After 49 years of using atrazine at or above 80 million pounds per year, many target weed species have become atrazine-resistant [1, 2]. In fact, the number of documented atrazine-resistant “super” weeds number more than 80. No other herbicide has produced such dramatic effects on the evolution of weeds.
From the Atrazinelovers website, An explanation of what this chemical does: In addition to the ecological impacts on land, recently, the National Oceanic and Atmospheric Administration (NOAA), showed that atrazine negatively affects marine phytoplankton [3, 4].
These microscopic organisms serve as food for other organisms such as clams and oysters and the effect of atrazine is likely reflected throughout marine food webs: Phytoplankton serves as food for zooplankton which is in turn food for many larval and young fish and several species of whales. Thus, atrazine’s impact on this critical member of the marine foodweb will have dramatic and irreversible effects on marine life including damage to commercially important shellfish and finfish populations as well as sea mammals (whales) of which many are already threatened or endangered.
- Heap, I., The occurrence of herbicide-resistant weeds worldwide. Pestic. Sci, 1997. 51: p. 235-245.
- Gadamski, G., et al., Negative cross-resistance in triazine-resistant biotypes of Echinochloa crus-galli and Conyza canadensis. Weed Science, 2003. 48(2): p. 176-180.
- Rohr, J., et al., Multiple stressors and salamanders: Effects of an herbicide, food limitation, and hydroperiod. Ecological Applications, 2004. 14(4): p. 1028-1040.
- Rohr, J. and B. Palmer, Aquatic herbicide exposure increases salamander desiccation risk eight months later in a terrestrial environment. Environ. Toxicol. Chem., 2005. 24(5): p. 1253-1258.
- Fairchild, J., D. Ruessler, and A. Carlson, Comparative sensitivity of five species of macrophytes and six species of algae to atrazine, metribuzin, alachlor, and metolachlor. Environ. Toxicol. Chem., 1998. 17: p. 1830–1834.