Still not convinced herbicides can't and don't harm your health? If not, consider the many things glyphosate, the active ingredient of some of the most common herbicides used in farming. This piece from the Organic Consumers Association, citing the many ill health effects associated with glyphosate, alone should alarm you.
Just its pedigree alone -- it was first patented and sold by Monsanto under the trade name Roundup -- ought to send up red flags. Not to mention, exposure to glyphosate is the most common form of pesticide poisoning among landscapers in California.
However, those who support the use of glyphosate-based herbicides claim they're benign, environmentally friendly and, ultimately, breakdown in the environment very quickly. That may not explain why a factsheet developed by the EPA warns consumers about glyphosate in drinking water, or that as many as 20 million acres have been treated with more than 18 million pounds of that very same chemical in recent years.
Some herbicides using glyphosate, besides Roundup, and their manufacturers:
One of the best and easiest ways to avoid herbicides and pesticides altogether: Strive to eat organic foods as often as you possibly can.