Many common herbicides (weed killers) have been linked to a variety of human diseases, including breast cancer. It probably shouldnt surprise us that these compounds can be dangerous; they are designed to kill plants with which we share many common biological systems! Yes, humans and grass actually both depend on estrogen for proper regulation of cellular activity.
Several herbicides are known endocrine disruptors (they disrupt natural hormone-signaling pathways); endocrine disrupting chemicals have been implicated in increased risk for breast cancer, as well as other health problems. In addition to worrying about adult exposures to these chemicals, it is particularly important to not use toxic weed-killers on lawns where children play. Young children often spend much more time on the lawns, and tend to have direct exposure to the chemicals through walking barefoot and rolling in the grass. Because they are smaller, the exposure to chemicals actually leads to greater levels of the toxins in their bodies than for adults.
Whats this all got to do with breast cancer? We now know that exposures to toxic chemicals very early in life may predispose an individual to be more likely to be diagnosed with breast cancer, as well as many other disorders, many years or decades later.
Alternatives to use of herbicides include perhaps the most obvious, letting your lawn develop its natural combination of green (and other) plants. Frequent mowing leads to lawns that look grasslike in color, if not completely in content. Weeding by hand, of course, is great exercise. Use of ground cover, in place of grass, can provide an aesthetically pleasing look that is relatively weed-resistant and easier to care for than manicured grass coverage. And in limited spots, vinegar, salt, soapy water, and rubbing alcohol may help control weeds.
See 21 Organic Lawn Care Tips from a Real Expert.