EPA, Dioxin is one of the most toxic poisons known to the human race. That's all the science I need to know. The author is a well known and respected environmentalist who writes passionately about the subject. It's a shame this issue has fallen off the radar screen. Chlorine is a menace to our health and the health of the planet. It's that plain and simple!